death rates and high rates of viral load suppression have been sustained
throughout the seven years of scale-up in a community-based antiretroviral
treatment service in a poor area of Cape
Town, South Africa.
the cumulative probabilities of loss to follow-up (LTFU) and virological
failure increased over time suggesting a decreased capacity to support the long-term
therapy needs of a growing caseload, according to Mweete D. Nglazi and
colleagues in a prospective cohort study reported in the advance online edition
of the Journal of Acquired Immune
5 million people were estimated to be getting antiretroviral treatment in low-
and middle-income countries by the end of 2009, 3 million of whom are in
sub-Saharan Africa with the majority in South Africa.
of the early successes of ART programmes in sub-Saharan Africa
achieving good immunological, virological and clinical responses have been
challenged by reports of high mortality rates and high losses to follow-up.
This may be explained, in part, by patients diagnosed late and already
few studies have reported on the long-term outcomes of large cohorts in
sub-Saharan Africa, in particular looking at
how ever-increasing caseloads affect a programme’s ability to deliver and maintain
quality of care over time.
of antiretroviral treatment depends on a team of health care workers and
counsellors being able to meet often overlapping short- and long-term goals by
delivering treatment effectively.
short-term goals include rapid reduction of death rates by diagnosis and
treatment of co-morbidities, provision of co-trimoxazole prophylaxis and
getting the best clinical and virological responses to ART; long-term goals include
keeping patients on treatment with good adherence and sustained suppression of
authors undertook a prospective cohort study of treatment-naïve patients aged
15 years and over enrolled between September 2002 and September 2008 in a community-based
antiretroviral treatment service in a poor area of Cape Town, South Africa.
Follow-up data ended in September 2009.
September 2008 3162 patients had started ART with a maximum annual enrolment of
783 patients in the 12 month period of 2005-2006. 67% were women and the median
age was 34 years.
baseline CD4 cell counts changed significantly over successive enrolment
periods from 87 cells (interquartile range (IQR): 45-145) in 2002-2004 to 121
cells (IQR:60-178) in 2007-2008. Median follow-up was 2.4 years (IQR: 1.2-3.8).
of patients to peer counsellors increased four-fold from 2002-2004 to 2007-2008;
and doctor to patient ratios increased by close to 50% from 1:202 in 2002-2004
to 1:395 in 2007-2008.
six years the cumulative probability of death and loss to follow-up was 37.4%,
comparable to another programme in Cape
of over 60% of patients on treatment and in care after six years is a success,
note the authors. However, with each successive year of enrolment the risk of
being lost to the programme increased, raising concerns about the programme’s
ability to maintain an acceptable standard of care.
authors chose to look at the different losses separately as well as early and
late virological responses to antiretroviral treatment to further understand
this trend and how it affected quality of care.
one year mortality rate of 7.9% in this cohort, with many at an advanced stage
of illness, is very low for sub-Saharan Africa
where rates vary between 8% and 26%. The authors stress that even as caseloads
increased low mortality rates in the first year of treatment did not change
viral suppression of <400 copies/mL at 16 weeks in 93% or more of patients also
did not vary over time.
the proportion of those with CD4 cell counts <200 cells/mm³, a subset recognised as having an ongoing high risk
for early mortality, was looked at. From
90% at baseline, this proportion decreased to approximately 20-30% after 48
weeks on antiretroviral treatment and did not vary significantly with
successive years of starting ART.
authors note that these results show that the initial care and treatment
support in the first months on ART was maintained regardless of an increasing
authors note that one of the primary challenges after the first year of ART is
to keep patients on treatment and in care.
the cumulative probability of being lost to follow up after six years was 29.1%
not dissimilar to another programme in Cape Town, the authors found that as
elsewhere this proportion increased significantly with each successive year of
may be explained, the authors note, by an increasing caseload which brings with
it increasing clinic waiting times, shorter consultations, reduced
opportunities for counselling and adherence support as well as human resources
further overstretched for patient tracing following missed appointments.
implication that increasing clinic caseloads led to decreasing treatment
support over time was supported by the rise of an increasing risk of
virological failure along with the increasing rates of LTFU.
six years the probability of virological failure in the whole cohort was 23.1%,
many of whom had drug resistant mutations. An increase in drug resistance leads
to increased switching to protease-inhibitor second-line regimens. Regimens
that are not only considerably more expensive but after which there are few if
any other options.
authors note that the South African population is highly mobile making
long-term care especially difficult. They suggest more efficient referral and
patient tracking systems are needed to provide quality uninterrupted care.
of the study include very complete data from a cohort of over 3000 with one of
the longest follow-up periods in the context of a public sector ART programme
in sub-Saharan Africa.
include, note the authors, an analysis of many end-points raising the
possibility of false-positive findings.
add that while increasing caseloads are suggestive of increased LTFU and
virological failure over time they found no causal association.
authors conclude that “successful early outcomes were sustained between
sequential calendar years during seven years of scale-up. In contrast, the
increasing cumulative probabilities of LTFU or virological failure may reflect
decreasing capacity to adequately support patients during long-term therapy as
clinic caseload increased.”