(Press-News.org) In a multiethnic group of adults, low serum 25-hydroxyvitamin D concentration was associated with increased risk of coronary heart disease events among white or Chinese participants but not among black or Hispanic participants, results that suggest that the risks and benefits of vitamin D supplementation should be evaluated carefully across race and ethnicity, according to a study in the July 10 issue of JAMA.
"Low circulating concentrations of 25-hydroxyvitamin D (25[OH]D) have been consistently associated with increased risk of clinical and subclinical coronary heart disease (CHD). Whether this relationship is causal and modifiable with vitamin D supplementation has not yet been determined in well-powered clinical trials, which are ongoing," according to background information in the article. "Most studies of 25(OH)D and risk of CHD have examined populations that are composed largely or entirely of white participants. Results from these studies are frequently extrapolated to multiracial populations. This may not be appropriate because vitamin D metabolism and circulating 25 (OH)D concentrations vary substantially by race/ethnicity."
Cassianne Robinson-Cohen, Ph.D., of the University of Washington, Seattle, and colleagues examined the association of serum 25(OH)D concentration with incident CHD events in a large, community-based, multiethnic population of adults. The analysis included 6,436 participants in the Multi-Ethnic Study of Atherosclerosis (MESA), recruited from July 2000 through September 2002, who were free of known cardiovascular disease at the beginning of the study. Serum 25(OH)D concentrations were measured at baseline and associations of 25(OH)D with adjudicated CHD events were assessed through May 2012. Adjudicated CHD event was defined as myocardial infarction (heart attack), angina, cardiac arrest, or CHD death.
At the beginning of the study, the average age was 62 years and 53 percent of participants were women. Average serum 25(OH)D concentrations varied substantially by race/ethnicity. During a median (midpoint) follow-up of 8.5 years, 361 participants had a CHD event.
The researchers found significant heterogeneity in the association of 25(OH)D with CHD risk by race/ethnicity. Lower serum 25(OH)D concentration was associated with significantly higher risks of CHD among white participants (26 percent higher risk) per 10 ng/mL decrement in 25(OH)D concentration and Chinese participants (67 percent higher risk). "However, there was no evidence of association among black participants or Hispanic participants."
"Differences in associations across race/ethnicity groups were consistent for both a broad and restricted definition of CHD and persisted after adjustment for known CHD risk factors," the authors write.
"Well-powered clinical trials are needed to determine whether vitamin D supplements have causal and clinically relevant effects on the risk of CHD. Currently, at least 5 such trials are under way. One of these trials, the Vitamin D and Omega-3 Trial (VITAL), is targeting enrollment of a large multiracial study population, although power may be insufficient to determine whether effects vary by race even in this trial. Our study suggests that the risks and benefits of vitamin D supplementation should be evaluated carefully across race and ethnicity, and that the results of ongoing vitamin D clinical trials should be applied cautiously to individuals who are not white."
(JAMA. 2013;310(2):179-188; Available pre-embargo to the media at http://media.jamanetwork.com)
Editor's Note: This study was supported by grants from the National Heart, Lung, and Blood Institute. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, etc.
Editorial: Race/Ethnicity, Serum 25-Hydroxyvitamin D, and Heart Disease
In an accompanying editorial, Keith C. Norris, M.D., of the University of California, Los Angeles, and Sandra F. Williams, D.M.D., M.D., of the Cleveland Clinic, Weston, Fla., write that "… this large, well-designed, multiethnic study adds important insights to the complex relationships among race/ethnicity, 25(OH)D concentrations, and CHD risk."
"The heterogeneity of the findings underscores the importance of exploring racial differences in clinical research and of not immediately generalizing results from ethnically homogeneous populations to other groups that may differ by race/ethnicity, sex, or age. Although the pooled data demonstrated a significant association between 25(OH)D and CHD, the subgroup analyses revealed marked differences underscoring the importance of examining such cohorts by race/ethnicity and thereby potentially discovering sociocultural or biological mediators that may affect cardiovascular health."
(JAMA. 2013;310(2):153-154; Available pre-embargo to the media at http://media.jamanetwork.com)
Editor's Note: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr. Norris reports receiving grant support from the National Institutes of Health; and payment for lectures and consulting from Abbott, Amgen, Davita, and Takeda. Dr. Williams reported no disclosures.
### END
Association of low vitamin D levels with risk of CHD events differs by race, ethnicity
2013-07-10
ELSE PRESS RELEASES FROM THIS DATE:
Rates of major CV procedures differ between Medicare Advantage and fee-for-service beneficiaries
2013-07-10
In a study that included nearly 6 million Medicare Advantage and Medicare fee-for-service beneficiaries from 12 states, rates of angiography and percutaneous coronary interventions were significantly lower among Medicare Advantage beneficiaries and geographic variation in procedure rates was substantial for both payment types, according to a study in the July 10 issue of JAMA.
