Nonalcoholic fatty liver disease and serious liver damage still possible in patients with normal liver function tests

VCU study is important step in identifying and managing this common condition

RICHMOND, Va. – Patients with normal results from a laboratory test commonly used to detect liver abnormalities still could suffer from nonalcoholic fatty liver disease, one of the leading causes of chronic liver disease, according to a study by liver experts at Virginia Commonwealth University.

VCU researchers compared data from two sets of patients who had been diagnosed with nonalcoholic fatty liver disease � one group of 51 patients who had normal results on their alanine aminotransferase (ALT) liver function test and one group of 50 patients with elevated ALT results. They found severe liver damage resulting from NAFLD – including liver inflammation, fat deposits and accumulations of fibrous tissue – in both groups. 

"Many doctors are telling their patients with risk factors for NAFLD and abnormal liver ultrasound studies or liver enlargement but normal ALT levels that they do not have liver disease and have nothing to worry about.  While that may be true for some individuals, it is not true for others," says Dr. Arun J. Sanyal, chair of the Division of Gastroenterology, Hepatology and Nutrition in VCU's School of Medicine. "The absence of obvious symptoms and a low normal ALT value do not guarantee freedom from advanced stage chronic liver disease."

Dr. Sanyal will discuss the VCU findings on Monday, July 21, during a presentation at a two-day meeting on Obesity and the Metabolic Syndrome in Washington, D.C. The research was published in the June issue of Hepatology, the journal of the American Association for the Study of Liver Diseases.

Nonalcoholic fatty liver disease (NAFLD) refers to a range of conditions that resemble alcohol-induced damage to the liver, from simple fatty liver to the more serious liver diseases of steatohepatitis and advanced fibrosis to life-threatening cirrhosis.  NAFLD is found, however, in people who either do not drink alcoholic beverages or consume modest amounts of alcohol in quantities not believed to be harmful to the liver.

NAFLD can affect any age group, although it is found most frequently in people who are obese – with a Body Mass Index (BMI) in excess of 30.  According to Sanyal, approximately 30 percent of individuals who are obese have a fatty liver, and as many as 80 percent of those with a BMI greater than 35 have a fatty liver.  In the general population, the prevalence of NAFLD ranges from 13 percent to 15 percent, while that of nonalcoholic steatohepatitis ranges from 3 percent to 4 percent.  

VCU is recognized internationally for its research in the field of nonalcoholic fatty liver disease and obesity.

The latest retrospective study reviewed clinical records of patients at the VCU Medical Center liver clinics who had undergone liver biopsies between 1996 and 2002 or had been diagnosed with NAFLD, even though they had normal liver serum levels.  The degree of alcohol consumption was estimated from the clinical records. The average age of patients in the group with normal ALT levels was 53, and the average age of those with elevated ALT was 52. Women outnumbered men in both groups by about two-to-one, and the average weight of the patients in each group exceeded 200 pounds. 

Because normal liver serum levels and lack of symptoms are unreliable predictors of NAFLD, Sanyal suggests that clinicians screen for the condition in patients with enlarged livers, particularly those who also are obese or have diabetes. Individuals who have these conditions should consult their physicians about the possibility of having previously undiagnosed fatty liver or steatohepatitis.

About VCU and VCU Medical Center

Virginia Commonwealth University is a major, urban public research university with national and international rankings in sponsored research. Located in downtown Richmond, VCU enrolls more than 31,000 students in 226 degree and certificate programs in the arts, sciences and humanities. Sixty-seven of the programs are unique in Virginia, many of them crossing the disciplines of VCU’s 13 schools and one college. MCV Hospitals and the health sciences schools of Virginia Commonwealth University comprise VCU Medical Center, one of the nation’s leading academic medical centers. For more, see www.vcu.edu.