Table 4.
Multivariable Associates of Previous Night Sleep and the Following Day Nap Duration on Nap Night Sleep Duration Using Mixed Model Analysis in Health ABC Sleep Study Participants Who Reported Daytime Nap (n = 159)1
| Variable | Unit/Referent | Percentage difference in nighttime sleep duration1 per unit |
Percentage difference in nighttime sleep duration1 per unit |
||
|---|---|---|---|---|---|
| Demographics | (95% CI) | (unadjusted) | (95% CI) | adjusted for multiple variables2 | |
| Race | White | −5.4 | (−10.1, −0.7) | −8.1 | (−13.3, −2.9) |
| Gender | Male | 0.9 | (−3.5, 5.4) | 2.8 | (−1.8, 7.4) |
| Actigraphy measured sleep | |||||
| Previous night sleep duration | Hour | 1.6 | (0.8, 2.5) | 4.1 | (2.2, 5.9) |
| Previous night - Movement and fragmentation | 14.63 | 0.02 | (−1.0, 1.0) | −1.3 | (−2.8, 0.2) |
| Same day sleep (nap) duration | Hour | −2.5 | (−3.9, −1.2) | −10.2 | (−16.0, −4.3) |
| Previous night sleep duration × Nap duration | Hour | −0.1 | (−0.3, 0.1) | 1.3 | (0.4, 2.2) |
| Health variables | |||||
| Depression score | 3.83 | 0.2 | (−2.1, 2.4) | −1.0 | (−3.4, 1.4) |
| Bodily pain last 30 days | none | −1.8 | (−6.6, 3.1) | −1.5 | (−6.3, 3.2) |
| Respiratory symptoms | none | 4.4 | (−0.1, 8.8) | 4.0 | (−0.2, 8.3) |
| Self reported diabetes | none | −1.8 | (−7.7, 4.1) | −1.2 | (−6.8, 4.4) |
| Fatigue | 7.73 | −0.3 | (−2.5, 2.0) | −0.9 | (−3.2, 1.5) |
Total nighttime sleep on the night of the nap.
Fully adjusted mixed model included total nighttime sleep duration (hours from actigraphy), movement and fragmentation index (nightly actigraphy), age (years), race, gender, BMI (kg/m2), depression, mental status, bodily pain in the last 30 days (yes/no), cardiovascular disease at the year 6 visit (yes/no), self-reported respiratory symptoms (yes/no), self-reported diabetes (yes/no), times up each night, fatigue score. Only variables with a significance level of P ≤ 0.10 in univariate, logistic regression, or mixed-model analyses are shown here.
Units for continuous variables approximate 1 standard deviation; for dichotomous variables, the referent group does not have the characteristic.