Religion, Spirituality and Risk of Coronary Heart Disease: A Matched Case-Control Study and Meta-Analysis.

Although the association between religion/spirituality (R/S) and psychological outcomes is well established, current understanding of the association with cardiovascular disease remains limited. We sought to investigate the association between Islamic R/S and coronary heart disease (CHD), and place these findings in light of a meta-analysis. In this case-control study, 190 cases with non-fatal CHD were identified and individually matched with 383 hospital-based controls. R/S was measured by self-administered 102 items questionnaire. A tabular meta-analysis was performed of observational studies on R/S (high level versus low level) and CHD. In addition, a dose-response meta-analysis was conducted using generalized least-squares regression. Participants in the top quartile had decreased odds of CHD comparing to participants in the lowest quartile of religious belief (OR 0.20, 95% confidence interval (CI) 0.06-0.59), religious commitment (OR 0.36, CI 95% 0.13-0.99), religious emotions (OR 0.39, CI 95% 0.18-0.87), and total R/S score (OR 0.30, CI 95% 0.13-0.67). The meta-analysis study showed a significant relative risk of 0.88 (CI 95% 0.77-1.00) comparing individuals in high level versus low level of R/S. In dose-response meta-analysis, comparing people with no religious services attendance, the relative risks of CHD were 0.77 (CI 95% 0.65-0.91) for one times attendance and 0.27 (CI 95% 0.11-0.65) for five times attendance per month. R/S was associated with a significantly decreased risk of CHD. The possible causal nature of the observed associations warrants randomized clinical trial with large sample size.