Modifications of health resource-use in Italy after the introduction of highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV) infection. Pharmaco-economic implications in a population-based setting

Objective: To assess the impact of highly active antiretroviral therapy (HAART) on health resource utilisation (HRU) and to estimate associated direct costs in a population based setting. Design: Retrospective study of all patients in the Institute of Infectious and Tropical Diseases (Brescia, Northern Italy) during a 4 years period related to the prescription of HAART has been performed: from 1997 (before HAART) to 2000 (after substantial period of HAART prescription). Main outcome measures and results: HIV inpatient admissions (IA's) decreased from 506.8/1000 patients (pts) in 1997 to 246.3/ 1000 pts in the year 2000. Day care admissions (DCA's) also decreased from 1658.3/1000 pts to 942/1000 pts, while outpatient consultations (OC's) increased from 2046.9/1000 pts to 2590.6/1000 pts in the same years, respectively. By contrast, a relative increase of IA's and DCA's of patients whose serostatus was HIV-negative or unknown has been found. Cost of antiretroviral therapy increased by 2582 Euro (2272 US $), while cost of HIV care (IA+DCA+OC) decreased by 1546 Euro (1360.4 US $) per patient, resulting in a saving in direct cost equal to 60% of the increase in the expenditure for antiretroviral drugs. Conclusions: Our results demonstrate the shift of HIV care from inpatient to outpatient services that occurred after HAART had been introduced into clinical practice. Despite persisting clinical benefits, an increase in total direct cost for HIV pts has been seen for the first time during the HAART era in the year 2000, probably due to an over-prescription of HAART, according to actual Guideline for antiretroviral therapy use, to pts who were not at risk of clinical progression in the short term. Pharmacoeconomical surveillance of HAART is necessary while a favourable impact on the saving in cost is expected from the new treatment guidelines that suggest a relative delay in starting HAART.