Obstructive sleep apnea in obese children was associated with increased sympathetic heart activity, with oxygen desaturation index correlating with mean heart rate (r=0.19, p=0.009).
Observational (n=191)
Does obstructive sleep apnoea alter autonomic function in children with obesity?
In children with obesity, obstructive sleep apnea is associated with increased sympathetic tone, suggesting intermittent hypoxia contributes to autonomic dysfunction.
Obstructive sleep apnoea (OSA), common in children with obesity, is associated with cardiovascular morbidity. Autonomic dysfunction has been suggested to be a key player in the development of these complications. We investigated the relationship between obesity, OSA and sympathetic activity in children. 191 children with obesity were included and distributed into two groups: 131 controls and 60 with OSA. Beat-to-beat RR interval data were extracted from polysomnography for heart rate variability analysis. Urinary free cortisol levels were determined. Urinary free cortisol did not differ between groups and was not associated with OSA, independent of the level of obesity. Differences in heart rate variability measures were found: mean RR interval decreased with OSA, while low/high-frequency band ratio and mean heart rate increased with OSA. Heart rate variability measures correlated with OSA, independent of obesity parameters and age: oxygen desaturation index correlated with mean heart rate (r=0.19, p=0.009) and mean RR interval (r= −0.18, p=0.02), while high-frequency bands and low/high-frequency band ratio correlated with arterial oxygen saturation measured by pulse oximetry ( S pO 2 ) (r= −0.20, p=0.008 and r= −0.16, p=0.04) and S pO 2 nadir (r=0.23, p=0.003 and r= −0.19, p=0.02). These results suggest that sympathetic heart activity is increased in children with obesity and OSA. Measures of hypoxia were related to increased sympathetic tone, suggesting that intermittent hypoxia is involved in autonomic dysfunction.
Eyck et al. (Sat,) conducted a observational in Obesity and Obstructive Sleep Apnoea (n=191). Obstructive sleep apnoea vs. Obese children without obstructive sleep apnoea was evaluated on Heart rate variability and urinary free cortisol levels. Obstructive sleep apnea in obese children was associated with increased sympathetic heart activity, with oxygen desaturation index correlating with mean heart rate (r=0.19, p=0.009).