Take Blood Pressure in Both Arms, Study Says

By ANAHAD O'CONNOR

Doctors who make a habit of measuring blood pressure in only one arm may be doing their patients a disservice.
A new study shows that differences in blood pressure readings between a patient’s right and left arm could be a sign of vascular disease and a greater risk of dying from heart disease. The study, published in The Lancet, suggests doctors should always take blood pressure readings on both arms — an existing guideline that is widely ignored.
“Recommendations to measure both arms exist in both British and American blood pressure management guidelines,” said Dr. Christopher Clark, the lead author of the study and a clinical academic fellow at the Peninsula College of Medicine and Dentistry in England. “This is out there as guidance, but it’s guidance that isn’t regularly followed.”
In Britain, fewer than half of all doctors say they make a habit of measuring blood pressure in both arms, Dr. Clark said, a statistic that is likely to be similar in the United States.
The consequences could be significant. In their study, Dr. Clark and his colleagues pooled data from their own research and from about two dozen other studies looking at differences in systolic blood pressure readings between the two arms in patients. Systolic pressure, the top number in a reading, reflects the amount of pressure that blood exerts on vessels while the heart is contracting.
Although seemingly minor, a difference of 15 millimeters of mercury or more between systolic readings in the two arms meant the risk of peripheral vascular disease was two and a half times greater and the risk of cerebrovascular disease was 1.6 times higher. It was also associated with a 70 percent greater risk of dying from heart disease. The precise number of the higher or lower systolic reading was less important than the extent of the difference between them. A difference of even 10 millimeters was enough to raise the risk of peripheral vascular disease.
The authors hypothesized that different blood pressure readings in the two arms were a sign of the narrowing or hardening of a person’s arteries, particularly on one side of the body.
Dr. Clark said the need for measuring blood pressure in both arms was clear.
“If we don’t know to measure both arms, we’re not going to make the right diagnosis and the right treatment choices for our patients,” he said. “If you measure an arm where the blood pressure is lower than the other arm, you may be falsely reassured that the blood pressure is normal or is being adequately treated, when in fact the blood pressure is still high.” 

Physician Says Proposed FDA Regulations On Supplement Industry Not Enough.

FDA The Los Angeles Times  (1/27, Healy) "Booster Shots" blog reports, "A new proposal to toughen the Food and Drug Administration's power to regulate dietary supplements has the makers of vitamins, minerals and botanical extracts up in arms." However, "an editorial in the New England Journal of Medicine [NEJM] says the drug-safety agency's proposed new powers do not go nearly far enough." The Times notes that the dietary supplements industry, which "produced and marketed 4,000 distinct products in 1994, when the regulatory framework for dietary supplements was written into law, now markets about 55,000 products to Americans who believe them to be safe to take."

        MedPage Today  (1/27, Walker) reports, "More than 100 million Americans spend more than $28 billion on vitamins, minerals, herbal ingredients, amino acids and other natural products in the form of dietary supplements each year, 'assuming they are both safe and effective,' wrote Pieter A. Cohen, MD, of Harvard Medical School and the Cambridge Health Alliance" in the NEJM. However, "they have no assurance that the products are safe because FDA regulation of supplements is too weak, Cohen wrote." The agency's "'guidance provides a thoughtful framework for evaluating the safety of new ingredients and if implemented it would lead to substantial improvement in safety,' Cohen wrote, but he said he didn't think the FDA goes far enough."

Federal Court Decision Allows Watson To Market Generic Lovenox.

Dow Jones Newswires  (1/27, FitzGerald, Subscription Publication) reports that the US Court of Appeals for the Federal Circuit has stayed a decision that blocked Watson Pharmaceuticals Inc. from selling its generic blood thinner. The court's decision postponed an injunction issued in October that had prevented Watson and partner Amphastar Pharmaceuticals Inc. from selling their version of Lovenox [enoxaparin], a blood thinner from Sanofi. Amphastar's abbreviated drug application for enoxaparin sodium was approved by the Food and Drug Administration.

Study finds 7% of Americans have oral HPV infections.

USA Today (1/27, Szabo) reports, "Oral infections with HPV, a family of cancer-causing viruses, are more common than doctors expected, according to the first national study of its kind." What's more, "while the viruses can be found in saliva, HPV appears to be mostly spread through sex, rather than more casual contact such as kissing," according to a study published Jan. 26 in the Journal of the American Medical Association. "HPV, the human papillomavirus, is best known for causing cervical cancer and genital warts, but it also causes cancers at the back of the throat, tonsils and base of the tongue, says study author Maura Gillison, a professor at the Ohio State University Comprehensive Cancer Center."

        "HPV is best known as the cause of cervical cancer, which kills 4,220 women in the US each year, according to the National Cancer Institute.," the Los Angeles Times (1/27, Roan) adds. According to a US Centers for Disease Control and Prevention survey "released last year," it "found that about 90% of adults have had oral sex, along with 27% of 15-year-old boys and 23% of 15-year-old girls." In "a study published in October in the Journal of Clinical Oncology" it "traced more than 70% of new cases of oral cancers to HPV infection, putting it ahead of tobacco use as the leading cause of such cancers."

        The New York Times (1/27, O'Connor) "Well" blog explains, "The research is the first major study to document the nationwide prevalence of oral human papillomavirus, or HPV, a disease that has drawn growing attention from public health experts because it has fueled a rise in oropharyngeal cancers affecting the back of the tongue and the throat." The article points out that "while the overall prevalence of HPV was about 7 percent, only 1 percent, or roughly two million people, were infected with HPV 16, the strain linked to throat cancers and many cases of cervical cancer."

        The AP (1/27, Tanner) reports, "Overall, 7 percent of Americans aged 14 to 69 are infected, the study found." However, "the results are not cause for alarm. While mouth cancers are on the rise -- probably from oral sex -- most people with oral HPV will never develop cancer." But "experts say the study provides important information for future research that could increase knowledge about who is most at risk for oral cancer and ways to prevent the disease."

        ABC News (1/27, Gann) reports in its "Medical Unit" blog that "men were at three times greater risk than women for infection with the virus, particularly from age 30 to 34 and 60 to 64." The piece adds, "More oral sex with less protection may be one reason why the risk of oral HPV was so heavy for men, though the study didn't provide any official reason for the gender difference in infection." The researchers "speculated that the virus may have an easier time transmitting orally in men than in women, or that other factors like smoking that are more common among men could facilitate transmission."

        "There are two peaks in the age people are infected -- 30 to 34 and 60 to 64, according to the study published today in the Journal of the American Medical Association," Bloomberg News (1/27, Lopatto) reports. "Besides sex, other demographics associated with oral HPV infection include age, lifetime number of sex partners, and the number of cigarettes smoked each day." According to the study, "among the 2,483 men who participated in the study conducted in 2009 and 2010, 264 had an oral HPV infection," and "of the 2,385 women, 88 had an oral infection."

