title: Stroke incidence and mortality trends in US communities, 1987 to 2011.
abstract: OBJECTIVE
  Prior studies have shown decreases in stroke mortality over time, but data on validated stroke incidence and long-term trends by race are limited.
  
  
  OBJECTIVE
  To study trends in stroke incidence and subsequent mortality among black and white adults in the Atherosclerosis Risk in Communities (ARIC) cohort from 1987 to 2011.
  
  
  METHODS
  Prospective cohort study of 14,357 participants (282,097 person-years) free of stroke at baseline was facilitated in 4 different US communities. Participants were recruited for the purpose of studying all stroke hospitalizations and deaths and for collection of baseline information on cardiovascular risk factors (via interviews and physical examinations) in 1987-1989. Participants were followed up (via examinations, annual phone interviews, active surveillance of discharges from local hospitals, and linkage with the National Death Index) through December 31, 2011. The study physician reviewers adjudicated all possible strokes and classified them as definite or probable ischemic or hemorrhagic events.
  
  
  METHODS
  Trends in rates of first-ever stroke per 10 years of calendar time were estimated using Poisson regression incidence rate ratios (IRRs), with subsequent mortality analyzed using Cox proportional hazards regression models and hazard ratios (HRs) overall and by race, sex, and age divided at 65 years.
  
  
  RESULTS
  Among 1051 (7%) participants with incident stroke, there were 929 with incident ischemic stroke and 140 with incident hemorrhagic stroke (18 participants had both during the study period). Crude incidence rates were 3.73 (95% CI, 3.51-3.96) per 1000 person-years for total stroke, 3.29 (95% CI, 3.08-3.50) per 1000 person-years for ischemic stroke, and 0.49 (95% CI, 0.41-0.57) per 1000 person-years for hemorrhagic stroke. Stroke incidence decreased over time in white and black participants (age-adjusted IRRs per 10-year period, 0.76 [95% CI, 0.66-0.87]; absolute decrease of 0.93 per 1000 person-years overall). The decrease in age-adjusted incidence was evident in participants age 65 years and older (age-adjusted IRR per 10-year period, 0.69 [95% CI, 0.59-0.81]; absolute decrease of 1.35 per 1000 person-years) but not evident in participants younger than 65 years (age-adjusted IRR per 10-year period, 0.97 [95% CI, 0.76-1.25]; absolute decrease of 0.09 per 1000 person-years) (P = .02 for interaction). The decrease in incidence was similar by sex. Of participants with incident stroke, 614 (58%) died through 2011. The mortality rate was higher for hemorrhagic stroke (68%) than for ischemic stroke (57%). Overall, mortality after stroke decreased over time (hazard ratio [HR], 0.80 [95% CI, 0.66-0.98]; absolute decrease of 8.09 per 100 strokes after 10 years [per 10-year period]). The decrease in mortality was mostly accounted for by the decrease at younger than age 65 years (HR, 0.65 [95% CI, 0.46-0.93]; absolute decrease of 14.19 per 100 strokes after 10 years [per 10-year period]), but was similar across race and sex.
  
  
  CONCLUSIONS
  In a multicenter cohort of black and white adults in US communities, stroke incidence and mortality rates decreased from 1987 to 2011. The decreases varied across age groups, but were similar across sex and race, showing that improvements in stroke incidence and outcome continued to 2011.
authors.affiliation: Stanley Steyer School of Health Professions, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel2Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland.
authors.forename: Silvia
authors.initials: S
authors.lastname: Koton
authors.affiliation: Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland.
authors.forename: Andrea L C
authors.initials: AL
authors.lastname: Schneider
authors.affiliation: Department of Epidemiology, University of North Carolina, Chapel Hill.
authors.forename: Wayne D
authors.initials: WD
authors.lastname: Rosamond
authors.affiliation: Division of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson.
authors.forename: Eyal
authors.initials: E
authors.lastname: Shahar
authors.affiliation: Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Sang
authors.affiliation: Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland5Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Rebecca F
authors.initials: RF
authors.lastname: Gottesman
authors.affiliation: Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, Maryland.
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
mesh_terms: D000368:Aged; D044383:Black People / Q000706:statistics & numerical data; D002545:Brain Ischemia / Q000150:complications / Q000208:ethnology / Q000401:mortality*; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002543:Cerebral Hemorrhage / Q000208:ethnology / Q000401:mortality*; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D012307:Risk Factors; D012737:Sex Factors; D020521:Stroke / Q000208:ethnology / Q000401:mortality*; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American