Prophylaxis for human immunodeficiency virus-related Pneumocystis carinii pneumonia: using simulation modeling to inform clinical guidelines.

Abstract

BACKGROUND:

Human immunodeficiency virus (HIV)-infected patients receiving highly active antiretroviral therapy (HAART) have experienced a dramatic decrease in Pneumocystis carinii pneumonia (PCP), necessitating reassessment of clinical guidelines for prophylaxis.

METHODS:

A simulation model of HIV infection was used to estimate the lifetime costs and quality-adjusted life expectancy (QALE) for alternative CD4 cell count criteria for stopping primary PCP prophylaxis in patients with CD4 cell count increases receiving HAART and alternative agents for second-line PCP prophylaxis in those intolerant of trimethoprim-sulfamethoxazole (TMP/SMX). The target population was a cohort of HIV-infected patients in the United States with initial CD4 cell counts of 350/microL who began PCP prophylaxis after their first measured CD4 lymphocyte count less than 200/microL. Data were from randomized controlled trials and other published literature.

RESULTS:

For patients with CD4 cell count increases during HAART, waiting to stop prophylaxis until the first observed CD4 cell count was greater than 300/microL prevented 9 additional cases per 1000 patients and cost $9400 per quality-adjusted life year (QALY) gained compared with stopping prophylaxis at 200/microL. For patients intolerant of TMP/SMX, using dapsone increased QALE by 2.7 months and cost $4500 per QALY compared with no prophylaxis. Using atovaquone rather than dapsone provided only 3 days of additional QALE and cost more than $1.5 million per QALY.

CONCLUSIONS:

Delaying discontinuation of PCP prophylaxis until the first observed CD4 cell count greater than 300/microL is cost-effective and provides an explicit "PCP prophylaxis stopping criterion." In TMP/SMX-intolerant patients, dapsone is more cost-effective than atovaquone.

• Authors: Sue J Goldie, Jonathan E Kaplan, Elena Losina, Milton C Weinstein, A David Paltiel, George R Seage 3rd, Donald E Craven, April D Kimmel, Hong Zhang, Calvin J Cohen, Kenneth A Freedberg
• Journal: Archives of internal medicine (Arch Intern Med) Vol. 162 Issue 8 Pg. 921-8 (Apr 22 2002) ISSN: 0003-9926 [Print] United States
• PMID: 11966344 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Anti-Infective Agents
• Antiprotozoal Agents
• Naphthoquinones
• Pentamidine
• Dapsone
• Atovaquone

Topics

• AIDS-Related Opportunistic Infections (economics, immunology, prevention & control)
• Anti-Infective Agents (economics, immunology, therapeutic use)
• Antiprotozoal Agents (economics, immunology, therapeutic use)
• Atovaquone
• CD4 Lymphocyte Count (economics)
• Cost-Benefit Analysis (economics)
• Dapsone (economics, immunology, therapeutic use)
• Drug Costs
• Humans
• Life Expectancy
• Models, Theoretical
• Naphthoquinones (economics, immunology, therapeutic use)
• Pentamidine (economics, immunology, therapeutic use)
• Pneumonia, Pneumocystis (economics, immunology, prevention & control)
• Practice Guidelines as Topic (standards)
• Quality-Adjusted Life Years