        The Washington Times (1/27, Wetzstein) reports, "The study...has broad implications for head and neck cancers, which already strike 50,000 people a year and are increasingly being caused by human papillomavirus (HPV)." Dr. Maura L. Gillison and her colleagues said, "The new study finds that the 'most prevalent' HPV strain found in people's mouths is HPV-16, a type that is particularly likely to cause cancers." The study used "data...from oral-fluid samples collected from some 5,000 people ages 14 to 69 as part of the National Health and Nutrition Examination Survey." Also covering the story are BBC News (1/27), MedPage Today (1/27, Bankhead), and HealthDay (1/27, Mozes).

FDA declines expanded approval for cholesterol drugs.

Bloomberg News (1/26, Edney) reports, "Merck & Co., the second-biggest US drugmaker, said cholesterol treatments Vytorin [ezetimibe/simvastatin] and Zetia [ezetimibe] failed to win" Food and Drug Administration "approval to prevent heart attacks and strokes in patients with chronic kidney disease." The agency "will allow the company to add study data to Vytorin's label showing the treatment effectively lowers bad cholesterol in those patients," the company said in a statement. Merck said, "The agency rejected the expanded use because a study of the drugs didn't examine the independent contributions of each medicine." Also covering the story is Reuters (1/26, Yukhananov).

        FDA approves new label for ezetimibe-simvastatin. MedPage Today (1/26, Kaiser) reports, "The FDA has approved new labeling for the single-tablet combination of ezetimibe-simvastatin (Vytorin), a cholesterol-lowering drug, for use in patients with moderate to severe chronic kidney disease (CKD)." The agency "however, only updated the label and did not approve a new indication for the drug because the SHARP study examining its efficacy was not designed to assess the independent contributions of ezetimibe (Zetia) and simvastatin (Zocor) to the observed effect," Merck said in a statement. "The FDA's Endocrinologic and Metabolic Drugs Advisory Committee also voted 10-6 against recommending approval for use of the drug in end-stage renal disease (ESRD) patients on dialysis." Also covering the story is Reuters (1/26).

USDA issues new school nutrition guidelines.

ABC World News (1/25, story 9, 0:25, Muir) reported, "First Lady Michelle Obama teamed up with Rachael Ray to unveil the biggest overhaul on school meals in more than 15 years. There will be more whole grains, less salt and a wider selection of fruits and vegetables and all milk must now be low fat. But the new rules do not go as far as the Administration had hoped."

        NBC Nightly News (1/25, story 8, 1:00, Williams) reported that "based on the new government regulations, schools will begin to cut back on sodium, sugar, saturated fats and transfats and instead add more fresh fruits, vegetables and whole grains," Education Correspondent Rehema Ellis said. "Next fall you start to see something like this. Whole wheat spaghetti, more fresh fruits and vegetables and green vegetables, as well as 1% milk."

        "The quality of school meals has been hotly debated for years because one-third of children in the USA are overweight or obese," USA Today (1/26, Hellmich) points out. "The rules released today apply to school meals; regulations for other foods such those served in à la carte lines, vending machines and stores will come later." The new plans "are designed to improve the health of nearly 32 million children who eat lunch at school every day and almost 11 million who eat breakfast."

        The Washington Post (1/26, Elboghdady) reports, "The meals will continue to include pizza and french fries because Congress, after heavy lobbying from the food industry, derailed the Obama administration's original plan to limit tomato paste and starchy vegetables such as potatoes." However, "as the Agriculture Department was crafting the final guidelines, opponents raised concerns about the program's estimated $6.8 billion price tag over the next five years and the financial burdens it would place on school districts." As a result, "the administration slashed the cost to $3.2 billion."

        "The updated school lunch standards are expected to spell the end of mystery meat and of ketchup as a vegetable, ushering in offerings such as whole wheat pasta, fresh cantaloupe, grilled chicken and chef salads," the Los Angeles Times (1/26, Healy) "Booster Shots" blog adds. "Schools are expected to phase in changes to their menus over the next three years, starting with the 2012-2013 school year," Agriculture Secretary Tom Vilsack said. "Some of the new guidelines do not break new ground -- no more than 10% of school lunch calories should come from saturated fat, for instance."

        The Washington Post (1/26, Huget) "The Checkup" blog reports the new "guidelines...place new restrictions on the number of calories (according to age group), milligrams of sodium and percentages of calories from saturated fat children's meals may contain." What's more, "they require half (and eventually all) of the grains served to be whole-grain-rich."

        The Wall Street Journal (1/26, Tomson, Subscription Publication) quotes first lady Michelle Obama, who said, "When we send our kids to school, we have a right to expect that they won't be eating the kind of fatty, salty, sugary foods that we're trying to keep from them when they're at home." The Centers for Disease Control and Prevention estimates that 17% of kids between two and 19 years of age are obese.

        Reuters (1/26, Simpson) reports schools will also receive an additional 6 cents per meal under the new plan and the USDA will also inspect school menus more frequently. In a statement, the USDA said, "Food and beverages sold in vending machines and other school sites 'will also contribute to a healthy diet.'"

        "The new standards include offering fruits and vegetables every day, increasing whole grain-rich foods, serving only fat-free or low-fat milk, limiting calories based on children's ages, and reducing the amounts of saturated fat, trans fats and sodium, according to a news release from the US Department of Agriculture," HealthDay (1/26, Reinberg) adds. Also covering the story are MedPage Today (1/26, Fiore), the AP (1/26, Jalonick), Bloomberg News (1/26, Armour), the UK's Daily Mail (1/26), and Bloomberg News (1/26, Armour).

Protein-free diet before surgery may prevent reperfusion injury.

The Washington Post (1/26, Brown) reports a rat study in Science Translational Medicine showing that certain dietary restrictions before surgery may be beneficial. The study showed that "removing protein from [the rats'] diet for about a week dramatically protected rats from damage to kidneys and livers when blood flow was temporarily cut off from those organs," which is similar "to what...can happen to organs during long and complicated operations." The Post explains that the protein-free "diet appears to protect against 'reperfusion­injury.'" In addition, giving rats halo­fuginone, which "mimics deprivation of proline, an amino acid essential during times of illness or stress" also protected rats from organ damage. Researchers "are now making plans for a study in which some patients would have a three-day 'juice-only fast' before surgery."

Risk of Cardiac Death Pretty Much Set by 55

By Crystal Phend, Senior Staff Writer, MedPage TodayPublished: January 25, 2012
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

4 comment(s)

Action Points

• Two or more major risk factors for cardiovascular disease such as hypertension, elevated cholesterol, diabetes, and smoking at age 55 predicted 29.6% chance of death from cardiovascular disease by age 80 for men and 20.5% for women.
• For 55-year-olds without cardiovascular risk factors, lifetime risk was only 4.7% for men and 6.4% for women.

