Cyclothymic Temperament is Associated with Poor Medication Adherence and Disordered Eating in Type 2 Diabetes Patients: A Case–Control Study

INTRODUCTION: Poor medication adherence and disordered eating are major self-care problems in patients with type 2 diabetes that worsen glycemic control and increase the risk of developing severe diabetes complications. Affective temperament, which remains mostly unchanged throughout life, is speculated to predict poor treatment response and high comorbidity. The aim of this study was to explore the link between affective temperament and poor glycemic control due to insufficient self-care. METHODS: This single-center case–control study involved 77 outpatients divided into the ‘poor glycemic control’ group (n = 52) and the ‘better glycemic control’ group (n = 25) based on their mean glycated hemoglobin (HbA1c) levels over the past 12 months. All participants underwent one-on-one interviews during which they completed the following psychometric questionnaires: (1) the Mini-International Neuropsychiatric Interview 5.0.0; (2) the Temperament Evaluation of Memphis, Pisa, and San Diego Auto-questionnaire; (3) a researcher-designed single question for assessing subclinical stress-induced overeating; and (4) the Morisky Medication Adherence Scale. The difference between two continuous independent variables was determined using Student’s t test. Discrete variables were compared using the Chi-square (χ(2)) or Fisher’s exact test. Multiple testing corrections were performed using the false discovery rate. RESULTS: Those outpatients in the poor glycemic control group exhibited significantly more stress-induced overeating (χ(2) = 1.14, q statistic = 0.040) and poor medication adherence (t = 3.70, q = 0.034) than those in the better glycemic control group. However, there were no significant differences between the two groups in terms of affective temperaments, clinical eating disorders, or diabetes-specific distress. Patients with stress-induced overeating (t = − 2.99, p = 0.004) and poor medication adherence (t = − 4.34, p = 0.000) exhibited significantly higher scores for cyclothymic temperament than their counterparts. CONCLUSION: Cyclothymic temperament is significantly associated with disordered eating and/or poor medication adherence in patients with type 2 diabetes and is possibly linked to poor glycemic control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13300-021-01121-y.