Self-rated health: a predictor for the three year incidence of major depression in individuals with Type II diabetes.

Background: To determine whether self-rated health was a predictor for the three year incidence of major depression in people with Type II diabetes.

Methods: Data was collected as part a population-based telephone survey of adults with diabetes, in Québec, Canada (2008-2011). Adults with Type II diabetes who did not have major depression at baseline were assessed at three follow-up interviews conducted 12, 24 and 36 months after baseline. Depression was assessed using the Patient Health Questionnaire (PHQ-9). Self-rated health status was determined by asking participants to rate their health on a scale from excellent to poor.

Results: The sample consisted of 1265 adults with Type II diabetes who did not have major depression at baseline. 36% of individuals who had developed major depression at follow up rated their health as fair or poor at baseline compared to 14.4% of those who had not developed major depression. Logistic regression analyses indicated fair or poor self-rated health at baseline to be predictive of a twofold increased risk for major depression at follow-up, even after adjusting for socio-demographic characteristics, lifestyle-related behaviors, disability and diabetes characteristics (OR=2.05, 95% CI 1.20-3.48).

Limitations: We have focused on current depression (last two weeks) and we have used a questionnaire (PHQ-9) rather than a clinical interview for the assessment of depression.

Conclusions: Self-rated health status might be a predictor for developing major depression in people with diabetes in addition to well established risk factors.