Even a couple of traditional cardiovascular risk factors in middle age spell high lifetime risk for the heart, researchers affirmed.
Two or more major risk factors at age 55 predicted a 29.6% chance of death from cardiovascular disease by age 80 for men and 20.5% for women, Donald M. Lloyd-Jones, MD, of Northwestern University in Chicago, and colleagues found.
But for 55-year-olds with a clean bill of cardiovascular health, lifetime risk was only 4.7% for men and 6.4% for women in the analysis of patient-level data from more than 250,000 individuals across 18 longitudinal studies.
The effect was similar for heart attacks and strokes and regardless of race or era in which one was born, the group reported in the Jan. 26 issue of the New England Journal of Medicine.
Risk assessment typically considers only short-term risk, such as 10-year risk with the Framingham prediction tool, the group noted.
"However, the majority of adults in the U.S. who are considered to be at low risk for cardiovascular disease in the short term are actually at high risk across their remaining lifespan," Lloyd-Jones and colleagues wrote.
Telling individuals they are safe until short-term risk becomes high may not be the best strategy, they suggested.
Instead, "efforts to lower the burden of cardiovascular disease will require prevention of the development of risk factors (primordial prevention) rather than the sole reliance on the treatment of existing risk factors (primary prevention)," the group concluded.
Their Cardiovascular Lifetime Risk Pooling Project pulled together cohort studies done over the past 50 years in order to dig deeper into risk factors than possible with any single data set.
Altogether, only 5% of the 257,384 studies' participants had an optimal cardiovascular risk factor profile, with total cholesterol under 180 mg/dL, blood pressure under 120/80 mm Hg, and no smoking or diabetes.
Having one major traditional risk factor -- smoking, diabetes, treated high cholesterol or an untreated level of at least 240 mg/dL, treated hypertension or untreated 160 mm Hg systolic or 100 mm Hg diastolic or higher -- was most common, accounting for about 40% of individuals across middle and older age ranges and gender groups.
Roughly another quarter had two or more major risk factors from that list.
Lifetime cardiovascular risks were "very low" with no risk factors in middle age but rose dramatically with even one or two risk factors.
Two or more major risk factors at 55 predicted drastically higher lifetime risk of fatal coronary heart disease or nonfatal myocardial infarction (MI) compared with having an optimal risk-factor profile (37.5% versus 3.6% among men and 18.3% versus less than 1% among women).
Likewise, fatal or nonfatal stroke risk was lower with no versus two or more major risk factors (2.3% versus 8.3% among men and 5.3% versus 10.7% among women).
For the overall risk of death from cardiovascular causes and for nonfatal MI, men carried about twice the lifetime risk of women. Stroke risk didn't differ much by gender.
For the same gender and level of risk factors, black individuals weren't more likely to die from cardiovascular causes than were white individuals, although the burden of risk factors was higher among blacks.
At the same age, individuals born more recently had fewer risk factors but roughly the same risk when risk factors were present.
"The presence or absence of traditional risk factors appears to represent a much more consistent determinant of the long-term risk of cardiovascular disease than race or birth cohort," the researchers concluded.
They cautioned that including treated patients in the analysis may have underestimated future risk, although such patients represented just a small proportion of the overall cohort.
Another limitation was that lifetime risk couldn't be estimated for individuals assessed in the most recent decade due to the short follow-up.
But because of the consistency of the results across the various birth cohorts included in the analysis, the findings likely generalize to people today, Lloyd-Jones' group noted.

The study was supported by grants from the National Heart, Lung, and Blood Institute, by funding from the Dedman Family Scholar in Clinical Care endowment at UT Southwestern Medical Center, and by an American Heart Association grant.
Lloyd-Jones reported funds paid to his institution from the NHLBI and AHA without any conflicts of interest to disclose. Several co-authors' institutions also received funds from NIH/NHLBI and AHA. Berry reported receiving funds from Merck. Tracy reported receiving funds from Merck, Tibotec-Johnson & Johnson, Abbott, and from two law firms for consulting, and is the owner of Haematologic Technologies.

From the American Heart Association:

• Cardiovascular Risk in Asymptomatic Adults

Primary source: New England Journal of Medicine
Source reference:
Berry JD, et al "Lifetime risks of cardiovascular disease" N Engl J Med 2012; 366: 321-329.

Amputations Due To Diabetes Fell More Than Half Since Mid 1900s.

The AP  (1/25) reports, "Foot and leg amputations were once a fairly common fate for diabetics, but new government research" found that "the rate has fallen by more than half since the mid-1990s," decreasing "from more than 11 to about 4 per 1,000 people, the Centers for Disease Control and Prevention reported Tuesday." In the study, investigators "checked national hospital discharge records for 1988 through 2008, looking for patients aged 40 and older who had lost a toe, foot or leg to diabetes." The AP adds, "While diabetes has been growing more common in the United States - driven by obesity-related Type 2 - researchers have noted recent declines in some of the other most dreaded complications, including blindness and kidney failure." The study  was published in Diabetes Care.

        CQ  (1/25, Adams, Subscription Publication) reports, "The study authors - five officials affiliated with the CDC's Division of Diabetes Translation - could not clearly identify why the rate of amputations declined among diabetics. But because the number of amputations decreased among diabetics but not non-diabetics, the officials theorized that the decline may be partly attributable to better diabetes care management or the reduction of risks that could lead to amputation." Despite the decline, however, "the rates of diabetes-related amputations remained higher among patients who are 75 years old or older, African-Americans and men."

        MedPage Today  (1/25, Fiore) adds, "Among diabetes patients ages 40 and up, hospital discharge rates for nontraumatic lower-extremity amputation fell an average of 8.6% per year between 1996 and 2008 (P<0.01)." MedPage also reports that the researchers "assessed data from the 1988-2008 National Hospital Discharge Survey and the National Health Interview Survey." HealthDay  (1/25, Preidt) also reports the study.

Tumor Necrosis Factors Predict Kidney Disease in Diabetes

By Kurt Ullman, Contributing Writer, MedPage Today  MedPage Direct Link
Published: January 24, 2012
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

Action Points

• These studies found that levels of circulating tumor necrosis factor receptor 1 and 2 (TNFR1 and TNFR2) predict kidney disease in both type 1 and type 2 diabetes.
• Among those with type 1 diabetes, patients with the highest quartile of TNFR2 values were three times more likely to have renal decline than those in the other quartiles, and the risk associated with high TNFR1 values was slightly less than that seen in those with elevated TNFR2.

Levels of circulating tumor necrosis factor receptor 1 and 2 (TNFR1 and TNFR2) predict kidney disease in both type 1 and type 2 diabetes, according to the results of two 12-year studies.

