Depression, depression treatment, and insulin sensitivity in adults at risk for type 2 diabetes

To compare insulin sensitivity (Si) in adults at risk for type 2 diabetes (T2DM) who were categorized as non-depressed, treated for depression and untreated depression after controlling for physical activity (PA).

Baseline data was analyzed from individuals enrolled in a diabetes prevention program (n=56). Si was calculated using the whole-body insulin sensitivity method. The Centers for Epidemiologic Studies Depression Scale (CESD) was used to assess depressive symptoms and depressed cases were identified using a cutoff of >or=16. Depression treatment was identified using a self-report form validated by medical chart review. The PA subscale of the Health Promoting Lifestyle Profile was used to determine PA levels.

One third of participants had elevated depressive symptoms; 19% were taking antidepressant medication. Mean Si was 3.1 (+/-1.9). In ANOVA, depressed individuals showed significantly lower Si (M=1.8+/-0.9) than non-depressed individuals (M=3.4+/-1.8). However, individuals taking antidepressant medications had Si similar to non-depressed individuals (M=3.7+/-2.3: p=.63). In ANCOVA this association remained after controlling for PA.

These data suggest that in adults at high risk for T2DM, depression treatment may improve insulin resistance observed in depression. Healthcare practitioners are encouraged to screen, treat, or refer their patients with depression for treatment.