Weight gain after hepatitis C cure is common

19 May 2020 Keith Alcorn
Originally published on www.infohep.org

Substantial weight gain is common after hepatitis C cure, an analysis of a large cohort shows, and around one in five people with normal body weight became overweight within two years, US Veterans Affairs researchers report in the Journal of General Internal Medicine.

Being overweight or obese is associated with an increased risk of raised blood pressure (hypertension), cardiovascular disease, type 2 diabetes and some types of cancer. Obesity (a body mass index above 30) is associated with a higher risk of all these conditions compared to being overweight (BMI 25-29.9) but being moderately overweight is nevertheless associated with an increased risk of serious health conditions.

Obesity is also a risk factor for non-alcoholic fatty liver disease, which may cause liver damage and partially reverse any improvement in liver health that results from curing hepatitis C.

Researchers from the US Veterans Affairs Cohort, which covers all US military veterans born between 1945 and 1965, identified 11,469 people with hepatitis C who started direct-acting antiviral treatment between January 2014 and June 2015 and who had two years of follow-up after achieving sustained virologic response.

They calculated the change in weight between the time of sustained virologic response and at a 2-year follow-up visit, and looked at changes in weight category between underweight, normal, overweight and obesity.

The cohort was 96% male, 65% were over 60 years old, 59% were white and 35% were black, and 42% had an alcohol use disorder and 38% had cirrhosis.

At the time of treatment initiation, 78% were classified as overweight or obese and 36% of the cohort was clinically obese.

Although average weight gain over two years was negligible (+0.44 lbs / 199g), this disguises the fact that 52% of the cohort gained weight, 19% gained at least 10lbs (4.5kg) and 10% of the cohort gained at least 16.5lbs (7.5kg).

Among those in the normal body weight range, 22% became overweight during follow-up and 16% of those in the overweight band became obese.

Weight gain was associated with a higher FIB-4 score (> 3.25) indicating advanced fibrosis (odds ratio 1.24, 95% CI 1.06-1.44), and cirrhosis (OR 1.2, 95% CI 1.08-1.31). Greater obesity was associated with higher odds of weight gain during follow-up; people with a BMI above 35 were 1.5 times more likely to gain weight than people with normal body weight.

Older age (> 65 years) and no alcohol use protected against weight gain.

A probability analysis showed that younger patients, with cirrhosis and obesity who had moderate alcohol use were most likely to gain weight.

The probability of gaining at least 10lbs (4.5kg) over two years after hepatitis C cure ranged from 12.7% in people with normal weight aged 65 or over, no alcohol consumption and no cirrhosis, to 34% in people aged 65 or below who were obese, had cirrhosis and used alcohol moderately.

Reasons for weight gain are unclear. Although curing hepatitis C may improve liver function in ways that lead to increased muscle mass, muscle tends to be replaced by fat in older people. Dietary and lifestyle factors are more likely to influence weight gain.

The authors stress that further weight gain in a cohort in which 78% were overweight at baseline raises the risk of obesity-related disease. Only 1% of obese patients lost weight and returned to the normal body weight range during follow-up and the investigators say that lifestyle and eating habits that led to obesity prior to treatment may reinforce any tendency to weight gain after curing hepatitis C.

The study authors recommend discussion of weight management and the importance of avoiding weight gain at the time of hepatitis C treatment initiation, as well as the need to moderate alcohol consumption.