Medication prescriptions among patients with mild cognitive impairment and Alzheimer's disease: A large nationwide electronic health record cohort study

Background Cholinesterase inhibitors (ChE-Is), including donepezil, rivastigmine, and galantamine, and the N-methyl-D-aspartate receptor antagonist, memantine, are prescribed to decrease cognitive impairment symptoms. Objective This study examined prescriptions among patients with mild cognitive impairment (MCI) and/or Alzheimer's disease (AD) in the US by age, sex, and race/ethnicity. Methods This retrospective cohort study used Optum's de-identified Market Clarity Data containing electronic health records and insurance claims from January 2017 to September 2021. International Classification of Diseases, Ninth and Tenth Revisions diagnosis codes identified MCI and AD cases. Drug prescriptions were identified before, on, or after the date of first diagnosis. Cases were required to have ≥12 months of database enrolment prior to first diagnosis. Descriptive statistics were stratified by demographic groups. Results During the study period, 197,346 MCI and 144,321 AD cases were identified. Prescriptions were highest in patients with MCI aged 75–84 years before and after diagnosis for ChE-Is (8.1%, 20.4%) and memantine (2.6%, 7.8%) and among patients with AD aged 65–74 years for ChE-Is (25.0%, 38.7%) and memantine (11.2%, 22.1%). After AD diagnosis, the ChE-I prescriptions ranged from 31.3% of African American patients to 34.1% of Asian patients, and from 13.7% of African American patients to 18.5% of Hispanic patients for memantine. Conclusions ChE-I and memantine prescriptions generally increased to a certain age and were similar across sex and race/ethnicity groups. This information helps understand current prescriptions and how best to optimize in all demographic groups.