The cumulative incidence of end-stage renal disease (ESRD) among those with type 2 diabetes who had the highest quartile of TNFR1 at baseline was 54% at 12 years, compared with only 3% for the other quartiles (P< 0.001), reported Andrzej S. Krolewski, MD, PhD, from the Joslin Diabetes Center in Boston, and colleagues.

Among those with type 1 diabetes, the cumulative incidence of estimated glomerular filtration rate less than 60 mL/min per 1.73 m² for those in the highest quartile of TNFR2 was 60% after 12 years, compared with 5% to 19% in the other quartiles. Both studies were published online ahead of print in the Journal of the American Society of Nephrology.
The Joslin Study of the Genetics of Type 2 Diabetes and Kidney Complications enrolled 410 people between 1991 and 1995. At the end of 2004, 267 (65.1%) were still alive. ESRD had developed in 59 patients, of whom 51 had died.
The patients in the type 1 diabetes study were draawn from from two different Joslin studies with a total enrollment of 628. All had high normal GFR at baseline. The researchers used progression to chronic kidney disease stage 3 or above (CKD³) over the 12-year observation period as the primary outcome.
In both instances, several dozen possible markers for inflammation in blood and urine were obtained at baseline. The subjects' kidney function and status were then followed during the course of 12 years.
The impact on kidney function in those with both types of diabetes is well-known, and the researchers wanted to examine the TNF pathway as a possible predictive marker for renal disease.
In the type 2 diabetes study, concentrations of markers for endothelial dysfunction and systemic inflammation were similar in all three groups. Concentration of markers for the TNF pathway (free TNF alpha, total TNF alpha, TNFR1 and TNFR2) were highest among those developing end-stage renal disease, and intermediate for those who died from non-kidney-related causes.
There also was a high intercorrelation among the pathway markers, particularly TNFR1 with TNFR2 (Spearman correlation r=0.90, P<0.001). This was not related to cross-reactivity between the antibodies used for the assay, according to the researchers.
When they looked at those patients with proteinuria at baseline, the cumulative risk of renal disease in the highest quartile of TNFR1 rose steeply and at a constant rate throughout the study. Among those without proteinuria, the first cases of ESRD did not begin to show up for six years.
A Cox proportional hazard analysis controlling for influential clinical characteristics found that each of the TNF pathway markers remained significant. The effects of both TNF receptor markers were similar to that of total TNF alpha, but were much stronger. When both TNFR1 and TNFR2 were entered into the model, the effect of TNFR1 remained significant but TNFR2 did not.
Among those with type 1 diabetes, patients with the highest quartile of TNFR2 values were three times more likely to have renal decline than those in the other quartiles (HR 3.0, 95% CI 1.7 to 5.5). The risk associated with high TNFR1 values was slightly less than that seen in those with elevated TNFR2.
As with type 2 diabetes, the risk was higher over time among those with higher TNF markers. For patients in the highest quartile of TNFR2, the cumulative risk of being in CKD class 3 or better increased steeply at a constant rate from the beginning. Among those in the lower quartiles, cases were fewer and occurred later.
When entered into the Cox models with the influential characteristics, the effect of TNFR2 was strongest with TNFR1 close behind, while total and free TNF alpha no longer was significant. In pairwise comparisons across the TNF pathway makers, TNFR2 was dominant.
One of the limitations was the use of less-than-certain documentation among the 19 patients who had indications of kidney-related death on death certificates but were not registered. There also was some concern with miscalculation of patients due to biologic variation in the assessment of baseline characteristics. There was also a high concentration of Caucasians among the participants that might limit its usefulness among other racial/ethnic groups.
Despite the limitations, "(our) findings in type 1 and type 2 diabetes point to the specific involvement of TNFR-mediated pathway rather a general inflammation in the development of renal function decline and progression to ESRD," the authors concluded.
Results from the two studies may help speed the search for new therapeutic agents to prevent or slow the kidney decline seen in diabetes, they wrote.

The studies were funded by grants from the Juvenile Diabetes Research Foundation, the National Institutes of Health, the American Diabetes Association, the Uehara Memorial Foundation, the CONACYT Fundacion Mexico en Harvard, and a grant from Yasuhiko Tomino of Juntendo University in Tokyo to one of the investigators.
The authors reported no disclosures for either study.

Primary source: Journal of American Society of Nephrology
Source reference:
Godha T, et al "Circulating TNF receptors 1 and 2 predict stage 3 CKD in type 1 diabetes" J Am Soc Nephrol 2012; 23: DOI: 10.1681/ASN.2011060628
Additional source: Journal of the American Society of Nephrology
Source reference:
Niewczas MA, et al "Circulating TNF receptors 1 and 2 predict ESRD in type 2 diabetes" J Am Soc Nephrol 2012; 23: DOI:10.1681/ASN.20111060627

Optimal potassium level after MI differs from guidelines, study finds

Post-myocardial infarction inpatients with blood potassium levels between 3.5 and 4.5 mEq/L had a lower mortality risk than those with levels higher or lower than this range, a new study found.
Current guidelines recommend maintaining serum potassium levels between 4.0 and 5.0 mEq/L in acute myocardial infarction (AMI) patients, but most studies on which the guidelines are based occurred before the routine use of beta-blockers, reperfusion therapy and early invasive management for eligible patients, the study authors noted. Those previous studies also focused on ventricular arrhythmias, not mortality, they said.
For their retrospective cohort study, the researchers examined data from 38,689 patients with AMI confirmed by biomarkers, who were admitted to 67 U.S. hospitals from 2000 through 2008. All patients had serum potassium measured in the hospital and were categorized by mean level after admission as <3.0, 3.0 to <3.5, 3.5 to <4.0, 4.0 to <4.5, 4.5 to <5.0, 5.0 to <5.5 or ≥5.5 mEq/L.
Researchers found a U-shaped relationship between mean post-admission potassium level and in-hospital mortality. Nearly 7% of study patients (n=2,679, or 6.9%) died during hospitalization. Compared with the reference group (3.5 to <4.0 mEq/L; mortality rate, 4.8%), the group with levels of 4.0 to <4.5 mEq/L had similar mortality (5.0%). Patients with levels of 4.5 to <5.0 mEq/L had double the mortality rate (10%), and mortality was even higher for those at 5.0 mEq/L or higher.
Mortality rates were also higher for patients with potassium levels <3.5 mEq/L. However, rates of ventricular arrhythmias or cardiac arrest were higher (compared to the reference group) only for those with the lowest and highest average potassium levels (i.e, <3.0 mEq/L and ≥5.0 mEq/L). The study was published in the Jan. 11 Journal of the American Medical Association.
The findings "challenge current clinical practice guidelines" and suggest the optimal range of potassium levels in AMI patients is between 3.5 and 4.5 mEq/L, while levels greater than 4.5 mEq/L "should probably be avoided," the authors wrote. Editorialists largely agreed, saying potassium repletion for levels lower than 3.5 mEq/L "remains reasonable," while repletion for levels between 3.5 mEq/L and 4.0 mEq/L doesn't seem justified—and neither does targeting levels above 4.5 mEq/L.

