Association of Religious Service Attendance With Mortality Among Women

Abstract

Importance: Studies on the association between attendance at religious services and mortality often have been limited by inadequate methods for reverse causation, inability to assess effects over time, and limited information on mediators and cause-specific mortality.

Objective: To evaluate associations between attendance at religious services and subsequent mortality in women.

Design, setting, and participants: Attendance at religious services was assessed from the first questionnaire in 1992 through June 2012, by a self-reported question asked of 74 534 women in the Nurses' Health Study who were free of cardiovascular disease and cancer at baseline. Data analysis was conducted from return of the 1996 questionnaire through June 2012.

Main outcomes and measures: Cox proportional hazards regression model and marginal structural models with time-varying covariates were used to examine the association of attendance at religious services with all-cause and cause-specific mortality. We adjusted for a wide range of demographic covariates, lifestyle factors, and medical history measured repeatedly during the follow-up, and performed sensitivity analyses to examine the influence of potential unmeasured and residual confounding.

Results: Among the 74 534 women participants, there were 13 537 deaths, including 2721 owing to cardiovascular deaths and 4479 owing to cancer deaths. After multivariable adjustment for major lifestyle factors, risk factors, and attendance at religious services in 1992, attending a religious service more than once per week was associated with 33% lower all-cause mortality compared with women who had never attended religious services (hazard ratio, 0.67; 95% CI, 0.62-0.71; P < .001 for trend). Comparing women who attended religious services more than once per week with those who never attend, the hazard ratio for cardiovascular mortality was 0.73 (95% CI, 0.62-0.85; P < .001 for trend) and for cancer mortality was 0.79 (95% CI, 0.70-0.89; P < .001 for trend). Results were robust in sensitivity analysis. Depressive symptoms, smoking, social support, and optimism were potentially important mediators, although the overall proportion of the association between attendance at religious services and mortality was moderate (eg, social support explained 23% of the effect [P = .003], depressive symptoms explained 11% [P < .001], smoking explained 22% [P < .001], and optimism explained 9% [P < .001]).

Conclusions and relevance: Frequent attendance at religious services was associated with significantly lower risk of all-cause, cardiovascular, and cancer mortality among women. Religion and spirituality may be an underappreciated resource that physicians could explore with their patients, as appropriate.

Figure 1. Cumulative incidence for all-cause mortality and religious services attendance in the Nurses’ Health Study, 1996–2012

Hazard ratio = 0.67 (95% CI: 0.62–0.71) Multivariable model adjusted for age (continuous), alcohol consumption (none, 0.1–4.9, 5.0–14.9, ≥15.0 g/d), physical exercise (metabolic equivalent hours per week; quintiles), multivitamin use (yes, no), hypertension (yes, no), hypercholesterolemia (yes, no), type 2 diabetes (yes, no), depression (yes, no), menopausal status (premenopausal, postmenopausal) and post-menopausal hormone use (never, past and current), physical exam in the past 2 years (no, yes for symptoms and yes for screenings), healthy eating score (quintiles), smoking status (never, former, current), pack-years (<10, 10–19, 20–39, ≥40 pack-years for former smokers; <25, 25–44, 45–64, ≥65 pack-years for current smokers), and BMI (kg/m²; <21, 21–22.9, 23–24.9, 25–27.4, 27.5–29.9, 30–34.9, ≥35), husband’s education (less than high school, some high school, high school graduate, college, graduate school), good physical or function (yes, no), social integration score (quartiles), live alone (yes, no), median family income (continuous, dollars per year), geographic region (north, south, west, other), and religious service attendance in 1992 (never, < 1/week, ≥ 1/week). Social integration score, including score and frequency of relatives and friends were derived based on the definition from Am J Epidemiol 1979;109:186–204. For adjustment, we derived social integration score without religious service attendance components. P trend <0.0001 for Cox model