Cognitive function and incidence of stroke in older Mexican Americans.
BACKGROUND
Given the high prevalence of cognitive impairment in older Mexican Americans and limited longitudinal research examining cognitive function in this ethnic group, we conducted a study examining whether cognitive impairment is a risk factor for new onset of stroke among older Mexican Americans.


METHODS
We performed a prospective cohort study of 2682 Mexican Americans aged 65 years and older living in the southwestern United States. For subjects with no prior history of stroke and who completed the Mini-Mental State Examination (MMSE) at baseline, stroke incidence was assessed after 2, 5, and 7 years of follow-up.


RESULTS
In Cox proportional regression models, MMSE score at baseline predicted risk of incident stroke over a 7-year follow-up period. For the unadjusted model, subjects with an MMSE score of 21 or higher were half as likely to report stroke at follow-up (hazard ratio [HR], 0.49; 95% confidence interval [CI], 0.35-0.69; p <.001) compared with those with a score of less than 21. We found similar results after controlling for relevant risk factors for stroke including age, gender, smoking status, education, body mass index, diabetes, heart attack, systolic blood pressure, and depressive symptoms (HR, 0.54; 95% CI, 0.38-0.77; p =.001). Additionally, each 1-point increase in MMSE score was associated with a 5% reduction in risk (HR, 0.95; 95% CI, 0.92-0.99; p =.01).


CONCLUSIONS
Increasing MMSE score is associated with a decreasing incidence of stroke in older Mexican Americans. This study highlights the need for a more aggressive focus on identifying and addressing cognitive decline in the Mexican American population.
Ostir
Glenn V
GV
Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas 77555, USA. gostir@utmb.edu
Raji
Mukaila A
MA
Ottenbacher
Kenneth J
KJ
Markides
Kyriakos S
KS
Goodwin
James S
JS
D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D017058:Mexican Americans; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology*; D014481:United States / Q000453:epidemiology