Spectral analysis of heart period variability in anorexia nervosa

Abstract

The aim of this study was to investigate the response of autonomic cardiac control to postural change using spectral analysis, in patients with anorexia nervosa. Spectral components of total variability as well as of low and high frequencies were analyzed for 17 anorexic patients with mean body mass index (14.9 ± 1.9) kg/m2 and for 9 healthy age-matched women with body mass index (20.3 ± 1.7) kg/m2, in supine and standing postures. During standing posture, increased heart rate in all subjects was accompanied by the decrease in total variability and high frequency spectral powers. In supine posture, anorexic patients demonstrated the reduced low frequency spectral power. Compared to control women, during standing posture anorexic patients showed higher heart rate, reduced total variability and high frequency spectral powers. Statistically significant correlation was noticed between body mass index and spectral power of low frequency in both supine and standing posture. Alterations in autonomic cardiac control induced by anorexia nervosa could be estimated by spectral analysis of heart period variability.

Keywords

• anorexia nervosa
• autonomic nervous system
• posture
• heart rate
• electrocardyography
• body mass index
• spectrum analysis