Socio-economic- and sex-related disparities in rates of hospital admission among patients with HIV infection in Ontario: a population-based study

BACKGROUND Among people living with HIV infection in the era of combination antiretroviral therapy (cART), admission to hospital may indicate inadequate community-based care. As such, population-based assessments of the utilization of inpatient services represent a necessary component of evaluating the quality of HIV-related care. METHODS We used a validated algorithm to search Ontario's administrative health care databases for all persons living with HIV infection aged 18 years or older between 1992/93 and 2008/09. We then conducted a population-based study using time-series and longitudinal analyses to first quantify the immediate effect of cART on hospital admission rates and then analyze recent trends (for 2002/03 to 2008/09) in rates of total and HIV-related admissions. RESULTS The introduction of cART in 1996/97 was associated with more pronounced reductions in the rate of hospital admissions among men than among women (for total admissions, -89.9 v. -60.5 per 1000 persons living with HIV infection, p = 0.003; for HIV-related admissions, -56.9 v. -36.3 per 1000 persons living with HIV infection, p < 0.001). Between 2002/03 and 2008/09, higher rates of total hospital admissions were associated with female sex (adjusted relative rate [RR] 1.15, 95% confidence interval [CI] 1.05-1.27) and low socio-economic status (adjusted RR 1.21, 95% CI 1.14-1.29). Higher rates of HIV-related hospital admission were associated with low socio-economic status (adjusted RR 1.30, 95% CI 1.17-1.45). Recent immigrants had lower rates of both total admissions (adjusted RR 0.70, 95% CI 0.61-0.80) and HIV-related admissions (adjusted RR 0.77, 95% CI 0.61-0.96). INTERPRETATION We observed important socio-economic- and sex-related disparities in rates of hospital admission among people with HIV living in Ontario, Canada.