Table 4.
Cardiac autonomic measures derived from frequency domain analysis of heart rate variability recorded during undisturbed REM and NREM sleep on a baseline and anticipatory stress night in perimenopausal women with (N=22) and without (N=18) a diagnosis of insomnia.
| Group |
Baseline night Mean (SD) |
Stress night Mean (SD) |
Significant ANOVA
effects |
||||
|---|---|---|---|---|---|---|---|
|
| |||||||
| NREM | REM | NREM | REM | ||||
| HR (bpm) | Control | 61.2 (5.3) | 63.7 (6.6) | 63.0 (634) | 65.3 (6.0) | ◀ |
Night**
and Sleep stage*** |
| Insomnia | 63.1 (6.4) | 65.9 (5.9) | 64.7 (6.7) | 67.5 (6.8) | |||
|
| |||||||
| TP (ms2)† | Control | 383.4 (218.2) | 368.6 (350.7) | 381.0 (289.0) | 370.7 (371.2) | ◀ |
Night*
and Sleep stage** |
| Insomnia | 337.0 (355.3) | 271.6 (335.2) | 287.2 (254.6) | 200.2 (185.4) | |||
|
| |||||||
| HFa (ms2)† | Control | 80.8 (63.7) | 38.2 (45.8) | 77.1 (62.2) | 37.9 (32.1) | ◀ | Sleep stage *** |
| Insomnia | 72.1 (82.2) | 27.0 (36.4) | 64.6 (56.4) | 18.4 (13.7) | |||
|
| |||||||
| HFnp † | Control | 0.22 (0.09) | 0.11 (0.06) | 0.22 (0.09) | 0.11 (0.06) | ◀ | Sleep stage *** |
| Insomnia | 0.23 (0.07) | 0.11 (0.04) | 0.24 (0.08) | 0.10 (0.05) | |||
|
| |||||||
| HFpf (Hz) | Control | 0.24 (0.04) | 0.25 (0.04) | 0.25 (0.04) | 0.25 (0.04) | ||
| Insomnia | 0.25 (0.03) | 0.25 (0.04) | 0.25 (0.03) | 0.25 (0.04) | |||
*
, p<0.05;
**
, p<0.01;
***
, p<0.001. HR, heart rate; TP, total power; HF, high frequency (a= absolute integrated power; pf=peak frequency; np=narrow proportion calculated as the proportion of the absolute high frequency integrated power on the total power);
†
, analyses based on log-transformed data.