A series of non-invasive tests can predict which HIV-positive women have an increased risk of liver fibrosis, US investigators report in the March 1st edition of Clinical Infectious Diseases.
More advanced HIV disease was associated with poorer liver function even in the absence of hepatitis co-infection, assessed using the so-called FIB-4 index (ALT levels, AST levels, platelet count, and age).
“The FIB-4 index may be widely applicable for the screening of liver fibrosis in HIV-infected populations,” comment the researchers.
Liver disease is a major cause of illness and death in patients with HIV, especially for individuals co-infected with hepatitis B or hepatitis C.
Monitoring the liver function of patients is therefore an important component of routine HIV care. The “gold standard” test for assessing liver disease is a liver biopsy. However, it requires an operation and it is not routinely performed in patients with any evidence of disease.
A combination of non-invasive tests – the FIB-4 index - has been shown to accurately predict liver fibrosis stage in patients with HIV. Investigators from the HIV Epidemiologic Research (HER) study wanted to see which factors were associated with higher FIB-4 scores and more advanced fibrosis in HIV-positive women.
Their study sample included 1227 women with or at risk of HIV. A total of 217 women were HIV-negative, 196 were hepatitis C-mono-infected, 320 were HIV-mono-infected and 498 were co-infected with HIV and hepatitis C.
The median FIB-4 score (0.60) was lowest for women who were negative for both HIV and hepatitis C.
For women mono-infected with hepatitis C, the median FIB-4 score was 0.82.
FIB-4 scores were higher still for women infected with HIV, and their median FIB-4 score was 0.86. A higher CD4 cell count was associated with a lower score (p < 0.0001), as were higher albumin levels (p = 0.002). There was an association of borderline significance (p = 0.08) between viral load and a higher FIB-4 score.
A total of 72 women were HIV-positive, had never taken antiretroviral therapy, did not use alcohol and were infected with hepatitis B virus. HIV viral load in these women was associated with a significantly higher FIB-4 score (p = 0.03)
The median FIB-4 score for women co-infected with HIV and hepatitis C was 1.30. Once again, a higher CD4 cell count (p < 0.001) was associated with a lower score, and HIV viral load with a higher FIB-4 value (p < 0.001).
“Plasma HIV RNA level was associated with increased FIB-4 in HIV-mono-infected women in the absence of ART [antiretroviral therapy] or alcohol use,” comment the investigators. They believe that this finding “suggests a possible effect of HIV load on liver enzyme elevations and/or hepatic fibrosis.” The investigators note that previous research has shown that HIV therapy that suppresses viral load is associated with less fibrosis in HIV/hepatitis C-co-infected patients.
The researchers call for further research “to determine whether highly effective HIV regimens result in decreased FIB-4 values and reduced hepatic fibrosis.”
Blackard JT et al. HIV mono-infection is associated with FIB-4 – a noninvasive index of liver fibrosis – in women. Clin Infect Dis 52: 764-80, 2011 (click here for the free abstract).