“In general, from the perspective of overall health, healthcare utilization, and outcomes, the suggestion has been from some of the studies that greater religiosity, in terms of participation or spirituality, is typically associated with better health outcomes,” he said. “It hasn’t been particularly well studied with regard to cardiovascular disease or in relation to the whole spectrum of cardiovascular disease risk factors and atherosclerosis. Also, the way religiosity has been measured in the past has not necessarily captured all the dimensions that might be of interest.”

To heartwire, Lloyd-Jones said this study, a retrospective analysis of the Multi-Ethnic Study of Atherosclerosis (MESA), originated 18 months ago, when lead author Matthew Feinstein, then a first-year medical student, approached him about investigating links between religious involvement, spirituality, and prayer/meditation and cardiovascular morbidity and mortality. Feinstein, who is still a student at the Feinberg School of Medicine, had researched a similar topic for his college thesis.

“Our hypothesis going in was that we suspected religiosity might in fact be associated with somewhat better outcomes, that it might be a generally healthier population, or that there might something about spirituality itself that would potentially lead to better health profiles,” said Lloyd-Jones.

MESA: A rich data set

In the MESA cohort, which included 5474 white, black, Hispanic, and Chinese participants aged 45 to 84 years old, religiosity was based on participant responses to a questionnaire and was defined by three dimensions: frequency of religious participation, frequency of prayer and meditation, and spirituality. The Daily Spiritual Experiences Scale, a five-item scale designed to assess feelings of closeness to God or the transcendent and experiences that grow out of that closeness, was used to measure spirituality.

Overall, there was no consistent association between measures of religiosity and the presence of subclinical cardiovascular disease as measured by various tests, including coronary artery calcium measurements, carotid intima-media thickness scans, left-ventricular mass assessments, and ankle-brachial-index measurements. Similarly, there was no association between religiosity and cardiovascular disease events at four years.

There was, however, a consistent and significant association between religiosity and obesity. After adjustment for different variables, those who attended frequent religious services were more likely to be obese and less likely to smoke. Also, those with the highest levels of spirituality were significantly more likely to be obese and less likely to smoke. There were no other associations observed between religiosity, spirituality, and other risk factors such as diabetes, hypercholesterolemia, and diabetes.

Odds ratio for smoking and obesity by frequency of religious practice

Odds ratio for smoking and obesity by feelings of spirituality

“The obesity story is interesting, and we tried a lot of different ways to get it to go away—looking at social, demographic, and psychosocial factors—and really didn’t see any clear explanation for it,” said Lloyd-Jones. “So we’re left with this observation, and we’re not really sure what’s the cart and what’s the horse. We don’t really know if there is something about religious participation that leads to obesity, or if it’s the other way around, and that heavier people might seek out religious and spiritual experiences because of things like stigmatization.”

One of the strengths of the study is that it is more representative of different ethnicities, as well as men and women, than previous studies. However, more research still needs to be done, said Lloyd-Jones, adding that his group is currently conducting a long-term prospective study of religious involvement, spirituality, and cardiovascular risk factors and events. He said that they hope that this study will be able to better explain the association between obesity and religiosity. In the meantime, he said, these data are not likely to alter clinical practice.

“Certainly, as physicians, we don’t want to discourage anything that’s likely to be of support or is going to make a patient feel better,” he said. “These data don’t provide a clear indication one way or the other about whether we should make recommendations with regard to cardiovascular health. But these are very interesting data, and we’ll have to learn a little bit more about them in the research realm before we can make recommendations.”