Clinical Features Of Parkinson’s Disease With Rapid Eye Movement Behavior Disorder And The Association Between Subjective And Objective Sleepiness In Parkinson’s Disease

Background Parkinson’s disease(PD)is a common neurodegenerative disease.In addition to typical motor symptoms including bradykinesia,rest tremor and rigidity,the patients with PD patients are often accompanied by a series of non-motor symptoms such as hyposmia,depression,constipation,recognition and sleep disorders,etc.Rapid eye movement sleep behavior disorder(RBD)is a common sleep disorder in patients with PD.The patients of PD with RBD often have severer clinical symptoms,longer duration,and more dopaminergic drugs,and more non-motor symptoms than those without RBD.If we can further clarify the relationship between PD and RBD,identify the high-risk groups,we can take appropriate measures to prevent it to progress to neurodegenerative diseases.In addition,in many current studies,because of the lack of PSG monitoring equipment,only RBD screening scales are used to diagnose RBD which may overestimate the prevalence of RBD,and may also miss some subclinical RBD or Other sleep related diseases are misdiagnosed as RBD.This study intends to perform PSG examinations to eliminate the possibility of abnormal limb movement during sleep,such as sleep apnea,periodic limb movements,etc.,in combination with the patient’s medical history to clarify the diagnosis of RBD.By comparing the clinical features and PSG parametersbetween PD patients with and without RBD,we intend to comfirme whether PD patients with RBD have more serious symptoms,have more non-motor symptoms and more worse quality of sleep.So we can provide more clinical evidence for the study of RBD and PD.The prevalence of excessive daytime sleepiness(EDS)in patients with PD is approximately 50%.Patients with EDS have inappropriate or unwilling drowsiness,which impair the patient’s daytime function and quality of life.Unexpected drowsiness may also result in falling down,fractures,and other adverse consequences.So identifying EDS early and accurately will contribute to effective intervention and protection measures for these patients.Epworth sleepiness scale(ESS)and Multiple sleep latency test(MSLT)are tools for evaluating EDS from subjective and objective perspective,respectively.At present,there is less study of consistency in the evaluation of EDS for patients with PD,and conclusion is controversial.It may related to study design,methods of statistical analysis,and sample size.Based on this,studying the consistency of ESS and MSLT in evaluating EDS of patients with PD is needed.Method From October 2016 to December 2017,a total of subsequent 62 patients who were diagnosed with PD in our department of neurology and agreed to accept PSG were included.We collected the demographic data and evaluated the Unified Parkinson’s disease rating scale-Part 3(UPDRS-3)and the Hoehn-Yahr scale of all patients,.We also assessed the degree of drowsiness with ESS,subjective sleep quality with the Pittsburgh sleep quality scale(PSQI),restless legs symptoms with the International restless legs syndrome study group rating scale(IRLSS),anxiety with Hamilton rating scale(HAMA),depression with Hamilton rating scale(HAMD),cognitive function with Mini-mental state examination(MMSE),and we also use Montreal Cognitive Assessment Scale(Mo CA)to value the cognitive function of PD.All 62 patients underwent overnight polysomnography examination(PSG),and were divided into PD+RBD and PD-RBD groups according to the patients with and without RBD.The clinical characteristics and PSG parameters were analyzed between the two groups of patients.48 patients received MSLT were divided into four groups according to ESS The quartiles of the score: A(0-3points)(n=12),B(4-9points)(n=13),C(10-12points)(n=13),D(13-24 points)(n=10).Survival analysis was used to analyze the correlation and consistence between ESS and MSLT.The receiver operating characteristic curve(ROC curve)was used to determine the best cut-off value for ESS diagnosis of EDS.P <0.05 was considered statistically significant.Result 1.A total of 62 PD patients were included,including 25 males and 37 females,average age is 62.98±9.17 years and the median duration is 3 years ranging from 1 to 15 years.2.The prevalence of RBD in PD patients was 45.2%(28/62),with no gender difference(P=0.572).3.PD+RBD group had longer disease duration(years)than PD-RBD group(4[1,15] vs 3[1,10],P=0.009),and UPDRS-3 score was higher than PD-RBD group(20.00±5.72 vs 17.38±7.08,P=0.048),the levodopa equivalent dose(mg)was higher than PD-RBD group(442.88±136.67 vs 299.18±215.07,P=0.002).There was no significant difference in H-Y grade between the two groups(2.5 [2.0,5.0] ] vs 2.5 [1.5,4.0],P=0.506);There was no significant difference in ESS scores(8.82±5.89 vs 5.24±3.82,P=0.789);PD+RBD group had significantly lower MMSE and Mo CA scores than PD-RBD Group(22.50±4.99 vs 25.35±3.60,P=0.011;19.21±4.90 vs 23.18±3.30,P<0.001).There was no significant difference in total sleep time,sleep efficiency,sleep latency,proportion of sleep stages,arousal index,and periodic limb movement index between PD+RBD and PD-RBD groups.4.In the 48 patients received PSG and MSLT,19(39.6%)were males and 29(60.4%)were females;mean age was 62.58±9.11 years,mean ESS score was 8.60±5.45 points,and the mean sleep latency was 13.00±4.77 min.There were 22 patients(47.9%)with subjective EDS and 8 patients(12.5%)with objective EDS.5.There was a statistically significant difference in the survival curves between the four groups A,B,C,and D(c2 =14.086,P=0.003).With the time,the patient was more likely to fall asleep.The higher of the ESS score,the patients were more likely to fall asleep.In the Cox proportional hazards model,with group A as a reference,the risk of falling asleep in groups B,C,and D was 2.3,2.0 and 5.7 times higher than group A,respectively.When sex,age,SE and WASO were controlled,the risk of falling asleep in the three groups was 2.6,2.5 and 6.7 times that group A,respectively.6.The patients were divided into two groups with MSL <8 minutes.The ROC curve showed that the best cut-off point for ESS was 14.5 points and the area under the curve was 0.645(95%CI:0.403-0.886).Conclusion 1.The prevalence of RBD in patients with was significantly higher than general population,and there was no difference in gender distribution.2.Patients with PD with RBD have a longer duration,more severe disease,and a higher dose of dopaminergic drugs,but there is no significant difference of sleep architecture between the two groups.3.ESS and MSL is consisitent in evaluting the sleepiness in PD patients.4.The PD patients were divided into two groups with MSL <8 minutes.The ROC curve showed that the best cut-off point for ESS was 14.5 points.Using ESS with a score of 10 points or less as a cutoff value to distinguish EDS may overestimate the incidence of EDS in patients with Parkinson’s disease.