CD4:CD8 ratio and CD8 cell count and their prognostic relevance for coronary heart disease events and stroke in antiretroviral treated individuals. JAIDS
Chammartin et al. investigated whether markers of chronic immune activation play a role in the development of myocardial infarction (MI) or stroke among participants from the Swiss HIV Cohort Study receiving antiretroviral therapy (ART).
The present study included all individuals with follow-up between April 2000 and March 2021. Markers for immune activation that were assessed included CD4 and CD8 cell counts, as well as the CD4:CD8 ratio. Their association with MI or stroke was evaluated using multivariable Cox regression, adjusted for cardiovascular risk factors such as dyslipidemia, hypertension, diabetes, smoking, and others.
The study included 15’303 individuals who received ART after April 2000. Of those, 85% were less than 50 years old, 28% were women, 42% were men who have sex with men, and 22% had a CD4 cell count at the treatment start below 200 cells/μL. Diabetes was present in 1.7%, obesity in 4.2%, and 42% reported active smoking. Within a median follow-up of 11 years, 563 individuals developed MI (incidence rate [IR] 3.22 per 1000 person-years), and 275 experienced a stroke (IR 1.57 per 1000 person-years). After adjusting for cardiovascular risk factors, none of the markers of chronic immune activation was associated with the development of MI. In contrast, individuals with a CD8 cell count above 1000 cells/μL were more likely to have a stroke (adjusted hazard ratio 1.61, 95% CI 1.06-2.45).
In summary, the present study found that immune activation might play a role in the development of stroke, but not in coronary heart disease. These findings underline the importance of early treatment initiation and optimal immune restoration.