Although personality traits may contribute to risk for cardiovascular disease (CVD), inconsistent findings have prompted efforts to refine their measurement to include only the hostile and aggressive components. Data are sparse on the "social avoidance" (SA) subscale that measures more indirectly negative traits such as shyness. Thus, we sought to examine the association between SA and CVD, coronary heart disease (CHD), and non-CVD death.
A total of 2107 men (ages 40-55 years) free of baseline CVD were enrolled in 1957 in the Western Electric Study. SA was measured at study entry using the four-item subscale of the Cook-Medley hostility scale to divide the cohort into four groups according to the degree of social avoidance. CHD mortality, CVD mortality, and non-CVD mortality were determined by death certificate.
After 30 years of follow-up, SA was associated with CVD mortality for the highest vs. the lowest SA group in age-adjusted models (hazard ratio 1.39; 95% confidence interval [95% CI] 1.04-1.84) and after adjustment for traditional CVD risk factors (hazard ratio 1.49; 95% CI 1.12-2.00). After further adjustment for measures of hostility, the findings were similar. Findings for CHD mortality were similar. However, there was no significant association between SA and non-CVD mortality.
Social avoidance is associated with CVD mortality but not with non-CVD mortality in middle-aged men. These findings suggest the hypothesis that social avoidance might promote CVD through physiologic, non-behavioral mechanisms.