Table 1.
Baseline Characteristics of Participants (Mean ± SD)
| YOUNG ADULT | OLDER | AGE CONTRAST | |
| Wake-up (questionnaire) | 7:31 ± 1:24 | 5:55 ± 1:18 | P < 0.001 |
| Actigraphic wake time | 8:32 ± 2:16 | 6:39 ± 1:07 | P < 0.001 |
| Bedtime (questionnaire) | 23:48 ± 1:03 | 22:51 ± 1:05 | P < 0.001 |
| Bedtime (actigraph) | 00:33 ± 1:31 | 22:41 ± 1:24 | P < 0.001 |
| Sleep log total sleep time | 444 ± 65 min | 406 ± 63 min | P = 0.003 |
| Actigraphic total sleep time | 404 ± 70 min | 385 ± 68 min | NS |
| aMT6s onset | 23:04 ± 1:45 | 22:16 ± 1:46 | P = 0.02 |
| aMT6s acrophase | 3:47 ± 1:37 | 3:18 ± 1:58 | NS |
| aMT6s offset | 08:22 ± 1:28 | 08:20 ± 2:11 | NS |
| Cortisol acrophase | 9:59 ± 1:54 | 8:29 ± 2:51 | P = 0.008 |
| Oral Temperature bathyphase | 04:04 ± 2:10 | 04:44 ± 3:52 | NS |
| PSQI total score | 3.8 ± 2.3 | 3.6 ± 2.7 | NS |
| CESD at intake | 7.0 ± 7.0 | 3.5 ± 3.6 | P = 0.002 |
NS = Not Significant. Temperature bathyphase: the fitted minimum, 180° from the acrophase.