Half of overweight, obese adults may have fatty liver disease

The global prevalence of metabolic dysfunction-associated fatty liver disease, a newly proposed term for nonalcoholic fatty liver disease, is “astonishingly high,” the authors of a recent meta-analysis found.

Metabolic dysfunction-associated fatty liver disease (MAFLD) may affect about half of all overweight or obese adults globally, according to a recent study.

To estimate specifically in overweight and obese adults the global prevalence of MAFLD, a newly proposed term for nonalcoholic fatty liver disease (NAFLD), researchers conducted a systematic review and meta-analysis of studies published through November 2020. MAFLD includes more diagnostic criteria to work around limitations of the current definition of NAFLD, with a diagnosis based on detection of fatty liver by histology (biopsy); imaging or blood biomarker; and one of three criteria of overweight/obesity, type 2 diabetes, or evidence of metabolic dysregulation. Alcohol consumption and comorbidity of other liver diseases are not ruled out for diagnoses of MAFLD. The results of the meta-analysis were published early online Feb. 17 by Clinical Gastroenterology and Hepatology.

One hundred sixteen studies involving 2,667,052 patients who could be diagnosed as having MAFLD from the general population were included in the meta-analysis, with an estimated global MAFLD prevalence of 50.7% (95% CI, 46.9% to 54.4%) among overweight/obese adults. MAFLD prevalence varied substantially across countries and regions, from 22.3% (95% CI, 19.0% to 26.0%) in Thailand to 81.5% (95% CI, 79.3% to 83.5%) in Poland. Ultrasound was the most commonly used diagnostic technique and had a prevalence rate of 51.3% (95% CI, 49.1% to 53.4%). Men were more likely to have MAFLD than women (59.0% [95% CI, 52.0% to 65.6%] vs. 47.5% [95% CI, 40.7% to 54.5%]). The authors wrote that MAFLD prevalence rates are comparable to those based on classical NAFLD and non-NAFLD studies in the general population. The estimated pooled prevalences of type 2 diabetes and metabolic syndrome were 19.7% (95% CI, 12.8% to 29.0%) and 57.5% (95% CI, 49.9% to 64.8%), respectively.

The studies included in the meta-analysis were all cross-sectional or case-control in design, resulting in high heterogeneity in the pooled estimations, the authors noted. They also stressed the need for additional studies in patients with diabetes or other metabolic syndromes. “MAFLD has an astonishingly high prevalence rate in overweight and obese adults,” they wrote. “This calls for attention and dedicated action from primary care physicians, specialists, health policy makers and the general public alike.”