Energy expenditure and balance among long term liver recipients

Excessive weight gain in patients undergoing liver transplantation has been well documented. The etiology for this complication is not well defined, although it has a high prevalence in post-transplant patients. Reduced energy expenditure may be related to excessive weight gain. Thus, the assessment of the resting energy expenditure (REE) in this patient population is of utmost importance.

Therefore, patients who underwent liver transplantation had their REEs measured by indirect calorimetry (IC). These results were compared with the demographic, socioeconomic, clinical, anthropometric, dietary and lifestyle variables assessed by uni- and multivariate statistical analyses. The REEs were also compared to estimates using the Harris-Benedict formula, and the patients were classified as hypo-, normo- and hypermetabolic.

We evaluated 42 patients with an average of 6.5 years post-transplant and an REE of 1449.7 kcal/day (measured by IC) or 1404.5 kcal/day (predicted by the HB formula). There was great correlation between the methods, and the best predictors of REE were age, weight, amount of lean mass and amount of total body water. Excessive weight was observed in 57% of patients, and obesity was observed in 26.2%. Underreporting of energy intake was observed in 65.8% of patients, and most patients (92.7%) were classified as sedentary or less active. No patient was classified as hypometabolic.

These results indicate that hypometabolism should be discarded as cause of the high prevalence of overweight and obese patients in the population undergoing LT. However, energy consumption and low levels of physical activity may be risk factors.