Idiopathic REM Sleep Behavior Disorder: Implications for the Pathogenesis of Lewy Body Diseases

Table 1

Clinical characteristics of patients in the iRBD, PD, and control groups.

	iRBD	PD	Controls	𝑃 value
Number of patients, (𝑛)	30	38	20	—
Age, years	65.8±9.1	65.4±9.2	62.3±6.8	0.210^a
Sex (male, %)	83.3	63.2	90.0	0.102^c
Disease duration, years	5.7±8.8	4.8±4.8	N/A	0.599^b
MMSE (>24)	27.7±2.3	27.9±1.9	28.8±1.4	0.096^a
Hoehn and Yahr stage	N/A	2.4±0.8	N/A	N/A
UPDRS motor subset, score	0.6±1.0	14.4±7.8	N/A	0.000^b
LEU, mg/day	N/A	238.6±261.9	N/A	N/A
Smoker, (%)	50.0	39.5	5.0	0.464^c
OSIT-J, score	5.2±3.0	4.4±2.4	10.3±1.3	0.000^a
^123I-MIBG
Early H/M ratio	1.85±0.33	2.14±0.52	2.74±0.33	0.000^a
Delayed H/M ratio	1.46±0.29	1.83±0.60	2.82±0.47	0.000^a

Data are mean ± SD.
PD: Parkinson’s disease, iRBD: idiopathic REM sleep behavior disorder, OSAS: obstructive sleep apnea syndrome, MMSE: Mini-Mental State Examination, UPDRS: Unified Parkinson’s Disease Rating Scale, LEU: daily levodopa-equivalent unit, OSIT-J: Odor Stick Identification Test for Japanese, H/M: heart-to-mediastinum, and ¹²³I-MIBG: ¹²³I-metaiodobenzylguanidine.
^a𝑃 value was determined by one-way ANOVA.
^b𝑃 value was determined by Mann-Whitney U test.
^cChi-square test for categorical: PD versus iRBD.