title: Greater Risk of Stroke of Undetermined Etiology in a Contemporary HIV-Infected Cohort Compared with Uninfected Individuals.
abstract: BACKGROUND
  Although ischemic stroke risk is increased among people living with HIV infection, little is known about the epidemiology of ischemic stroke subtypes in contemporary HIV-infected cohorts. We examined the distribution of ischemic stroke subtypes among predominantly treated HIV-infected individuals to determine if and how the distribution differs from that of the general population.
  
  
  METHODS
  We studied 60 HIV-infected and 60 HIV-uninfected adults with a history of first-ever ischemic stroke between 2000 and 2012. Ischemic strokes were classified as 1 of 5 subtypes based on established criteria. We used multinomial logistic regression models to compare the relative frequency of ischemic stroke subtypes by HIV status.
  
  
  RESULTS
  Large artery atherosclerosis (23%) and stroke of undetermined etiology (23%) were the most common stroke subtypes among HIV-infected individuals. The most recent plasma HIV viral load before the stroke event differed by subtype, with a median undetectable viral load for individuals with large artery stroke and stroke of undetermined etiology. Using cardioembolic stroke as the reference subtype, HIV-infected individuals were at higher proportional risk of stroke of undetermined etiology compared with uninfected individuals (relative risk ratio [RRR]: 8.6, 95% confidence interval [CI]: 1.2-63.7, P = .04). Among HIV-infected individuals with virologically suppressed infection, we observed a trend toward a greater proportion of strokes attributable to large artery atherosclerosis (RRR: 6.7, 95% CI: .8-57.9, P = .08).
  
  
  CONCLUSIONS
  HIV-infected individuals may be at greater proportional risk of stroke of undetermined etiology compared with uninfected individuals. Further investigation is warranted to confirm this finding and determine underlying reasons for this greater risk.
authors.affiliation: Department of Neurology, University of California, San Francisco, San Francisco, California. Electronic address: felicia.chow@ucsf.edu.
authors.forename: Felicia C
authors.initials: FC
authors.lastname: Chow
authors.affiliation: Department of Neurology, University of California, San Francisco, San Francisco, California.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Price
authors.affiliation: Department of Medicine (Division of Cardiology), University of California, San Francisco, San Francisco, California.
authors.forename: Priscilla Y
authors.initials: PY
authors.lastname: Hsue
authors.affiliation: Department of Neurology, University of California, San Francisco, San Francisco, California.
authors.forename: Anthony S
authors.initials: AS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000175:diagnosis / Q000453:epidemiology*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D015658:HIV Infections / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors; D012495:San Francisco / Q000453:epidemiology; D020521:Stroke / Q000175:diagnosis / Q000453:epidemiology*; D013997:Time Factors; D019562:Viral Load
keywords: HIV infection; cerebral infarction; cerebrovascular disease; ischemic stroke subtype