Postprandial cardiac autonomic function in Prader-Willi syndrome.

Context Individuals with Prader-Willi syndrome (PWS) have a high cardiovascular risk, the mechanism of which is unclear. There may be dysfunction in the autonomic nervous system (ANS) in PWS. Objective To measure, as indicators of cardiac autonomic function, postprandial heart rate variability (HRV) and arterial stiffness in adults with PWS. Methods Ten adults with PWS were compared with 11 matched healthy obese subjects and 9 healthy lean subjects. Electrocardiographic traces and arterial stiffness were recorded over a period of 10minutes at -60, 0, 30, 60, 120 and 240minutes after consumption of a standardized 600-kCal breakfast. Frequency domain analysis was performed using fast Fourier transform to estimate power spectral density in the full spectrum and in low-frequency (LF 0 center dot 04-0 center dot 15Hz) and high-frequency (HF 0 center dot 15-0 center dot 40Hz) bands. Results ANCOVA revealed a reduced LF HRV meal response in adults with PWS compared with obese controls, with no differences in HF HRV, LF/HF ratio, heart rate, total power or arterial stiffness meal responses. Conclusions This study assessed cardiac autonomic function in adults with PWS compared with matched obese and lean subjects in response to a meal. Results suggest impaired postprandial ANS responsiveness in PWS, which could contribute to both the known increased cardiovascular risk and obesity.