Heart rate power spectrum analysis of autonomic dysfunction in adolescents with anorexia nervosa

Abstract
We studied autonomic modulation of heart rate in 8 females with anorexia nervosa (AN) using power spectral analysis (PSA) of heart rate variability in the supine and standing positions at baseline and after 2 weeks of intensive nutritional rehabilitation, and compared findings with healthy female control subjects. The results indicate that there is a decrease in sympathetic modulation of heart rate, evident by a deficit of low frequency (0.01–0.15 Hz) heart rate power in the supine position in AN compared with control subjects. In addition, parasympathetic modulation of heart rate failed to decrease with standing. A trend toward improvement in autonomic control of heart rate in adolescents with AN occurs in the supine position relatively early in weight rehabilitation. PSA is a sensitive, quantitative, and noninvasive means of determining autonomic control of heart rate and could be a useful tool in monitoring the health of patients with AN. © 1994 by John Wiley & Sons, Inc.