title: Carotid Intima-Media Thickness Progression in HIV-Infected Adults Occurs Preferentially at the Carotid Bifurcation and Is Predicted by Inflammation.
abstract: BACKGROUND
  Shear stress gradients and inflammation have been causally associated with atherosclerosis development in carotid bifurcation regions. The mechanism underlying higher levels of carotid intima-media thickness observed among HIV-infected individuals remains unknown.
  
  
  RESULTS
  We measured carotid intima-media thickness progression and development of plaque in the common carotid, bifurcation region, and internal carotid artery in 300 HIV-infected persons and 47 controls. The median duration of follow-up was 2.4 years. When all segments were included, the rate of intima-media thickness progression was greater in HIV-infected subjects compared with controls after adjustment for traditional risk factors (0.055 vs. 0.024 mm/year, P=0.016). Rate of progression was also greater in the bifurcation region (0.067 vs. 0.025 mm/year, P=0.042) whereas differences were smaller in the common and internal regions. HIV-infected individuals had a greater incidence of plaque compared with controls in the internal (23% vs. 6.4%, P=0.0037) and bifurcation regions (34% vs. 17%, P=0.014). Among HIV-infected individuals, the rate of progression in the bifurcation region was more rapid compared with the common carotid, internal, or mean intima-media thickness; in contrast, progression rates among controls were similar at all sites. Baseline hsCRP was elevated in HIV-infected persons and was a predictor of progression in the bifurcation region.
  
  
  CONCLUSIONS
  Atherosclerosis progresses preferentially in the carotid bifurcation region in HIV-infected individuals. hsCRP, a marker of inflammation, is elevated in HIV and is associated with progression in the bifurcation region. These data are consistent with a model in which the interplay between hemodynamic shear stresses and HIV-associated inflammation contribute to accelerated atherosclerosis. (J Am Heart Assoc. 2012;1:jah3-e000422 doi: 10.1161/JAHA.111.000422.)
  
  
  BACKGROUND
  URL: http://clinicaltrials.gov. Unique identifier: NCT01519141.
authors.affiliation: Divisions of Cardiology, University of California San Francisco (P.Y.H., A.S., A.F.B., K.M., P.G., S.C.K.).
authors.forename: Priscilla Y
authors.initials: PY
authors.lastname: Hsue
authors.forename: Rebecca
authors.initials: R
authors.lastname: Scherzer
authors.forename: Peter W
authors.initials: PW
authors.lastname: Hunt
authors.forename: Amanda
authors.initials: A
authors.lastname: Schnell
authors.forename: Ann F
authors.initials: AF
authors.lastname: Bolger
authors.forename: S C
authors.initials: SC
authors.lastname: Kalapus
authors.forename: Kristinalisa
authors.initials: K
authors.lastname: Maka
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Martin
authors.forename: Peter
authors.initials: P
authors.lastname: Ganz
authors.forename: Steven G
authors.initials: SG
authors.lastname: Deeks
keywords: AIDS; atherosclerosis; carotid arteries; inflammation