BWLWH in STEP-AD compared to E-TAU had significantly higher ART adherence (estimate = 9.36 p = 0.045) and lower likelihood of being clinically diagnosed with PTSD (OR = .07, estimate = − 2.66, p = 0.03) as well as borderline significance on higher CD4 count (estimate = 161.26, p = 0.05). This evidence concerns the gene CD4 and post-traumatic stress disorder.