Variables and Definitions

We extracted sex, date of birth, weight, height, Republic of South Africa Identity Number, and date of joining the AfA program from the form completed by the doctor on registering the patient with AfA.

We extracted longitudinal results for CD4 count and VL, and all medication claims for antiretrovirals and concomitant medicines. We created a list of diabetogenic drugs using a pharmacology reference textbook¹⁷ and a review¹⁸ (see Appendix 1). We categorized patients as exposed to diabetogenic drugs if they submitted claims for a diabetogenic drug on 2 or more occasions.

We defined the ART start date as the date on which antiretroviral drugs were first dispensed in the AfA program. The ART starting regimen was the regimen dispensed on this date. The baseline CD4 count, VL, and weight were the values measured closest to the date of ART initiation, within the 12-month window before the ART start date. The primary exposure variable of interest was the NNRTI component of the first-line antiretroviral regimen.