Having both non-alcoholic fatty liver disease (NAFLD) and diabetes could be just as risky as having a hepatitis C virus (HCV) coinfection when it comes to long-term liver health, show findings from a new study published in Hepatology and reported by Diabetes in Control.

Dutch researchers say this is one of the first studies to measure the combined impact of non-alcoholic fatty liver disease and diabetes on a large population.

For the study, researchers in the city of Rotterdam closely followed the liver health of 3,041 Dutch people, ages 45 or older, for two years. They used abdominal ultrasounds to help evaluate liver stiffness and characterize potential fibrosis in study participants, as well as blood tests, medical history records and comorbidity histories to supplant their data.

At the end of the trial period, the researchers found that 35.5 percent of participants had fatty liver disease, and 5.6 percent had clinically relevant liver stiffness or liver fibrosis measures. Not surprisingly, people who tested positive for the hepatitis B virus (HBV) or hep C were five times more likely to have liver fibrosis than those who were uninfected.

However, researchers said they were surprised by new findings showing that participants who had both diabetes and a fatty liver also had a five-fold greater chance of having liver fibrosis.

The study adds to a growing body of research linking NAFLD to the risk of liver fibrosis. The new research also suggests that several modifiable risk factors (such as blood sugar) may be related to overall liver health.