The effects of obstructive sleep apnea on cardiovascular functioning in children with obesity

Background : Paediatric obesity and obstructive sleep apnea (OSA) may be associated with cardiovascular consequences and they may show the same common inflammatory and metabolic pathogenesis. Aim : to evaluate and to assess cardiovascular activity in children with obesity associated with OSA. Methods : Obese children (body mass index - BMI - percentile >95°) underwent to standard polysomnography in a standard laboratory setting, a blood sample for lipid profile and a 24-hour ambulatory blood pressure monitoring. It was calculated the Smoothness Index (SI) which is a parameter to evaluate the blood pressure variability. Results : We studied 38 children (mean age 10.04±3.2 years, 28 males), with a mean BMI of 27.57±4.02, a mean BMI percentile of 117.81±21.52. They had an apnea-hypopnea index of 11.98±20.49n/h, an overnight oxygen saturation of 96.74±2.47 %. They did not show the physiologic systolic nocturnal deep of blood pressure. SI was higher in children with apnea-hypopnea index (AHI) > 5 n/h. BMI percentile correlates positively with systolic blood pressure, diurnal and nocturnal, while HDL (high-density lipoprotein) plasma levels correlate inversely. Conclusions : preliminary data showed that obese children with OSA had a peculiar blood pressure profile since they did not show the physiologic nocturnal deep. Obese children with AHI > 5 n/h were exposed to a future major risk of cardiovascular consequences.