A longitudinal study of restless legs symptoms among patients with depression

The aim of this study was to analyse the relationship between depressive symptoms and clinical depression and restless legs symptoms in a longitudinal primary care setting.

The prevalence of restless legs symptoms at baseline and after a six-year follow-up was studied in 474 patients with depressive symptoms and 333 population-based control subjects without depressive symptoms. Depressive symptoms at the baseline and after the six-year follow-up were evaluated with the Beck Depression Inventory (BDI) Second Edition. A psychiatric diagnosis was confirmed with a diagnostic interview (M.I.N.I.). Statistical comparisons between groups were made using analysis of variance (ANOVA) for continuous variables and a chi-square test or logistic models for categorical variables. Repeated measures were analysed using generalizing estimating equations (GEE) models.

At baseline the prevalence of restless legs symptoms was 24.3% in control subjects, 43.8% in the patients with depressive symptoms without a depression diagnosis, and 49.3% in clinically depressed patients. During the follow-up up the prevalence of restless legs symptoms declined significantly (p = 0.003). In addition to baseline restless legs symptoms, the prognostic factors for restless legs symptoms among patients with clinical depression were age and BDI score. In the control subjects, moderate and high leisure time physical activity was inversely associated with restless legs symptoms at the follow-up.

A higher level of baseline depressive symptoms was a risk factor for restless legs symptoms in patients with clinical depression. In the prevention and treatment of restless legs symptoms among the patients with depression, the priority is the effective treatment of depression.