Table 2.
Percent differences and 95% confidence intervals of diurnal salivary cortisol components comparing GUTS2 saliva sub study participants born between 1989 and 1995 to mothers who worked night shifts before pregnancy to those whose mothers did not work night shifts before pregnancy.
| Maternal history of night shift work before pregnancy | |||||||
|---|---|---|---|---|---|---|---|
| Never | Ever | Ever | Ever | ||||
| Participants | N = 122 | N = 233 Unadjusted | N = 233 MV model 1* | N = 233 MV model 2** | |||
| %D | 95% CI | %D | 95% CI | %D | 95% CI | ||
| Overall | |||||||
| Awakening level a | 0 (ref.) | 10.0 | (−3.0, 24.7) | 12.1 | (−1.1, 27.1) | 11.8 | (−1.4, 26.9) |
| Awakening response b | 0 (ref.) | −4.8 | (−24.7, 20.4) | −4.8 | (−24.7, 20.5) | −5.2 | (−25.1, 19.9) |
| Early decline c | 0 (ref.) | −2.6 | (−7.4, 2.4) | −2.6 | (−7.4, 2.5) | −2.6 | (−7.4, 2.5) |
| Late decline d | 0 (ref.) | 2.0 | (0.3, 3.8) | 2.0 | (0.3, 3.8) | 2.1 | (0.3, 3.8) |
| Night rise e | 0 (ref.) | 0.5 | (−21.7, 28.8) | −0.3 | (−22.2, 27.8) | −0.9 | (−22.6, 27.0) |
| AUC f | 0 (ref.) | 1.2 | (0.0, 2.5) | 1.6 | (0.3, 2.8) | 1.5 | (0.3, 2.7) |
| Overall slope g | 0 (ref.) | 0.8 | (−0.3, 1.9) | 0.7 | (−0.4, 1.9) | 0.7 | (−0.4, 1.9) |
| Overall slope without peak h | 0 (ref.) | 0.9 | (−0.4, 2.1) | 0.9 | (−0.4, 2.1) | 0.8 | (−0.4, 2.1) |
| Females | N = 78 | N = 172 | N = 172 | N = 172 | |||
| Awakening level a | 0 (ref.) | −0.3 | (−13.7, 15.2) | 0.5 | (−13.0, 16.1) | −0.1 | (−13.8, 15.8) |
| Awakening response b | 0 (ref.) | −6.0 | (−27.9, 22.4) | −4.6 | (−27.0, 24.6) | −4.6 | (−27.0, 24.7) |
| Early decline c | 0 (ref.) | 3.1 | (−2.6, 9.1) | 2.4 | (−3.3, 8.5) | 2.4 | (−3.3, 8.5) |
| Late decline d | 0 (ref.) | 0.9 | (−1.0, 2.9) | 1.2 | (−0.8, 3.2) | 1.2 | (−0.8, 3.2) |
| Night rise e | 0 (ref.) | 16.7 | (−14.8, 59.9) | 14.8 | (−16.0, 56.9) | 15.0 | (−15.9, 57.2) |
| AUC f | 0 (ref.) | 1.2 | (−0.2, 2.7) | 1.4 | (0.0, 2.8) | 1.4 | (−0.1, 2.8) |
| Overall slope g | 0 (ref.) | 1.4 | (0.1, 2.8) | 1.5 | (0.1, 2.9) | 1.5 | (0.1, 2.9) |
| Overall slope without peak h | 0 (ref.) | 1.3 | (−0.2, 2.8) | 1.4 | (0.0, 2.9) | 1.4 | (0.0, 2.9) |
| Males | N = 44 | N = 61 | N = 61 | N = 61 | |||
| Awakening level a | 0 (ref.) | 35.5 | (5.5, 74.0) | 38.6 | (7.8, 78.3) | 34.6 | (4.0, 74.2) |
| Awakening response b | 0 (ref.) | −8.7 | (−43.1, 46.7) | −11.6 | (−45.1, 42.3) | −12.9 | (−45.8, 39.8) |
| Early decline c | 0 (ref.) | −13.0 | (−21.5, −3.7) | −12.5 | (−21.1–3.2) | −12.5 | (−21.0, −3.1) |
| Late decline d | 0 (ref.) | 4.5 | (1.1, 8.1) | 4.6 | (1.2, 8.2) | 4.6 | (1.2, 8.2) |
| Night rise e | 0 (ref.) | −28.3 | (−54.6, 13.1) | −29.3 | (−55.3, 11.7) | −29.4 | (−55.3, 11.7) |
| AUC f | 0 (ref.) | 0.8 | (−1.5, 3.2) | 1.0 | (−1.4, 3.5) | 0.5 | (−2.0, 2.9) |
| Overall slope g | 0 (ref.) | −0.7 | (−2.6, 1.4) | −0.6 | (−2.6, 1.4) | −0.6 | (−2.6, 1.4) |
| Overall slope without peak h | 0 (ref.) | −0.3 | (−2.5, 2.1) | −0.3 | (−2.6, 2.0) | −0.4 | (−2.7, 2.0) |
Abbreviations: %D, Percent Differences; CI, confidence interval; AUC, area under curve
Adjusted for age at sample collection in years, wake-up sample within 15 min of waking up (yes/no), saliva collection characteristics (brushed, ate, drank, exercised, happy, worried), usual hours of sleep, last night’s hours of sleep, trauma score in last month (0,1, 2+ events), belonging to sexual orientation minority (yes/no); birth control (yes/no, in females only).
Additionally adjusted for maternal characteristics: maternal age at birth, BMI before pregnancy, smoking status before pregnancy (smoker, past smoker, never smoker), alternative healthy eating score (quintiles), physical activity (MET-hours/week; quintiles), husband’s education (< 2 yr college, 4 yr college, grad school), maternal lifetime history of depression diagnosis (yes/no), chronotype (definite morning type, intermediate, definite evening type).
Cortisol level at awakening.
Change from awakening to 45 min after awakening.
Change from 45 min after awakening to 4 h after awakening.
Change from 4 h after awakening to 16 h after awakening.
Change from 16 h after awakening to bedtime.
Differences in area under the curve, levels from wake up time to 16 h after awakening.
Change from awakening to bedtime.
Change from awakening to bedtime without morning peak (at 45 min).