People with nonalcoholic fatty liver disease (NALFD) who consume alcohol in modest amounts are half as likely to develop hepatitis as non-drinkers with the same condition, reports a national team of scientists led by researchers at the University of California, San Diego School of Medicine. The findings are published in the April 19, 2012 online issue of The Journal of Hepatology.
NALFD is the most common liver disease in the United States, affecting up to one third of American adults. It’s characterised by abnormal fat accumulation in the liver. The specific causes are not known, though obesity and diabetes are risk factors. Most patients with NAFLD have few or no symptoms, but in its most progressive form, known as nonalcoholic steatohepatitis or NASH, there is a significantly heightened risk of cirrhosis, liver cancer and liver-related death. NALFD is also a known risk factor for cardiovascular disease (CVD). Patients with NAFLD are approximately two times more likely to die from coronary heart disease than from liver disease. The study’s authors investigated whether the well-documented heart-healthy benefits of modest alcohol consumption outweighed alcohol’s negative.
“We know a 50-year-old patient with NAFLD has a higher risk of CVD,” said Jeffrey Schwimmer, MD, associate professor of clinical pediatrics at UC San Diego, director of the Fatty Liver Clinic at Rady Children’s Hospital-San Diego and senior author. “Data would suggest modest alcohol consumption would be beneficial (in reducing the patient’s CVD risk) if you don’t take liver disease into account. When you do take liver disease into account, however, the usual medical recommendation is no alcohol whatsoever.”
“Our study showed that those people with modest alcohol intake - two drinks or less daily - had half the odds of developing NASH than people who drank no alcohol,” said Schwimmer. “The reasons aren’t entirely clear. It’s known that alcohol can have beneficial effects on lipid levels, that it increases ‘good’ cholesterol, which tends to be low in NAFLD patients. Alcohol may improve insulin sensitivity, which has a role in NAFLD. And depending upon the type of alcohol, it may have anti-inflammatory effects.”
The study also found that in patients with NAFLD, modest drinkers experienced less severe liver scarring than did lifelong non-drinkers.
The paper is based on analyses of 600 liver biopsies of patient’s with NAFLD by a national panel of pathologists who had no identifying clinical information about the samples. The study excluded anyone who averaged more than two alcoholic drinks per day or who reported consuming five or more drinks in a day (binge-drinking) at least once a month. All of the patients were at least 21 years of age.
Schwimmer said the findings indicate patients with liver disease should be treated individually, with nuance. “Forty million Americans have NAFLD. Physicians need to look at their patient’s overall health, their CVD risk, their liver status, whether they’re already drinking modestly or not. They need to put all of these things into a framework to determine risk. I suspect modest alcohol consumption will be an appropriate recommendation for many patients, but clearly not all,” he said.
Source: Winston Dunn, Arun J. Sanyal, Elizabeth M. Brunt, Aynur Unalp-Arida, Michael Donohue, Arthur J. McCullough, Jeffrey B. Schwimmer. Modest alcohol consumption is associated with decreased prevalence of steatohepatitis in patients with nonalcoholic fatty liver disease (NAFLD). Journal of Hepatology, 2012; DOI: