LAUSR

Background Poor sleep is a risk factor for cardiovascular diseases (CVDs). The underlying pathogenesis is not clear. Levels of inflammatory markers, such as C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-ɑ (TNF-ɑ), have been found to be elevated in patients with CVDs. Aim The study aimed to investigate the associations between sleep quality and serum inflammatory markers in a cohort of obese adults. Methods This was a second analysis of the data from the Midlife in the United States (MIDUS) study, a longitudinal study of a national (US) sample of adults. A total of 1255 participants completed comprehensive biological assessments. The associations between global sleep score and serum levels of inflammatory markers were analyzed. Results Univariate analysis showed that a higher global sleep score was correlated with lower age (r = −0.079, P= 0.009), higher BMI (r = 0.100, P= 0.001) and heavier perceived stress (r = 0.335, P<0.001). Multivariate linear regression analysis showed that the global sleep score was positively related to levels of IL-6 (Sβ=0.074, P=0.009), IL-8 (Sβ=0.089, P=0.002), TNF-ɑ (Sβ=0.0.082, P=0.005), E-selectin (Sβ=0.071, P=0.016) and intercellular adhesion molecule-1 (ICAM-1, Sβ=0.117, P<0.001) after adjustments were made for age, gender, race, marital status, education, current smoking status, physician-diagnosed CVDs and respiratory diseases, BMI and perceived stress. However, the global sleep score was not associated with serum IL-10 (Sβ=−0.021, P=0.463) and CRP (Sβ=0.035, P=0.059) levels after adjustments were made for these confounding factors. Conclusion Poor sleep is positively associated with serum inflammatory marker levels among obese adults. Sufficient sleep may be particularly important for obese adults to prevent CVDs.