NASH, NAFLD Studies Finally Surpassing HCV Studies

Eyal Klang, MD

With more and more effective treatments for hepatitis C virus (HCV) infections available, more attention is being paid to diseases like non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH).

A team, led by Eyal Klang, MD, Diagnostic Imaging Department, Chaim Sheba Medical Center, analyzed trends in HCV and NAFLD research from 2000-2020 using text-mining strategies.

Rates Going in Opposite Directions

In recent years, the rate of HCV prevalence has decreased, largely because of direct-acting antiviral treatment.On the other hand, the prevalence of NASH and NAFLD are increasing with no US Food and Drug Administration (FDA) approved treatments available. The most common and effective treatment for the disease is lifestyle modification with diet and exercise.

Recently, investigators estimated the pooled prevalence of NAFLD to be 33.8%.

In the study, the investigators searched various databases for studies published between 2000-2020 and compared the total number of publications on both etiologies. They also performed subsanlyses for different terms of interest and geographic origin.

The team identified 75,934 HCV-related entries and 24,987 NASH or NAFLD-related entries during the 20 year study period.

Trends

The analysis show a linear upward slope in the number of HCV publications up to 2015 (154.9 publications/year, P <0.001).

However, beginning in 2015, the number of yearly HCV publications began to slope downward (−242.2 publications/year, P <0.001).

For NASH or NAFLD publications, the number of publications were on a continuous upward slope throughout the study period. The magnitude of the slope increased between 2000-2015 (114.2 publications/year, P <0.001) and between 2015-2020 (439.7 publications/year, P = 0.01).

“The number of NASH/NAFLD-related publications continuously rose during the study period, often parallel to the NASH/NAFLD prevalence and the awareness in countries where the epidemiological trends could be documented,” the authors wrote. “The number of annual publications relating to NAFLD/NASH therapeutics is still increasing and a multitude of pharmacological targets are currently in development.”

In addition, the number of NASH/NAFLD publications surpassed the number of HCV publications for the first time in 2020.

However, the NASH/NAFLD field does lack publications on screening and treatment methods.

The geographic results show the largest number of HCV-related publications were affiliated with research teams in the US. Other countries that ranked high included Japan, Italy, China, and France.

For NASH and NAFLD publications, the US and China generally had the most.

“Trends in publications varied between both etiologies. They reflect the success of antiviral treatment for HCV,” the authors wrote. “The growing rates of NAFLD/NASH and the lack of a targeted cure explain the rise in related publications.”

The study, “Research trends analysis of chronic hepatitis C versus nonalcoholic fatty liver disease: A literature review text-mining analysis of publications,” was published online in Health Science Reports.