Mortality and Its Risk Factors in Patients with Rapid Eye Movement Sleep Behavior Disorder.
To determine the mortality and its risk factors in patients with rapid eye movement (REM) sleep behavior disorder (RBD).



A total of 205 consecutive patients with video-polysomnography confirmed RBD (mean age = 66.4 ± 10.0 y, 78.5% males) were recruited. Medical records and death status were systematically reviewed in the computerized records of the health care system. Standardized mortality ratio (SMR) was used to calculate the risk ratio of mortality in RBD with reference to the general population.



Forty-three patients (21.0%) died over a mean follow-up period of 7.1 ± 4.5 y. The SMR was not increased in the overall sample, SMR (95% confidence interval [CI]) = 1.00 (0.73-1.33). However, SMR (95% CI) increased to 1.80 (1.21-2.58) and 1.75 (1.11-2.63) for RBD patients in whom neurodegenerative diseases and dementia, respectively, eventually developed. In the Cox regression model, mortality risk was significantly associated with age (hazard ratio [HR] = 1.05; 95% CI, 1.01-1.10), living alone (HR = 2.04; 95% CI, 1.39-2.99), chronic obstructive pulmonary disease (HR = 3.38; 95% CI, 1.21-9.46), cancer (HR = 10.09; 95% CI, 2.65-38.42), periodic limb movements during sleep (HR = 3.06; 95% CI, 1.50-6.24), and development of neurodegenerative diseases (HR = 2.84; 95% CI, 1.47-5.45) and dementia (HR = 2.66; 95% CI, 1.39-5.08).



Patients with RBD have a higher mortality rate than the general population only if neurodegenerative diseases develop. Several risk factors on clinical and sleep aspects are associated with mortality in RBD patients. Our findings underscore the necessity of timely neuroprotective interventions in the early phase of RBD before the development of neurodegenerative diseases.
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.|Sleep Medicine Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Junying
J
Zhou
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Jihui
J
Zhang
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Siu Ping
SP
Lam
Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Vincent
V
Mok
Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Anne
A
Chan
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.|Department of Psychology, The University of Hong Kong, Pokfulam, Hong Kong SAR.
Shirley Xin
SX
Li
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Yaping
Y
Liu
Sleep Medicine Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Xiangdong
X
Tang
School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Wing Ho
WH
Yung
Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong SAR.
Yun Kwok
YK
Wing
D000367:Age Factors; D000368:Aged; D003704:Dementia / Q000150:complications / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications; D019636:Neurodegenerative Diseases / Q000150:complications* / Q000503:physiopathology / Q000517:prevention & control; D020189:Nocturnal Myoclonus Syndrome / Q000150:complications; D017286:Polysomnography; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications; D020187:REM Sleep Behavior Disorder / Q000150:complications / Q000401:mortality* / Q000503:physiopathology*; D012307:Risk Factors; D012890:Sleep
REM sleep behavior disorder; SMR; mortality; neurodegenerative disease