OBJECTIVE: To estimate the relative health benefits, and cost-effectiveness of initiating antiretroviral therapy (ART) for human immunodeficiency virus (HIV) at higher levels of CD4 count than currently recommended in national clinical guidelines and for earlier diagnosis of HIV through universal testing in high-prevalence populations in the United Kingdom (UK).
METHODS: A lifetime Markov model that included secondary transmission of HIV was developed; disease-severity health states were stratified by CD4 cell count. Cohort characteristics were derived from national surveillance data. Data on treatment efficacy, natural disease history, utility, and transmission were taken from published literature. The cost of HIV clinical management was taken from a UK patient cohort study. The main outcome was the incremental cost per quality-adjusted life-year (QALY) gained. Future costs and health outcomes were discounted at an annual rate of 3.5% and reported in 2012 pounds.
RESULTS: Initiation of ART at or below a CD4 count of 500 cells/µL compared with 350cells/µL (current clinical practice), resulted in an additional 0.21 QALYs and 0.13 life-years per patient and an additional lifetime cost of £8,193, yielding a cost per QALY gained of £39,123. A minor improvement in diagnosis rates resulted in an additional 0.42 QALYs and 0.29 life-years per patient and an additional lifetime cost of £638, yielding a cost per QALY gained of £1,521, suggesting further improvements in diagnosis and treatment rates could result in a likely cost saving scenario.
CONCLUSIONS: Earlier ART initiation is likely to improve health benefits and reduce HIV transmission rates. Cost-effectiveness estimates were lower when societal benefits of reduced transmissions or earlier HIV diagnosis was included. Primary analysis results should be considered conservative because only benefits of avoided secondary HIV transmissions (not further onward transmissions) were included and these societal benefits were discounted.
