Objective: Trait anger has been shown to predict coronary heart disease; however, there are no prior studies evaluating anger as a risk factor for type 2 diabetes. The objective of this study was to determine if anger proneness predicted type 2 diabetes using prospective analyses.
Methods: We analyzed data on trait anger, assessed by questionnaire, in a longitudinal, bi-racial cohort study of 11,615 initially non-diabetic adults aged 48-67, who were subsequently followed for 6 years for the development of type 2 diabetes.
Results: There was no relation between overall trait anger and the subsequent risk of diabetes; however, individuals in the highest tertile of trait anger temperament scores had a 34% increased risk of developing diabetes compared to those in the lowest tertile (Relative hazard [RH] = 1.34; 95% confidence interval: 1.10, 1.62), following adjustment for age, race, gender, and education. The relation between anger temperament and diabetes remained significant following adjustment for behavioral factors (smoking, physical activity, and caloric intake) (RH = 1.31; 95% CI: 1.08, 1.60) but was non-significant after additional adjustment for waist-to-hip ratio and body-mass index (RH = 1.18; 95% CI: 0.97, 1.44).
Conclusions: While we found no relation between overall trait anger and incident diabetes, persons who had higher anger temperament subscale scores had a slightly increased risk of type 2 diabetes, which was largely explained by adiposity. Anger temperament may deserve further attention as a potential risk factor for type 2 diabetes.