Sleep‐disordered breathing and cardiometabolic and inflammatory markers in children with overweight/obesity: The role of cardiorespiratory fitness

Summary Objectives To investigate the association of sleep‐disordered breathing (SDB) severity with cardiometabolic and inflammatory markers independently of the adiposity levels; and to explore the role of cardiorespiratory fitness in these associations in children with overweight/obesity. Methods A total of 109 children aged 8–11 years with overweight/obesity were included in this cross‐sectional study. SDB was assessed using a scale of the reduce version of the Paediatric Sleep Questionnaire. Cardiometabolic markers included fasting blood lipids biomarkers (i.e., low‐ and high‐density lipoprotein cholesterol, and triglycerides), blood pressure, insulin, glucose, and the homeostatic model assessment index. Inflammatory markers (i.e., interleukin‐6, interleukin‐1β, C‐reactive protein [CRP], and tumour necrosis factor alpha) were analysed. Cardiorespiratory fitness was assessed by the 20 m shuttle‐run test. Results No significant associations were found between SDB severity and most of the cardiometabolic markers after correcting for adiposity and multiple comparisons (all p 's >0.05). SDB severity was positively related to CRP ( β = 0.352, p = 0.002), yet not with the remaining inflammatory markers analysed. The interaction effect of cardiorespiratory fitness presented a positive trend in the association of SDB with CRP ( p = 0.1). When stratified analyses by cardiorespiratory fitness levels were conducted, a positive relation was found between SDB and CRP in the low cardiorespiratory fitness group ( β = 0.465, p = 0.014), but not in the high cardiorespiratory fitness group ( β = 0.236, p = 0.108). Conclusion SDB severity was positively associated with CRP independently of the adiposity levels, but not with other inflammatory or cardiometabolic risk factors in children with overweight/obesity. Moreover, our results suggest that higher levels of cardiorespiratory fitness may attenuate the adverse effect of SDB severity on systematic inflammation in children with overweight/obesity.