Predictive markers for early conversion of iRBD to neurodegenerative synucleinopathy diseases.
OBJECTIVE
To determine the predictive value of clinical assessment and dopamine transporter (DAT) uptake for the early development of neurodegenerative synucleinopathy diseases from idiopathic REM sleep behavior disorder (iRBD) over 5 years in a Chinese population.


METHODS
Forty-three patients with iRBD were administered clinical assessment tests, and 35 were examined by DAT-SPECT imaging during 2011. Cox proportional hazard and Kaplan-Meier analyses were used to evaluate the predictive value of the markers in a follow-up study over 5 years.


RESULTS
Eighteen patients (41.9%) developed neurodegenerative synucleinopathy diseases after a median of 4.1 years of prospective follow-up (median interval of 10.5 years from the estimated onset of iRBD symptoms). Patients with higher scores on the Nonmotor Symptom Questionnaire (hazard ratio [HR] 3.11, 95% confidence interval [CI] 1.15-8.40,p= 0.026) and Scale for Outcomes in Parkinson Disease-Autonomic questionnaire (HR 4.46, 95% CI 1.64-12.10,p= 0.003) were more likely to develop neurodegenerative synucleinopathy diseases. Furthermore, the population with decreased99mTc-TRODAT-1 binding in the left striatum (HR 2.7, 95% CI 1.02-7.14,p= 0.046) and putamen (HR 3.23, 95% CI 1.16-8.33,p= 0.024) had a relatively higher risk of developing neurodegenerative synucleinopathy diseases.


CONCLUSIONS
Our findings elucidate the predictive value of autonomic dysfunction and DAT uptake in identifying patients with iRBD at a high risk of progressing into neurodegenerative synucleinopathy diseases and could form a basis for future disease-prevention trials.
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Yuanyuan
Y
Li
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Wenyan
W
Kang
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Qiong
Q
Yang
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Lina
L
Zhang
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Linyuan
L
Zhang
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China.
Fangyi
F
Dong
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China. jly0520@hotmail.com chen_sd@medmail.com.cn.
Shengdi
S
Chen
From the Department of Neurology and Institute of Neurology (Y.L., W.K., Q.Y., Linyuan Zhang, F.D., S.C., J.L.), Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine; Department of Neurology (W.K.), Ruijin Hospital North affiliated to Shanghai Jiaotong University School of Medicine; and Department of Biostatistics (Lina Zhang), Shanghai Jiaotong University School of Medicine, Shanghai, China. jly0520@hotmail.com chen_sd@medmail.com.cn.
Jun
J
Liu
D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D002681:China; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D019636:Neurodegenerative Diseases / Q000000981:diagnostic imaging*; D015609:Organotechnetium Compounds; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D020187:REM Sleep Behavior Disorder / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals; D011795:Surveys and Questionnaires; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1