Saturday, December 14, 2013

Diabetes Drugs Affect Men’s and Women’s Hearts Differently

Metformin had a favorable effect on cardiac metabolism in women but an unfavorable one in men, according to a study of 78 patients with type 2 diabetes. Adding rosiglitazone mitigated some of the negative effects of metformin in men, and improved heart metabolism further in women. Adding Lovaza (an omega-3 fish oil) improved diastolic function, particularly in men. The American Journal of Physiology – Heart and Circulatory Physiology studyused PET, echocardiography, and whole body tracer studies before and 3 months after randomization to metformin, metformin + rosiglitazone, or metformin + Lovaza.

Cisplatin Linked to Increased Acute Kidney Injury Risk

A study of 1721 Japanese cancer patients treated with cisplatin as a first-line chemotherapy between 2006 and 2012 found that cisplatin dosages/m² or diagnosis of stage 4 cancer were risk factors of moderate cisplatin-induced acute kidney injury (AKI). Patients with a history of diabetes, a history of cardiovascular disease, or a diagnosis of stage 4 cancer were risk factors for severe cisplatin-induced AKI. The Oncology study investigators note that because severe cisplatin-induced AKI can shorten survival, physicians should carefully consider whether the use of cisplatin will benefit patients with these risk factors.

Study finds CPAP may lead to reduced blood pressure in patients with sleep apnea and high blood pressure.

HealthDay (12/11, Reinberg) reports on a study published in the Journal of the American Medical Association finding that the treating of sleep apnea with the standard treatment of continuous positive airway pressure for 12 weeks led to reduced diastolic blood pressure and improved “overall nighttime blood pressure” among patients with sleep apnea who were “taking three or more drugs to lower their blood pressure.” Researchers recommended that patients with hard-to-control high blood pressure be tested for sleep apnea. The study covered 194 patients randomly assigned to CPAP or no CPAP. Those assigned to CPAP “lowered their 24-hour average blood pressure 3.1 mm Hg more than those not receiving CPAP,” and also had “a 3.2 mm Hg greater reduction in 24-hour average diastolic blood pressure.”

        Medscape (12/11, O'Riordan) reports the study found “significant improvements in their 24-hour mean and diastolic blood pressures, but no change in their systolic blood pressure.”

Study finds increased risk of B12 deficiency among long-term users of PPIs, H2RAs.

The New York Times (12/10, Saint Louis) reports on a study published in the Journal of the American Medical Association and conducted by researchers at Kaiser Permanente finding that proton-pump inhibitors and histamine 2 receptor antagonists “increase the risk of vitamin B12 deficiency.” That applies particularly to those patients who use the medications for two years or more. The study’s senior author Dr. Douglas A. Corley commented, “This raises the question of whether people taking these medications for long periods should be screened for vitamin B12 deficiency.” The study was based on the medical records of 25,956 adults diagnosed with vitamin B12 deficiency and 184,199 patients who did not have B12 deficiency during the period 1997-2011. Specifically, those “who took P.P.I’s for more than two years were 65 percent more likely to have a vitamin B12 deficiency” as 12 percent of those with B12 deficiency “had used P.P.I.’s for two years or more,” compared to “7.2 percent of control patients,” while 4.2 percent were “long-term” users of H2RA’s compared to “3.2 percent of nonusers.”

        The San Francisco Chronicle (12/11, Colliver) explains that B-12 deficiency is associated with greater “risk of dementia, nerve damage, anemia and other potentially serious medical problems.” Dr. Corley also pointed out that PPIs have been connected to “increased risk in food-borne infections and bone fractures” in earlier research “because these drugs make it difficult to absorb certain nutrients.” In response to the study, Dr. Keith Obstein, a gastroenterologist at Vanderbilt University Medical Center in Nashville and a committee member of the American College of Gastroenterology, said that “the study gives physicians another potential side effect to discuss with their patients.”

        Reuters (12/11, Seaman) reports that Dr. Corley said that those taking the medications should not simply stop, but that they “should have their B12 levels checked.” He also said that patients should take the smallest effective dose and for as little duration as possible. Reuters lists a number of PPIs omeprazole, esomeprazole, and lansoprazole, and H2RAs cimetidine, famotidine, and ranitidine.

        BBC News (12/11) reports that Prof Mark Pritchard of the British Society of Gastroenterology pointed out that “only a minority of patients” who were long-term users of the medications were also B12 deficient. The report found that higher doses led to greater likelihood of deficiency, and the link “was stronger in women and younger age groups,” but it also found that “the overall risk was still low.”

        HealthDay (12/11, Gordon) reports that last year, there were over “150 million prescriptions” for PPIs, while lower doses are available over the counter.

        MedPage Today (12/11, Petrochko) reports the population of those with B12 deficiency was “mostly female (57.4%), 60 or older (67.2%), and were white (68.4%).”

