Hepatitis C and HIV
HCV and HIV Co-Infection
- • In the United States, an estimated 200,000 people are infected with both HCV and HIV.
- • Studies estimate that as many as 25-30% of HIV positive people in the U.S. are co-infected with HCV and up to 10% of HCV positive people are HIV infected.
- • In urban areas of the U.S., up to 90% of people who acquired HIV infection from injection drug use also have HCV.
- • In New York, 78% of people with HIV who report injecting drug use are also HCV-infected.
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Both HIV and HCV can be transmitted by blood-to-blood contact, unprotected sex, and from a mother to her infant; however, the efficacy of transmission by these routes varies. HCV is 10 times more infectious than HIV by direct blood-to-blood contact. This explains the higher incidence of HCV infection among IDUs. For this reason, and because HCV infection was common in urban areas of the U.S. for decades before HIV was discovered, most HIV/HCV co-infected injection drug users were likely infected with HCV years before HIV.
In addition, studies have found that:
- • HIV is more transmissible than HCV between sexual partners.
- • HIV is more transmissible than HCV from a mother to her infant.
- • There are low rates of transmission to long-term monogamous sexual partners of HCV-infected people.
- • Among people engaging in high-risk sexual activity with multiple partners, the rates of HCV transmission are significantly lower than the rates of HIV transmission.
- • The risk of sexual transmission of HCV appears to be increased when a person also has HIV.
- • The incidence of mother-to-infant HCV transmission increases if the mother is co-infected with HIV, with rates reported as high as 20%.
Effect of HIV on HCV Disease
Most studies indicate that people with HIV/HCV co-infection experience faster progression to cirrhosis and more liver damage than people who are infected with only hepatitis C. Faster progression may be less likely if the individual's HIV disease is well under control. A weakened immune system allows HCV to replicate faster, and higher HCV viral load makes a person more infectious. Co-infected people with less than 200 T-cells are at a much higher risk of developing cirrhosis, liver failure, and liver cancer, also called hepatocellular carcinoma (HCC).
Effect of HCV on HIV disease
It is still unclear if HCV accelerates HIV disease but, in most cases, it does not appear to. Studies of people with hemophilia who are co-infected have shown alarming rates of HIV disease progression, but other co-infected populations do not appear to experience this effect. HCV may affect the course of HIV by increasing the incidence of liver toxicity caused by HAART. People with badly damaged livers may have a hard time breaking down HIV medications, especially protease inhibitors and non-nucleosides. This can lead to less antiviral activity, a higher HIV viral load, a lower T-cell count, and, over time, limited HIV treatment options. As people live longer with HIV, many more HIV deaths are caused by HCV-related end stage liver disease.
Treating co-infected people
- • People considering treatment should consult with healthcare providers well versed in HIV and HCV treatment.
- • Referrals to specialists (such as a gastroenterologist, hepatologist, and/or infectious disease doctor) are an important part of making informed decisions.
- • The treatments for HCV have not been specifically approved by the FDA to treat HCV in HIV-infected people, although they are commonly used in co-infected people.
- • Currently, there are no published studies of the most effective way to treat co-infected people.
Most physicians work to get HIV under control first. With reduced HIV-related disease progression as a result of HAART (Highly Active Anti-Retroviral Therapy), the decision of who should be treated for HCV (and when) is often determined by:
- • the likelihood of beneficial response to treatment
- • the likelihood of adverse reactions to the medications
- • the risk of progression of liver disease
While questions about when to start treatment and which treatment to start first are still unresolved, there is important information that should be considered when making treatment decisions:
- • Many individuals who are co-infected do not respond as well to HCV therapy as people who are infected only with HCV. Factors affecting a person's response to HCV therapy include age, HIV viral load, CD4 count, HCV viral load, HCV genotype, condition of the liver, and alcohol intake.
- • Protease inhibitors and non-nucleosides are processed through the liver. People beginning HIV anti-viral treatment often experience an increase in HCV viral load and liver enzymes. In most cases, this flare-up will go away relatively quickly. Regular bloodwork is particularly important during the first couple of months after starting any antiviral treatment.
- • Ribavirin and Retrovir (AZT) can both cause severe anemia in many people, therefore it may be best to avoid using both drugs at the same time. Combivir and Trizivir also include AZT and should likewise be avoided in combination with ribavirin.
- • Nucleoside analogues can damage mitochondria, which produce energy for cells. Ribavirin is a nucleoside analogue as are AZT, d4T (Zerit), ddI (Videx), ddC (Hivid), 3TC (Epivir) and abacavir (Ziagen). Mitochondrial toxicity may be more likely in people taking ribavirin in addition to other nucleoside analogues.
- • If ribavirin and ddI (Videx) are used together, particular caution is in order! People taking both drugs have a five times greater likelihood of developing mitochondrial toxicity than people taking ribavirin with other nucleoside analogues.
- • Viramune (nevirapine) has been associated with an increased risk of liver damage in people with hepatitis C, although not all co-infected people will experience liver problems from this drug. Signs of liver problems usually begin within three months after initiation of use.
- • Regular liver function tests are important to monitor the impact of treatment, especially the first 2-3 months after starting a new drug therapy.
- • Interferon has been associated with increased irritability, insomnia, and suicidal ideation. Because depression before and while on treatment is common, co-infected people who are considering therapy that includes interferon are strongly encouraged to have a support network in place which includes a mental health professional and /or support group.
- • High doses of interferon can lower T-cells (CD4s), at least temporarily, although the CD4 percentage is not usually affected. Although interferon can benefit people's immune response to hepatitis C, it may be harmful to the immune response of some people with HIV.
All people co-infected with HIV and HCV should be:
- • Seen by physicians knowledgeable about both HIV and HCV
- • Provided with information to maintain liver health
- • Counseled about the impact of alcohol on the progression of liver disease
- • Counseled on ways to reduce the transmission of HIV and HCV
- • Vaccinated against hepatitis A and hepatitis B, if not previously exposed
- • Evaluated for chronic liver disease, including HCV viral load, genotype, LFT's and perhaps a biopsy
- • Considered for HIV and/or HCV antiviral treatment as needed
- • Counseled about drug interactions and side effects of HCV and HIV treatments
