Stroke incidence is decreasing in whites but not in blacks: a population-based estimate of temporal trends in stroke incidence from the Greater Cincinnati/Northern Kentucky Stroke Study.
OBJECTIVE
Although other studies (in largely white populations) have found that stroke incidence declined during the 1990s, we previously reported that stroke incidence in our population (18% of which was black) did not change during that decade and that incidence rates in blacks were significantly higher than in whites. We sought to update temporal trends in stroke incidence by adding new data obtained from our large, biracial population in 2005. The objective of this study was to examine temporal trends in stroke incidence and case-fatality within a large biracial population over time by comparing stroke incidence rates from 1993 to 1994, 1999, and 2005.


METHODS
Within the Greater Cincinnati/Northern Kentucky population of 1.3 million, all strokes among area residents were ascertained at all local hospitals during July 1993 to June 19/94 and calendar years 1999 and 2005. A sampling scheme was used to ascertain cases in the out-of-hospital setting. Only first-ever strokes were included in this analysis. Race-specific incidence rates, standardized to the 2000 US Census population, and case-fatality rates were calculated.


RESULTS
The number of physician-confirmed first-ever strokes in patients >or=20 years of age was 1942 in 1993 to 1994, 2041 in 1999, and 1921 in 2005. In all study periods, blacks had higher stroke incidence than whites, and case-fatality rates were similar between races. In contrast to previous study periods, we found a significant decrease in overall stroke incidence in 2005. When stratified by race and stroke subtype, this change was driven by a decrease in ischemic stroke incidence among whites, whereas ischemic stroke incidence in blacks was unchanged. Hemorrhagic stroke incidence was unchanged in both races.


CONCLUSIONS
For the first time, we report a significant decrease in stroke incidence within our population, which is consistent with other reports in the literature. This decrease was found only among whites, which suggests a worsening of the racial disparity in stroke incidence.
Kleindorfer
Dawn O
DO
Department of Neurology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45242, USA. dawn.kleindorfer@uc.edu
Khoury
Jane
J
Moomaw
Charles J
CJ
Alwell
Kathleen
K
Woo
Daniel
D
Flaherty
Matthew L
ML
Khatri
Pooja
P
Adeoye
Opeolu
O
Ferioli
Simona
S
Broderick
Joseph P
JP
Kissela
Brett M
BM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044383:Black People / Q000208:ethnology* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D007629:Kentucky / Q000453:epidemiology / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D009820:Ohio / Q000453:epidemiology / Q000208:ethnology; D011159:Population Surveillance / Q000379:methods; D020521:Stroke / Q000175:diagnosis / Q000453:epidemiology* / Q000208:ethnology*; D013997:Time Factors; D016896:Treatment Outcome; D044465:White People / Q000208:ethnology* / Q000706:statistics & numerical data*; D055815:Young Adult; D001741:Black or African American