        NPR (12/11, Shute) also covered the study in its “Shots” blog.

Cancer Drug Linked with Decreased Kidney Function

Patients taking crizotinib for the treatment of non-small cell lung cancer experienced an average 23.9% decrease in eGFR during the first 12 weeks of therapy in a recent Cancer study. The study included 38 patients on crizotinib therapy, and their reduced kidney function was most evident in the first 2 weeks of treatment. When crizotinib therapy was stopped, 56% of patients had complete recovery in their eGFR. The renal effects of crizotinib, which blocks a protein made by the mutated anaplastic lymphoma kinase gene, may need to be considered when determining the appropriate duration of crizotinib therapy.

Sodium Restriction May Increase Efficacy of RAAS Blockade

In patients with nondiabetic CKD, sodium restriction on top of single and dual renin-angiotensin-aldosterone system (RAAS) blockade increases circulating levels of the anti-inflammatory and antifibrotic peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), according to a secondary analysis of a 46-patient randomized clinical trial. Patients with overt proteinuria and mild-to-moderate renal insufficiency were subjected to four double-blind 6-week study periods with either a regular-sodium or low-sodium diet in addition to either lisinopril or lisinopril plus valsartan. The Journal of Hypertension analysis concludes the rise in AcSDKP may contribute to the enhanced cardiorenal protection of RAAS-blockade during sodium restriction.

Nighttime Blood Pressure Linked with Increased Risk of Developing CKD

Nighttime blood pressure (BP) is a better CKD predictor than daytime BP according to a Journal of Hypertension studyof 843 individuals without CKD at baseline from the general Japanese population. Individuals with a 1–standard deviation (SD) increase in daytime systolic BP had a 13% increased risk of developing CKD over a median of 8.3 years. Those with a 1-SD increase in nighttime systolic BP had a 21% increased risk. When nighttime and daytime BP were mutually adjusted into the same model only nighttime BP persisted as an independent predictor of CKD.

Acute Kidney Injury May Be Deadlier Than Heart Attacks

Patients with acute kidney injury (AKI) or AKI and myocardial infarction (MI) later experienced more major heart and kidney problems than those with MI alone. A CJASN article analyzed 36,980 patients discharged with a diagnosis of AKI or myocardial infarction (MI) who were admitted to a VA facility between October 1999 and December 2005 and followed for a maximum of 6 years depending on the index hospitalization. Deaths occurred most often in patients who experienced both AKI and MI (57.5%), and least often in patients with uncomplicated admissions for MI (32.3%).

No Link between Diastolic Dysfunction and Mortality in Patients with Heart Failure and Kidney Disease

A new study has found that severe diastolic dysfunction does not appear to contribute to the increased mortality risk observed in heart failure patients with renal dysfunction. Researchers analyzed data pertaining to 669 patients in the EchoCardiography and Heart Outcome Study (ECHOS), evaluating whether eGFR was associated with mortality risk before and after adjustment for severe diastolic dysfunction. During a 7-year follow-up period, eGFR was associated with similar mortality risk before and after adjustment for severe diastolic dysfunction according to the BMC Nephrology article.

Higher BMI Linked with Early Kidney Function Decline in Young Adults

Higher BMI categories were associated with greater declines in kidney function in a 10-year study of 2839 black and white young adults with normal kidney function at baseline. Individuals with a BMI of 25.0 to 29.9 were 1.50 times more likely to experience rapid kidney function decline; those with a BMI between 30.0 and 39.9 were 2.01 times more likely; and those with a BMI of 40.0 or higher were 2.57 times more likely. After age 30, average kidney function was progressively lower with each increment in BMI. The findings are published in the American Journal of Kidney Diseases.

Study: Walking faster may prolong life.

The New York Times (12/4, Reynolds) “Well” blog reports a recent study published in PLoS One indicates middle-aged people can improve the benefits of walking for exercise by increasing their pace. According to Lawrence Berkeley National Laboratory statistician Paul T. Williams, “Our results do suggest that there is a significant health benefit to pursuing a faster pace,” as pushing one’s body “appears to cause favorable physiological changes that milder exercise doesn’t replicate.”

Research Links Morning Blood Pressure Surge and Glycemic Control in Diabetics

In a study of 50 patients with type 2 diabetes, poor glycemic control and insulin resistance were independently associated with the occurrence of morning blood pressure surge, which might be significantly associated with endothelial dysfunction. HbA1c and triglyceride correlated significantly and positively with morning blood pressure surge, and they correlated significantly and negatively with brachial artery flow-mediated dilation. The Diabetes Carefindings noted that morning blood pressure surge is known to be an independent predictor of cardiovascular events, but little is known about its association with glycemic control.

Energy drinks may cause serious increases in heart contraction rates.

