Methods: Individual mREE data were available for 900 patients with cirrhosis (mean [±1SD] age 55.7±11.6 yr; 70% men; 52% south-east Asian) and 282 healthy controls (mean age 36.0±12.8 yr; 52% men; 18% south-east Asian). Metabolic status was classified using thresholds based on the mean±1SD of the mREE in the healthy controls. Comparisons were made between mREE and pREE estimates obtained using the Harris-Benedict, Mifflin, Schofield and Henry equations. Stepwise regression was used to build three new prediction models which included sex, ethnicity, body composition measures, and MELD scores.
Results: The mean mREE was significantly higher in patients than controls when referenced to dry body weight (22.43.8 cf. 20.82.6 kcal/kg/24hr; p<0.001); there were no significant sex differences. The mean mREE was significantly higher in Caucasian than Asian patients (23.1±4.4 cf. 21.7±2.9 kcal/kg/24hr; p<0.001). Overall, 37.1% of Caucasians and 25.3% of Asians were classified as hypermetabolic. The differences between mREE and pREE were both statistically and clinically relevant; in the total patient population, pREE estimates ranged from 501 kcal/24hr less to 548 kcal/24hr more than the mREE. Newly-derived prediction equations provided better estimates of mREE but still had limited clinical utility.
Conclusions: Prediction equations do not provide useful estimates of REE in patients with cirrhosis. REE should be directly measured.