Researchers trawled a surveillance database used for patients in receipt of Medicare funding for health care, to identify those aged 65 and older who had been diagnosed with liver cancer.

They found 2,061 patients with liver cancer on records spanning the five years between 1994 and 1999. They also randomly selected more than 6,000 other similarly aged patients from the database, who had not been diagnosed with cancer.

Male, Non-White Diabetics

They checked the claims records for known risk factors for liver cancer, including hepatitis C and B viral infections, alcoholic liver disease, and haemochromatosis (poor absorption and storage of iron). They also checked the claims records for diabetes.

Compared with patients who did not have the disease, those with liver cancer were around twice as likely to be male and of non-white ethnicity.

And the proportion of patients with diabetes was almost twice as high among those with liver cancer.

Hepatitis C Could Further Risk

After taking into account demographics and other major risk factors, the researchers concluded that diabetes almost tripled the risk of liver cancer.

But the findings also suggest that hepatitis C could also interact with diabetes to further boost the risk of developing liver cancer.

The authors suggest that diabetes might be an independent risk factor for liver cancer, rates of which have increased significantly in the US in recent years.