Non-esterified fatty acid is being validated as a substitute measure for non-protein respiratory quotient in patients with cirrhosis

Abstract

Summary Background & aims A late evening snack (LES) is recommended for improving starvation state in cirrhotic patients. The non-protein respiratory quotient (npRQ) is an important index for evaluating the indications and effectiveness of LES. Indirect calorimetry is used to determine npRQ, but it is expensive and not available in many hospitals. The aim was to find blood biochemical markers reflecting npRQ. Methods A total of 183 cirrhotic patients (M/F = 149/34) were enrolled. For each patient, fasting state npRQ was determined by indirect calorimetry. The relationships between npRQ and indices such as age, body mass index, platelet count, etiology, and levels of aspartate aminotransferase, alanine aminotransferase, total bilirubin, albumin, blood glucose, and non-esterified fatty acid (NEFA) were statistically analyzed. Results There was a significant negative correlation between the measured npRQ and serum NEFA levels, and the NEFA level was the strongest predictor of npRQ. Multiple regression analysis identified that the NEFA and Hepatitis B virus were predictors of npRQ. Conclusion These data suggest that fasting serum NEFA level is the most relevant biomarker to determine npRQ if indirect calorimetry is unavailable. Thus, serum NEFA levels may be useful to determine the indications and effectiveness of LES therapy in cirrhotic patients.