Early and Successful Combination Antiretroviral Therapy Normalizes Survival Time in Patients Coinfected With Human Immunodeficiency Virus and Human T-cell Lymphotrophic Virus Type 1

Abstract

Abstract Background Coinfection with human T-cell lymphotrophic virus type 1 (HTLV-1) is associated with shorter survival for adults and children infected with human immunodeficiency virus (HIV), although the reasons remain a matter of debate. We evaluated the factors associated with survival time in a large cohort of HIV/HTLV-1–coinfected and HIV-monoinfected individuals on combination antiretroviral therapy (cART). Methods In a nested, retrospective case-control study (1:1), we reviewed medical records of people with HIV infection on cART in a referral AIDS center in Salvador, Brazil. We matched 149 patients coinfected with HTLV-1 (cases) by age at HIV diagnosis and sex, to an equal number of HTLV-uninfected persons (controls). Death rates, survival time, baseline and current CD4 cell count, last HIV-1 RNA plasma viral load (pVL), and causes of death were compared between groups. Results The overall mortality rate was 2.1 person-years (76 deaths, 53 among coinfected patients). Survival time for cases (16.7 ± 0.7 years) was significantly shorter than for controls (18.1 ± 0.4 years; P = .001). Among patients with pVL >50 copies/mL, coinfected patients had a shorter survival time (8.4 ± 0.8 years) than monoinfected ones (12.9 ± 1.4 years; P = .02), regardless of pVL magnitude. However, survival time did not differ for HIV-monoinfected (19.0 ± 0.4 years) or coinfected patients (20.2 ± 0.6 years) presenting with pVL <50 copies/mL (P = .5). Deceased coinfected patients had higher initial CD4 count (417 ± 219 cells) than monoinfected ones with the same outcome (177 ± 160 cells; P = .004), while survivors had similar CD4 cell count at baseline, regardless of HTLV status. Conclusions Successful cART is able to normalize survival for coinfected patients and should be introduced for all coinfected patients, regardless of CD4 cell count. HIV/human T-cell lymphotrophic virus type 1 coinfection is believed to decrease survival of coinfected patients. In this case-control study, we demonstrate that successful combination antiretroviral therapy (last HIV viral load <50 copies/mL) is able to improve survival of coinfected patients to levels observed for those monoinfected.