Article

Adjusting survival estimates by incorporating loss to follow-up in antiretroviral therapy programs in sub-Saharan Africa.

Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA.
The Journal of Infectious Diseases (Impact Factor: 5.85). 10/2012; DOI: 10.1093/infdis/jis635
Source: PubMed

ABSTRACT Background. Measuring the survival of adult patients in antiretroviral therapy (ART) programs is complicated by short observation periods and patients lost-to-follow-up (LTFU). We synthesized data from sub-Saharan Africa (SSA) treatment cohorts to estimate survival over five years after initiating ART.Methods. We used data on retention, mortality and loss to follow-up, extracted from 34 cohorts, including a total of 102,306 adult patients from 18 SSA countries, augmented by 13 SSA studies tracking death rates among adult patients LTFU. We used a Poisson regression model to estimate survival over time, incorporating predicted mortality among LTFU patients.Results. Across studies median CD4 count at ART initiation was 104 cells/mm(3), 65% of patients were female, and median age was 37 years. 1-year and 5-year survival, adjusted for loss to follow-up, were estimated at 0.87 (95% C.I: 0.72-0.94) and 0.70 (0.36-0.86), respectively. The life-years gained by a patient over five years after starting treatment were estimated at 2.1 (1.6-2.3) in the adjusted model, compared to 1.7 (1.1-2.0) if assuming 100% mortality among LTFU patients, or 2.4 (1.7-2.7) assuming 0% mortality among LTFU patients.Conclusions. Accounting for loss to follow-up produces substantial changes in the estimated life-years gained during the first five years on ART.

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Stephane Verguet