Quiz Ref ID Several studies have demonstrated that HIV-positive people taking antiretroviral therapy (ART) who have low plasma HIV-1 RNA load have markedly reduced infectiousness for sexual transmission.^1-4 In particular, the HPTN 052 study, conducted primarily in heterosexual serodifferent couples, demonstrated a 96% reduction in HIV transmission risk in HIV-positive adults randomized to early ART initiation compared with the group that deferred treatment.⁴ As a result, World Health Organization guidelines now recommend that ART should be offered to all HIV-positive people, irrespective of CD4 cell count, to reduce risk of transmission.⁵

Objectives: Inversion of the CD4:CD8 ratio (< 1) has been identified as a hallmark of inmmunosenescence and an independent predictor of mortality in the general population. We aimed to assess the association between the CD4:CD8 ratio and markers of age‐associated disease in treated HIV‐infected patients with good immunovirological response.Methods: A cross‐sectional analysis was conducted in 132 HIV‐infected adults on antiretroviral therapy (ART), with plasma HIV RNA < 50 HIV‐1 RNA copies/mL for at least 1 year, CD4 count > 350 cells/μL and age < 65 years. We analysed the associations between the CD4:CD8 ratio and subclinical atherosclerosis [assessed using carotid intima‐media thickness (IMT)], arterial stiffness [assessed using the augmentation index (AIx)], the estimated glomerular filtration rate (eGFR), muscle wasting and sarcopenia [assessed using appendicular lean mass/height² (ALM) measured by dual‐energy X‐ray absorptiometry (DEXA)].Results: CD4:CD8 ratio inversion was associated with higher IMT, lower eGFR and lower ALM (all values P < 0.05), but not with AIx. In multivariate analyses adjusted for age, sex, hypertriglyceridaemia, tobacco use and cumulative ART exposure, inversion of the CD4:CD8 ratio was independently associated with higher IMT [odds ratio (OR) 2.9; 95% confidence interval (CI) 1.2–7.1], arterial stiffness (OR 4.8; 95% CI 1.0–23.5) and lower eGFR (OR 5.2; 95% CI 1.0–64.4), but not sarcopenia (OR 0.7; 95% CI 0.2–2.7). These associations persisted when models were applied to subjects with nadir CD4 counts > 200 cells/μL and those with CD4 counts > 500 cells/μL.Conclusions: The CD4:CD8 ratio in treated HIV‐infected subjects with good immunovirological response is independently associated with markers of age‐associated disease. Hence, it might be a clinically useful predictor of non‐AIDS‐defining conditions.