Three clear messages are emerging from the accumulating outcomes reporting from public‐sector adult ART treatment programmes in poor countries. First, treatment is effective for those accessing ART. Hogan summarised eight programmes from resource‐limited settings,
7 demonstrating a range of survival outcomes at 1 and 2 years on ART, but all showing marked improvements over the anticipated natural history without ART. The comparative median survival in those eligible but not receiving ART is variously reported as 24 months, and less than a year for CD4 counts of less than 200 and less than 50 cells/μl, respectively.
8More recently the ART‐LINC collaboration demonstrated cumulative mortality at 1 year of 6.4% in 2725 patients across 12 cohorts with active follow‐up procedures in place.
9 The city‐wide treatment programme in Lusaka reported a mortality of 16.1/100 person years of ART while rapidly scaling up care to over 16 000 patients.
10 In Malawi, cross‐sectionally across 7000 adult patients who ever started ART, 74% remained alive and in care, while cumulatively 10% were estimated to have died by 1 year.
11 Mortality estimates at longer durations on ART include 16.9% of patients having died by 5 years in a cohort in South Africa,
12 and 24.6% by 5 years in a cohort in Senegal.
13Second, in spite of this massive health gain from the intervention, compared with the richest countries, there is still a higher mortality in the first 6 months of treatment in developing countries. The ART‐LINC study referred to above demonstrated that compared with the ART‐CC cohort collaboration from Europe and North America, patients starting ART in developing countries were at up to 4 times greater risk of dying in the first few months on ART after controlling for available measures of disease advancement at baseline. This corroborates the experience of many individual developing country cohorts who describe around two‐thirds of all deaths on ART occurring in the first few months of treatment.
14,15 It is probable that the burden of co‐morbidities could contribute to the early mortality as evidenced by autopsy studies which show frequent undiagnosed tuberculosis and other bacterial infections.
16 Due to the extreme differences in access to healthcare, it may also be that clinically there are residual differences across regions between patients in the same CD4 count and clinical stage strata.
Third, the evaluation of programme effectiveness is hindered by the patients who are lost to programmes—given the limited resources available, there is a fine balance between enrolling as many patients as possible, and retaining those already in care. The proportion of patients lost to care at various durations of follow‐up often approaches or exceeds the proportion known to have died. Even programmes who attempt to actively trace patients who are lost to follow‐up, may end up under‐reporting the number of deaths. One study of patients lost to follow‐up in Malawi demonstrated that half the patients who had been lost had died, and of those, 58% had died in the 3 months following their last clinic visit.
17 After 5 years of follow‐up in Khayelitsha, the proportion lost to care increased from the 16.9% known to have died to 20.3% or 28.2% depending on whether 365 or 90 days were used as the definition of loss to follow‐up.
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