Incidence and spectrum of severe medical complications among hospitalized HIV-seronegative and HIV-seropositive narcotic drug users

Objectives: To examine differences in the incidence and spectrum of diseases, as well as duration of inpatient stay, between HlV-seronegative and HIV-seropositive narcotic drug users (NDU). Design: Retrospective analysis of 9 years of experience. Data collection by chart review using pre-set criteria for diagnoses. Estimation of hospital admission densities by assuming a dynamic but stable population of 2000 NDU (with a mean HIV-seroprevalence of 25%) throughout the study period. Patients: Comprising 314 HIV-seronegative NDU, 217 HIV-seropositive NDU, and 10 NDU with admissions registered in either group (from a total of 1011 admissions). Results: The overall admission incidence density was 35 and 120 per 1000 person-years among HIV-seronegative NDU and HIV-seropositive NDU, respectively [risk ratio (RR) 3.5, 95% confidence interval (CI) 3.2-3.7]. Compared with seronegative NDU, HIV-seropositve NDU were more frequently admitted for various nonopportunistic infections (RR 7.2, 95% CI 6.1-8.4), including pneumonia (RR 10.9, 95% CI 7.6-16.6), tuberculosis (RR 30.0, 95% CI 3.6-233.8), soft-tissue infections (RR 3.5, 95% CI 1.7-7.2), osteoarticular infections (RR 6.0, 95% CI 1.5-23.9), endocarditis (RR 5.3, 95% CI 1.5-17.9), and various other infections (RR 5.8, 95% CI 3.2-10.5). HIV-seropositive NDU were also more frequently admitted for non-infectious medical complications (RR 2.3, 95% CI 1.8-3.0). Seronegative NDU had a shorter median inpatient stay (2 versus 9 days, P < 0.00001). HIV infection accounted for an estimated excess burden of at least 2700 inpatient care days in 9 years among the 500 local HIV-seropositive NDU. Conclusions: Among NDU, HIV infection adds considerable excess burden in terms of severe complications needing inpatient care.