Study Population

Data from CASCADE in EuroCoord (www.EuroCoord.net) 2013 data update were used for this analysis.¹⁵ Briefly, CASCADE is a cohort collaboration of 29 cohorts of individuals with well-estimated dates of HIV seroconversion from Europe (94%), Australia (2%), Canada (0.5%), and Sub-Saharan Africa (3%). Date of seroconversion is estimated as the midpoint between the last negative and first positive HIV antibody test results with a maximum of 3 years between the test dates (85%), laboratory evidence of acute seroconversion (real-time polymerase chain reaction positivity of incomplete Western blot) (13%), the date of seroconversion illness with a negative and positive test no more than 3 years apart (2%), or by a probability distribution to determine the most likely date of transmission for men with hemophilia infected with HIV after transfusion with clotting factor concentrates (<1% of the sample).

All cohorts contributing to CASCADE received ethical approval from their individual ethics review boards.

Adults (≥16 years old) seroconverting in the cART era (post 1995) were included provided they had at least 1 HIV-RNA measurement between 4 and 12 months after seroconversion. Two Sub-Saharan African cohorts were excluded from this analysis as their CD4 cell count and cART initiation patterns are different from those in industrialized country cohorts.¹⁶