Impacto de la inmunodepresión basal y su grado de recuperación al año de terapia antirretroviral en sobrevida, complicaciones oportunistas y reacción de recuperación inmune

Abstract

Background: Baseline (BL) CD4 cell count is a major factor in outcome of highly active antiretroviral therapy (HAART); treatment induced immune recovery and viral response can modulate this outcome. Aim: To evaluate the association between baseline CD4 cell count and outcome during the first HAART regimen. Material and methods: Prospective study in 2,050 patients on first HAART with a follow up (f/u) of at least 1 year. All had BL CD4 and viral load (VL) counts which were repeated at least twice a year. Patients were grouped according to BL CD4 (cells/mm 3) in <100 (G1), 100-199 (G2) and ≥200 (G3). Groups were further divided according to immune and virological response at 1 year in CD4 > or < 200 and VL detectable or undetectable (<80 copies/mL). Outcome measures were death, AIDS defining events (ADE) and, as a surrogate marker of immune recovery reaction, herpes zoster (HZ). Results: During the first year of follow up, 113 patients (10.8%) died in G1 (n =1,044), 17 (2.5%) in G2 (n =675) (G1-2 p <0.05) and 9 (2.7%) in G3 (n =331) (G2-3 p NS). One hundred twenty five of 919 (13.6%) patients alive at 1 year had ADE in G1, 55/643 (8.5%) in G2 (p <0.05) and 20/320 (5.2%) in G3 (G2-3 p NS). ADEs with follow up CD4 > vs < 200 were: 25/274 (9.1%) vs 100/643 (15.7%) in G1 (p <0.005); 28/404 (6.9%) vs 27/235 (11.2%) in G2 (p NS) and 18/281 (6.4%) vs 2/41 (4.8%) in G3 respectively (p NS). Detectable VL was an additional risk for ADE only in G1 without CD4 recovery. HZ was seen in 6.6% of G1 vs 4% in G2 (p <0.05) and 4.3% in G3. HZ rate was higher in all groups reaching a follow up CD4 >200 than those who did not, with a statistically significant difference at p <0.05 only in G1 (9.5% vs 5.3%). Conclusions: The occurrence of death and ADE during the first year of HAART was significantly higher in patients with a BL CD4 <100, but no statistically significant difference was observed from BL CD4 >100 upwards. Immune recovery during f/u in the more immunosuppressed group greatly improved the outcome. The group with lowest BL CD4 and greater immune recovery showed the highest rate of immune recovery reaction (Rev Méd Chile 2008; 136: 1503-10).