Cortisol, Perceived Stress, Sleep Quality, and Body Composition Associations in Black Young Adults

• Published in: Obesity (Silver Spring, Md.) Md.), 2023-11, Vol.31, p.239-239
• Main Authors: Koch, Hannah, Sims, Jesse, Pickett, Stephanie, Gold, Laurie, McNeil, Jessica
• Format: Article
• Language: English
• Subjects: African Americans; Body composition; Hormones; Sleep; Young adults
• ISSN: 1930-7381; 1930-739X

Background: The cortisol awakening response (CAR) and diurnal slope (DS) are metrics of the stress-sensitive hormone, cortisol. Young adults experience higher perceived stress (PS) and poor sleep, each of which is linked to a blunted CAR and flatter DS. Yet, little data exists on these measures in African American young adults, despite their higher risk of obesity. The purpose of this analysis is to examine the relationship between cortisol (DS and CAR), PS, and subjective sleep quality with 6-month changes in body mass and composition in African American young adults. Methods: In a repeated measures design, 13 African American young adults (11 females; age, 21 ± 2.4 years; height, 168 ± 10.7 cm; body mass, 71.1 ± 13.3 kg; body fat, 25.0 ± 12.0%) completed an initial (B) and 6-month (6 M) visit. At B, participants completed measures of PS, subjective sleep quality, and salivary cortisol was collected at wake, 30-, 45-min post-wake, 12 µm, and 7 µm. CAR area under the curve (AUC) was calculated via trapezoidal integration with the wake, 30-, and 45-min post-wake samples using two metrics: with respect to wake (AUCi) and with respect to ground (AUCg). DS was calculated as the slope using wake, 12 µm, and 7 µm samples. Body mass, fat mass (FM), and fat free mass (FFM) were assessed at B and 6 M via BodPod. Paired t-tests evaluated differences in body mass and composition between B and 6 M. Spearman's Rho assessed the relationship between cortisol metrics, PS, and sleep at B with 6-month changes in body mass and composition. Results: There was a significant increase in body mass (MD: 2.6 kg, 95%CI [0.79, 4.46], p = 0.01) but no significant change in FM (MD: 2.4 kg, p = 0.06) or FFM (MD: 0.2 kg, p = 0.83) from B to 6 M. There were no significant associations between CAR-AUCi (r = 0.43), CARAUCg (r = 0.46), DS (r = 0.01), PS (r = 0.11), or sleep (r = 0.04) with body mass or body composition changes (all p's > 0.05). Conclusions: Despite an increase in body mass over 6 months in this sample, these changes were not significantly associated with CAR, DS, PSS, or subjective sleep quality at B.