Study: Research Limited On Costs, Inefficiencies Linked To Healthcare Overuse.

Modern Healthcare  (1/24, McKinney, Subscription Publication) reports on an Archives of Internal Medicine article  , which said that "despite concerns about the high cost and inefficiency associated with the overuse of healthcare, research is limited and often addresses only a few medical interventions." The authors explained that "most studies measure overuse of antibiotics for upper respiratory infections, coronary artery bypass grafting, coronary angiography and carotid endarterectomy," and "emphasized the need for better guidelines on a wider range of healthcare interventions as a way to boost research on overuse, particularly in areas such as preventive diagnostic services."

Injection with iodine contrast may raise risk of thyroid disorders.

Bloomberg News (1/24, Ostrow) reports, "Chemicals used to enhance pictures obtained from medical imaging tests may lead to overactive or underactive thyroid glands, a study showed. Patients injected with contrast material were about twice as likely as those who didn't get the chemical to develop hyperthyroidism, when the gland produces too much thyroid hormone and can cause rapid or irregular heart rates, according to a study today in the Archives of Internal Medicine. Results also showed an increased risk for hypothyroidism."

        The New York Times (1/24, O'Connor) "Well" blog notes, "Iodide, a form of the chemical element iodine, is widely used as a radiocontrast agent to allow doctors to see blood vessels and tissues in medical imaging tests. In a typical year, about 80 million doses of iodinated contrast agents are administered worldwide, largely for CT scans, cardiac catheterizations and other angiograms." The blog also notes that this study "examined data on" about 2,000 patients "who were treated at Boston-area hospitals for various conditions and followed over a 20-year period."

        Medscape (1/24, Keller) details, "Researchers found a statistically significant association between ICM exposure and incident hyperthyroidism (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.08 - 3.60; P = .03), but not incident hypothyroidism (OR, 1.58; 95% CI, 0.95 - 2.62; P = .08)." A commentary noted "that the study was conducted in the Boston area, which has sufficient dietary iodine intake, so the results may not be generalizable to parts of the world with insufficient intake."

Women report feeling more pain than men.

NBC Nightly News (1/23, story 8, 0:30, Guthrie) reported, "A Stanford Medical Center study found women report feeling more pain than men do on a variety of common ailments including back and neck injuries, digestive problems and sinus infections. The author said part of the reason women reported much higher levels of pain could be because men simply don't want to admit how much pain they experience."

        "New research from Stanford University suggests that even when men and women have the same condition -- whether it's a back problem, arthritis or a sinus infection -- women appear to suffer more from the pain," the New York Times (1/24, Parker-Pope) "Well" blog adds. "The study, published Monday in The Journal of Pain, analyzes data from the electronic medical records of 11,000 patients whose pain scores were recorded as a routine part of their care." According to the study, "for 21 of 22 ailments with sample sizes large enough to make a meaningful comparison, the researchers found that women reported higher levels of pain than men."

        On its front page, the San Francisco Chronicle (1/24, A1, Allday) reports, "The study being released today found that when asked to rate their pain on a scale of 0 to 10 -- with 0 being no pain at all, and 10 being the worst pain imaginable -- women on average scored their pain 20 percent more intense than men." What more, "the results held up across a wide variety of diseases and injuries, including back and neck pain, digestive disorders, sinus infections, and even ankle strains and sprains." But "the fact that women report more pain overall doesn't necessarily mean they have more or less tolerance to pain than men," study lead author Dr. Atul Butte said.

        "Authors cautioned that this study cannot determine whether pain is actually experienced more intensely by women or whether women simply communicate better with their health care providers about pain," ABC News (1/24, James, Chuang) points out. "But many other medical experts are skeptical about the Stanford study" since "the authors didn't account for the possibility that if many women had additional diseases that caused pain, it could actually be the other diseases, and not their gender, which is responsible for the women having more pain than men." Dr. Lloyd Saberski, medical director of the Advanced Diagnostic Pain Treatment Centers at Yale University, said, "It's a flawed study."

        CBS News (1/24, DyBuncio) reports that "since the data were self-reported, the explanation may be that women more readily report pain than men do." Another explanation for the difference may be that "since nurses often take these records, men may have been more reluctant to admit their pain to female nurses. Or the difference may be hormonal." Also covering the story are the Wall Street Journal (1/24, Shea) "Ideas Market" blog, San Jose Mercury News (1/24, Shen), and the New York Daily News (1/24, Murray).

Stem cell treatment may help patients with macular degeneration.

The CBS Evening News (1/23, story 6, 3:00, Pelley) reported, "There is a new treatment for the leading cause of blindness in older people. The treatment uses embryonic stem cells and a study says that it shows promising results."

        The Washington Post (1/24, Stein, Brown) reports that the treatment has "apparently" restored "some vision for at least one and possibly two women losing their sight to incurable forms of progressive blindness." Being that "the women were the first to volunteer for an experiment designed primarily to test the safety of injecting an embryonic stem cell therapy into people, scientists are being cautious."

        The Los Angeles Times (1/24, Kaplan) "Booster Shots" blog reports that "the patients -- one with dry age-related macular degeneration and the other with a pediatric version of the disease called Stargardt's macular dystrophy -- were treated at UCLA over the summer. The therapy was developed by Advanced Cell Technology Inc., and the company funded the study."

        USA Today (1/24, Vergano) reports that "surgeons...injected 50,000 cells each into one eye of" the "two women." The researchers found that, "four months after the injections, neither study patient had lost vision, as usually happens in progressive blindness, or showed signs of abnormal growth in their eyes, quelling fears associated with the cells that they could give rise to tumors." The "patient with Stargardt's macular dystrophy...saw demonstrably improved vision, while the other patient's improvement looked more ambiguous."

        However, the Time (1/24, Szalavitz) "Heathland" blog reports that "experts said the improvement of the macular degeneration patient might be mostly psychological, because the vision in her untreated eye appeared to get better too."

        The New York Times (1/24, B7, Pollack, Subscription Publication) reports, "The paper," published in the Lancet, "comes two months after the Geron Corporation cast a pall over the field by abruptly halting the world's first clinical trial based on embryonic stem cells - one aimed at treating spinal cord injury. Geron, which has not published results from the aborted trial, also said it would abandon the entire stem cell field." However, "the results reported Monday could help lift some of that pall."

