Restless Legs Syndrome in Parkinson's Disease Patients: Clinical Features Including Motor and Nonmotor Symptoms

BACKGROUND AND PURPOSE: We investigated the frequency and clinical features of restless legs syndrome (RLS) in patients with Parkinson's disease (PD). METHODS: This study included 74 PD patients. RLS was diagnosed in face-to-face assessments of all of the subjects based on diagnostic criteria of the International Restless Legs Syndrome Study Group revised in 2003. We analyzed the clinical features of PD patients with and without RLS and compared the data to idiopathic RLS. RESULTS: The frequency of RLS in the cohort was 21.6% (n=16). Two (12.5%) of the patients with RLS were not treated with dopaminergic drugs, while 14 (24.1%) of the 58 patients without RLS received treatment with dopaminergic drugs. Anxiety, depression, and quality of life (QoL) were significantly worst in patients with RLS. PD patients with RLS had significantly worse sleep quality (p=0.003) and worse scores on the cardiovascular subscale of the Scales for Outcomes in Parkinson's Disease for Autonomic Symptoms (p=0.031) compared to those without RLS. In the group of PD patients with RLS, RLS preceding PD onset was related to a lower Hoehn and Yahr stage. CONCLUSIONS: We found that the frequency of RLS in the present patients with PD was higher than that in our previous study of a general population of RLS subjects. Compared to the PD patients without RLS, the present PD patients with RLS suffered from worse sleep quality and QoL, depression, anxiety, and autonomic disturbances, especially those with cardiovascular problems.

Clinical Risk Factors for Sleep Apnea in a Korean Sleep Clinic

BACKGROUND: Sleep apnea is a common sleep disorder. Since polysomnography is essential for the diagnosis of sleep apnea, patient screening or selection is an important issue in the sleep clinic. The purpose of this study was to investigate the clinical risk factors of sleep apnea in a representative sleep clinic in South Korea. METHODS: The medical records of the 7,559 adult patients who visited the sleep clinic from 2009 to 2018 were reviewed. We investigated the demographic data and the results of the sleep questionnaires and polysomnography to determine clinical risk factors of sleep apnea for patients at the sleep clinic. Apnea-hypopnea index over 15 was regarded as clinically significant sleep apnea. RESULTS: A total of 4,581 patients were finally analyzed. In order of significance, age (odds ratio [OR]=1.224 from 50 to 64, p=0.027; OR=1.858 in 65 or more, p<0.001), sex (male) (OR=5.900, p<0.001), body mass index (OR=2.833 from 25 to 29.9 kg/m², p<0.001; OR=9.388 over 30 kg/m², p<0.001) and hypertension (OR=1.537, p<0.001) were independent risk factors of sleep apnea. CONCLUSIONS: In South Korea, it is necessary to specify the risk factors of sleep apnea according to the health related characteristics of Koreans. Further research to develop new instruments for screening sleep apnea in Korean sleep clinics is needed.