. 2017 Jul 10;140(8):2104–2111. doi: 10.1093/brain/awx148

Table 1.

Demographic and sleep characteristics

	Sham condition Mean ± SD	SWA disruption Mean ± SD	P-value
Demographics
Age (years)	54.1 ± 6.7	n/a
Race White n (%)	11 (65)	n/a
Sex female n (%)	11 (65)	n/a
Body mass index (kg/m²)	28.2 ± 4.3	n/a
Education (years)	15.8 ± 1.6	n/a
Alcohol (drinks/week)	1.6 ± 2.1	n/a
MMSE	29.6 ± 0.5	n/a
APOE ɛ4 carrier n (%)	5 (29)	n/a
Polysomnogram
Total sleep time (min)	419 ± 47	404 ± 51	0.160
non-REM sleep (min)	311 ± 39	300 ± 49	0.244
N1 (min)	22 ± 10	34 ± 18	0.007
N2 (min)	265 ± 44	254 ± 43	0.33
N3 (min)	7 ± 42^a	0 ± 2^a	<0.001^a
REM (min)	99 ± 52^a	68 ± 38^a	0.001^a
Sleep efficiency (%)	85.4 ± 8.5	82.4 ± 9.6	0.102
Number tones delivered	0	1177 ± 427	n/a
EEG spectral power
0.5–4 Hz (Delta) (μV²×s)	118 ± 51	96 ± 43	<0.001
4–8 Hz (μV²×s)	12.8 ± 5.4	12.0 ± 5.4	0.215
8–12 Hz (μV²×s)	6.2 ± 3.0	6.4 ± 3.7	0.535
12–18 Hz (μV²×s)	2.7 ± 1.2	3.0 ± 1.3	0.005
18–32 Hz (μV²×s)	1.7 ± 0.8	2.1 ± 0.9	0.008
Actigraphy (n = 14)
Total sleep time (min), mean six nights	377 ± 56	370 ± 43	0.445
Total sleep time (min), polysomnogram night	422 ± 42	404 ± 41	0.117
Sleep efficiency (%), mean six nights	82.6 ± 7.5	82.0 ± 6.7	0.655
Time in bed (min)^b	456 ± 46	454 ± 37	0.836
Mid-sleep (hh:min)^b	03:48 am ± 00:23	03:47 am ± 00:19	0.836
Questionnaires
Pittsburgh Sleep Quality Index^c	4.2 ± 1.6	3.4 ± 1.8	0.059
Epworth Sleepiness Scale^c	5.6 ± 3.6	6.4 ± 3.4	0.133
Awakened by noise? (yes)^d	1/16	12/15	<0.001
Number tones heard?^d	3 (n = 1)	11.1 ± 8.9	n/a
Estimated sleep hours	7.3 ± 1.1	5.2 ± 2	<0.001
Estimated sleep quality	7.4 ± 1.7	5.5 ± 2.7	0.02
Stanford Sleepiness Scale	2.0 ± 0.9	2.8 ± 1.8	0.16

^aMedian ± interquartile range; P-value is for related-samples Wilcoxon signed rank test.

^bn = 17.

^cCompleted during daytime 5–14 days prior to polysomnogram nights.

^dNot all participants answered this question.