Potential influence of Type A personality on plasma C-reactive protein levels in people with diabetes

Type A personality, although classically known as a factor linked to increased vascular risk, has recently been associated with increased survival in patients with diabetes. As low-grade inflammation predicts a poor outcome, the present study explored the potential associations between Type A and plasma levels of C-reactive protein (CRP) in diabetes.

Type A personality was assessed by the Bortner questionnaire in people with diabetes. The association between Type A and plasma CRP levels was examined by multivariable linear regression, and structural equation modelling (SEM) was performed to determine the impact of the major clinical, biological and psychological confounders.

The study included 626 participants with type 1 and type 2 diabetes from the Diabetes and Psychological Profile study. Multivariable analyses showed an independent inverse association between Type A score and CRP levels. The structural model adjusted for age, gender, diabetes type and duration, body mass index (BMI), smoking status, alcohol abuse, oral antidiabetic and statin treatments, HbA1c levels, lipids, perceived stress, anxiety and depression revealed significant associations between CRP and Type A (β=-0.135, 95% CI: -0.242, -0.028; P=0.014), BMI (β=0.194, 95% CI: 0.038, 0.350; P=0.015) and HDL cholesterol (β=-0.132, 95% CI: -0.245, -0.020; P=0.014).

Our present study data indicate that Type A personality is independently associated with lower CRP levels. This lower level of inflammation might explain the better clinical outcomes associated with Type A personality in patients with diabetes.