Measures of depression and incident type 2 diabetes in a community sample

The purpose of this study was to estimate associations between distinct measures of depression and incident type 2 diabetes.

Our sample consisted of 30,360 community-dwelling adults aged 40 to 69 in Canada. Depression was defined as elevated depressive symptoms using the Patient Health Questionnaire 9, diagnoses of depression in administrative data, or antidepressant use from a medication inventory. Type 2 diabetes was ascertained in administrative data over up to 7 years of follow-up. Cox proportional hazards models were used to estimate associations between different measures of depression and incident diabetes.

In separate models, elevated depressive symptoms were associated with a 17% increased risk of type 2 diabetes (hazard ratio (HR) 1.17, 95% confidence interval (CI) 1.02-1.34), diagnoses of depression were associated with a 20% increased risk (HR 1.20, 95% CI 0.94-1.52), and antidepressant use was associated with a 19% increased risk (HR 1.19, 95% CI 1.01-1.41). When examining combinations of measures in the same model, depressive symptoms paired with antidepressant use and depressive symptoms paired with diagnoses of depression were associated with the highest risk of type 2 diabetes.

Various measures of depression and combinations of measures can be used to identify older adults at higher risk of type 2 diabetes in research and public health.