BACKGROUND: Although antiepileptic drugs (AEDs) have a potential for adverse drug reactions in older populations, little is known about their use in relation to Alzheimer's disease (AD) diagnosis.

OBJECTIVES: In this study, we investigated the incidence and prevalence of AED use in relation to AD diagnosis.

METHODS: The MEDALZ-study includes all Finnish persons who received clinically verified AD diagnoses (n = 70,718) during 2005-2011 and a matched comparison cohort without AD (n = 70,718). AD diagnoses were identified from the Special Reimbursement Register. We used the Prescription Register to identify dispensed AEDs. Incident AED users were identified with a one-year washout period 9-10 years before AD diagnosis, and incidence rates per 100 person-years were calculated for each six-month period from nine years before to five years after AD diagnosis. Prevalence was assessed as proportion using AEDs during each six-month time period for incident use.

RESULTS: Persons with AD were more likely to use AEDs during the study period (4.3%) than persons without AD (3.2%). The incidence and prevalence of AED use was higher among persons with AD and increased around the time of AD diagnosis. Epilepsy diagnoses did not explain these differences. Persons with AD were more likely to use older AEDs.

CONCLUSION: Our study highlights the need to balance effective symptom control with the possible risks of treatment.