Cost-Effectiveness of Screening for HIV in the Era of Highly Active Antiretroviral Therapy

TLDR

In the HAART era, the costs, benefits, and cost‑effectiveness of HIV screening in health‑care settings had not yet been established. The authors constructed a Markov model to compare the costs, quality of life, and survival of an HIV‑screening program with current practice. The model incorporated symptom‑based case finding, initiation of treatment when CD4 fell below 350 cells/mm³, disease progression defined by CD4 and viral load, and transmission risk based on viral load, status awareness, and counseling efficacy. Screening raised life expectancy by 5.48 days (4.70 QALDs) at an estimated $194 per screened patient, yielding a cost‑effectiveness ratio of $15,078 per QALY; it remained below $50,000 per QALY when unidentified prevalence exceeded 0.05 %, and was $41,736 per QALY when transmission was excluded, with five‑year screening costing $57,138 per QALY but preferable in high‑incidence settings, indicating routine screening is comparable to accepted interventions and should be expanded.

Abstract

The costs, benefits, and cost-effectiveness of screening for human immunodeficiency virus (HIV) in health care settings during the era of highly active antiretroviral therapy (HAART) have not been determined.We developed a Markov model of costs, quality of life, and survival associated with an HIV-screening program as compared with current practice. In both strategies, symptomatic patients were identified through symptom-based case finding. Identified patients started treatment when their CD4 count dropped to 350 cells per cubic millimeter. Disease progression was defined on the basis of CD4 levels and viral load. The likelihood of sexual transmission was based on viral load, knowledge of HIV status, and efficacy of counseling.Given a 1 percent prevalence of unidentified HIV infection, screening increased life expectancy by 5.48 days, or 4.70 quality-adjusted days, at an estimated cost of 194 dollars per screened patient, for a cost-effectiveness ratio of 15,078 dollars per quality-adjusted life-year. Screening cost less than 50,000 dollars per quality-adjusted life-year if the prevalence of unidentified HIV infection exceeded 0.05 percent. Excluding HIV transmission, the cost-effectiveness of screening was 41,736 dollars per quality-adjusted life-year. Screening every five years, as compared with a one-time screening program, cost 57,138 dollars per quality-adjusted life-year, but was more attractive in settings with a high incidence of infection. Our results were sensitive to the efficacy of behavior modification, the benefit of early identification and therapy, and the prevalence and incidence of HIV infection.The cost-effectiveness of routine HIV screening in health care settings, even in relatively low-prevalence populations, is similar to that of commonly accepted interventions, and such programs should be expanded.