Comparison of predictors for early and late mortality in adults commencing HIV antiretroviral therapy in Zimbabwe: a retrospective cohort study.

Background: People living with HIV (PLWHIV) commencing antiretroviral therapy (ART) in sub-Saharan Africa experience significant mortality within the first year. Previously, identified risk factors for mortality may be biased towards these patients, as compared to those who experience late mortality.

Aim: To compare risk factors for early and late mortality in PLWHIV commencing ART.

Methods: A retrospective cohort study of ART-naïve patients aged ≥ 18 years from an outpatient HIV clinic in Zimbabwe. Data were collected between January 2010 and January 2019. Predictors for early (≤ 1 year) and late mortality (> 1 year) were determined by multivariable cox proportional hazards analyses, with patients censored at 1 year and landmark analysis after 1 year, respectively.

Results: Three thousand and thirty-nine PLWHIV were included in the analysis. Over a median follow-up of 4.6 years (IQR 2.5-6.9), there was a mortality rate of 8.8%, with 50.4% of deaths occurring within 1 year. Predictors of early mortality included CD4 count < 50 cells/µL (HR 1.84, 95% CI 1.24-2.72, p < 0.01), WHO Stage III (HR 2.05, 95% CI 1.28-3.27, p < 0.01) or IV (HR 2.83, 95% CI 1.67-4.81, p < 0.01), and eGFR < 90 mL/min/1.73 m (HR 2.48, 95% CI 1.56-3.96, p < 0.01). Other than age (p < 0.01), only proteinuria (HR 2.12, 95% CI 1.12-4.01, p = 0.02) and diabetes mellitus (HR 3.51, 95% CI 1.32-9.32, p = 0.01) were associated with increased risk of late mortality.

Conclusions: Traditional markers of mortality risk in patients commencing ART appear to be limited to early mortality. Proteinuria and diabetes are some of the few predictors of late mortality, and should be incorporated into routine screening of patients commencing ART.