Type A behavior pattern was associated with a relative risk of 1.9 (P=0.0006) and 2.1 (P=0.0015) for incident coronary heart disease compared to Type B men aged 39-49 and 50-59 years, respectively.
Cohort (n=3,154)
Yes
Does Type A behavior pattern increase the risk of incident coronary heart disease compared to Type B behavior in initially well men?
Type A behavior pattern is significantly associated with an approximately twofold increased risk of incident coronary heart disease in men, independent of traditional Framingham risk factors.
Effect estimate: RR 1.9 and 2.1
p-value: p=0.0006 and 0.0015
The Western Collaborative Group Study (WCGS) is a prospective epidemiological study of 3,154 initially well men, aged 39059 years at intake in 1960-61, who were employed in ten participating companies in California. Clinical coronary heart disease (CHD) occurred in 257 men during a follow-up period of eight and one-half years. Coronary heart disease risk is predicted using the additive multiple logistic model with the risk factors: age, cholesterol, systolic blood pressure, hematocrit, ECG status, smoking at intake, and relative body weight. The predicted individual CHS risk levels, using the logistic results derived from the WCGS data, are highly correlated with predicted risk levels using a Framington study (FS) equation for these same risk factors with 12-year follow-up. The observed number of CHS events in the WCGS is not significantly different from the expected number of events derived from the FS logistic equation, after correction of length of follow-up. Multiple logistic analysis of the direct association between CHD incidence and behavior pattern gives an approximate relative risk of 1.9 (P = 0.0006) and 2.1 (P = 0.0015) for Type A compared to Type B men aged 39-49 and 50-59 years, respectively. It is estimated that removal of the excess risk associated with Type A behavior would correspond to a 31% (standard error = 6.6%) reduction of coronary heart disease incidence in the Western Collaborative Group Study population.
Brand et al. (Sun,) conducted a cohort in Coronary heart disease (n=3,154). Type A behavior pattern vs. Type B behavior pattern was evaluated on Clinical coronary heart disease incidence (RR 1.9 and 2.1, p=0.0006 and 0.0015). Type A behavior pattern was associated with a relative risk of 1.9 (P=0.0006) and 2.1 (P=0.0015) for incident coronary heart disease compared to Type B men aged 39-49 and 50-59 years, respectively.