Objective: To assess the cost-effectiveness of cotrimoxazole prophylaxis in HIV-infected children in Zambia, as implementation at the local health centre level has yet to be undertaken in many resource-limited countries despite recommendations in recent updated World Health Organization (WHO) guidelines.
Design: A probabilistic decision analytical model of HIV/AIDS progression in children based on the CD4 cell percentage (CD4%) was populated with data from the placebo-controlled Children with HIV Antibiotic Prophylaxis trial that had reported a 43% reduction in mortality with cotrimoxazole prophylaxis in HIV-infected children aged 1–14 years.
Methods: Unit costs (US$ in 2006) were measured at University Teaching Hospital, Lusaka. Cost-effectiveness expressed as cost per life-year saved, cost per quality adjusted life-year (QALY) saved, cost per disability adjusted life-year (DALY) averted was calculated across a number of different scenarios at tertiary and primary healthcare centres.
Results: Cotrimoxazole prophylaxis was associated with incremental cost-effectiveness ratios (ICERs) of US$72 per life-year saved, US$94 per QALY saved and US$53 per DALY averted, i.e. substantially less than a cost-effectiveness threshold of US$1019 per outcome (gross domestic product per capita, Zambia 2006). ICERs of US$5 or less per outcome demonstrate that cotrimoxazole prophylaxis is even more cost-effective at the local healthcare level. The intervention remained cost-effective in all sensitivity analyses including routine haematological and CD4% monitoring, varying starting age, AIDS status, cotrimoxazole formulation, efficacy duration and discount rates.
Conclusion: Cotrimoxazole prophylaxis in HIV-infected children is an inexpensive low technology intervention that is highly cost-effective in Zambia, strongly supporting the adoption of WHO guidelines into essential healthcare packages in low-income countries.
From the aNational Centre for Pharmacoeconomics, Department of Pharmacology and Therapeutics, Trinity College, Dublin, Ireland
bCentre for Health Economics, University of York, UK
cMinistry of Health, Lusaka, Zambia
dMedical Research Council Clinical Trials Unit, London, UK
eUniversity Teaching Hospital, Lusaka, Zambia.
Received 8 June, 2007
Revised 16 October, 2007
Accepted 24 October, 2007
Correspondence to Máirín Ryan, National Centre for Pharmacoeconomics, Trinity Health Sciences, St James's Hospital, Dublin 8, Ireland. Tel: +353 87 2224136; fax: +353 1 4730596; e-mail: email@example.com