Background: Herpes zoster occurs at all CD4 cell counts in HIV-infected adults. It was hypothesized that even in the era of highly active antiretroviral therapy (HAART), zoster risk is higher in HIV-infected than uninfected women.
Methods: Generalized estimating equations modeled self-reported occurrence of zoster between semiannual visits among 1832 HIV-infected and 489 HIV-uninfected women in the Women's Interagency HIV Study followed for up to 7.5 years.
Results: A total of 337 (18.4%) HIV-infected and 7 (1.4%) HIV-uninfected women reported zoster at some time during follow-up. Using HIV-infected women with CD4 >750 cells/microL as the reference category, the odds ratios for reporting zoster since the prior visit were: 1.43 (95% CI 0.86-2.37) for CD4 500-749 cells/microL, 2.07 (95% CI 1.27-3.38) for CD4 350-499 cells/microL, 2.72 (95% CI 1.66-4.46) for CD4 200-349 cells/microL, and 3.16 (95% CI 1.92-5.18) for CD4 <200 cells/microL, compared with 0.11 (95% CI 0.046-0.26) for HIV-uninfected women. In multivariate analyses using visits from all HIV-infected women and only those who initiated HAART, lower CD4 cell count was more strongly associated with zoster incidence than were other clinical indicators.
Conclusions: Herpes zoster is associated with degree of immunosuppression in HIV-infected women, but even women with high CD4 counts are at greater risk of zoster than HIV-uninfected women.