Table 1.

Baseline demographic, clinical, and polysomnographic characteristics

Characteristics	PDD	PDnD	Controls	P- value
	n = 18	n = 50	n = 44
	A	B	C
Gender, % male	72	66	68	0.83
Age, y	70.2 ± 7.6	63.0 ± 8.5	64.8 ± 10.9	0.02; A>B
Education, y	14.4 ± 3.8	14.3 ± 4.1	14.3 ± 3.7	0.99
Follow-up duration, y a	4.6 ± 1.5	3.9 ± 1.8	-	0.15
Disease duration, y a	5.7 ± 4.5	4.1 ± 3.1	-	0.26
Hoehn and Yahr stage	2.8 ± 0.9	2.1 ± 0.8	-	0.007
UPDRS part III ‘on’	21.5 ± 12.5	22.8 ± 10.1	-	0.67
RBD, n (%)	16 (89)	20 (40)	-	0.0001
MCI, n (%)	16 (89)	21 (42)	-	0.001
Levodopa equivalent dosage, mg	645.6 ± 335.3	416.2 ± 319.2	-	0.01
Non-dopaminergic medication, % b	42	50	-	0.56
BDI-II score c	12.7 ± 9.4	9.6 ± 5.8	5.3 ± 5.6	<0.001; A>C, B>C
BAI score c	13.9 ± 11.2	9.5 ± 6.1	5.5 ± 6.2	0.002; A>C
Polysomnographic
Sleep latency, min c	28.6 ± 36.0	16.0 ± 17.4	18.8 ± 22.0	0.46
Total sleep time, min	337.8 ± 133.0	357.3 ± 82.4	384.3 ± 63.1	0.11
Sleep efficiency, %	72.6 ± 20.7	77.2 ± 15.8	81.9 ± 11.4	0.08
REM sleep efficiency, %	84.8 ± 14.5	88.1 ± 12.8	83.2 ± 11.3	0.16
Stage 1, min c	34.9 ± 20.4	44.6 ± 30.4	43.4 ± 21.9	0.34
Stage 2, min	186.6 ± 80.2	222.7 ± 72.4	249.3 ± 54.1	0.004; A<C
Slow wave sleep, min c	45.0 ± 41.4	31.7 ± 34.7	23.6 ± 24.9	0.10
REM sleep, min c	71.3 ± 62.2	58.3 ± 30.0	68.0 ± 21.4	0.16

^a Mann-Whitney U-test.

^b Non-dopaminergic medication included antiparkinsonians, acetylcholinesterase inhibitors, antidepressants, and benzodiazepines.

^c Kruskal-Wallis ANOVA.

Results are expressed as mean ± standard deviation.