        CNN (1/24, Cohen) notes that the patients "had to take anti-rejection drugs for a short period so their eyes wouldn't reject the foreign tissue."

        The Boston Globe (1/24, Conaboy) reports, "The patients were the first in trials that will study the use of the cells in 24 people. The researchers injected the first patient in a separate trial in Europe on Friday."

        Bloomberg News (1/24, Frier) reports that "both patients have requested treatment in their other eye," according to Advanced Cell Chief Scientific Officer Robert Lanza.

        According to MedPage Today (1/24, Smith), the researchers "reported that controlled differentiation of the cells resulted in a culture of retinal pigment epithelium cells that was 99% pure and, in animals, injection of the retinal cells was not associated with tumor formation or with any other safety issues." Also covering the story are the Wall Street Journal (1/24, Hobson) "Health Blog," the National Journal (1/24, Fox, Subscription Publication), Reuters (1/24, Begley), WebMD (1/24, DeNoon), and HealthDay (1/24, Preidt).

High-Fiber Diet No Help for Diverticulosis

By Charles Bankhead, Staff Writer, MedPage Today MedPage Direct Link
Published: January 23, 2012
Reviewed by Zalman S. Agus, MD; Emeritus Professor
University of Pennsylvania School of Medicine and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

3 comment(s)

Action Points

• Risk factors for diverticulosis are typically thought to include a low fiber diet, a high intake of red meat and fat.
• In this study, though, a high-fiber diet did not protect against asymptomatic diverticulosis, and, in fact, was associated with a greater prevalence of the condition.

A high-fiber diet afforded no protection against asymptomatic diverticulosis, findings from more than 2,000 colonoscopy exams showed.
In fact, patients who ate the most fiber had the highest prevalence of diverticulosis, about 30% higher than people who consumed the least dietary fiber.
Moreover, constipation did not increase the risk of diverticulosis -- just the opposite. People who had fewer than seven bowel movements a week had a lower prevalence than those with more frequent BMs.
The findings, reported online in Gastroenterology, confound conventional wisdom about colon health.
"Our data demonstrated no association between fat, red meat, physical activity, and diverticulosis," Robert S. Sandler, MD, of the University of North Carolina in Chapel Hill, and co-authors wrote in conclusion.
"Based on our results, previous hypotheses regarding diverticulosis risk factors and diet recommendations to patients should be reconsidered."
Risk factors for asymptomatic diverticulosis remain poorly defined, although many physicians and patients have considered high intake of dietary fiber and frequent bowel movements as protective, the authors wrote in their background comments.
Studies focusing on the relationship between a low-fiber diet and diverticulosis generally failed to address selection bias and confounding factors and to confirm the presence of diverticulosis, they continued. Similarly, studies of other purported risks -- such as constipation and high consumption of red meat and dietary fat -- have yielded weak supporting evidence.
To learn more about risk factors for asymptomatic diverticulosis, Sandler and colleagues examined data from a colonoscopy-based study that accumulated comprehensive data on diet, physical activity, and bowel habits.
Data for the analysis came from the Diet and Health Studies, which examined environmental and lifestyle factors associated with colorectal adenomas. Participants in three of the studies underwent colonoscopy, most often because of screening indications, family history of colorectal cancer or polyps, or occult bleeding.
The final analysis included 2,104 study participants, 878 of whom had diverticulosis. The remaining 1,226 participants served as a control group.
The authors found that 28% of the diverticulosis group had three or more diverticula, 40% had one or two, and 32% did not have diverticula quantified. Participants with diverticula were more likely to be older, overweight or obese, white, tobacco users, and NSAID users.
An adjusted analysis showed that the prevalence of diverticulosis increased in a linear manner with fiber intake.
Using the lowest quartile of fiber consumption as the reference, the authors found that the odds for diverticulosis increased to 1.03 in the second quartile, to 1.14 in the third, and to 1.30 in the fourth (P=0.004).
Comparing all participants with diverticulosis, the authors found that participants with three or more diverticula were significantly more likely to have the highest intake of dietary fiber (OR 1.81 versus the lowest quartile).
An analysis of the relationship of bowel habits to diverticulosis yielded a similarly linear relationship.
Compared with participants who had fewer than seven bowel movements weekly, those who had seven per week had a diverticulosis odds ratio of 1.34, increasing to 1.59 for eight to 14 weekly bowel movements, and to 1.70 for 15 or more (P<0.001).
Other factors commonly cited as potential risk factors did not have significant associations with diverticulosis, including total fat intake, consumption of red meat, and physical activity.
"We cannot exclude the possibility that people with diverticulosis had symptoms and changed their diet as a consequence," the authors wrote of their findings. "Although such a dietary modification would explain our findings, it is conventionally believed that diverticula do not cause symptoms.
"The mechanism for the formation of diverticula is unknown. The most widely accepted hypothesis, which we dispute, is that a high-fiber diet bulks the stools, increases colon diameter, and decreases intraluminal pressures ..."
"According to this hypothesis, high pressure and colonic segmentation cause the mucosa to herniate through weak areas in the wall to cause diverticula. However, the high-pressure/pulsion hypothesis would not explain right-sided diverticula ... where the bowel diameter is large and increased muscular contraction is not seen."

The study was supported by the National Institutes of Health.
The authors had no relevant disclosures.

Primary source: Gastroenterology
Source reference:
Peery AF, et al "A high-fiber diet does not protect against asymptomatic diverticulosis" Gastroenterology 2012; DOI: 10.1053/j.gastro.2011.10.035.

Black Tea Cuts Blood Pressure

By Todd Neale, Senior Staff Writer, MedPage Today MedPage Direct Link
Published: January 23, 2012
Reviewed by Dori F. Zaleznik, MD; Associate Clinical Professor of Medicine, Harvard Medical School, Boston and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

1 comment(s)

Action Points

• A randomized double-blind trial found a significant drop in both systolic and diastolic blood pressure in people consuming black tea for six months compared to those drinking a placebo containing caffeine but not black tea solids.
• Note that overall body mass index did not change during this trial period.

Regular consumption of black tea -- which is rich in flavonoids -- significantly reduced blood pressure, a randomized, placebo-controlled trial showed.

Drinking three cups each day for six months lowered both diastolic and systolic blood pressure by 2 to 3 mm Hg (P≤0.05), according to Jonathan Hodgson, PhD, of the University of Western Australia in Perth, and colleagues.

