Older patients on ART in West Africa have higher risk of death

Carole Leach-Lemens
Published: 27 July 2009

Patients over the age of 50 on antiretroviral treatment in West Africa are at increased risk for death compared to younger age groups, Didier Koumani Ekouevi presenting on behalf of A Lokossoue and colleagues reported in a study presented at the 5th IAS Conference on Pathogenesis, Treatment and Prevention in Cape Town, South Africa.

It is thought that older people (≥ 50 years of age) have poorer immune reconstitution on antiretroviral therapy and a more rapid clinical progression in spite of a better virological response when compared with those younger. Data are scarce for those over the age of 50 and on ART. Average life expectancy in Nigeria and Ivory Coast (Côte d’Ivoire) is 47 and 48 respectively.

The National Institutes for Health-funded international epidemiological database to evaluate AIDS (leDEA) comprises twelve regions of which West Africa is one. It constitutes a unique collaboration among cohorts in five West African countries, Benin, Ivory Coast, Gambia, Mali and Senegal to better understand the prognosis and outcome of people (adults, pregnant women and children) infected with HIV.

Immune response at 6 months and mortality at twelve months according to age at the start of antiretroviral treatment were studied in twelve prospective cohorts of HIV-infected adults from leDEA West Africa.

Those ≥ 16 years of age were included; baseline data were recorded at the start of antiretroviral treatment. Endpoints were immunological failure described as an increase in CD4 count of less than 50 cells/mm³ six months after start of antiretroviral treatment, or death. The primary variable of interest was those aged fifty or over.

A total of 16,854 patients were enrolled at the participating sites from 1997 to 2008. Median age at the start of antiretroviral treatment was 37 and the median CD4 cell count 133 cells/mm³. 11.8% of patients were aged fifty or more with a median CD4 cell count at the start of treatment similar to other age groups. 2042 (26.1%) out of 7833 of patients with CD4 counts available had immunological failure after six months on ART.

While age was not associated with immunological failure there was an association between being aged 50 and above and death (hazard ratio = 1.42 [1.01-1.73]).

Twelve percent of HIV-positive adults began ART at age 50 or over of whom 58% were male. The authors noted that a poorer immunological response was seen in HIV-positive patients aged 45 years and over (22%). Limitations include no data on age-related co-morbidities, viral load or adherence. The authors suggest that low output from the thymus gland may explain the results.

The authors propose that in populations in sub-Saharan Africa aged 45 and over viral load monitoring can avoid misdiagnosis of treatment failure. Beginning ART at a higher CD4 count as well as monitoring for diabetes and high blood pressure will help address the needs of this population.

The authors conclude “the management of patients ≥50 years needs special attention in Africa. The documentation of co-morbidities is necessary to understand the prognosis differences by age group as well as further research on ART drug regimens and strategies suitable to this population in resource-limited settings”.

Reference:

Lokossoue A et al. Poor immunological response and high mortality in HIV-infected patients older than 50 years receiving antiretroviral treatment in West Africa: the leDEA West Africa collaboration, Fifth IAS Conference on Pathogenesis, Treatment and Prevention, Cape Town, South Africa, abstract 3812, July 2009.