Mortality of treated HIV-1 positive individuals according to viral subtype in Europe and Canada: collaborative cohort analysis. AIDS
Boulle et al. on behalf of eight European and three Canadian cohorts, aimed at estimating the prognosis by viral subtype in HIV-1-infected individuals from start of antiretroviral therapy (ART) and after viral failure. The authors analyzed 20’784 patients who experienced 1’172 deaths during 104’649 person-years of follow-up for an overall mortality rate of 11.2 per 1000 person-years. Subtype B was most frequent (74%), followed by C (10%), CRF02AG (5%), A (4%), CRF01AE (2.4%), G (1.7%), and D (1.1%). Subtype C was predominant in those from sub-Saharan Africa (SSA) (63%), whereas subtype CRF02_AG was common in those from SSA, and CRF01_AE was predominant in Asian patients. Subtype B included the highest proportion of MSM (67%) and IDU (10%), whereas more than 50% of those with subtypes A, C, D, G and CRF02_AG were female. Crude mortality was greatest for subtype B but after stratification by cohort, region of origin and transmission group the highest mortality hazard ratio (MHR) was for subtype A. There was little difference in adjusted MHR between the other subtypes and in survival after viral failure between subtypes A, B, and C.
In conclusion, patients infected with subtype A may be at a survival disadvantage compared with other subtypes although this may be due to other epidemiological factors rather than subtype per se.