Ample evidence suggests that social support, self-efficacy, and adherence significantly, independently, and together affect glycemic control in patients with type 2 diabetes mellitus (T2DM), but the pathway from social support to glycemic control remains unclear. This study hypothesized that the effect of social support on glycemic control was mediated sequentially by self-efficacy and adherence. Patients with T2DM were recruited from two hospitals in Guangzhou, China, from January 1 to July 31, 2014, and their sociodemographic clinical data and their assessments on social support, self-efficacy, and adherence were obtained from medical records and self-completed questionnaires. Of the 532 patients who participated, 35% achieved glycemic control (i.e., HbA1c < 7%). Social support, self-efficacy, and adherence had significant correlations with each other and with glycemic control (P < 0.05). Regression analyses and structural equation modeling showed that better social support was associated to better patient self-efficacy, which, in turn, was associated with better medical adherence, which was associated with improved glycemic control, and the relationship between social support and glycemic control was sequentially and completely mediated by self-efficacy and adherence. The five goodness-of-fit indices confirmed that our data fitted the hypothesized pathway model strongly.

ObjectiveThe 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 methodsFrom 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.ResultsOf 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.ConclusionThis 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.