A moderator-mediator analysis of coronary heart disease mortality

The purpose of this study is to better understand how risk factors for coronary heart disease (CHD) mortality may interact.

We conducted a moderator-mediator analysis of a representative national sample of 5027 and 2902 community-dwelling women and men in the first National Health and Nutrition Examination Survey free of CHD in 1982. The outcome was 10-year CHD mortality.

Two hundred sixty-seven subjects experienced CHD mortality. In the complete sample, gender moderated the effect of depressive symptoms, and among women, race-ethnicity moderated the effect of nonleisure activity on CHD mortality, defining three subgroups for further analysis: men, white women, and black/other women. Among men, baseline differences from median age (55 to 64 years), systolic blood pressure (129 to 158 mmHg), or self-rated general health ("good" to "poor") were associated with equivalent increases in 10-year CHD mortality from 2.3% to 5.3% [area-under-the-curve effect size (ES)=0.53]. These factors appeared to mediate the effect of education on CHD mortality. Severe depression in men was associated with higher 10-year CHD mortality than less or no depression, 10.0% vs. 2.5% (ES=0.55). Among white women, baseline differences from median age (51 to 65 years) was also associated with 10-year mortality (1.2 to 13.4%, ES=0.56), as was higher blood pressure (125 to 151 mmHg) or worse self-rated health ("very good" to "fair") to a lesser extent (1.2% to 3.5%, ES=0.51).

Moderators (gender, race-ethnicity) defined possible pathways to CHD mortality characterized by varying factors and interactions between factors, highlighting potential utility for targeted interventions among community-dwelling persons.