Broad Hepatitis C screening of Canadian adults not supported by evidence, task force concludes

Healthy Canadian adults who don't have risk factors for curable, chronic hepatitis C infection don't need to be screened, according to new guidelines for family physicians that come amid treatment cost concerns. 

People can be infected with the hepatitis C virus for 30 years as liver injury worsens.

It's estimated between 6 to 7 per 1,000 adults in Canada or up to 245,000 people have the virus. Of these, some can be potentially be helped by new, costly oral medications called direct-acting antivirals. The antivirals can eradicate the virus in those with symptoms or abnormal liver test results.

The Canadian Task Force on Preventative Health Care recommends against screening for hepatitis C in the general population who don't have symptoms or specific risk factors or behaviours that put them at higher risk of getting infected, said Dr. Roland Grad, chair of the working group that developed the guidelines.

• Hepatitis C cure for under $300 US fuels excitement
• Hepatitis infection not known by most Canadians with the virus

"The reasons for this recommendation include basically we found no evidence to support the benefits of screening in the general adult population," said Grad, a family physician in Montreal and an associate professor of medicine at McGill University. "We found the cost of screening and treatment would have a dramatic impact on our health-care budget because the drugs are extraordinarily expensive."

Overall, there was a theme of uncertainty to the evidence, Grad said. For instance, there's no screening trial that randomly assigned baby boomers to be screened or not and followed them to see who develops cirrhosis or stiffness of the liver.

At the same time, there's already a backlog of patients in Canada who are known to be infected but who don't quality for publicly-funded treatment.

Treatment costs flagged

Expanding screening would label people as chronically infected and add them to queue to be seen by a liver specialist only to be told they also likely don't qualify for treatment, Grad said. The authors estimated the cost of treatment and testing at $1.5 billion.

Instead, the task force calls on family physicians and nurse practitioners to follow 2009 recommendations from the Public Health Agency of Canada and College of Family Physicians to do "case finding" to identify the estimated 44 per cent of people who may be undiagnosed.

The virus can be transmitted through:

• Inadequately sterilized medical equipment.
• Contaminated blood products or unscreened blood, tissues or organs before 1992.
• Injection drug use.
• Less commonly, it can spread through high-risk sexual contact, unsterilized tattoo or piercing equipment and needle-stick injuries.

Dr. Julio Montaner, director of the BC Centre of Excellence in HIV/AIDS, said a study last year by his team and the U.S. Centers for Disease Control and Prevention pointed to exposures from inadequately sterilized reusable syringes and needles, such as those used decades ago in dental freezing and vaccinations.

"We should be offering hepatitis C testing to all high-risk groups — I agree with that — but the baby boomers should be offered it too, because in Canada they have twice the rate of infection of the general population," argued Montaner.

It is considered unethical to screen for a disease when treatment is unavailable or unaffordable, Drs. Genevieve Cadieux and Herveen Sachdeva of the Dalla Lana School of Public Health in Toronto said in a journal commentary.

While gaps in knowledge and barriers to screening are filled, the pair call for current risk-based testing to be optimized.  

"From a health equity and ethical perspective, eligibility for publicly funded treatment should be expanded to all patients with a diagnosis of chronic HCV infection — those at higher risk of complications and those with the greatest ability to benefit from treatment," Cadieux and Sachdeva said.

The good news is that Ontario and British Columbia have announced all people who direct acting antivirals will extend coverage regardless of the severity of their disease, Grad said. How quickly it rolls out remains to be seen.

For its part, the Canadian Liver Foundation takes issue with assumptions it said the task force made, such as that Hepatitis C is a mild disease and how many people are identified or missed by case finding. 

"We now know that Hepatitis C is a progressive disease in everybody. Unless some other cause of death superintervenes, Hepatitis C will cause bad disease in everyone," said Dr. Morris Sherman, chair of the of the Canadian Liver Foundation and a hepatologist in Toronto.

Sherman said there is an obligation to screen broadly and to inform people they have a potentially fatal but curable disease.