Abstract
The aim of this prospective study was to investigate the activity of the autonomic nervous system (ANS) during sleep in children with obstructive sleep apnea (OSA), in order to detect a precocious imbalance of ANS.
Materials and methods: A total of 43 subjects between 4 to 15 years of age (7.26 ± 2.8 years), undergoing a diagnostic assessment for OSA in our Paediatric Sleep Centre (Rome, Italy), for habitual snoring and apnea were enrolled.A time domain index (the R-apnea index) was developed to evaluate heart rate variability (HRV) strictly related to obstructive events during sleep. Moreover Poincaré plot of RR intervals during the whole night was calculated.
Results: The R-apnea index was negatively correlated with apnea hypopnea index (AHI) (r = -0.360, p = 0.028). Furthermore AHI and the duration of the disease have been identified as the only variables that were significantly correlated with the R-apnea index.
Three groups were subsequently created on the basis of polysomnographic findings according to AHI. The R-apnea index resulted significantly lower in patient with severe OSA compared to primary snoring/mild OSA subjects (p<0.05).
Looking at Poincaré plot, SD1 (short term variability) showed a diminishing trend with severity of OSA, although not reaching statistical significance.
Conclusions: Our findings suggest that an early autonomic impairment was present in children with OSA since HRV was altered in the very short term (R-apnea index) and in short term (SD1).
- © 2014 ERS