Is Daytime Napping Associated With Inflammation in Adolescents?

Objective: Daytime napping has been associated with poor health outcomes in adults. It is not known whether daytime napping is similarly linked to adverse health in adolescents, although many report napping. The present study evaluated associations between daytime napping and 2 markers of increased inflammation, high-sensitivity C-reactive protein and interleukin-6 (IL-6), in healthy high school students. Methods: Two hundred thirty-four Black and White high school students completed a week of actigraph and diary measures of sleep and napping and provided a fasting blood sample. Napping measures were the proportion of days napped and the average minutes napped across 1 week during the school year. Results: Linear regressions adjusted for age, sex, race, average nocturnal sleep duration, time between sleep protocol and blood draw, and body mass index percentile demonstrated that proportion of days napped measured by actigraphy, B(SE) = .41(.19), p < .05, across the full week was positively associated with IL-6. Higher proportions of school days napped between 2 p.m. and 6 p.m., B(SE) = .40(. 20), p < .05, and between 6 p.m. and 10 p.m., B(SE) = .57(.28), p < .05, were associated with increased IL-6. No associations emerged between average actigraphy-assessed nap duration and either study outcome. Diary-reported napping was unrelated to either study outcome. Conclusions: Actigraphy-assessed napping and IL-6 are associated but the direction of the relationship remains to be determined. Overall, napping is an important factor to consider to better understand the relationship between short sleep and cardiovascular health in adolescents.