CD4+ cell count and outcomes among HIV-infected compared with uninfected medical ICU survivors in a national cohort.

Abstract

People with HIV (PWH) with access to antiretroviral therapy (ART) experience excess morbidity and mortality compared with uninfected patients, particularly those with persistent viremia and without CD4+ cell recovery. We compared outcomes for medical intensive care unit (MICU) survivors with unsuppressed (>500 copies/ml) and suppressed (≤500 copies/ml) HIV-1 RNA and HIV-uninfected survivors, adjusting for CD4+ cell count. We studied 4537 PWH [unsuppressed = 38%; suppressed = 62%; 72% Veterans Affairs-based (VA) and 10 531 (64% VA) uninfected Veterans who survived MICU admission after entering the Veterans Aging Cohort Study (VACS) between fiscal years 2001 and 2015. Primary outcomes were all-cause 30-day and 6-month readmission and mortality, adjusted for demographics, CD4+ cell category (≥350 (reference); 200-349; 50-199; <50), comorbidity and prior healthcare utilization using proportional hazards models. We also adjusted for severity of illness using discharge VACS Index (VI) 2.0 among VA-based survivors. In adjusted models, CD4+ categories <350 cells/μl were associated with increased risk for both outcomes up to 6 months, and risk increased with lower CD4+ categories (e.g. 6-month mortality CD4+ 200-349 hazard ratio [HR] = 1.35 [1.12-1.63]; CD4+ <50 HR = 2.14 [1.72-2.66]); unsuppressed status was not associated with outcomes. After adjusting for VI in models stratified by HIV, VI quintiles were strongly associated with both outcomes at both time points. PWH who survive MICU admissions are at increased risk for worse outcomes compared with uninfected, especially those without CD4+ cell recovery. Severity of illness at discharge is the strongest predictor for outcomes regardless of HIV status. Strategies including intensive case management for HIV-specific and general organ dysfunction may improve outcomes for MICU survivors.