Parietal Fast Sleep Spindle Density Decrease in Alzheimer’s Disease and Amnesic Mild Cognitive Impairment
Table 2
Mean and standard errors of the polysomnographic variables of AD patients, amnesic MCI patients, and HC. The results of the one-way ANOVAs ( and values) were also reported, with post hoc unpaired -test ( values) when ANOVAs were significant (). Significant between-groups differences are indicated in bold.
Variables
AD
MCI
HC
AD versus MCI
AD versus HC
MCI versus HC
Mean (SE)
Mean (SE)
Mean (SE)
Stage 1 latency (min)
41.04 (9.78)
27.44 (4.88)
19.58 (5.86)
2.30
0.11
—
—
—
Stage 2 latency (min)
33.27 (8.61)
26.61 (4.32)
13.29 (4.58)
2.73
0.08
—
—
—
Stage 1 (%)
13.33 (3.06)
9.34 (1.44)
6.55 (1.33)
2.63
0.08
—
—
—
Stage 2 (%)
75.92 (3.33)
76.21 (1.88)
77.91 (2.10)
0.18
0.83
—
—
—
SWS (%)
0.08 (0.05)
0.14 (0.08)
0.79 (0.34)
3.73
0.03
0.53
0.05
0.07
REM (%)
10.66 (2.78)
14.28 (1.85)
15.22 (1.53)
1.29
0.28
—
—
—
WASO (min)
92.24 (14.25)
100.89 (14.06)
90.37 (8.98)
0.20
0.82
—
—
—
Awakenings (#)
18.13 (3.87)
21.33 (2.13)
20.13 (2.23)
0.32
0.73
—
—
—
Arousals (#)
40.00 (9.53)
32.73 (6.53)
34.40 (7.96)
0.22
0.80
—
—
—
TST (min)
263.82 (22.46)
274.31 (16.02)
303.36 (17.22)
1.19
0.31
—
—
—
TBT (min)
388.09 (20.91)
401.47 (9.60)
406.82 (13.52)
0.39
0.68
—
—
—
SEI% (TST/TBT)
67.56 (4.15)
68.31 (3.61)
74.13 (2.98)
0.99
0.38
—
—
—
SWS, slow-wave sleep; REM, rapid eye movement; WASO, waking after sleep onset; TST, total sleep time; TBT, total bed time; SEI, sleep efficiency index.