Table 3.
SHHS Mean Sleep Onset Latency in Minutes£
| Habitual HABSOL |
AM Estimated AMSOL |
Polysomnogram PSGSOL |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | SD | N | Mean | SD | N | Mean | SD | N | |
| Gender | |||||||||
| Male | 14.5 | 2.4 | 946 | 19.6 | 2.4 | 940 | 15.6 | 2.3 | 783 |
| Female | 17.3‡ | 2.5 | 1,051 | 22.0† | 2.7 | 1,043 | 16.1 | 2.4 | 902 |
| Ethnicity | |||||||||
| Caucasian | 14.7 | 2.4 | 1,482 | 19.9 | 2.6 | 1,468 | 15.2 | 2.2 | 1,332 |
| Others | 19.9‡ | 2.5 | 515 | 23.8† | 2.5 | 515 | 18.9‡ | 2.5 | 353 |
| Age category | |||||||||
| ≤67 years | 15.1 | 2.4 | 1,085 | 18.3 | 2.5 | 1,080 | 15.56 | 2.42 | 877 |
| >67 years | 17.0† | 2.5 | 911 | 24.3‡ | 2.5 | 902 | 16.39 | 2.19 | 805 |
| BMI | |||||||||
| Nonobese (<30%) | 15.2 | 2.5 | 1,221 | 20.4 | 2.6 | 1,208 | 15.2 | 2.3 | 1,072 |
| Obese (>=30%) | 17.3‡ | 2.5 | 752 | 21.6† | 2.6 | 749 | 17.1† | 2.4 | 593 |
| Education | |||||||||
| <12 years | 18.2 | 2.6 | 242 | 25.1 | 2.6 | 240 | 19.7 | 2.2 | 172 |
| 12–16 years | 16.6 | 2.5 | 1,095 | 20.9 | 2.5 | 1,085 | 16.1 | 2.3 | 980 |
| >16 years | 13.0§ | 2.3 | 483 | 18.5* | 2.5 | 482 | 13.5* | 2.3 | 373 |
| Time Zone | |||||||||
| Pacific/Eastern | 16.5 | 2.5 | 964 | 22.3 | 2.6 | 947 | 15.1 | 2.3 | 939 |
| Mountain/Central | 15.4 | 2.4 | 1,033 | 19.6† | 2.5 | 1,036 | 17† | 2.4 | 745 |
| RDI4% | |||||||||
| <5 | 15.4 | 2.4 | 557 | 19.6 | 2.6 | 548 | 16.3 | 2.3 | 496 |
| 5-<15 | 16.3 | 2.4 | 771 | 21.4 | 2.5 | 767 | 15.8 | 2.3 | 664 |
| 15-<30 | 16.4 | 2.5 | 394 | 21.3 | 2.6 | 391 | 15.8 | 2.3 | 320 |
| >=30 | 15.4 | 2.6 | 252 | 21.1£ | 2.5 | 255 | 15.3 | 2.4 | 183 |
| Chronic Lung Disease | |||||||||
| No | 15.7 | 2.4 | 1,747 | 20.8 | 2.6 | 1,733 | 15.8 | 2.3 | 1,478 |
| Yes | 17.9† | 2.7 | 250 | 21.1 | 2.6 | 250 | 16.2 | 2.2 | 207 |
| Chronic Heart Disease | |||||||||
| No | 15.4 | 2.4 | 1,581 | 20.1 | 2.5 | 1,575 | 15.8 | 2.3 | 1,335 |
| Yes | 18.5‡ | 2.5 | 411 | 24.3† | 2.6 | 403 | 16.3 | 2.2 | 345 |
| Any Alcohol | |||||||||
| No | 16.0 | 2.5 | 1,835 | 21.1 | 2.6 | 1,831 | 16.2 | 2.3 | 1,540 |
| Yes | 15.4† | 2.4 | 142 | 17.5† | 2.5 | 145 | 12.4‡ | 2.2 | 125 |
| Any Caffeine | |||||||||
| No | 15.6 | 2.4 | 1,625 | 20.9 | 2.6 | 1,622 | 15.6 | 2.3 | 1,385 |
| Yes | 17.6† | 2.5 | 352 | 20.5 | 2.5 | 350 | 17.4 | 2.5 | 281 |
£
t-test was used to compare means between the two groups in gender, age category, ethnicity, BMI, time zone, any chronic lung or heart disease, and any alcohol or caffeine intake in each of the three sleep assessments. Comparisons between the 3 categories in education and RDI4% were made using one-way analysis of variance (ANOVA) in each of the 3 sleep assessments.
Means for HABSOL, AMSOL, and PSGSOL are presented here (values were log transformed for these tests, and converted back by taking the antilogarithm).
†
p-value <0.05 for t-test.
‡
p-value <0.0001 for t-test.
*
p-value <0.001 for ANOVA.
§
p-value <0.0001 for ANOVA.