Even those small changes could have a large impact on health at the population level, they reported in a research letter in Archives of Internal Medicine.
Those differences would be associated with a 10% reduction in the prevalence of hypertension and a 7% to 10% decrease in the risk of cardiovascular disease, they said.
Hodgson and colleagues conducted a randomized trial that included 95 men and women ages 35 to 75 (mean age 56 for men and 57 for women) who were regular tea drinkers. The participants had a mean body mass index of 25 kg/m² and a mean daytime ambulatory systolic blood pressure of 121 mm Hg at baseline.
During a four-week run-in period, all of the participants consumed a low-flavonoid diet along with three cups of regular leaf tea per day.
During the six-month intervention period, the participants were randomized to three cups per day of either 1,493-mg powdered black tea solids that contained 429 mg of polyphenols and 96 mg of caffeine or a placebo drink matched in flavor and caffeine content.
From baseline to six months, there were no changes in energy and nutrient intake, urinary sodium and potassium excretion, or body weight in either group.
There were, however, differences in 24-hour ambulatory blood pressure, driven mostly by daytime readings.
For systolic, readings were 2.7 mm Hg lower at three months and 2.0 mm Hg lower at six months in the participants who were drinking tea.
For diastolic, the differences were 2.3 and 2.1 mm Hg, respectively.
Hodgson and colleagues noted that previous short-term randomized trials exploring the effects of black tea on blood pressure may have failed to demonstrate significant effects because they were underpowered to find small but clinically significant differences.
It is also possible, they noted, that longer-term consumption is needed to make an impact.
As for why black tea would lower blood pressure, the researchers pointed to effects on endothelial function.
Endothelial dysfunction may be an early marker for changes in blood pressure, and there is evidence that tea consumption improves endothelial function. Also, a previous study by Hodgson and colleagues showed that tea flavonoids affect nitric oxide status and reduce levels of endothelin.
"This could contribute to reduced vascular tone and lower blood pressure," the authors wrote.
Another possible mechanism involves the effects of tea flavonoids on body weight and visceral fatness.
"A recent meta-analysis suggests that green tea and its flavonoids -- many of which are structurally similar to black tea flavonoids -- together with caffeine can reduce body weight and abdominal fatness," wrote the researchers, who noted that, although there was no change in body weight in the current study, information on abdominal fatness was not available.

Funding for the study was provided by the National Health and Medical Research Council of Australia and Unilever Research and Development in Vlaardingen, the Netherlands.
The authors reported that they had no conflicts of interest.

Primary source: Archives of Internal Medicine
Source reference:
Hodgson J, et al "Effects of black tea on blood pressure: A randomized controlled trial" Arch Intern Med 2012; 172: 186-188.

Milk Powder Cuts Gout Flares

By Nancy Walsh, Staff Writer, MedPage Today MedPage Direct Link
Published: January 23, 2012
Reviewed by Zalman S. Agus, MD; Emeritus Professor
University of Pennsylvania School of Medicine and Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner

4 comment(s)

Action Points

• Observational studies have shown an inverse relationship between low-fat dairy intake and the risk of developing gout. This study evaluates this observation with a randomized, controlled trial.
• Point out that this study suggested that skim milk powder enriched with two dairy fractions reduces the frequency of gout flares in patients with recurrent episodes of gout.

Daily consumption of enriched skim milk powder could help prevent gout flares, a proof-of-concept study suggested.

Compared with patients randomized to receive control treatment with simple powdered lactose, those given enriched skim milk powder had greater reductions in flares of gout during a three-month period (P=0.044), according to Nicola Dalbeth, MD, of the University of Auckland in New Zealand, and colleagues.

However, there was no difference in flare frequency for patients given plain skim milk powder rather than the enriched formulation, compared with those given lactose (P=0.81), the researchers reported online in Annals of the Rheumatic Diseases.
Longitudinal observational studies have shown an inverse relationship between low-fat dairy intake and risk of developing gout. Previous work also has suggested that increased intake of skim milk or milk protein can help lower serum urate. Moreover, the specific fractions glycomacropeptide and G600 milk fat extract, used to enrich skim milk powder, have been shown to exert anti-inflammatory effects in a murine model.
"These agents may have reduced gout flares through inhibition of the inflammatory response to monosodium urate crystals present within the joint," the researchers explained.
To assess the potential of these milk fractions for limiting flares of gout, Dalbeth and colleagues enrolled 120 patients with inadequately controlled gout.
Participants' mean age was 56, and most were white men.
Slightly more than half were taking allopurinol (Zyloprim), and during the month prior to enrollment, the average number of flares was 1.5.
At baseline, the median intake of low-fat dairy was slightly over one serving per day.
The lactose control, skim milk control, and enriched skim milk treatments all were administered as daily vanilla-flavored shakes.
Aside from decreased frequency of flares, the enriched powder was associated with "clinically relevant endpoints," such as lower pain scores compared with lactose (P=0.048), the researchers reported.
There also was a significant increase in fractional uric acid excretion for the enriched skim milk group compared with both the lactose group (P=0.0002) and the plain skim milk group (P=0.020).
For tender joint counts, a trend was seen for improvements in the enriched group (P=0.066), but no differences were found for swollen joint counts.
Adverse events were similar in the three groups, being reported by about half of all participants.
Most of the events were gastrointestinal, such as nausea or diarrhea, occurring in 13% of the lactose group, 5% of the plain skim milk powder group, and 18% of the enriched milk powder group.
Serious adverse events included hospitalization for gout flare or falls, and were considered unrelated to the study treatment.
The active treatment was not associated with any changes in lipids or serum creatinine.
A small weight gain was seen in all three groups, being about one pound in the enriched powder group.
Diastolic blood pressure fell by 3.6 mm Hg in the enriched milk powder group, which differed significantly from the lactose group (P=0.001).
The researchers termed it "noteworthy" that patients taking plain skim milk powder -- in quantities equivalent to two additional servings of low-fat dairy per day -- had no benefit, in contrast to what has been seen in previous cross-sectional studies.
Current recommendations for diet in gout call for two extra portions of dairy, based on those earlier studies, so further randomized trials should be conducted to clarify the optimal quantity, they said.
The study was limited to a single center and a population with high rates of severe gout.
An additional limitation was that the two specific milk fractions included in the enriched formulation have not be evaluated separately or in different quantities.
"Future work will be directed at determining the effects of individual fractions and various combinations," the researchers said.

The study was funded by LactoPharma and the New Zealand Government Foundation for Research Science and Technology.
The lead author and two co-authors are named on a patent application for milk products to be used in gout, and three co-authors are employees of Fonterra Cooperative Group Ltd.

Primary source: Annals of the Rheumatic Diseases
Source reference:
Dalbeth N, et al "Effects of skim milk powder enriched with glycomacropeptide and G600 milk fat extract on frequency of gout flares: a proof-of-concept randomized controlled trial" Ann Rheum Dis 2012; DOI:10.1136/annrheumdis-2011-200156.

