Aim: 

Obesity is a very serious problem even in children and adolescents.The purpose was to study cardiovascular autonomic regulation usingheart rate and blood pressure variabilities analyses in obese childrenand adolescents.

Methods: 

Twenty obese and 20 nonobese (control)subjects (12-18 years) were examined at rest in lying position. Evaluatedparameters: Heart rate variability (HRV): the mean R-R interval, rMSSD,pNN50, spectral powers in high (HF), low frequency (LF) bands andtotal power (TP); blood pressure variability (BPV): the mean systolicand diastolic blood pressure, spectral powers in low and high frequencybands. The spectral power in high frequency band of HRV (HF-HRV)was considered as an index of parasympathetic activity, the spectralpower in low frequency band of BPV (LF-BPV) was taken as an index ofsympathetic control.

Results: 

Obese subjects have significantly shortenedmean R-R interval and higher mean systolic and diastolic blood pressurecompared to controls. HRV parameters: The pNN50, rMSSD, logHF,logTP were significantly lower in obese compared to nonobese group. BPVparameters: No significant differences were found in these parameters.

Conclusion: 

Higher mean values of heart rate and blood pressure,decreased parasympathetic activity (? rMSSD, pNN50, logHF, logTP)without alteration in sympathetic vasomotor control - was found in obesechildren and adolescents. We suppose that impaired parasympatheticregulation is present before sympathetic dysfunction.