Polypharmacy and Medical Intensive Care Unit (MICU) Admission and 10-year All-cause Mortality Risk Among Hospitalized Patients with and Without HIV

Objective: Medical intensive care unit (MICU) admissions have been declining in people with HIV infection (PWH), but frequency of outpatient polypharmacy (prescription of ≥5 chronic medications) has increased. Among those hospitalized, we examined whether outpatient polypharmacy is associated with subsequent 1-year MICU admission or 10-year all-cause mortality, and if the association varies by HIV status.

Design: Retrospective cohort study.

Methods: Using a national electronic health record cohort of Veterans in care, we ascertained outpatient polypharmacy during fiscal year (FY) 2009 and followed patients for 1-year MICU admission and 10-year mortality. We assessed associations of any polypharmacy (yes/no and categorized ≤4, 5-7, 8-9, and ≥10 medications) with 1-year MICU admission and 10-year mortality using logistic and Cox regressions, respectively, adjusted for demographics, HIV status, substance use, and severity of illness.

Results: Among 9898 patients (1811 PWH) hospitalized in FY2010, prior outpatient polypharmacy was common (51%). Within 1 year, 1532 (15%) had a MICU admission and within 10 years, 4585 (46%) died. Polypharmacy was associated with increased odds of 1-year MICU admission, in both unadjusted (odds ratio (OR) 1.36 95% CI: (1.22, 1.52)) and adjusted models, aOR (95% CI) = 1.28 (1.14, 1.43) and with 10-year mortality in unadjusted, hazard ratio (HR) (95% CI) = 1.40 (1.32, 1.48), and adjusted models, HR (95% CI) = 1.26 (1.19, 1.34). Increasing levels of polypharmacy demonstrated a dose-response with both outcomes and by HIV status, with a stronger association among PWH.

Conclusions: Among hospitalized patients, prior outpatient polypharmacy was associated with 1-year MICU admission and 10-year all-cause mortality after adjusting for severity of illness in PWH and PWoH.