ACP workgroup compiles list of low-value tests

A workgroup of internists convened by ACP has developed a list of 37 clinical situations in which medical tests are commonly used but do not provide high value.
The list was developed by a consensus-based process and was published in the Jan. 17 Annals of Internal Medicine, with a goal of promoting thoughtful discussions about which tests and interventions promote high-value, cost-conscious care. The list includes a variety of inpatient and outpatient situations in which the experts felt use of a test may provide no benefit or be harmful, including several cardiac tests, cancer screens and diagnostic studies.
Some situations in which the workgroup unanimously concluded that a test does not reflect high-value care include:

• obtaining exercise electrocardiogram for screening in low-risk asymptomatic adults,
• screening for colorectal cancer in adults older than 75 years or in adults with a life expectancy of less than 10 years,
• performing preoperative chest radiography in the absence of a clinical suspicion for intrathoracic pathology,
• performing imaging studies in patients with nonspecific low back pain,
• performing brain imaging studies (CT or MRI) to evaluate simple syncope in patients with normal findings on neurologic examination, and
• performing imaging studies, rather than a high-sensitivity D-dimer measurement, as the initial diagnostic test in patients with low pretest probability of venous thromboembolism.

The workgroup also suggested some general principles for providing high-value care with testing. First, diagnostic tests usually should not be performed if the results will not change management. Second, in situations where the pre-test probability of disease is low, the likelihood of a false-positive could be higher than the likelihood of a true-positive, potentially leading to expensive and harmful further testing. Finally, when considering the cost of a test, downstream costs, such as follow-up testing, should be considered, the group said.
An editorial accompanying the article noted that some physicians will likely take issue with some of the items on the list and invited all readers of the article to take a brief Web survey to indicate their agreement or disagreement. The editorial also suggested a number of questions that physicians should ask themselves to determine whether a test will provide value, including whether the test results are available from another source, what effects giving or not giving the test are likely to have, and whether the test is being ordered primarily to reassure the patient.

Government Asks Court To Reconsider Bone Marrow Compensation Decision.

The Washington Post  (1/22, Barnes) reported that "the Obama administration last week asked a San Francisco appeals court to overturn a recent decision that said bone marrow donors can be paid for what their bodies produce." In December, "a unanimous three-judge panel...ruled for a nonprofit group, MoreMarrowDonors.org, that wants to encourage bone marrow donations by offering $3,000 scholarships, housing allowances or charitable donations to those who are matched with blood disease patients."

        "The Obama administration said the court was wrong to reach that conclusion and that paying for bone marrow could lead to an organ transplant market that favors the wealthy and exploits the sick and the poor," MedPage Today  (1/20, Walker) added. "The appeals judges argued that when Congress passed the National Organ Transplant Act, it wasn't taking into account the new method," which "removes bone marrow stem cells from a donor's bloodstream in a process similar to donating blood." But "in a petition filed Tuesday, US Attorney General Eric Holder requested that a full 11-judge panel rehear the case" saying that "the three judges were wrong in that interpretation and that the organ transplant law specifically classifies 'bone marrow' as 'the cells found in adult bone marrow and peripheral blood,' so the law was meant to ban payments for peripheral blood stem cell donations."

Having An Overweight Father May Increase Obesity Risk.

The Los Angeles Times  (1/21, Stein) "Booster Shots" blog reported, "Kids might be at higher risk for obesity if dad is overweight," according to a study in the International Journal of Obesity. Researchers studied "children from 3,285 two-parent families in Australia" and found that "having an overweight father and a healthy-weight mother increased the odds of the child becoming obese four years later by 318%," while "having a father who was obese increased the odds to 1,388%." Authors suggested that the study shows "the important role that fathers have in the development of children's weight status and this has consequences for their long-term health outcomes."

Men May Face Higher Risk Of Getting 32 Out Of 35 Cancers.

The Orlando Sentinel  (1/20, Jameson) reported, "Men are at higher risk of getting 32 out of 35 cancers, according to an international study, which further suggests that the greatest reason for the gap lies in biology." Researchers found that, "for 15 cancers, the risk for men is twice that for women." The study, published in the European Journal of Epidemiology, also found that "for five cancers -- larynx, hypopharynx, lip, bladder and Kaposi sarcoma -- men have a four-times greater risk."

Mild Dehydration May Have Adverse Effects On Women.

WebMD  (1/21, Mann) reported, "In a new study of 25 healthy women, mild dehydration dampened moods, increased fatigue, and led to headaches. ... Overall, women's mental ability was not affected by mild dehydration. But they did have an increase in perception of task difficulty and lower concentration." However, emergency medicine physician Robert Glatter, MD noted that "not everyone needs to drink this much water. 'People with congestive heart failure and people with certain kinds of kidney disease may want to limit their fluid intake, and should talk to their doctor about how much water they should drink.'" The research was published in the Journal of Nutrition.

Manganese May Protect Against Shiga Toxin.

Bloomberg News  (1/20, Lopatto) reported that Shiga, "a deadly toxin produced by certain kinds of E. coli, including those that caused an outbreak in Europe last year, can be combated using the element manganese, according to research" in Science. Shiga causes "severe diarrhea and kidney damage," and manganese protects against the toxin "by blocking the path the Shiga toxin takes to shut down the cell." Researchers found that "in a study, mice dosed with manganese were resistant to the poison" and that "manganese...protected cells against as much as 4,000 times the amount of that toxin required to cause death in the lab."

High (and very low) salt intake is linked to cardiovascular events, including death

JAMA 2011;306:2229-38 [Free full-text JAMA article PDF] [PubMed® abstract]

[EXCERPTS

 

Encouragement to eat less salt has been a common feature of public health advice in recent years, although guidelines disagree about the intake we should be aiming for. Many observers believe the lower the better, although a recent analysis identified a J shaped association between sodium excretion (as a proxy for intake) and cardiovascular events in high risk adults.

Those excreting 4-6 g of sodium a day had the lowest risk of cardiovascular events, including death from cardiovascular disease (15.2% (2148/14 156)). Risk was significantly higher in those who excreted more (>8 g: 24.1% (204/847); fully adjusted hazard ratio 1.49, 95% CI 1.28 to 1.75) or less (<2 g: 1.21, 1.03 to 1.43; 2-3 g: 1.16, 1.04 to 1.28) than this reference amount. Should agencies that recommend no more than 1.5 g a day rethink their advice?

Not yet, says a linked editorial (p 2262). We have good evidence from randomised trials that eating less salt protects cardiovascular health. There is always room for more trials, to fine tune the safe range, but the principle is established and shouldn’t be overturned by observational work, however powerful and sophisticated it is. The J shape looks convincing, but adults on the “upstick” at the lower end of the curve may be avoiding salt because they are already ill. Isolating the effects of salt from other dietary habits is another challenge for observational studies, says the editorial, and estimating sodium excretion from one early morning urine sample was a particular challenge for this one. Policy makers should stand firm for now.

Cite this as: BMJ 2011;343:d7549