Markers of altered cardiovascular autonomic function in overweight children

Autonomic dysfunction is known to be associated with sleep apnea and insulin resistance. With the growing prevalence of obesity, the common factor among subjects with sleep apnea and insulin resistance, we sought to determine how autonomic cardiovascular function is affected by the independent and combined effects of sleep apnea and insulin resistance at the early stage of these syndromes. In this study, we investigated the autonomic function of overweight-to-obese children with either sleep apnea or insulin resistance or both during supine and standing postures. Using computational models of heart rate and peripheral vascular resistance variability, we found that children with sleep apnea, regardless of the presence of insulin resistance, had higher peripheral vascular baroreflex gain. Furthermore, children with insulin resistance, regardless of the presence of sleep apnea, had decreased heart rate baroreflex gain from supine to standing, which was opposite to those without insulin resistance. In conclusion, we were able to detect altered autonomic function by sleep apnea and insulin resistance using markers derived from our computational models that based only on non-invasive measurements.