Overestimates of Survival after HAART: Implications for Global Scale-Up Efforts

Background: Monitoring the effectiveness of global antiretroviral therapy scale-up efforts in resource-limited settings is a global health priority, but is complicated by high rates of losses to follow-up after treatment initiation. Determining definitive outcomes of these lost patients, and the effects of losses to follow-up on estimates of survival and risk factors for death after HAART, are key to monitoring the effectiveness of global HAART scale-up efforts. Methodology/Principal Findings: A cohort study comparing clinical outcomes and risk factors for death after HAART initiation as reported before and after tracing of patients lost to follow-up was conducted in Botswana's National Antiretroviral Therapy Program. 410 HIV-infected adults consecutively presenting for HAART were evaluated. The main outcome measures were death or loss to follow-up within the first year after HAART initiation. Of 68 patients initially categorized as lost, over half (58.8%) were confirmed dead after tracing. Patient tracing resulted in reporting of significantly lower survival rates when death was used as the outcome and losses to follow-up were censored [1-year Kaplan Meier survival estimate 0.92 (95% confidence interval, 0.88–0.94 before tracing and 0.83 (95% confidence interval, 0.79–0.86) after tracing, log rank P<0.001]. In addition, a significantly increased risk of death after HAART among men [adjusted hazard ratio 1.74 (95% confidence interval, 1.05–2.87)] would have been missed had patients not been traced [adjusted hazard ratio 1.41 (95% confidence interval, 0.65–3.05)]. Conclusions/Significance: Due to high rates of death among patients lost to follow-up after HAART, survival rates may be inaccurate and important risk factors for death may be missed if patients are not actively traced. Patient tracing and uniform reporting of outcomes after HAART are needed to enable accurate monitoring of global HAART scale-up efforts

Hazard ratios for death before and after tracing after initiation of HAART in the IDCC, Gaborone, Botswana.

<p>N = 410</p>*<p>Adjusted for baseline CD4 count (categorized as above), baseline viral load (dichotomized at 100,000 copies/mL), presence of anemia (categorized as above), and age;</p>†<p>adjusted for age, baseline viral load, male sex, and presence of anemia;</p>Ψ<p>adjusted for baseline CD4 count, age, baseline viral load, and male sex</p><p>HR = hazard ratio; CI = confidence interval</p

Patient outcomes before and after tracing in the Infectious Disease Care Clinic, Gaborone, Botswana.

<p>N = 410</p>*<p>P value is for difference in proportion of patients categorized as lost, dead, or on HAART according to two different methods of follow-up.</p>†<p>Tracing revealed that 6 patients originally categorized as lost were still on HAART in the IDCC but had different medical record numbers and were not included in the pharmacy database.</p

Baseline characteristics of patients prior to initiating HAART in the IDCC, Gaborone, Botswana (N = 410)

<p>IQR  =  inter-quartile range; ARV  =  antiretroviral therapy; HAART  =  highly active antiretroviral therapy</p

Kaplan-Meier curve 52-week survival estimates before and after patient tracing, IDCC, Gaborone, Botswana.

<p>Losses to follow-up are censored. Log rank P <0.001.</p