Background. Both human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) may increase cardiovascular disease (CVD) risk. Vascular function assessments can be used to study CVD pathogenesis. We compared the effect of immediate versus deferred ART initiation at CD4 counts >500 cells/mm3 on small arterial elasticity (SAE) and large artery elasticity (LAE). Methods. Radial artery blood pressure waveforms were recorded noninvasively. Small arterial elasticity and LAE were derived from analysis of the diastolic pulse waveform. Randomized treatment groups were compared with linear models at each visit and longitudinal mixed models. Results. Study visits involved 332 participants in 8 countries: mean (standard deviation [SD]) age 35 (10), 70% male, 66% nonwhite, 30% smokers, and median CD4 count 625 cells/mm3 and 10-year Framingham risk score for CVD 1.7%. Mean (SD) SAE and LAE values at baseline were 7.3 (2.9) mL/mmHg × 100 and 16.6 (4.1) mL/mmHg × 10, respectively. Median time on ART was 47 and 12 months in the immediate and deferred ART groups, respectively. The treatment groups did not demonstrate significant within- person changes in SAE or LAE during the follow-up period, and there was no difference in mean change from baseline between treatment groups. The lack of significant differences persisted after adjustment, when restricted to early or late changes, after censoring participants in deferred group who started ART, and among subgroups defined by CVD and HIV risk factors. Conclusions. Among a diverse global population of HIV-positive persons with high CD4 counts, these randomized data suggest that ART treatment does not have a substantial influence on vascular function among younger HIV-positive individuals with preserved immunity.
Bibliographical noteFunding Information:
Financial support. The START study (NCT00867048) and the START Arterial Elasticity Substudy (NCT01776151) are registered at clinicaltrials. gov. The START study is primarily funded by the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH) under Award Number UM1-AI068641, the Department of Bioethics at the NIH Clinical Center and 5 NIH institutes: the National Cancer Institute, the National Heart, Lung, and Blood Institute (NHLBI), the National Institute of Mental Health, the National Institute of Neurological Disorders and Stroke, and the National Institute of Arthritis and Musculoskeletal Disorders. Additional support for Arterial Elasticity Substudy data collection was provided by the NHLBI/NIH. Additional financial support for START was also provided by the French Agence Nationale de Recherches sur le SIDA et les Hépatites Virales, the German Ministry of Education and Research, the European AIDS Treatment Network, the Australian National Health and Medical Research Council, and the UK Medical Research Council and National Institute for Heath Research. Six pharmaceutical companies
- Antiretroviral therapy
- Arterial elasticity
- Cardiovascular disease
- HIV infection
- Vascular dysfunction