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Published on: March 30, 2014
Influence of alternative thresholds for initiating HIV treatment on quality-adjusted life expectancy: a decision
R Scott Braithwaite1, Mark S Roberts, Chung Chou H Chang
1Yale University and Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516, USA. Ronald.Braithwaite@va.gov
Background:
The optimal threshold for initiating HIV treatment is unclear.
Objective:
To compare different thresholds for initiating HIV treatment.
Design:
A validated computer simulation was used to weigh important harms from earlier initiation of antiretroviral therapy (toxicity, side effects, and resistance accumulation) against important benefits (decreased HIV-related mortality).
Data Sources:
Veterans Aging Cohort Study (5742 HIV-infected patients and 11 484 matched uninfected controls) and published reports.
Target Population:
Individuals with newly diagnosed chronic HIV infection and varying viral loads (10,000, 30,000, 100,000, and 300,000 copies/mL) and ages (30, 40, and 50 years).
Time Horizon:
Unlimited.
Perspective:
Societal.
Intervention:
Alternative thresholds for initiating antiretroviral therapy (CD4 counts of 200, 350, and 500 cells/mm3).
Outcome Measures:
Life-years and quality-adjusted life-years (QALYs).
Results Of Base-Case Analysis:
Although the simulation was biased against earlier treatment initiation because it used an upper-bound assumption for therapy-related toxicity, earlier treatment increased life expectancy and QALYs at age 30 years regardless of viral load (life expectancies with CD4 initiation thresholds of 500, 350, and 200 cells/mm3 were 18.2 years, 17.6 years, and 17.2 years, respectively, for a viral load of 10,000 copies/mL and 17.3 years, 15.9 years, and 14.5 years, respectively, for a viral load of 300,000 copies/mL), and increased life expectancies at age 40 years if viral loads were greater than 30 000 copies/mL (life expectancies were 12.5 years, 12.0 years, and 11.4 years, respectively, for a viral load of 300,000 copies/mL).
Results Of Sensitivity Analysis:
Findings favoring early treatment were generally robust.
Limitations:
Results favoring later treatment may not be valid. The findings may not be generalizable to women.
Conclusion:
This simulation suggests that earlier initiation of combination antiretroviral therapy is often favored compared with current recommendations.
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