Meta-analyses of prospective studies on coronary heart disease, type A personality, and hostility.

BACKGROUND

Several large-scale prospective studies have failed to find an association between Type A personality (TAP) or hostility and coronary heart disease (CHD). The existing meta-analyses on this topic have several shortcomings, such as a selective search of the literature, the failed use of effect sizes, and methodological flaws.

METHODS

The present meta-analyses cover all prospective studies until the end of 1998. The correlation coefficient r is used as effect size to yield information on the population effect size R and variance. Several analyses have been carried out to stratify for disease endpoints, samples (healthy population, CHD patients), and methods used to determine TAP or hostility.

RESULTS

The population effect size (weighted average of all correlation coefficients) for TAP and CHD is R=0.003 (n=74,326, P=0.213), and for hostility and CHD R=0.022 (n=15,038, P=0.003).

CONCLUSIONS

The population effect size for TAP and CHD is not significant. Hostility yields a significant association with CHD; however, the effect size is so low that it has as yet no practical meaning for prediction and prevention.