Table 3. Sleep evaluation using nocturnal polysomnography (PSG) after drinking four types of beverages in healthy subjects.
Data are expressed as mean ± standard error (n = 5). One-way repeated measures analyses of variance were used to compare the clinical data between the beverages. ∗p < 0.05, †p < 0.01, compared with water and beer, respectively.
| Water | Beer | Shochu | Sake | |
|---|---|---|---|---|
| Total PSG time (min) | 720 | 720 | 720 | 720 |
| Total sleep time (min) | 447.2 ± 38.6 | 488.2 ± 17.6 | 482.9 ± 41.3 | 451.1 ± 39.6 |
| Sleep latency (min) | 151.6 ± 18.4 | 159.5 ± 19.3 | 185.3 ± 49.1 | 143.0 ± 10.8 |
| REM sleep latency (min) | 152.0 ± 24.6 | 144.2 ± 18.6 | 74.3 ± 6.1∗,† | 77.9 ± 3.9∗,† |
| Stage 1 (min) | 25.2 ± 5.0 | 37.1 ± 9.6 | 27.1 ± 7.4 | 33.9 ± 9.1 |
| Stage 2 (min) | 262.4 ± 27.8 | 294.2 ± 9.7 | 298.0 ± 33.8 | 270.8 ± 40.7 |
| Stage 3 (min) | 32.3 ± 6.2 | 34.0 ± 6.7 | 33.5 ± 5.6 | 28.2 ± 6.2 |
| Stage 4 (min) | 45.0 ± 8.3 | 58.0 ± 12.3 | 38.2 ± 7.5 | 34.4 ± 12.5 |
| Stage REM (min) | 82.5 ± 14.4 | 89.1 ± 10.2 | 95.1 ± 8.9 | 96.3 ± 13.5 |
| Arousals index (the number per hour) | 9.2 ± 1.9 | 13.1 ± 3.5 | 10.4 ± 1.6 | 10.3 ± 2.8 |
| Sleep efficiency (%) | 62.1 ± 5.4 | 67.8 ± 2.5 | 67.1 ± 5.7 | 62.7 ± 5.5 |
| Apnea hypopnea index (the number per hour) | 2.0 ± 1.0 | 13.7 ± 13.1 | 1.8 ± 0.7 | 1.5 ± 0.6 |
| Snore (%) | 0.1 ± 0.1 | 0.5 ± 0.4 | 1.3 ± 1.0 | 1.7 ± 1.6 |
| Alpha wave (%) | 0.6 ± 0.3 | 0.5 ± 0.3 | 0.6 ± 0.3 | 0.3 ± 0.1 |
| Periodic limb movement (the number per hour) | 3.6 ± 3.4 | 2.6 ± 2.5 | 0.1 ± 0.1 | 0.1 ± 0.1 |
Notes.
- REM
- Rapid eye movement