Young Bariatric Surgery Patients Less Likely to Have Liver Disease

By David Douglas

December 13, 2016

NEW YORK (Reuters Health) - Many severely obese young patients reach the threshold for bariatric surgery before their liver is damaged, according to French researchers.

In a November 24 online paper in Gut, Dr. Pierre Bedossa of Beaujon Hospital, Leclerc and colleagues note that non-alcoholic fatty liver disease (NAFLD) is a frequent complication of morbid obesity, but the severity varies and the natural course is unclear.

To investigate further, the team examined liver biopsies obtained from 798 patients during bariatric surgery. Histology was compared with clinical, biological, anthropometrical and body composition characteristics.

Altogether 22% had no visible steatosis and a "presumably normal" liver. These patients were significantly younger than patients with NAFLD (37.0 versus 44.4 years). They were also more likely to be female.

However, despite the younger ages in the group without NAFLD, the duration of obesity was similar, because those with apparently normal livers had an earlier onset of obesity than those with NAFLD (at age 14.8 versus 20.0).

The trunk to limb fat mass ratio increased according to liver disease severity. Compared to 1.0 for presumably normal liver, the ratio was 1.21 with steatosis and 1.34 with non-alcoholic steatohepatitis (NASH).

Patients with NASH had lower percentages of total body fat mass (47.4%) than those with NAFLD (49.1%) or those with presumably normal liver (50.0%)

The researchers suggest that the apparent absence of damage may be due to younger patients having "higher subcutaneous adipose tissue expandability, with better ability to trap and retain free fatty acids in their subcutaneous adipose tissue."

This suggests, they say, "that adipose tissue's 'buffering capacity' to store excessive fat may be progressively lost with increasing age."

Commenting by email, Dr. Michel M. Murr, who wasn't involved in the study, told Reuters Health, "The findings will generate high levels of enthusiasm because of the potential to predict the severity of NAFLD/NASH with non-invasive methods (particularly given) that the prevalence of NAFLD is on the rise."

Dr. Murr, who is chief of surgery and director of bariatric surgery at Tampa General Hospital, Florida, concluded "As importantly, emerging data from our center and the authors' strongly suggest that bariatric surgery reverses NAFLD and early stages of fibrosis."

Dr. Bedossa did not respond to requests for comments.


Gut 2016.