. 2007 Aug 1;30(8):1019–1025. doi: 10.1093/sleep/30.8.1019

Table 2.

NREM-to-REM Sleep Changes in R-R Variability and Respiration in Patients with RBD and Controls

	Patients with RBD		Control subjects		P Value
	NREM	REM	NREM	REM	P Value
R-R interval, ms	1000 ± 48	1011 ±53	984 ± 27	962 ± 28	State: P = NS
					Group: P = NS
					Interaction: P = 0.058
pNN50, %	2.2 ± 0.9	1.8 ±1.0	3.4 ±1.2	1.1 ±0.5	State: P < 0.05
					Group: P = NS
					Interaction: P = NS
Total power, ms²	788 ± 197	1108 ± 401	970 ± 221	1274 ± 209	State: P = NS
					Group: P = NS
					Interaction: P = NS
LF, ms²	449 ± 170	411 ±237	483 ± 114	348 ± 87	State: P = NS
					Group: P = NS
					Interaction: P = NS
LF, nu	59.8 ± 5.7	58.6 ±7.0	61.0 ±4.4	73 ± 2.9	State: P = NS
					Group: P = NS
					Interaction: P < 0.05^*
HF, ms²	134 ±30	96 ±34	190 ± 36	53 ±13	State: P < 0.001
					Group: P = NS
					Interaction: P < 0.05^**
HF, nu	31.1 ± 5.3	30.2 ± 4.8	30.4 ± 4.1	14.5 ±1.8	State: P< 0.01
					Group: P = NS
					Interaction: P < 0.01^***
LF/HF	5.0 ± 2.0	5.1 ±1.7	4.8 ± 1.4	9.2 ± 1.8	State: P < 0.001
					Group: P = NS
					Interaction: P< 0.001^***

Planned comparison: *P < 0.05;

**P < 0.001;

***P < 0.0001 in controls derived from 2 × 2 analysis of variance

Data are presented as mean ± SD. NREM refers to non-rapid eye movement sleep; RBD, REM (rapid eye movement) sleep behavior disorder; pNN50, the percentage of 50-ms or greater differences between adjacent R-R intervals; LF, low frequency; HF, high frequency; nu, normalized units.