NEW YORK (Reuters Health) - Nearly two thirds of patients with chronic hepatitis C infection may have abnormal blood sugar levels, according to a report in the American Journal of Gastroenterology.

Blood sugar, or "glucose," abnormalities "are common and easily underestimated among patients with chronic hepatitis C infection," Dr. Ming-Lung Yu from Kaohsiung Medical University, Taiwan told Reuters Health. Careful evaluation for undetected glucose abnormalities is "essential" in caring for chronic hepatitis C patients.

Yu and colleagues compared the prevalence and characteristics of glucose abnormalities among 522 chronic hepatitis C patients and a comparison group of 447 without hepatitis C infection ("controls"), based on the results of an oral glucose tolerance test.

After excluding the subjects who were known to have diabetes, just over one third of the hepatitis C patients (34.2 percent) had normal results on the oral glucose tolerance test, the authors report, whereas 42.8 percent had impaired glucose tolerance and 23.0 percent had undiagnosed diabetes.

In contrast, 64.7 percent of the controls had normal levels of glucose, 32.4 percent had impaired glucose tolerance, and 2.9 percent had diabetes.

A family history of diabetes, male gender, advanced fibrosis stage of hepatitis, and increasing age each increased the risk of having glucose abnormalities, according to additional analyses.

Two consecutive fasting plasma glucose measurements or randomly measured glucose levels greater than 200 milligram per decaliter were not sufficient to confirm glucose abnormalities in the patients with chronic hepatitis C infection, Yu noted.

"Since family history, insulin resistance, age, and obesity are predisposing factors associated with diabetes in chronic hepatitis C patients, we would recommend an oral glucose tolerance test for chronic hepatitis C patients who are older than 40 years old," have a family history of diabetes or who are overweight, Yu advised.

SOURCE: American Journal of Gastroenterology, August 2008.

• More News on Hepatitis C

Related MedlinePlus Pages:

• Hepatitis C