Changes in body composition and low blood urea nitrogen level related to an increase in the prevalence of fatty liver over 20 years: A cross-sectional study.

AIM: Qualitative body composition (BC) change, characterized by the combination of visceral fat gain and muscle loss, is drawing attention as a risk factor for fatty liver (FL). The present study aimed to describe trends in BC change and its association with FL in the Japanese population. METHODS: Data from medical checkups carried out on 56 639 Japanese participants every 5 years from 1997 to 2017 were analyzed. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated using body mass index and body fat percentage. Subjects were divided into two groups according to deviations from the correlation line of FMI and FFMI as the reference: FMI-predominant BC and FFM-dominant BC. Fatty liver was determined using abdominal ultrasonography. RESULTS: The prevalence of FL significantly increased from 27.3% to 42.7% in men and from 18.0% to 25.5% in women. The prevalence of FMI predominance significantly increased from 33.6% to 43.9% in men and from 29.1% to 47.0% in women. Fat mass index predominance was independently associated with FL in men and women (odds ratio: 1.96 and 1.94, respectively). Serum blood urea nitrogen level was inversely associated with FL in men and women (0.958 and 0.961, respectively) and significantly decreased from 15.8 to 14.9 mg/dl in men and from 15.1 to 14.0 mg/dl in women. CONCLUSIONS: Increasing FMI-predominant BC and decreasing serum blood urea nitrogen level could account for the increase in the prevalence of FL over 20 years. We believe that these factors stem from current lifestyle habits in Japan.

Efficacy of rifaximin, a poorly absorbed rifamycin antimicrobial agent, for hepatic encephalopathy in Japanese patients.

AIM: Rifaximin is recommended as treatment for hepatic encephalopathy (HE) that targets intestinal bacterial flora. Although combined use with synthetic disaccharides is the standard of care worldwide, the therapeutic effects of rifaximin for overt encephalopathy (OHE) in Japanese patients have not been examined sufficiently. We examined the therapeutic effects of rifaximin for OHE in Japanese patients. METHODS: A total of 76 patients who developed OHE of West Haven grade II or higher at least once within the 12 months before starting rifaximin were included. Blood ammonia levels and the incidence of OHE during the 12 months before and after starting rifaximin therapy were compared in a before-and-after study. Rifaximin efficacy and predictors of efficacy were also examined. RESULTS: Post-treatment blood ammonia levels were significantly lower than pretreatment levels. The mean annual number of OHE incidents and intravenous branched-chain amino acid preparations used per patient were significantly lower after starting rifaximin therapy (2.51 vs. 0.76 times/year, p < 0.001; and 71.9 vs. 20.7 preparations/year, p = 0.003, respectively). The cumulative incidence of hospitalizations associated with HE significantly decreased after rifaximin therapy (hazard ratio 0.187; p < 0.001). The efficacy rate, defined as the proportion of patients without OHE during the administration of rifaximin for 1 year after starting rifaximin therapy, was 65.8%. Serum albumin ≥2.7 g/dl was an independent predictor of efficacy. CONCLUSION: Rifaximin was associated with decreased blood ammonia levels, lower incidence of OHE, and fewer hospitalizations in Japanese patients with HE. In addition, serum albumin level was an important predictor on efficacy of rifaximin.