Restless legs syndrome in the elderly; Prevalence, impact on quality of sleep and association with major depressive disorder

초록

Background: In older population, prevalence of RLS seems to increase although it is not proven yet. A few studies have examined the potential association between RLS and major depressive disorder in older population. Objective: We examined the prevalence of RLS, association between RLS and demographic variables, impact of RLS on quality of sleep, and the association between RLS and MDD in elderly population. Methods: Face-to-face household survey was conducted in four different regions of Korea from June 2008 to August 2008. There were 2,524 subjects, aged more than 65, and the response rate was 69.0% (Number of responder was 1,738). The diagnosis of RLS was made by using the RLS questionnaire (the Korean version of Paradigm of questions for epidemiology studies of RLS). Past medical histories were grouped as nine disease categories which physician diagnosed. Nine disease categories were as follows; hypertension, diabetes melitus, hyperlipidemia, stroke, heart disease (angina, arrhythmia, heart failure, myocardial infarction), atherosclerosis, peripheral vessel disease, abdominal aortic aneurysm, anemia, and renal disease. The quality of sleep was measured by five items of insomnia severity index. Major depressive disorder was diagnosed by the diagnostic section of depressive disorder in Korean version of composite international diagnostic interview(K-CIDI). Results: The prevalence of RLS in older population was 10.7% (men 8.9%; women 11.9%) and it seemed to increase with age, reaching a peak prevalence of 18.5% in the eldelry aged more than 90 years. 21.5% of subjects with RLS and 31.0% of subjects without RLS had past medical history. Anemia and renal diseases had significant association with RLS (p<0.05). The subjects with RLS reported to have worse quality of sleep in five items of insomnia severity index than general population (P<0.001). 31.2% of subjects with RLS and 17.5% of subjects without RLS had major depressive disorder. Odd ratios with confid