Background: Depression is one of the most common psychological states in type 2 diabetes that contributes to adverse health outcomes. This study aimed to investigate the risk factors for the incidence of depression in type 2 diabetic patients.

Materials and Methods: In this descriptive cross-sectional study, 254 type 2 diabetic patients were selected through convenience sampling among diabetes outpatient clinics of Tehran university of medical sciences and also Iranian diabetes society during 2010-11. Data were collected using demographic and disease characteristic questionnaire, patient health questionnaire, social support scale and diabetes self-management scale (DSMS) and then analyzed using Chi square, t-test and binary logistic regression.

Results: Increased pain and functional disability (OR=11.725), decreased social support (OR=3.086), decreased performance for diabetes self-care (OR=4.088), longer duration of diabetes (OR=1.328), diabetes complications (OR=2.324), the need for insulin therapy (OR=2.431), HbA1c>9% (OR=21.575), BMI>25kg/m2 (OR=2.251) and major life events (OR=14.043) were significantly different between the diabetic patients with and without depression (P=0.001). There was no significant difference in age, sex and socio-economic status between the two groups. The regression model correctly was fitted in 95.3% of the cases.

Conclusion: Pain and functional disability, poor social support, weaker diabetes self-care, longer duration of diabetes, diabetes complications, the need for insulin therapy, HbA1c>9%, BMI>25kg/m2 and the experience of major life events all together contribute to the incidence of depression in type 2 diabetic patients. The results of the study have implications for the prevention of depression in diabetic patients.