Cortisol dynamics and sleep quality: the role of sex and oral contraceptive use 113 Table 4.1. Demographic and clinical characteristics and the CAR outcomes of study participants. Naturally cycling (NC) women Oral contraceptive (OC) users Men n 87 31 124 Age Median, 1st and 3rd quartile 24.2 (21.3 to 26.6) 24.0 (21.8 to 28.5) 25.5 (23.3 to 31.2) Cohabitation status a. Single, n (%) 67 (77%) 25 (80%) 65 (52%) Living together, n (%) 15 (17%) 5 (16%) 28 (23%) Married, n (%) 4 (5%) 0 (0%) 15 (12%) Parity Has children, n (%) 7 (8%) 0 (0%) 17 (15%) Education score Median, 1st and 3rd quartile, n 5 (4 to 5), n=89 5 (4 to 5), n=32 5 (3 to 5), n=122 BMI Median, 1st and 3rd quartile 23.1 (21.3 to 25.3) 21.7 (20.7 to 23.5) 23.5 (22.3 to 25.6) Smoke status Current smoker, n (%) 7 (8.0%) 5 (16.1%) 13 (10.5%) MDI score Median, 1st and 3rd quartile , n 5 (3 to 7), n=90 5 (3 to 7), n=32 5 (2 to 7), n=124 Cohens PSS score Median, 1st and 3rd quartile , n 7 (2 to 12), n=84 8 (4 to 10), n=29 7 (4 to 11), n=118 CAR measurement day a. Work day, n (%) 27 (31.0%) 5 (16.1%) 39 (31.5%) Study day, n (%) 31 (35.6%) 5 (16.1%) 24 (19.4%) Day off, n (%) 23 (26.4%) 18 (58.0%) 54 (43.5%) Absolute awakening value (nmol/L) Mean, Standard deviation 11.53 (5.21) n=84 11.48 (6.58) n=31 9.77 (5.14) n = 122 CAR AUCi (nmol/L*minutes) Mean, Standard deviation 248.8 (304.3) n=84 14.6 (197.2) n=28 106.8 (220.9) n=117 Estimated group difference in CAR AUCi (nmol/L*minutes) Covariate-controlled model b. B (95% CI), p Reference -244.3 (-375.0 to -113.7) p<0.005 -146.1 (-246.2 to -46.0) p<0.005 a. Measurement day was missing in 15 participants. b. Adjusted for age, smoking and CAR sampling day (work day, free day, test day) and cortisol analysis batch. BMI = Body Mass Index; MDI = Major Depression Inventory; PSS = Perceived Stress Index; CAR = Cortisol Awakening Response; AUCi = Area Under the Curve with respect to increase. 3.2. Sleep quality and sleep disruptions The left panel of Figure 4.1 shows the distribution of the sleep quality scores, as measured using the PSQI sum score, per group. The mean PSQI sum score was estimated to be 3.6 (SD 1.7) among NC women and 4.6 (SD 2.5) among OC users, leading to an estimated mean difference of 0.97 (95% CI [0.14-1.81], p=0.023) between the NC women and OC users, with an estimated difference of 0.99 in the age-corrected model (95% CI [0.15-1.82], p=0.021, padjusted=0.042). The mean PSQI sum score was estimated to be 4.0 (SD 2.5) in the men, leading to an estimated mean difference of 0.35 (95% CI [-0.20 - 0.92], p=0.21) with the NC women. The outcomes of the marginal and age-corrected analyses are reported in Table 4.2.
RkJQdWJsaXNoZXIy MTk4NDMw