Glycaemic status and depressive symptoms among adults in Germany: results from the German Health Interview and Examination Survey for Adults (DEGS1)

Abstract

Aims: To examine the association between glycaemic status and depressive symptoms in a nationwide sample of the adult population in Germany.

Methods: We conducted a cross-sectional analysis of data from 6385 participants aged 18-79 years in the nationwide German Health Interview and Examination Survey for Adults 2008-2011 (DEGS1). Glycaemic status was classified as follows: diagnosed diabetes (self-reported diagnosis or receiving antidiabetes medication); undiagnosed diabetes (HbA_1c ≥48 mmol/mol [≥6.5%]); prediabetes (HbA_1c 39-47 mmol/mol [5.7-6.4%]); or normoglycaemia (HbA_1c <39 mmol/mol [<5.7%]). Current depressive symptoms were measured using the Patient Health Questionnaire depression scale (PHQ-9) and defined as elevated depressive symptoms (PHQ-9 score ≥10 points; dichotomous variable) and severity of depressive symptoms (PHQ-9 score, range 0-27 points; continuous variable). Associations of glycaemic status and HbA_1c with both depressive symptoms variables were analysed using multivariable logistic (elevated depressive symptoms) and linear (severity of depressive symptoms) regression models.

Results: Compared with normoglycaemia, diagnosed diabetes, but not prediabetes or undiagnosed diabetes, was associated with elevated depressive symptoms (odds ratio 1.55, 95% CI 1.00-2.41) and severity of depressive symptoms (β coefficient 0.71, 95% CI 0.23-1.19) in models adjusting for sociodemographics and health behaviours. Associations were similar among people with diagnosed diabetes taking and not taking antidiabetes medication. Among people without diagnosed diabetes, no associations between HbA_1c and depressive symptoms were found.

Conclusions: Diagnosed diabetes, but not prediabetes, undiagnosed diabetes or HbA_1c , was associated with depressive symptoms among adults in Germany. Studies examining psychosocial and biological mechanisms that may potentially explain relationships between diagnosed diabetes and depressive symptoms are needed.