New-onset epilepsy risk factors in older veterans.
OBJECTIVE
To identify risk factors for new-onset geriatric epilepsy that may trigger clinicians to consider a differential diagnosis of epilepsy at symptom onset.


METHODS
Retrospective cohort study.


METHODS
National Veterans Affairs (VA) databases.


METHODS
Veterans aged 66 and older in fiscal year 2000 (FY00) who received VA care in FY99 and FY00. Individuals with new-onset epilepsy based on a validated algorithm constituted the epilepsy cohort (n=1,843), and individuals without epilepsy constituted the geriatric cohort (n=1,023,376).


METHODS
Age, sex, and race were derived from VA databases. Clinical conditions associated with new-onset geriatric epilepsy (e.g., cerebrovascular disease, dementia, brain tumor) and stroke risk-factors (e.g., hypertension, diabetes mellitus, cardiovascular disease) were identified using validated International Classification of Diseases, Ninth Revision, Clinical Modification, codes before epilepsy onset (epilepsy cohort) and in FY00 (geriatric cohort).


RESULTS
Multivariable logistic regression analysis indicated that patients with cerebrovascular disease (odds ratio (OR)=3.50, 95% confidence interval (CI)=3.13-3.91), cerebrovascular disease and dementia (OR=4.14, 95% CI=3.46-4.96), brain tumor (OR=2.14, 95% CI=1.46-3.13), head injury (OR=2.11, 95% CI=1.41-3.14), and other central nervous system (CNS) conditions (OR=1.57, 95% CI=1.32-1.88) were more likely to experience new-onset epilepsy. Statin prescription (OR=0.64, 95% CI=0.56-0.73), older age (> or =85 vs 66-74, OR=0.66, 95% CI=0.50-0.87), obesity (OR=0.74, 95% CI=0.62-0.87), and hypercholesterolemia (OR=0.87, 95% CI=0.76-0.98) were associated with a lower likelihood of epilepsy.


CONCLUSIONS
These data suggest greater epilepsy risk for older individuals with CNS insult and an additive effect of cerebrovascular disease and dementia. The statin finding requires further exploration but points to a possible target for prevention of geriatric epilepsy.
Pugh
Mary Jo V
MJ
Department of Veterans Affairs, Veterans Evidence-Based Research Dissemination Implementation Research Center, San Antonio, Texas 78229, USA. PughM@uthscsa.edu
Knoefel
Janice E
JE
Mortensen
Eric M
EM
Amuan
Megan E
ME
Berlowitz
Dan R
DR
Van Cott
Anne C
AC
D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001932:Brain Neoplasms / Q000150:complications; D002561:Cerebrovascular Disorders / Q000150:complications; D015331:Cohort Studies; D006259:Craniocerebral Trauma / Q000150:complications; D003704:Dementia / Q000150:complications; D004827:Epilepsy / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014728:Veterans