Objective
To assess in participants in the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study (DPP/DPPOS) whether diagnosis of diabetes predicted: elevated depressive symptoms (DS) or antidepressant medicine (ADM) use after diagnosis; diabetes status or duration had significant effect on DS or ADM use; and associations between A1C, fasting plasma glucose (FPG), normalization of FPG and DS or ADM use post diagnosis.
Methods
DPP participants in 3 treatment arms [intensive lifestyle (ILS), metformin (MET), placebo (PLC)] were assessed semiannually or annually for diabetes, glucose control, ADM use, and DS. DS was measured using Beck Depression Inventory (BDI) questionnaire. Among the total 3234 enrolled participants, 1285 developed diabetes whose levels of depression were measured before and after their diabetes diagnosis.
Results
Neither DS nor ADM use increased significantly following diabetes diagnosis. After diabetes diagnosis, higher FPG was associated with greater ADM use in the ILS arm independent of potential confounders; a 10 mg/dl higher in FPG is associated with 8.8% more odds of ADM use. Higher FPG, and higher A1C were associated with higher BDI scores in all three arms. On average, a participant with 10 mg/dl higher rise in FPG had a 0.07 increase in BDI score. Similarly, 1% higher A1c was associated with a 0.21 point increase in BDI score. On contrary, normalization of FPG was associated with lower BDI scores. In participants with FPG that had normalized, there was a decrease of 0.30 points in the BDI score compared to those whose FPG had not normalized.
Conclusions
Contrary to clinical attributions, the diagnosis of diabetes did not show an immediate impact on BDI scores or ADM use. However, higher glucose levels after diagnosis were associated with small but significant higher BDI score and more ADM use.