OBJECTIVE To determine whether type A behavior predicts all-cause mortality and incident coronary artery disease (CAD) in a type 1 diabetic population.
RESEARCH DESIGN AND METHODS Follow-up data (22 years) from the Pittsburgh Epidemiology of Diabetes Complications (EDC) study of childhood-onset type 1 diabetes were analyzed for the 506 participants who completed the Bortner Rating Scale (measuring type A behavior) and Beck Depression Inventory (BDI) at baseline (1986–1988). CAD comprised myocardial infarction as determined by hospital records/Q waves on electrocardiogram (ECG), CAD death (determined by a mortality classification committee), angiographic stenosis, ischemic ECG, and angina.
RESULTS There were 128 deaths (25.3%) during follow-up. Univariate analysis showed an inverse relationship between Bortner scores and all-cause mortality (P = 0.01), which remained significant after allowing for age, sex, duration, HbA1c, education, smoking, BMI, and physical activity (P = 0.03). However, the addition of BDI scores attenuated the relationship (P = 0.11) with a significant interaction (P = 0.03) such that any protective effect against mortality was limited among individuals with lower BDI scores (bottom three quintiles) (P = 0.07), whereas no effect was seen in those with higher BDI (P = 0.97). Bortner scores showed only a borderline association with incident CAD (P = 0.09).
CONCLUSIONS Those with higher type A behavior have lower all-cause mortality in our type 1 diabetic population, an effect that interacts with depressive symptomatology such that it is only operative in those with low BDI scores. Further research should focus on understanding this interaction.
- Received January 31, 2013.
- Accepted April 29, 2013.
- © 2013 by the American Diabetes Association.
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details.