Major depressive disorder and type 2 diabetes commonly co-occur and disease control tends to be poorer when both conditions are present. However, little research has examined the disease characteristics of patients with diabetes and more severe depressive symptoms.
We report a retrospective observational study of 517 patients with diabetes from 2 primary care centers. Patients with diabetes and moderately-severe/severe depression symptoms (Patient Health Questionnaire [PHQ-9] score >15) were compared with patients with diabetes without moderate or severe depression symptoms (PHQ-9 score <15; the comparison group) with regard to control of diabetes, blood pressure, and lipid parameters. Frequency of HbA1c and PHQ-9 testing were also examined.
Patients with diabetes and moderately severe/severe depressive symptoms had higher HbA1c (7.56% vs 7.09%), diastolic blood pressure (78.43 vs 75.67 mm Hg), and low-density lipoprotein cholesterol (109.12 vs 94.22 mg/dL) versus the comparison group. Patients with diabetes and moderately-severe/severe depression underwent HbA1c and PHQ-9 testing with similar frequency to the comparison group.
The presence of moderately severe/severe depressive symptoms was associated with poorer glucose, lipid, and blood pressure control among patients with diabetes. Further research should prospectively examine whether a targeted depression treatment goal (PHQ-9 score <15) in patients with diabetes results in improved control of these important disease parameters.