The affective and somatic side of depression: subtypes of depressive symptoms show diametrically opposed associations with glycemic control in people with type 1 diabetes.

AIMS: While depression has been linked to serious adverse outcomes in diabetes, associations with glycemic control are not conclusive. Inconsistencies could be due to the complex symptomatology of depression. Aim of this study was to analyze the associations of depressive subtypes with glycemic control in people with type 1 and type 2 diabetes.

METHODS: Patients completed the Center for Epidemiological Studies-Depression scale which comprises affective, somatic, and anhedonic symptoms. These subtypes were analyzed in a joint linear regression analysis with glycemic control as a dependent variable. Subtype scores were calculated as mean item scores. Separate analyses for people with type 1 and type 2 diabetes were conducted. All analyses were controlled for demographic and medical confounders.

RESULTS: The sample comprised 604 patients with type 1 and 382 patients with type 2 diabetes. In people with type 1 diabetes, the somatic and affective subtype showed diametrically opposed associations with glycemic control (somatic: β =+0.23, p < .05; affective: β = -0.23, p < .05). Anhedonia was not significantly associated with glycemic control. In people with type 2 diabetes, none of the depressive subtypes was significantly associated with glycemic control.

CONCLUSIONS: For people with type 1 diabetes, the distinction of subtypes offered a detailed picture of the associations of depressive symptoms with glycemic control. However, due to the cross-sectional design, inferences about the direction of these associations cannot be made. In clinical practice, instead of focusing on overall depression, healthcare providers should examine the nature of depressive symptoms and how they might be related to having diabetes.