Fatty liver disease is quite prevalent among adults in the United States, according to a recent study. Further, Latinos have a higher chance of developing this condition, while Asians have a greater risk of lean fatty liver disease. The study was published in Clinical Gastroenterology and Hepatology.

The accumulation of fat in the liver—which includes non-alcoholic fatty liver disease (NAFLD), the more severe non-alcoholic steatohepatitis (NASH) and alcohol-related fatty liver disease—is responsible for a growing proportion of advanced liver disease worldwide. Fatty liver disease can lead to liver inflammation, advanced fibrosis, cirrhosis and liver cancer.

To diagnose this condition, a noninvasive technique called transient elastography, or FibroScan, is used. These measurements are further enhanced with the inclusion of the controlled attenuation parameter (CAP) score, which measures the intensity of sound waves as they travel through fatty tissue compared with normal liver tissue.

Donghee Kim, MD, PhD, of Stanford University School of Medicine, and colleagues determined the prevalence of fatty liver disease and fibrosis in the United States as diagnosed using transient elastography and CAP scores.

They analyzed data from the 2017 to 2018 National Health and Nutrition Examination Survey. The final study population included 4,599 adults for whom liver stiffness and CAP data were measured. The average age was 46.6 years, with men and women about equally represented. The team was unable to classify these participants as having non-alcoholic or alcoholic fatty liver disease.

After adjustments for age, the researchers found fatty liver disease in 48% of all participants. The prevalence of the condition differed across age groups: 36% among those ages 18 to 39 years, 56% among those ages 40 to 59 years and 57% among those who were 60 years or older.

The occurrence of fatty liver disease also varied depending on the participants’ race or ethnicity and was highest among Latinos (57%), followed by Asians (48%), whites (47%) and Blacks (40%). Additionally, men were more likely than women to have fatty liver disease.

Among those with fatty liver disease, 14% of people showed signs of fibrosis, after adjusting for age. Suspected fibrosis was found in 17% of Latinos, 14% of whites, 12% of Blacks and 11% of Asians (11%). Men had a higher prevalence than women, except among Blacks.

After adjusting for age, some 4.4% of people with fatty liver disease had suspected cirrhosis, with a higher prevalence in whites (5.2%) and Latinos (4.5%).

The researchers also noted a link between race or ethnicity, being overweight or obese and the likelihood of having fatty liver disease. For instance, Asians were more likely to have fatty liver disease despite being lean. Overall, individuals with obesity and fatty liver disease were more likely to show signs of fibrosis and cirrhosis.

However, after calibrating the data for sensitivity and specificity and adjusting for age, the researchers found that the overall prevalence of fatty liver disease was 35%, with similar rates across sex, race or ethnicity and weight categories.

“Fatty liver disease and related hepatic fibrosis are highly prevalent in [the] U.S. general population,” concluded the researchers. “Considerable variations in fatty liver disease by sex and by race/ethnicity were noted, with men and Hispanics being disproportionally affected and non-Hispanic Blacks having a lower burden of disease.”

Click here to read the abstract in Clinical Gastroenterology and Hepatology.

Click here to learn more about fatty liver disease.