Type D personality as a predictor of self-efficacy and social support in patients with type 2 diabetes mellitus

OBJECTIVE: The aim of this study was to estimate the prevalence of Type D personality and assess the relationship between this personality type and self-efficacy/social support in Chinese patients with type 2 diabetes mellitus (T2DM). PATIENTS AND METHODS: From January 1, 2014, to July 31, 2014, 532 consecutive patients with T2DM were recruited from two hospitals in Guangzhou, China. The participants completed questionnaires containing questions about sociodemographic characteristics, Type D personality, self-efficacy, and social support scales, and their medical records were reviewed for additional data. RESULTS: Of the 532 patients, 18.2% had Type D personality. Patients with this personality type reported significantly lower levels of self-efficacy (P<0.001), total social support (P<0.001), subjective support (P<0.001), and support utilization (P=0.003), but similar level of objective support (P=0.314), compared to those of patients without Type D personality. Negative affectivity and social inhibition, two intrinsic traits of Type D personality, negatively correlated with self-efficacy and social support scores. Type D personality was significantly associated with less self-efficacy and social support (P<0.001), controlling for other sociodemographic factors. Glycosylated hemoglobin (HbA1c) levels were significantly higher in T2DM patients with Type D personality than in patients with non-Type D personality. CONCLUSION: This study provides new evidence linking Type D personality with self-efficacy, social support, and poor glycemic control, highlighting the special need for care among T2DM patients with Type D personality.