Convergence of psychiatric symptoms and restless legs syndrome: A cross-sectional study in an elderly French population

Abstract Objective The objective was to evaluate the association between restless legs syndrome (RLS) with generalized anxiety disorder (GAD), major depression disorder (MDD), dysthymia, and GAD-depression comorbidity. Secondary aims were to examine the association between RLS with the cognitive-affective and somatic-vegetative disturbances experienced as part of depression and GAD. Methods This was a cross-sectional study of 1493 elderly participants (median age 80.6 years, 64% women) from Dijon, France. Probable RLS was assessed using the minimal diagnostic criteria of the International Restless Legs Study Group and RLS symptom frequency and treatment. Participants underwent structured interviews for MDD, dysthymia, and GAD. Participants also completed the Center for Epidemiological Studies-Depression scale (CES-D). The association between RLS and psychiatric disorders, their criterion symptoms, or symptom factors was examined using logistic regression. Results The point prevalence of probable RLS in this sample was 8.2%. Probable RLS was associated with isolated GAD (odds ratio [OR] 2.17, 95% confidence interval [CI] 1.01–4.68) and comorbid GAD-any depression disorder (OR 3.26, 95% CI 1.14–9.29), but not MDD or dysthymia. Probable RLS was also associated with the GAD criterion worry most days and feeling tense, and the CES-D factors representing depressed affect, somatic symptoms, and positive affect. Conclusions Probable RLS was associated with GAD-depression comorbidity as well as isolated GAD. The findings challenge previous reports linking RLS solely with MDD, suggesting the association is partly driven by GAD-depression comorbidity.