People living with type 2 diabetes have a higher prevalence of chronic hepatitis B virus (HBV) than the overall population, according to a new study published in the Journal of Diabetes Investigation. However, researchers still do not know which health condition could be raising the risk of the other, Endocrinology Advisor reports.

For the study, scientists at Shanghai’s Jiao Tong University Affiliated Sixth People’s Hospital examined health reports from 381 Chinese people with adult-onset autoimmune diabetes (a more slowly progressing form of type 1 diabetes); 1,365 people with type 2 diabetes; and 1,365 controls without any metabolic disorder and investigated hepatitis B prevalence within each of these groups.

The researchers found that about 13.5 percent of people with type 2 diabetes in the cohort were living with chronic hepatitis B, compared with an HBV risk rate of 10 percent among the controls in the overall population. Researchers also found that people with type 2 diabetes had a much higher rate of chronic hepatitis B than all patients who reported normal hepatic function (13.3 percent compared with 8.8 percent).

Ultimately, study authors noted that the odds ratio of chronic hepatitis B increased about 1.5-fold in patients with type 2 diabetes compared with the control group—even after adjusting for age, gender, body mass index and hepatic function. However, chronic hepatitis B rates were not different for subjects with adult-onset autoimmune diabetes. 

So what does this mean for people living with type 2 diabetes—or for that matter, people living with chronic HBV? The report ends by saying much more research is needed to ascertain whether chronic hepatitis B increases the risk of type 2 diabetes or, conversely, whether type 2 diabetes may increase the risk of hepatitis B. For now, scientists have uncovered a correlation but not a definitive link between the two conditions.