Table 2.
Sleep and heart rate variables (N=59).
|
|
Value, mean (SD) | |
|
|
Polysomnography | Fitbit |
| N1soa (clock time) | 23.4 (0.9) | 23.4 (2.4) |
| TSTb (hours) | 8.0 (1.7) | 7.8 (2.6) |
| REMdc (hours) | 1.7 (0.8) | 1.7 (0.7) |
| lightdd (hours) | 4.2 (1.1) | 4.4 (1.3) |
| deepde (hours) | 1.5 (0.6) | 1.3 (0.5) |
| WASOf (hours) | 0.4 (0.5) | 1.0 (1.1) |
| REMLg (minutes) | 76.3 (30.6) | 103.9 (59.7) |
| REMh in the first cycle (%) | 11.6 (8.1) | 15 (8.7) |
| HR10i REM (bpmj) | 60.9 (9.1) | 59.9 (8.2) |
| HR10 N1k (bpm) | 61.8 (9.2) | 59.2 (7.5) |
| HR10 N2l (bpm) | 56.6 (7.7) | 55.7 (7.0) |
| HR10 N3m (bpm) | 58.8 (8.8) | 57.2 (7.2) |
| HRvar10n REM (bpm) | 28.1 (90.8) | 6.4 (16.1) |
| HRvar10 N1 (bpm) | 48.7 (110.1) | 6.8 (16.7) |
| HRvar10 N2 (bpm) | 22.0 (76.7) | 4.7 (24.3) |
| HRvar10 N3 (bpm) | 25.4 (111) | 2.9 (12.9) |
aN1so: sleep onset with non–rapid eye movement (NREM) sleep stages 1 criteria.
bTST: total sleep time.
cREMd: rapid eye movement sleep duration.
dlightd: light sleep or NREM sleep stages 1+NREM sleep stages 2 duration, respectively.
edeepd: deep sleep or NREM sleep stages 3 duration, respectively.
fWASO: wakefulness after sleep onset.
gREML: rapid eye movement sleep latency.
hREM: rapid eye movement.
iHR10: 10%-trimmed heart rate average.
jbpm: beats per minute.
kN1: NREM sleep stages 1.
lN2: NREM sleep stages 2.
mN3: NREM sleep stages 3.
nHRvar10: 10%-trimmed heart rate variability.