Introduction. Restless legs syndrome has been shown to negatively impact the quality of life of patients. Studies have shown an association between restless legs syndrome and Parkinson’s disease. We attempted to investigate the prevalence of restless legs syndrome in Parkinson’s disease patients and to identify associated risk factors. Method. This was a cross-sectional study among patients with idiopathic Parkinson’s disease. Exclusion criterion was a Mini Mental State Examination score of less than 21/30. The International Restless Legs Syndrome Study Group criterion was used to identify patients with restless legs syndrome. Results. A total of 113 patients were recruited. The prevalence rate of restless legs syndrome in our cohort was 9.7% and was significantly associated with a younger onset of Parkinson’s disease ( ), male gender ( ), higher Mini Mental State Examination score ( ), and less advanced Hoehn & Yahr stage ( ). Conclusion. The prevalence rate of restless legs syndrome in our Parkinson’s disease population is in keeping with other studies published worldwide. The significance of the association between a younger onset of Parkinson’s disease and restless legs syndrome needs to be further investigated. 1. Introduction Restless legs syndrome (RLS) is one of the most common movement disorders in the general population [1–4]. The condition has traditionally been classified as primary or secondary to other medical conditions such as low iron stores, renal failure, pregnancy, and rheumatological conditions [5–8]. Recent studies have revealed a significant genetic interplay in the development of RLS [9]. It has been shown to be one of the causes of intrinsic insomnia [10]. Left undiagnosed and untreated, RLS negatively impacts the quality of life of sufferers [11, 12]. There have been studies showing an association between RLS and Parkinson’s disease (PD) [13–15]. Both of these conditions have been shown to respond to dopaminergic treatment [16]. There have been suggestions that the prevalence rate of RLS in PD patients between the Caucasian and Asian population is different, attributable to cultural and genetic differences [17]. We aim to study the prevalence of RLS in PD patients in Malaysia. We also attempted to investigate any possible risk factors that could be associated with RLS in PD patients. 2. Methodology This was a cross-sectional observational study conducted at Universiti Kebangsaan Malaysia Medical Centre from December 2009 till August 2010. Consecutive PD patients aged 18 and older, attending the neurology clinic, were invited to
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