Athetosis increases resting metabolic rate in adults with cerebral palsy

To determine whether resting metabolic rate (RMR) is higher or lower in adults with cerebral palsy compared with the RMR of control subjects and to further examine physical characteristics of cerebral palsy that might affect RMR.

Twenty-one adults with cerebral palsy (9 women, 12 men) were compared with 50 control subjects (25 men, 25 women) within the same age range (18 through 50 years). The following measurements were made: RMR by indirect calorimetry, anthropometrics, body composition, and habitual physical activity patterns. The study was conducted at the University of Vermont General Clinical Research Center and the Ball State University Human Performance Laboratory.

Mean values +/- standard deviations, t tests, Pearson product-moment correlation coefficients, analysis of covariance, and stepwise multiple correlation regression analysis were used to examine the relationships among variables of interest.

No significant differences were found in body weight, body mass index, fat mass, percentage body fat, and measured RMR between the two groups. The subjects with cerebral palsy were significantly shorter, had less fat-free mass, and expended fewer kilocalories in leisure time activities than the control subjects. After statistical adjustment for differences in fat-free mass, the subjects with cerebral palsy had a 14% (P < .001) higher adjusted RMR (1,742 kcal/day) compared with that of the control subjects (1,534 kcal/day). According to stepwise regression analysis, RMR was best predicted in the entire sample by fat-free mass and the presence or absence of athetosis (multiple R = .83, P < .001). The presence of cerebral palsy alone was not significantly correlated with RMR.

The increased energy requirements of adults with cerebral palsy can be partially explained by athetotic movements. In this sample, the presence of athetosis increased RMR by an average of 524 kcal/day.