In the largest study of its kind, researchers have shown that diabetes can cause chronic liver disease and cancer of the liver.
Researchers from the Department of Veterans Affairs (VA) and the National Institutes of Health report their findings in the February issue of Gastroenterology. The prospective cohort study was comprised of 173,643 patients with diabetes and 650,620 patients without diabetes who were discharged from VA hospitals between 1985 and 1990.
These patients were tracked through 2000. Most were men (98 percent). The majority (99.5 percent) of diabetic patients had type II diabetes mellitus. Among diabetic patients, the incidence of chronic liver disease and cancer of the liver was about twice the incidence that of patients without diabetes.
A link between diabetes and liver disease was previously known; it was unknown whether diabetes caused liver disease or vice versa. Liver disease associated with diabetes is usually insidious, asymptomatic and goes undetected until a severe condition, such as liver cancer, occurs.
"Because of the significantly increased risk of developing liver disease, we recommend regular testing of liver enzymes for patients with diabetes," said study author Hashem El-Serag, from the Houston VA Medical Center. "For patients with diabetes who receive oral medications, there has been a concern about toxicity in the liver - more reason to test liver enzymes early on and then periodically thereafter."
The risk for developing liver disease and liver cancer is highest among patients with long-standing (10+ years since diagnosis) diabetes. The increased risk is independent of alcoholic liver disease, viral hepatitis and demographic features.