HIV-positive migrants from sub-Saharan Africa to Switzerland are just as likely as northern Europeans to access HAART and benefit from anti-HIV therapy, according to data published in the October 17th edition of AIDS.
Access to HIV therapy is free in Switzerland through the state’s compulsory medical insurance scheme, and the findings of this study are in contrast to Canadian research reported earlier this week (see link below). This study found that even though free HIV treatment was available, minority groups were significantly less likely to access treatment.
The Swiss HIV cohort has been continuously enrolling HIV-positive individuals aged 16 or over since 1988. For the present study information on new enrollments between 1997 and 2002 was gathered. Migration to Switzerland from sub-Saharan Africa increased significantly during this period and researchers wished to see if there were any differences in the extent to which recent African migrants accessed and benefited from HAART compared to northern Europeans.
At six monthly intervals investigators gathered information on new enrollments to the cohort. Data on age, sex, mode of HIV transmission, HIV viral load, CD4 cell count, and HIV disease stage were gathered for sub-Saharan Africans and compared to information obtained from northern Europeans enrolled during the same period.
Uptake of anti-HIV therapy was measured as the proportion of participants with a CD4 count below 350 cells/mm3 who started HAART.
A total of 11, 872 individuals had been enrolled to the Swiss Cohort by the end of April 2002. The overwhelming majority, 79% were of northern European origin, with 6% from sub-Saharan Africa and 15% from other regions.
The number of sub-Saharan migrants in the Swiss Cohort increased steadily from less than 1% in 1989 to 11.9% in the 1997 – 2001 period (linear trend p
Investigators also found that sub-Saharans were significantly younger than northern Europeans at the time of HIV diagnosis in Switzerland (median age 31.5 years versus 37 years, p3 versus 324 cells/mm3, p=0.002), although similar proportions of patients from the two geographical regions presented with severe immune suppression (CD4 cell count below 200 cells/mm3, 35% versus 31%, p=0.13) and viral loads were comparable (15,000 copies/mL versus 19,000 copies/mL, p=0.0002).
Similar proportions of Africans and northern Europeans started HAART within 30 days of enrollment into the cohort (23% versus 21%) Although Africans were more likely than Europeans to have a CD4 cell count below 350 cells/mm3 (51% versus 43%) at enrollment, similar proportions started therapy during follow-up (85% versus 83%).
Research conducted in the UK found that Africans were more likely to be diagnosed with an AIDS-defining illness or significant immune damage (see link below).The Swiss investigators found that there was a trend for Africans to start therapy at lower CD4 cell counts (median 195 cells/mm3 versus 259 cells/mm3, p=0.07), but they believed that this could be because Africans had suffered a greater degree of immune damage by the time of their arrival in Switzerland.
Investigators found that the rate of progression to an AIDS-defining illness was similar between the two patient populations (p=0.14), with only lower CD4 cell count and higher HIV viral load being predictive of disease progression. There were however differences in the types of AIDS-defining illness which Africans and Europeans developed, with TB (35% of cases) and KS (20% of cases) being the most common illness in Africans compared to PCP (17%), thrush in the throat (17%0 and KS (11%) in Europeans.
Although Europeans were initially found to be at greater risk of death than Africans (p=0.16), when analysis was restricted to individuals who had acquired HIV through heterosexual sex survival was not connected with country of origin (p=0.09). The only factors found to affect the risk of death were age, the presence of an AIDS-defining illness at enrollment, lower CD4 cell count at enrollment, and injecting drug use as HIV risk behaviour.
The investigators conclude “there is no evidence that country of origin…affects uptake of potent antiretroviral therapy or rates of disease progression.” However, given the high incidence of TB amongst patients from Africa they advocated greater efforts to provide TB therapy and prophylaxis to this patient group.
Further information on this website
HAART has not led to earlier testing and treatment of Africans in the UK - news story December 2001
Free treatments not accessed by a third of British Columbians who died of HIV/AIDS - news story October 2003
Staehelin C et al. Migrants from sub-Saharan Africa in the Swiss HIV Cohort Study: access to antiretroviral therapy, disease progression and survival. AIDS 17: 2237 – 2244, 2003.