Table 2.

Time and Frequency Domain Measures of HRV

		Stable	SDB	Time P	Breathing P
TIME DOMAIN
mean HR (bpm)	First	69.3±11.9	66.6±11.3	ns	ns
	Last	65.1±11.4	66.1±11.7
meanNN (ms)	First	888±141	923±142	ns	ns
	Last	948±164	932±150
medianNN (ms)	First	887±141	927±145	ns	ns
	Last	948±164	934±154
maxNN (ms)	First	958±155	1044±168	ns	<0.001
	Last	1022±184	1049±158
minNN (ms)	First	824±135	780±112	ns	<0.001
	Last	875±144	789±123
rangeNN (ms)	First	134±66	264±119	ns	<0.001
	Last	147±86	288±118
SDNN (ms)	First	21.2±10.6	44.8±21.4	ns	<0.001
	Last	23.8±13.3	47.2±22.3
SDdNN (ms)	First	20.0±12.1	23.8±16.0	ns	0.019
	Last	19.2±13.0	23.1±14.1
NN50 (count)	First	31.6±63.6	42.3±67.7	ns	ns
	Last	25.8±49.3	36.3±63.9
FREQUENCY DOMAIN
TP ln (ms2)	First	2.50±0.46	3.21±0.44	ns	<0.001
	Last	2.58±0.52	3.25±0.42
VLF ln (ms2)	First	1.78±0.48	2.92±0.46	ns	<0.001
	Last	1.99±0.59	3.01±0.47
LF ln (ms2)	First	1.75±0.57	2.36±0.54	ns	<0.001
	Last	1.87±0.65	2.25±0.57
HF ln (ms2)	First	1.90±0.58	2.06±0.60	ns	ns
	Last	1.89±0.65	1.94±0.60
LF/HF	First	0.97±0.65	2.47±1.47	ns	<0.001
	Last	1.36±1.23	2.91±2.59

Obtained from the first and last stable breathing and SDB conditions. Influence of 2 factors, i.e., time and breathing were assessed using 2-way Repeated Measures ANOVA, hence 2 P-values are given.