"Treatment of cardiovascular disease is one of the largest drivers of health care cost in the United States, accounting for $273 billion annually. Cardiovascular procedures are major contributors ...
Soy protein supplementation does not reduce risk of prostate cancer recurrence
2013-07-10
Among men who had undergone radical prostatectomy, daily consumption of a beverage powder supplement containing soy protein isolate for 2 years did not reduce or delay development of biochemical recurrence of prostate cancer compared to men who received placebo, according to a study in the July 10 issue of JAMA.
"Prostate cancer is the most frequently diagnosed malignancy and the second most frequent cause of male cancer death in the United States and other Western countries but is far less frequent in Asian countries. Prostate cancer risk has been inversely associated ...
Research examines differences in rates of cardiac catheterization between New York State and Ontario
2013-07-10
The increased use of cardiac catheterization in New York relative to Ontario appears related to selecting more patients at low risk of obstructive coronary artery disease, with the subsequent diagnostic yield (i.e., the proportion of tested patients in whom disease was diagnosed) of this procedure in New York significantly lower than in Ontario, according to a study in the July 10 issue of JAMA.
"The continuing increase in health care expenditures is threatening the sustainability of the health care system and the economy of many developed countries. Debates among the ...
Dual antiplatelet therapy following coronary stent implantation is associated with improved outcomes
2013-07-10
Emmanouil S. Brilakis, M.D., Ph.D., of the VA North Texas Health Care System and University of Texas Southwestern Medical Center at Dallas, and colleagues conducted a review of medical literature regarding optimal medical therapy after percutaneous coronary intervention (PCI; procedures such as balloon angioplasty or stent placement used to open narrowed coronary arteries). The researchers identified 91 studies for inclusion in the review.
"Percutaneous coronary intervention is commonly performed for coronary revascularization in patients with stable angina or acute coronary ...
Improvement needed of prescription drug postmarketing studies
2013-07-10
"Because rare but potentially serious adverse events of prescription drugs are often discovered only after market approval, observational postmarketing studies constitute an important part of the U.S. drug safety system," write Kevin Fain, J.D., M.P.H., of the Johns Hopkins Bloomberg School of Public Health, Baltimore, and colleagues. "In 2007, Congress passed the Food and Drug Administration Amendments Act (FDAAA), which authorized the FDA to require postmarketing studies for a prescription drug's approval and mandate adherence to study deadlines. We examined how fulfillment ...
Biceps bulge, calves curve, 50-year-old assumptions muscled aside
2013-07-10
The basics of how a muscle generates power remain the same: Filaments of myosin tugging on filaments of actin shorten, or contract, the muscle – but the power doesn't just come from what's happening straight up and down the length of the muscle, as has been assumed for 50 years.
Instead, University of Washington-led research shows that as muscles bulge, the filaments are drawn apart from each other, the myosin tugs at sharper angles over greater distances, and it's that action that deserves credit for half the change in muscle force scientists have been measuring.
"The ...
Japan, China and South Korea account for 84 percent of the macroalgae patents
2013-07-10
The algae, traditionally cultivated for the food sector, are accessible marine resources as they grow in coastal areas. These crops increase by 7.5% on average every year and have become an important part of marine aquaculture through the diversification of demand for products based on macroalgae for bioenergy, cosmetics and biomedicine.
This and other conclusions are deduced from a study led by the Spanish National Research Council (CSIC) that delves into the distribution of applications and products patents derived from macroalgae among countries all around the world. ...
Research suggests Madagascar no longer an evolutionary hotspot
2013-07-10
Madagascar has long been known as a hotspot of biodiversity. Although it represents only one percent of the earth's area, it is home to about three percent of all animal and plant species on the planet. But research suggests the island's heyday of species development may be all but over.
"A staggering number of species are found only on Madagascar," said Daniel Scantlebury, a Ph.D. student in biology, "but this research shows there are limits to the number of species the island can sustain, and Madagascar may currently be at those limits."
Scantlebury's paper is being ...
Penn study shows vascular link in Alzheimer's disease with cognition
2013-07-10
PHILADELPHIA – Researchers in the Perelman School of Medicine at the University of Pennsylvania found that, across a variety of neurodegenerative diseases, cerebrovascular disease affecting circulation of blood in the brain was significantly associated with dementia. The researchers contend that people already exhibiting clinical features of Alzheimer's disease and other memory impairments may benefit from effective therapies currently available to reduce vascular problems. Thus, early management of vascular risk factors, such as high blood pressure and cholesterol, and ...
School policies reduce student drinking -- if they're perceived to be enforced
2013-07-10
"Just say no" has been many a parent's mantra when it comes to talking to their children about drugs or alcohol. Schools echo that with specific policies against illicit use on school grounds. But do those school policies work?
University of Washington professor of social work Richard Catalano and colleagues studied whether anti-alcohol policies in public and private schools in Washington state and Australia's Victoria state were effective for eighth- and ninth-graders.
What they found was that each school's particular policy mattered less than the students' perceived ...