On its website, CBS News (12/3) reports that research presented at the Radiological Society of North America annual meeting suggests that “energy drinks may cause serious increases in heart contraction rates within an hour of” consuming them.

        The Huffington Post (12/3) reports that investigators “recruited 18 healthy people – 15 men and three women – with an average age of 27.5 to undergo cardiac magnetic resonance imaging before drinking an energy drink containing 32 milligrams/100 milliliters of caffeine and 400 milligrams/100 milliliters of taurine.” One “hour after consuming the drinks, all the participants underwent cardiac MRI to see if energy drink consumption had any effect on heart function.” The investigators “found that the participants’ hearts had increased contraction rates – indicated by increased peak systolic strain in the heart’s left ventricle – after drinking the energy drinks.”

        The Los Angeles Times (12/3, Kaplan) “Science Now” blog reports that the investigators “also looked for changes in heart rate and blood pressure before and after volunteers consumed the energy drink, but the readings in both cases were essentially the same.”

        On its website, FOX News (12/3) reports that researcher Dr. Jonas Dörner, said, “There are concerns about the products’ potential adverse side effects on heart function, especially in adolescents and young adults, but there is little or no regulation of energy drink sales.”

        HealthDay (12/3, Thompson) reports that this “study raises concerns that energy drinks might be bad for the heart, particularly for people who already have heart disease, said Dr. Kim Williams, vice president of the American College of Cardiology.” According to Dr. Williams, “We know there are drugs that can improve the function of the heart, but in the long term they have a detrimental effect on the heart.”

Study: Hospital charges the largest driver of medical inflation

ABC World News reported on “outrageous hospital costs” and “expensive and wildly confusing bills.” The segment focuses on one women who had the same tests performed at two different facilities and then received bills asking her to pay very different amounts. ABC’s Rebecca Jarvis said, “With so many hospitals, doctors, labs and insurance companies negotiating rates confidentially among themselves, patients are at their wits end.”

        In a 3,500-word story front-page story titled, “As Hospital Prices Soar, A Single Stitch Tops $500,” the New York Times (12/3, Rosenthal, Subscription Publication) also reports on high hospital costs and hospitals’ often confusing billing patterns. The “prices for any item or service are set by each hospital and move up and down yearly, and show extraordinary variability, health economists say.” The primary cause of “high hospital costs in the United States, economists say, is fiscal, not medical: Hospitals are the most powerful players in a health care system that has little or no price regulation in the private market.” The article points out that “hospital charges represent about a third of the $2.7 trillion annual United States health care bill, the biggest single segment, according to government statistics, and are the largest driver of medical inflation, a new study in The Journal of the American Medical Association found.” The Times also discusses how emergency departments have, in many cases, become “profit centers.”

        Reuters (12/3, Jegtvig) reports that patients often have no idea how much a medical procedure costs until they have been discharged from the hospital, and a study published online in JAMA Internal Medicine indicates that it would be difficult to find out beforehand. Investigators attempting to obtain price quotes for an electrocardiogram from hospitals in the Philadelphia area. The researchers found that just three of the 20 hospitals provided a quote on how much the test would cost.

Study: “Healthy obesity” does not exist.

NBC Nightly News reported that new research suggests that individuals cannot be simultaneously be overweight and physically fit. NBC’s Chief Medical Editor Dr. Nancy Snyderman said that the research indicates that “there is no such thing as healthy obesity.”

        Reuters (12/3, Pittman) reports that investigators analyzed data from studies that included a total of more than 61,000 participants.

        The Los Angeles Times (12/3, Healy) “Science Now” blog reports that the investigators “found that, as BMI rose, so rose blood pressure, waist circumference and insulin resistance.” Meanwhile, “as BMI increased, levels of HDL cholesterol, thought to protect against heart attack and stroke, decreased.” While participants who were either overweight or obese “may not yet have reached the points that define metabolic illness, they appeared to be on that road as their weight” increased. The research was published online in the Annals of Internal Medicine.

        On its website, Time (12/3, Sifferlin) reports that “since obesity has different effects on the body for different people, researchers are still investigating how weight gain and its health effects may vary among people whose obesity is due primarily to things such as genetics and environmental exposures as opposed to unhealthy diets and lack of physical activity.” The article points out that some of the studies used “in the current meta-analysis” had no “follow-up with the participants, so the final mortality and heart disease rates may be slightly higher or lower than they should be.”

        On its website, NBC News (12/3, Carroll) reports that the findings appear “to contradict a study published earlier this year, which had concluded that overweight individuals might actually be healthier than those with normal weights,” although “the differing results may simply be due to the fact that the new report looked at different data and at long-term outcomes, experts said.” Also covering the story are HealthDay (12/3, Reinberg), MedPage Today (12/3, Boyles), and Medscape (12/3, Laidman).