Clinical Characterization of Veterans With Alzheimer Disease by Disease Severity in the United States

Abstract

Purpose: We aimed to examine the clinical characteristics of US veterans who underwent neurocognitive test score-based assessments of Alzheimer disease (AD) stage in the Veterans Affairs Healthcare System (VAHS). Methods: Test dates for specific stages of AD were referenced as index dates to study behavioral and psychological symptoms of dementia (BPSD) and other patient characteristics related to utilization/work-up and time to death. Patients: We identified veterans with AD and neurocognitive evaluations using the VAHS Electronic Health Record (EHR). Results: Anxiety and sleep disorders/disturbances were the most documented BPSDs across all AD severity stages. Magnetic resonance imaging, neurology and psychiatry consultations, and neuropsychiatric evaluations were slightly higher in veterans with mild AD than in those at later stages. The overall average time to death from the first AD severity record was 5 years for mild and 4 years for moderate/severe AD. Conclusion: We found differences in clinical symptoms, healthcare utilization, and survival among the mild, moderate, and severe stages of AD. These differences are limited by the low documentation of BPSDs among veterans with test score-based AD stages. These data support the hypothesis that our cohorts represent coherent subgroups of patients with AD based on disease severity.