title: Cerebral vasoreactivity is impaired in treated, virally suppressed HIV-infected individuals.
abstract: OBJECTIVE
  To compare cerebral vasoreactivity, a measure of cerebrovascular endothelial function, between treated, virally suppressed HIV-infected individuals and HIV-uninfected controls and to evaluate the effect of HIV-specific factors on cerebral vasoreactivity.
  
  
  METHODS
  Cross-sectional study of 65 antiretroviral therapy-treated, virally suppressed HIV-infected individuals and 28 HIV-uninfected controls. Participants underwent noninvasive assessment of cerebral vasoreactivity using transcranial Doppler ultrasound and inhaled carbon dioxide (CO2). We used mixed effects multivariable linear regression to determine the association of HIV infection and HIV-specific factors with cerebral vasoreactivity.
  
  
  RESULTS
  Mean age was 57.2 years for HIV-infected participants and 53.5 years for HIV-uninfected controls. Most participants (95%) were men. Twenty-six per cent of HIV-infected participants were nonwhite compared to 32% of controls. Among HIV-infected participants, mean CD4 cell count was 596 cells/μl, and mean duration of viral suppression was 7.8 years. Cerebral vasoreactivity in response to hypercapnia (cerebral VRhyper) was lower in HIV-infected individuals compared to uninfected controls (3.23 versus 3.81%, P = 0.010). After adjusting for demographic and vascular risk factors, HIV infection was independently associated with lower cerebral vasoreactivity (-0.86%, 95% CI -1.30 to -0.42%, P < 0.001). We did not find a statistically significant effect of recent or nadir CD4 cell count on cerebral vasoreactivity. There was a trend toward higher cerebral vasoreactivity for each additional year of viral suppression.
  
  
  CONCLUSIONS
  Treated, virally suppressed HIV infection negatively impacted cerebral vasoreactivity even after adjustment for traditional vascular risk factors. These data highlight the potential contribution of cerebrovascular endothelial dysfunction to the elevated risk of stroke observed in HIV-infected individuals.
authors.affiliation: aUniversity of California San Francisco, San Francisco, CaliforniabBrigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Felicia C
authors.initials: FC
authors.lastname: Chow
authors.forename: W John
authors.initials: WJ
authors.lastname: Boscardin
authors.forename: Claire
authors.initials: C
authors.lastname: Mills
authors.forename: Nerissa
authors.initials: N
authors.lastname: Ko
authors.forename: Courtney
authors.initials: C
authors.lastname: Carroll
authors.forename: Richard W
authors.initials: RW
authors.lastname: Price
authors.forename: Steven
authors.initials: S
authors.lastname: Deeks
authors.forename: Farzaneh A
authors.initials: FA
authors.lastname: Sorond
authors.forename: Priscilla Y
authors.initials: PY
authors.lastname: Hsue
mesh_terms: D000328:Adult; D000368:Aged; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D002561:Cerebrovascular Disorders / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D044966:Anti-Retroviral Agents