First opportunistic illness after enrollment in IPEC cohort, absolute numbers and incidence rates per 1000 persons-years for 1987–2012 and by calendar period.

Diseases with less than 10 cases reported during the study period are not shown (progressive multifocal leukoencephalopathy n = 8, invasive cervical cancer n = 1, coccidioidomycosis n = 1).aTrend was tested for all illnesses with 40 cases of more during the study period.bIncidence rate ratio between 2009–2012 and 19987–1990 periods.cReference period was 1994–1996 since the IR in previous periods were equal to zero.