J Clin Neurol.  2015 Jul;11(3):252-261. 10.3988/jcn.2015.11.3.252.

Prevalence and Incidence of Epilepsy in an Elderly and Low-Income Population in the United States

• Tang DH
• Malone DC
• Warholak T
• Chong J
• Armstrong
• Slack MK
• Hsu CH
• Labiner DM

• KMID: 1894562
• DOI: http://doi.org/10.3988/jcn.2015.11.3.252

Abstract

BACKGROUND AND PURPOSE
The purpose of this study was to estimate the incidence and prevalence of epilepsy among an elderly and poor population in the United States.
METHODS
Arizona Medicaid claims data from January 1, 2008 to December 31, 2010 were used for this analysis. Subjects who were aged > or =65 years and were continuously enrolled in any Arizona Medicaid health plans (eligible to patients with low income) for > or =12 months between January 1, 2008 and December 31, 2009 were considered eligible for inclusion in the study cohort. In addition to meeting the aforementioned criteria, incident and prevalent cases must have had epilepsy-related healthcare claims. Furthermore, incident cases were required to have a 1-year "clean" period immediately preceding the index date. Negative binomial and logistic regression models were used to assess the factors associated with epilepsy incidence and prevalence.
RESULTS
The estimated epilepsy incidence and prevalence for this population in 2009 were 7.9 and 19.3 per 1,000 person-years, respectively. The incidence and prevalence rates were significantly higher for patients with comorbid conditions that were potential risk factors for epilepsy and were of younger age than for their non-comorbid and older counterparts (p<0.05). The prevalence rates were significantly higher for non-Hispanic Blacks and male beneficiaries than for non-Hispanic Whites and female beneficiaries, respectively (p<0.05).
CONCLUSIONS
This patient population had higher epilepsy incidence and prevalence compared with the general US population. These differences may be at least in part attributable to their low socioeconomic status.

Keyword

epilepsy; incidence; prevalence; poverty; elderly

MeSH Terms

African Continental Ancestry Group
Aged*
Arizona
Cohort Studies
Delivery of Health Care
Epilepsy*
Female
Humans
Incidence*
Logistic Models
Male
Medicaid
Poverty*
Prevalence*
Risk Factors
Social Class
United States*

Figure

• 

  Fig. 1 Flowchart for identifying incident and prevalent epilepsy cases.

• 

  Fig. 2 Flowchart for obtaining final study cohort.

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