Reuters Health Information (2010-06-03): HCV delays CD4 recovery when HIV patients start antiretrovirals
HCV delays CD4 recovery when HIV patients start antiretrovirals
Last Updated: 2010-06-03 16:24:16 -0400 (Reuters Health)
NEW YORK (Reuters Health) - The hepatitis C virus (HCV) slows recovery of CD4 counts when HIV patients start antiretroviral therapy, Canadian researchers report.
What's more, the effect of HCV coinfection on CD4 cell count recovery persists for a long time, they say - and this is true regardless of which antiretroviral regimen is used.
The study "gives an additional reason for treating hepatitis C infection in HIV-HCV coinfected patients as it could potentially improve HIV related outcomes as well as help reduce liver related complications," senior author Dr. Marina Klein from the Royal Victoria Hospital in Montreal told Reuters Health by e-mail.
Liver disease progresses more quickly in patients with HCV/HIV coinfection, but "the impact of HCV on HIV progression has been thought to be negligible," Dr. Klein and her colleagues write in their paper, which appeared online May 14th in AIDS.
The researchers compared CD4 cell counts before and after the initiation of antiretroviral therapy in 236 patients with HCV/HIV coinfection. They did the same in 35 HIV patients with spontaneous clearance of HCV infection (i.e., a positive HCV antibody test and no detectable HCV RNA without having received treatment).
The CD4 decline prior to initiation of antiretroviral therapy was nearly two times greater, and CD4 recovery was nearly seven times slower, in HCV/HIV coinfected patients, Dr. Klein and colleagues report.
Specifically, the mean annual decline in CD4 cell counts prior to antiretroviral therapy was 84 cells/microliter in RNA-positive patients vs 44 cells/microliter in RNA-negative patients (according to regression estimates). The mean annual increase in CD4 counts after starting therapy was 4 vs 26 cells/microliter in RNA-positive vs RNA-negative patients, respectively.
"It has been unclear whether active hepatitis C infection has a negative impact on immune responses in HIV," Dr. Klein said. She noted that ongoing T cell activation due to HCV infection, infection of CD4 cells by HCV, or HCV-induced apoptosis of CD4 cells may all contribute to CD4 suppression.
"Our study did not examine the effect of hepatitis C treatment but it suggests that treatment will be important if full recovery of CD4 cell counts is to occur after HIV treatment is started," Dr. Klein said. She added that HCV treatment can be started before or after antiretroviral therapy.