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.

Metformin dose increase versus added linagliptin in non-alcoholic fatty liver disease and type 2 diabetes: An analysis of the J-LINK study

We validated the effect of linagliptin, an oral dipeptidyl peptidase-4 inhibitor, on nonalcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM). A total of 50 patients with NAFLD and T2DM treated with metformin were randomized (1:1) to metformin plus add-on linagliptin (linagliptin group) or to an increased dose of metformin (metformin group) for 52 weeks. The primary endpoint was change in hepatic steatosis from baseline to week 52 as quantified by unenhanced computed tomography imaging. Secondary endpoints included changes in the levels of anthropometric, biochemical and adipokinetic markers. The linagliptin group showed no statistically significant reduction in hepatic steatosis as compared to the metformin group (P = 0.97), although changes in hepatic steatosis were significantly correlated with decreased liver enzymes in both groups. Body weight was significantly reduced in the metformin group but not in the linagliptin group (P = 0.002). Serum leptin levels were significantly increased in the linagliptin group compared to the metformin group (P = 0.003), and were correlated with the changes body weight in whole samples. Adverse events were not different between the two groups (P = 0.78). Add-on linagliptin demonstrated a safe profile but was not superior to increased metformin in reducing hepatic steatosis.

Fatty liver in men is associated with high serum levels of small, dense low-density lipoprotein cholesterol

AIMS

Our study addressed potential associations between fatty liver and small, dense low-density lipoprotein cholesterol (sd-LDL-C) levels using a cross-sectional analysis.

METHODS

We enrolled 476 male subjects. Serum sd-LDL-C concentrations were determined using precipitation assays.

RESULTS

Subjects were divided into four groups based on triglyceride (TG) and LDL-C levels: A, TG < 150 mg/dl and LDL-C < 140 mg/dl; B, TG < 150 mg/dl and LDL-C ≥ 140 mg/dl; C, TG ≥ 150 mg/dl and LDL-C < 140 mg/dl; and D, TG ≥ 150 mg/dl and LDL-C ≥ 140 mg/dl. sd-LDL-C levels and the prevalence of fatty liver were significantly higher in groups B, C, and D than in group A. Subjects were also categorized into four groups based on serum sd-LDL-C levels; the prevalence of fatty liver significantly increased with increasing sd-LDL-C levels. Additionally, logistic regression analysis revealed an independent association between sd-LDL-C concentrations and fatty liver using such potential confounders as obesity and hyperglycemia as variables independent of elevated TG or LDL-C levels.

CONCLUSIONS

Fatty liver is a significant determinant of serum sd-LDL-C levels independent of the presence of obesity or hyperglycemia. Fatty liver may alter hepatic metabolism of TG and LDL-C, resulting in increased sd-LDL-C levels.

Association between changes in body composition and the increasing prevalence of fatty liver in Japanese men

AIM

Prevalence of fatty liver is increasing. In this study, to elucidate the factor that contributes most to recent increases in prevalence of fatty liver, we determined the independent predictors for the onset of fatty liver and compared these predictors between 2000 and 2005.

METHODS

Japanese persons, aged 30-74 years, who participated in regular health checks at Kagoshima Kouseiren Medical Health Care Center (10 336 persons in 2000 and 11 011 persons in 2005) were enrolled in the study. Diagnosis of fatty liver was performed by ultrasonography. Body fat percentage (BFP) was determined using a bipedal bioimpedance instrument.

RESULTS

The prevalence of fatty liver has increased between 2000 and 2005 in men (33.3 vs 38.5% in 2000 vs 2005, respectively, P < 0.0001), but not in women (21.3 vs 21.0%, P = 0.8101). Logistic regression analysis revealed that both body mass index (BMI) and BFP are independent predictors of fatty liver in both men and women. BMI did not change in either men (23.4 +/- 2.9 vs 23.8 +/- 3.0 kg/m(2), P = 0.0528) or women (22.8 +/- 3.1 vs 22.8 +/- 3.3 kg/m(2), P = 0.9862) during the survey period. In contrast, BFP increased in men (20.6 +/- 4.7 vs 22.3 +/- 5.0 kg/m(2), P = 0.0003), but not in women (27.4 +/- 5.5 vs 28.4 +/- 5.9 kg/m(2), P = 0.3993). There was no significant change in triglycerides and glucose levels.

CONCLUSION

These results suggest that altered body composition, particularly increased BFP without an increase in BMI, has developed in men and is strongly associated with the increasing prevalence of fatty live amongst Japanese men.