Hospitalizations among HIV controllers and persons with medically controlled HIV in the U.S. Military HIV Natural History Study

Introduction: HIV controllers (HICs) experience relatively low-level viraemia and CD4 preservation without antiretroviral therapy (ART), but also immune activation that may predispose to adverse clinical events such as cardiovascular disease and hospitalization. The objective of this study was to characterize the rates and reasons for hospitalization among HICs and persons with medically controlled HIV.

Methods: Subjects with consistently well-controlled HIV were identified in the U.S. Military HIV Natural History Study. ART prescription and HIV-1 RNA data were used to categorize subjects as HICs or medically controlled as defined by ≥ 3 HIV-1 RNA measurements ≤ 2000 or ≤ 400 copies/mL, respectively, representing the majority of measurements spanning ≥ 12 months. Hospitalizations were tallied and assigned diagnostic categories. All-cause hospitalization rates were compared between groups using negative binomial regression.

Results and discussion: Of 3106 subjects followed from 2000 to 2013, 221 were HICs, including 33 elite (1.1%) and 188 viraemic (6.0%) controllers, who contributed 882 person-years (PY) of observation time. An additional 870 subjects with medically controlled HIV contributed 4217 PY. Mean hospitalization rates were 9.4/100 PY among HICs and 8.8/100 PY among medically controlled subjects. Non-AIDS-defining infections were the most common reason for hospitalization (2.95/100 PY and 2.70/100 PY, respectively) and rates of cardiovascular hospitalization were similar in both groups (0.45/100 PY and 0.76/100 PY). There was no difference in hospitalization rate for HICs compared with subjects with medically controlled HIV (adjusted incidence rate ratio 1.15 [95% confidence interval 0.80 to 1.65]).

Conclusions: All-cause and cardiovascular hospitalization rates did not differ between HICs and persons with medically controlled HIV. Non-AIDS defining infections were common in this young, healthy, predominantly male cohort of military personnel and beneficiaries.