Major depressive disorder in patients with diabetes mellitus in Pietermaritzburg, South Africa

BACKGROUND. Diabetes mellitus (DM) and major depressive disorder (MDD) constitute a major burden of disease. A study found that type 2 DM (DM2) is associated with a two-fold increase in risk of developing MDD worldwide - except in Africa. The present study challenges this statement. OBJECTIVES. To determine the prevalence of MDD in a cohort of patients with DM and its effect on glycaemic control. METHODS. A cross-sectional study was performed at a diabetes clinic at Edendale Hospital, Pietermaritzburg, South Africa (1 March -31 May 2017). A total of 176 participants were enrolled. Participants completed the Patient Health Questionnaire-9 (PHQ-9), with a score of > 10 representing a diagnosis of MDD. Higher PHQ-9 scores translate into more severe MDD. A surrogate for glycaemic control, glycated haemoglobin (HbAlc) blood testing, was also performed. RESULTS. The majority of participants were female and suffered from DM2. The mean age was 54.4 years. The prevalence of MDD in the study population was 46.6%. A significantly positive linear relationship was shown between PHQ-9 score and HbAlc (p=0.018253). CONCLUSIONS. MDD appears to constitute a large burden of disease in our population of individuals with DM. A relationship between the severity of the MDD and HbAlc suggests that prompt intervention in both conditions is likely to improve health outcomes.