People who might be infected with the potentially fatal hepatitis C virus are not getting tested early or often enough, possibly because neither they nor their primary doctors are raising the issue, a new University of Michigan (U-M) Health System study finds. And even if they do test positive for the virus, they may not always get referred for specialty care.

The study's results suggest an urgent need for better awareness among both physicians and the public about the risk factors for hepatitis C. The authors say better mechanisms may be needed to help busy doctors identify those at risk and ensure they get tested while there is still time to refer them for treatment - treatment that may help them fight the infection and stave off liver failure.

The new study finds that among a sample of the 2,348 hepatitis C screening tests ordered by primary care physicians, only a quarter of the tests were ordered because the doctor identified the patient as having a potential risk factor, such as intravenous drug use or a blood transfusion before 1992. Another 65 percent had the test because of prior liver problems or because routine blood tests showed elevated liver enzymes. Ten percent of patients requested it.

Of all those tested, 10 percent turned out to be infected, and about half were referred to a specialist for follow-up. Meanwhile, almost half of the 57 patients who tested positive and went on to have a liver biopsy turned out to have significant liver scarring, either cirrhosis or fibrosis, suggesting a longstanding infection.

The results were presented May 21 at the Digestive Disease Week meeting in Atlanta, Georgia, by U-M Medical School gastroenterology professor Anna Lok, M.D., fellow Thomas Shehab, M.D., and visiting fellow Mauricio Orrego, M.D.

"Primary care doctors are the gatekeepers of the health care system, and it's crucial that they catch this infection early by asking about risk factors, ordering tests, and referring those who test positive for evaluation and treatment," says Dr. Lok. "And since primary care is a two-way street, patients need to know whether they might be at risk, and volunteer that information to their doctors so they can get help and find out how they can keep from spreading the disease."

Adds Dr. Shehab, "General physicians are being expected to screen for more and more diseases, and our results show we need to help them do that in a way that's both efficient and effective."

The study is one of the first of its kind, based on actual medical records from patients at several primary care sites. Drs. Lok and Shehab have also performed surveys of primary care physicians, and found that many reported they thought they did a good job of assessing patients for their hepatitis C risk and referring them for treatment.

The new study did not examine why a higher percentage of patients weren't tested based on risk factors, or what reasons - such as a patient's age or other health problems - might have kept an infected patient from getting a referral. The study also only reflects patients who had a hepatitis C test, and not those who weren't asked about or didn't offer risk factor information.

"Ideally, early diagnosis can be made if doctors ask about hepatitis C risk factors and patients answer honestly," says Dr. Lok. "We shouldn't wait until patients have symptoms, or until the infection has progressed, as treatment is often more effective if it's begun earlier."

"In addition, there are important potential benefits to the public at large of early diagnosis," Dr. Shehab adds. "These include the fact that hepatitis C patients may change behaviors and therefore reduce the risk of transmission to others, and the possibility that they may modify practices such as alcohol consumption that may alter the disease's progression."

Eighty percent of people infected with hepatitis C, either in the initial acute phase or the long-term chronic phase, have no signs or symptoms. Only blood tests for antibodies against the virus, or for the virus' genetic material, can show for sure that they're infected. Infections can go undetected for years or even decades before symptoms begin, even while the liver is slowly destroyed. In the current study, the percentage of patients whose biopsy showed significant liver scarring was high - at least 10 percent of all those who tested positive for the virus.

As many as 3.9 million people in the United States may have the hepatitis C virus, and an estimated 2.7 million of them have chronic infections, putting them at risk for liver failure.

Both professional societies and federal agencies have developed guidelines to help doctors find and treat infections. But public health authorities know that many infections aren't spotted. There is no vaccine against the virus, and even advanced treatments are only moderately successful in slowing the pace of the chronic disease's progression toward either liver transplant or death.

The stigma attached to some risk factors may play a part. Intravenous drug use, risky sexual practices, cocaine use and tattoos from dirty needles are all common means of transmission. Dr. Lok notes that patients need to volunteer information about these behaviors to their doctors - even if it has been decades since the last time. And doctors need to act on that information.

Meanwhile, other behaviors that don't carry a stigma may still put people at risk of infection: occupational exposures in health care workers, long-term dialysis, or having received a blood transfusion or organ transplant before 1992, when surveillance of the blood supply improved.

Once a person tests positive for hepatitis C, further tests and biopsies to determine the subtype of the virus, whether the infection is active or dormant, and the extent of accumulated impact on the liver, are often needed to help guide treatment. This often leads to specialized treatment by those with advanced training in liver disease. For example, Dr. Lok is leading a major national study of a combination therapy that uses a new form of interferon and an antiviral drug.

The question of why only 57 percent of hepatitis C-infected patients in the study were referred to specialists puzzles Dr. Lok and her colleagues. They plan to look at the question prospectively, to see if race, gender, medical, insurance or other factors are at work. They also hope to explore ways to add screening questions about hepatitis C risk factors to the questionnaires that patients in primary care clinics are often asked to fill out when they arrive, or to find ways to use technology to make that process more efficient.

SOURCE: University of Michigan Health System, via DG Dispatch