Prevalence of fatty liver and advanced fibrosis by ultrasonography and FibroScan in a general population random sample.

AIM

Fatty liver is the most common liver disease. This study examined fatty liver and advanced fibrosis prevalence in a random sample of the Japanese general population.

METHODS

A total of 6000 people randomly selected from two cities in Hiroshima Prefecture were invited to participate in this cross-sectional study originally carried out for hepatitis virus screening. Ultrasonography and FibroScan (controlled attenuation parameter [CAP] and liver stiffness measurement [LSM]) were provided as additional tests.

RESULTS

Of 6000 invited individuals, 1043 participated in hepatitis virus screening, of which 488 randomly selected individuals (median age, 56 years; interquartile range, 45-68 years; male participants, 49.8%) underwent ultrasonography, CAP, and LSM. Ultrasonography showed fatty liver in 24.6% and mild fatty liver in 32.8%. Controlled attenuation parameter showed severe steatosis in 27.5%, moderate steatosis in 12.5%, and mild steatosis in 11.1%. Overall, 62.1% were diagnosed with fatty liver based on ultrasonography or CAP. Nonalcoholic fatty liver disease (NAFLD) prevalence was 50.6%. Liver stiffness measurement found cirrhosis in 1.0% and severe fibrosis in 1.8%. Multivariate analysis of risk factors associated with ≥F2 or higher liver fibrosis showed that age ≥60 years and above (adjusted odds ratio [AOR], 3.2; 95% confidence interval [CI], 1.5-6.9; p = 0.0031), hepatitis C virus antibody positivity (AOR, 8.4; 95% CI, 1.0-68.4; p = 0.0467), and fatty liver (AOR, 2.3; 95% CI, 1.1-6.2; p = 0.0317) are independent risk factors.

CONCLUSIONS

In the general population, 62.1% had fatty liver, and NAFLD prevalence was twice as high as previously reported. Screening that is noninvasive, low-cost, and does not require special techniques or equipment is needed to detect advanced liver fibrosis.