Clinical

Fatty liver disease may resolve with bariatric surgery-induced weight loss

Last Updated: 2008-12-26 8:00:16 -0400 (Reuters Health)

By Megan Rauscher

NEW YORK (Reuters Health) - In obese individuals, weight loss following bariatric surgery leads to significant improvement or complete resolution of non-alcoholic fatty liver disease (NAFLD) in the majority of patients, according to a systematic literature review and meta-analysis.

The prevalence of NAFLD, an emerging problem related to the obesity epidemic, is estimated to be around 70% in obese individuals and 85% to 95% in those who are morbidly obese, the research team notes in Clinical Gastroenterology and Hepatology.

They point out that weight loss achieved through bariatric surgery improves diabetes and hypertension in obese individuals. However, the overall effect of weight loss on NAFLD remains unclear.

To investigate, Dr. Gagan K. Sood from the University of Texas Medical Branch in Galveston and colleagues pooled the data from 15 studies on bariatric surgery and liver histology (766 paired liver biopsies total).

"Overall results are encouraging for improvement in liver disease associated with obesity," Dr. Sood commented to Reuters Health.

At the time of bariatric surgery, the mean BMI of the study subjects ranged from 43.9 to 56. At follow-up liver biopsies, the mean BMI ranged from 28.6 to 39 and the reduction in mean BMI ranged from 19.11% to 41.76%.

Steatosis alone was present initially in 637 of 766 biopsies (83.15%), and the pooled proportion of patients with improvement or resolution in steatosis after bariatric induced-weight loss was 91.6%.

Non-alcoholic steatohepatitis was present in 299 of 555 biopsies (53.8%) initially and the pooled proportion of patients with improvement or resolution of this component of NAFLD was 81.3%, the team reports.

Fibrosis was mentioned to be present in 300 of 460 initial biopsies (65.21%), with improvement or resolution seen in 65.5%.

"The most encouraging finding," the team writes, "is that a majority of patients experience complete resolution of NAFLD after bariatric surgery, and the risk of progression of inflammatory changes and fibrosis seems to be minimal."

However, "in view of the small sample size of individual studies, the presence of significant heterogeneity and publication bias in our meta-analysis, generalizability of the results may require confirmation in multicenter, large-scale, well-designed trials," they conclude.

Clin Gastroenterol Hepatol 2008.