Affective and anxiety disorders in a German sample of diabetic patients: prevalence, comorbidity and risk factors

Aims The aims of this study were to examine (1) the prevalence of clinical and subclinical anxiety and affective disorders in a sample of diabetic patients attending a secondary care clinic in Germany and (2) risk factors associated with the occurrence of these disorders. Methods Four hundred and twenty diabetic patients (36.9% Type 1; 24.7% Type 2; 38.4% Type 2 with insulin) participated in a questionnaire-based screening survey. Those who screened positive received a diagnostic interview. Results Prevalence of clinical affective disorders was 12.6%, with an additional 18.8% of patients reporting depressive symptoms without fulfilling all criteria for a clinical affective disorder. The prevalence of anxiety disorders was 5.9%, with an additional 19.3% of patients reporting some anxiety symptoms. The comorbidity rate of affective and anxiety disorders was 1.8%, whereas 21.4% of the diabetic patients reported elevated affective as well as anxiety symptomatology. Logistic regression established demographic variables such as age, female gender and living alone as well as diabetes-specific parameters such as insulin treatment in Type 2 diabetes, hypoglycaemia problems and poor glycaemic control as risk factors for affective disorders. For anxiety symptoms female gender, younger age and Type 2 diabetes were significant independent variables. Conclusion The prevalence of affective disorders in diabetic patients was twofold higher than in the non-diabetic population, whereas prevalence for anxiety disorders was not increased. Analysis of risk factors can facilitate the identification of patients who are at a greater risk for these disorders.