Prevalence and risk factors of RLS in an elderly population: the MEMO study. Memory and Morbidity in Augsburg Elderly

Abstract

Objective: To evaluate prevalence, sociodemographic characteristics, and risk factors of restless legs syndrome (RLS) in a population-based survey of the elderly, using standard diagnostic criteria.

Background: Population-based studies of RLS are rare and have not yet used standard definition criteria.

Methods: The Memory and Morbidity in Augsburg Elderly (MEMO) Study is a follow-up project of the World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease (MONICA) Survey-Augsburg, Germany, 1989-1990, evaluating neurologic diseases and their risk factors in a German population 65 to 83 years of age. Two RLS-trained physicians assessed the prevalence of RLS based on the four minimal standard criteria (International Restless Legs Syndrome Study Group, 1995) using standardized questions in face-to-face interviews. They also obtained information on medical history, medications, depression (Center of Epidemiologic Studies Depression Scale), and quality of life (Short Form 36) and performed a standardized neurologic examination for each participant.

Results: The study population included 369 participants (173 women and 196 men). The overall prevalence of RLS was 9.8% (n = 36) and higher in women (13.9% versus 6.1%; p = 0.02). In women, the prevalence did not change with age, whereas men showed a nonsignificant inverse trend with increasing age. RLS-positive individuals took more benzodiazepines and estrogen compared with non-RLS cases, but the differences were not statistically significant. Participants with RLS had higher incidence of depression (p = 0.012) and lower self-reported mental health scores (p = 0.029) than did non-RLS cases.

Conclusions: RLS is a frequent syndrome in the elderly with considerable impact on self-perceived mental health, affecting women about twice as often as men.