Pl. Graves et al., TEMPERAMENT AS A POTENTIAL PREDICTOR OF MORTALITY - EVIDENCE FROM A 41-YEAR PROSPECTIVE-STUDY, Journal of behavioral medicine, 17(2), 1994, pp. 111-126
Psychological factors were hypothesized to influence mortality, in par
ticular, early versus later mortality. To explore the relationship bet
ween temperament, a psychological factor, and mortality in a prospecti
ve study of 1337 medical students, we constructed a measure portraying
three temperament types, using latent class analysis. Death occurred
in 113 subjects over 25-41 years of follow-up. In univariate survival
analysis, subjects tending to direct tension ''inward'' when under str
ess (''Tension-In'') had a higher risk of mortality than ''Tension-Out
'' or ''Stable'' types. These associations persisted after adjustment
for age, smoking, cholesterol level, and Quetelet Index. The relative
risk (RR) of mortality for Tension-In was 1.56 (95% confidence interv
al, 1.00-2.44) compared with the Stable group. The risk was due 'entir
ely to the excess risk in persons under 55 years of age (RR, 2.59; 95%
confidence interval, 1.46-4.62); the corresponding risk of death in o
lder persons was 0.66 (0.30-1.48). Thus temperament is a significant r
isk factor for mortality, in particular, premature death.