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

Arch Intern Med. 2002 Apr 22;162(8):921-8. doi: 10.1001/archinte.162.8.921.


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.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

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


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