Nonalcoholic Fatty Liver Disease in The Rotterdam Study: About Muscle Mass, Sarcopenia, Fat Mass, and Fat Distribution.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide. Obesity is a major risk factor for NAFLD and recently, low skeletal muscle mass emerged as additional risk factor for NAFLD. However, the different contributions of body mass index (BMI) to the risk of NAFLD are not yet well-known. We therefore studied body composition and muscle function with NAFLD in an elderly population-based study. Participants of European descent underwent dual-energy X-ray absorptiometry (DXA) and hepatic ultrasonography. NAFLD was defined as liver steatosis in absence of secondary causes for steatosis. Skeletal muscle index (SMI) was defined as appendicular lean mass/height2 and (pre)sarcopenia was defined using the European Working Group on Sarcopenia in Older People (EWGSOP) consensus guidelines. All analyses were stratified by sex and BMI (cut point: 25 kg/m2 ) and adjusted for age, weight, height, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides, and android-fat-to-gynoid-fat ratio (AGR). We included 4609 participants, of whom 1623 had NAFLD (n = 161 normal-weight and n = 1462 overweight). Presarcopenia and sarcopenia prevalence was low (5.9% and 4.5%, respectively) and both were not associated with NAFLD. SMI was associated with less NAFLD in normal-weight women (OR, 0.48; 95% CI, 0.29 to 0.80). A similar association for SMI and NAFLD was seen in normal-weight men, but significance dissipated after adjustment for AGR (OR, 0.63; 95% CI, 0.39 to 1.02). Generally, fat mass was a better predictor for NAFLD than lean mass. In particular, android fat mass was associated with all NAFLD subgroups (OR from 1.77 in overweight men to 8.34 in normal-weight women, pmax = 0.001), whereas substitution of gynoid fat mass for other body components had a significant protective association with NAFLD in every subgroup, but normal-weight men. Likewise, AGR was the best performing predictor for NAFLD prevalence (OR from 1.97 in normal-weight men to 4.81 in normal-weight women, pmax < 0.001). In conclusion, both high fat mass and low SMI were associated with normal-weight NAFLD. However, fat distribution (as assessed by AGR) could best predict NAFLD prevalence. © 2019 American Society for Bone and Mineral Research.

A model including sarcopenia surpasses the MELD score in predicting waiting list mortality in cirrhotic liver transplant candidates: A competing risk analysis in a national cohort.

BACKGROUND & AIMS: Frail patients with low model for end-stage liver disease (MELD) scores may be under-prioritised. Low skeletal muscle mass, namely sarcopenia, has been identified as a risk factor for waiting list mortality. A recent study proposed incorporating sarcopenia in the MELD score (MELD-Sarcopenia score). We aimed to investigate the association between sarcopenia and waiting list mortality, and to validate the MELD-Sarcopenia score (i.e. MELD + 10.35 * Sarcopenia). METHODS: We identified consecutive patients with cirrhosis listed for liver transplantation in the Eurotransplant registry between 2007-2014 and measured skeletal muscle mass on computed tomography. A competing risk analysis was used to compare survival of patients with and without sarcopenia, and concordance (c) indices were calculated to assess performance of the MELD and MELD-Sarcopenia score. We created a nomogram of the best predictive model. RESULTS: We included 585 patients with a median MELD score of 14 (interquartile range 9-19), of which 254 (43.4%) were identified as having sarcopenia. Median waiting list survival was shorter in patients with sarcopenia than those without (p <0.001). This effect was even more pronounced in patients with MELD ≤15. The discriminative performance of the MELD-Sarcopenia score (c-index 0.820) for three-month mortality was lower than MELD score alone (c-index 0.839). Apart from sarcopenia and MELD score, other predictive variables were occurrence of hepatic encephalopathy before listing and recipient age. A model including all these variables yielded a c-index of 0.851. CONCLUSIONS: Sarcopenia was associated with waiting list mortality in liver transplant candidates with cirrhosis, particularly in patients with lower MELD scores. The MELD-Sarcopenia score was successfully validated in this cohort. However, incorporating sarcopenia in the MELD score had limited added value in predicting waiting list mortality. LAY SUMMARY: In this study among patients with liver cirrhosis listed for liver transplantation, low skeletal muscle mass was associated with mortality on the waiting list, particularly in patients who were listed with low priority based on a low MELD score. However, adding these measurements to the currently used system for donor and organ allocation showed no added value.