Metabolically Associated Fatty Liver Disease (MAFLD), an updated term for non-alcoholic fatty liver disease (NAFLD), occurs in around half of all people with obesity or overweight worldwide, according to Clinical Gastroenterology and Hepatology.
Because of the accumulation of fat in the liver, NAFLD and its more severe form, alcohol-free steatohepatitis (NASH), are responsible for an increasing proportion of advanced liver disease. The condition is often associated with obesity and metabolic syndrome, which is reflected in the new term MAFLD. Inflammation can lead to the formation of scar tissue (fibrosis), cirrhosis (advanced scarring) and even liver cancer. Without effective approved medical therapies, disease management depends on lifestyle changes such as weight loss and exercise.
Qiuwei Pan, PhD, from Erasmus University Medical Center in Rotterdam, the Netherlands, and colleagues have scanned the Medline, Cochrane, Web of Science, Embase and Google Scholar databases from their launch until November 2020. The aim was to determine the worldwide prevalence of MAFLD in adults with obesity and overweight in the world population.
The team shortlisted 116 studies with 2,667,052 participants with overweight or obesity. Regardless of the diagnostic technique used, the global MAFLD prevalence was 51%. The rate was the same when looking at ultrasound diagnosis, the most common method. In all studies, the pooled prevalence of type 2 diabetes was 20% and the prevalence of metabolic syndrome was 58%.
The prevalence of MAFLD was significantly higher in men (59%) than in women (48%).
The MAFLD prevalence was high in all age groups. In people under 40 years of age, the prevalence was 41%; for people between 40 and 60 years of age it was 56%; and for those over 60 it was 52%.
Overall, MAFLD was widespread. South America had the highest prevalence at 71%, followed by Southern Europe, Eastern Asia, Western Europe, Southern Asia, Southeast Asia, North America, and Northern Europe. In all countries, the MAFLD prevalence ranged from 22% in Thailand to 82% in Poland. Surprisingly, the prevalence was similar in high-income and low- and middle-income countries.
“MAFLD has a surprisingly high prevalence rate in overweight and obese adults,” the researchers wrote. “This requires the attention and committed action of general practitioners, specialists, decision-makers in health policy and the public alike.”
Click here to read the abstract of the study in Clinical gastroenterology and hepatology.
Click here to learn more about fatty liver disease.