Purpose: To describe the cost of hospitalization and treatment in patients with very advanced disease who tart different regimens based on a protease inhibitor (PI).
Method: An observational retrospective analysis was performed on data from a 48-week randomized, multicenter study. Analysis was based on a subgroup of centers that were geographically defined. Costs of ordinary hospital admissions and of antiretroviral treatment were considered. Incidence of hospitalization and number of days free from hospitalization during the period of observation were calculated. Cost and hospitalization measures were compared among patients receiving three different therapeutic regimens: only PI, PI plus one nucleoside, or PI plus two nucleosides. A multivariate analysis was used to assess cost differences, controlling for variables potentially able to influence outcome.
Results: Overall, among 166 patients starting PI (PI plus two nucleosides, 71;PI plus one nucleoside, 65; only PI, 30), 162 ordinary hospital admissions were observed during about 1 year of follow-up. Monthly rates of admission per person and incidence of first hospitalization on 100 person-months showed a clear inverse relationship with the number of drugs comprising the baseline treatment regimen, with the lower rates for the triple therapy group (0.06 and 3.9, respectively), intermediate values for the dual therapy group (0.10 and 8.1, respectively), and higher rates for the PI monotherapy group (0.15 and 13.7, respectively). The average number of days free from hospitalization per month was 29.5 in the triple therapy group, 28.6 in the dual therapy group, and 27.9 in the monotherapy group. The results of cost analysis showed, despite higher cost of antiretroviral treatment, that global costs were progressively lower using regimens of increasing potency: Compared to PI monotherapy, global cost (costs of antiretroviral treatment and of hospitalizations combined) per month per patient was 31.9% lower for the triple therapy group and 19.3% lower for the dual therapy. Global cost for the triple therapy was 15.7% lower compared to global cost for dual therapy. After adjustment for CD4 count, AIDS status, and Karnofsky score, both hospitalization costs and global costs were significantly lower for triple therapy compared to monotherapy (p =.002 and.039, respectively).
Conclusion: In advanced and nucleoside-experienced patients, PI-containing regimens have a differential impact according to the overall strength of the regimen, with the best effects on both hospitalizations and treatment costs obtained using PI within potent combination regimens.