Prevalence of depression and associated risk factors among persons with type-2 diabetes mellitus without a prior psychiatric history: a cross-sectional study in clinical settings in urban Nepal

Background: Diabetes is a growing health problem in South Asia. Despite an increasing number of studies exploring causal pathways between diabetes and depression in high-income countries (HIC), the pathway between the two disorders has received limited attention in low and middle-income countries (LMIC). The aim of this study is to investigate the potential pathway of diabetes contributing to depression, to assess the prevalence of depression, and to evaluate the association of depression severity with diabetes severity. This study uses a clinical sample of persons living with diabetes sequelae without a prior psychiatric history in urban Nepal.

Methods: A cross-sectional study was conducted among 385 persons living with type-2 diabetes attending tertiary centers in Kathmandu, Nepal. Patients with at least three months of diagnosed diabetes and no prior depression diagnosis or family history of depression were recruited randomly using serial selection from outpatient medicine and endocrine departments. Blood pressure, anthropometrics (height, weight, waist and hip circumference) and glycated hemoglobin (HbA_1c) were measured at the time of interview. Depression was measured using the validated Nepali version of the Beck Depression Inventory (BDI-Ia).

Results: The proportion of respondents with depression was 40.3%. Using multivariable analyses, a 1-unit (%) increase in HbA_1c was associated with a 2-point increase in BDI score. Erectile dysfunction was associated with a 5-point increase in BDI-Ia. A 10mmHg increase in blood pressure (both systolic and diastolic) was associated with a 1.4-point increase in BDI-Ia. Other associated variables included waist-hip-ratio (9-point BDI-Ia increase), at least one diabetic complication (1-point BDI-Ia increase), treatment non-adherence (1-point BDI-Ia increase), insulin use (2-point BDI-Ia increase), living in a nuclear family (2-point BDI-Ia increase), and lack of family history of diabetes (1-point BDI-Ia increase). Higher monthly income was associated with increased depression severity (3-point BDI-Ia increase per 100,000 rupees, equivalent US$1000).

Conclusions: Depression is associated with indicators of more severe diabetes disease status in Nepal. The association of depression with diabetes severity and sequelae provide initial support for a causal pathway from diabetes to depression. Integration of mental health services in primary care will be important to combat development of depression among persons living with diabetes.