Providers face big challenge: HIV/HCV co-infection
Hepatitis B infection also problematic
Estimates of HIV/hepatitis C co-infection rates in the United States range upwards from 30%, and research shows that HIV patients who are infected with hepatitis C have accelerated progression to cirrhosis.
Although end-stage liver disease is a sobering risk for co-infected patients, typically fewer than 10% of co-infected patients are treated for their hepatitis infection, says Barry S. Zingman, MD, medical director of the AIDS Center and medical director of the HIV/HCV Co-Infection Program at Montefiore Medical Center in the Bronx, NY.
Barriers to treatment include inadequate HIV suppression, lack of HCV knowledge among primary care providers and patients, poor adherence, high rates of substance use and side effects, and inadequate access to expert HCV care.1
Montefiore Medical Center now has 30 months of results from the HIV/HCV co-infection program, showing success with the center's model program for treating dozens of co-infected patients, Zingman says.
"We have treated over 90 people and have 45 people on treatment right now," Zingman says. "Every month we have four to five people coming in and the same number coming off treatment, and our success rate has been remarkable."
With typical treatment, 40% to 50% of co-infected patients who start treatment will stop it because of side effects or lack of interest, Zingman notes. "Our rate of stopping for those reasons is one out of 10," he says. "We have to attribute that success to a dedicated team working closely with primary care physicians, all at the same site where patients know the staff and know they can walk in at any time if they have a problem."
Typically in clinical trials of co-infected subjects, the success rate of HCV treatment is about 40%, Zingman says.
"Our success rate of treatment is more than 50%, so we're meeting and exceeding that rate," Zingman says. "This is especially remarkable because our success rate is not with selected patients in a clinical trial, but with anyone who is referred to us for treatment."
For instance, the Montefiore co-infection program includes 75% Latino patients, 20% African-American, and 3% to 4% non-Hispanic Whites, Zingman says. And despite the national perception that African Americans who are co-infected respond more poorly to HCV treatment, the center's experience has been that African American patients have an identical rate of treatment success as Latinos, Zingman says.
"We need to see if over time that rate continues, but so far, the results have been identical," he says.
Screening for hepatitis B inadequate
Hepatitis B infection among HIV patients also is a significant problem, with about 10% of HIV patients co-infected with HBV worldwide, says Chloe L. Thio, MD, an associate professor at Johns Hopkins University School of Medicine in Baltimore, MD.
In the HIV epidemic's early years no one paid attention to hepatitis co-infections because people were dying of HIV-related illnesses, and hepatitis takes a long time to progress to liver disease, Thio notes. "Then in 1996, the prevalence of liver disease in HIV-infected populations has gone up," she says.
There are two ways that medical providers could improve the health of co-infected patients, and these are routine vaccination for hepatitis B among people at high risk for HIV infection and routine screening, followed by treatment, for both hepatitis B and C among HIV patients, Thio says.
Despite recommendations by the CDC for hepatitis B vaccination among gay men and injection drug users, only a small percentage of these populations are becoming vaccinated, Thio says.
Studies suggest that hepatitis screening also is inadequate.2 Most of the four million Americans who are infected with hepatitis C are unaware they're infected, according to data from the NIH.
"The biggest problem is not testing people for HCV or HBV," Thio says.
For HIV-infected patients, HCV is particularly dangerous because studies have shown that HIV infection accelerates HCV infection, and those at risk are primarily injection drug users, Thio says.
Also, HIV patients who are co-infected with HBV have a greater likelihood of death from liver disease than those who are not co-infected, Thio says.
HIV/HBV co-infection also might lead to lamivudine resistance, since the drug often is used to treat hepatitis B, as well as HIV infection, Thio notes.
"We found that after co-infected patients are treated for four years with lamivudine, they are likely to have resistance," Thio says. "Some HIV patients were put on lamivudine years ago and now they have hepatitis B, which becomes more difficult to treat than HIV."
Co-infected patients develop lamivudine resistance for the treatment of HBV than HBV mono-infected patients, Thio adds.
In recent years, the main treatment for HCV infection is a combination therapy of pegylated interferon and ribavirin, which can succeed in up to 50% of people who are infected with genotype 1 and more people who are infected in genotypes 2 and 3, according to CDC statistics.
In the reality of HIV/HCV co-infection, the success rate is hampered by HIV infection, drug use, alcoholism, poor adherence, and other factors, the experts say.
Even with mono-infected patients, the majority have to be on long-term therapy, Thio says.
HIV/hepatitis co-infection likely will continue to be a problem in the United States, even though the blood supply hasn't been a source of transmission of HCV in more than a decade and the hepatitis B vaccine has been available for years, Thio says. "In the near future, we might even see more people who are co-infected," Thio says. "In gay populations where co-infection is more common, we're seeing more HIV transmission and likely we'll see more co-infection because people are less likely to adhere to prevention measures of hepatitis B and C."
- Zingman BS, Ortiz-Morales H, Freeman K, et al. The Montefiore HIV/HCV co-infection program: 18 month results from an expert multidisciplinary team co-located at an urban HIV primary care clinic. Presented at the Treatment and Management of HIV Infection in the United States Conference, held Sept 15-18, 2005, in Atlanta, GA.
- Huckans MS, Blackwell AD, Harms TA, et al. Integrated hepatitis C virus treatment: addressing comorbid substance use disorders and HIV infection. AIDS. 2005;19(Suppl3):S106-115.