J Am Geriatr Soc. 2026 Aug 6. doi: 10.1111/jgs.70630. Online ahead of print.
ABSTRACT
BACKGROUND: People with Alzheimer’s disease and related dementias (ADRD) are at increased risk of motor vehicle crash (MVC) due to cognitive decline, which often begins years before diagnosis. MVC could serve as an indicator of ADRD-related cognitive impairment and facilitate earlier diagnosis.
METHODS: We conducted a matched cohort study of Medicare beneficiaries in New Jersey aged ≥ 69 years with incident ADRD diagnoses from 2010 to 2017 compared to individuals without ADRD and with four other medical conditions: acute myocardial infarction (AMI), asthma, chronic obstructive pulmonary disease (COPD), and diabetes. Comparison groups were sampled with replacement and matched on sex, age, and calendar quarter of diagnosis or claim (for the non-ADRD group). Crash prevalence at 6 months and 1, 2, and 3 years before diagnosis was compared using chi-square tests, and the monthly prevalence was plotted to examine longitudinal trends in crashes.
RESULTS: We identified 43,115 eligible individuals with incident ADRD diagnosis from 2010 to 2017. MVC crash prevalence was higher in the ADRD group than in non-ADRD and negative control groups at all measured pre-diagnosis time points: 6 months (2.99% vs. 2.31%-2.53%), 1 year (5.26% vs. 4.18%-4.65%), 2 years (9.52% vs. 7.88%-8.67%), and 3 years (13.64% vs. 11.29%-12.37%). The ADRD group was more likely to have multiple crashes in the pre-diagnosis period, but multiple events were rare overall (< 3%). Differences were statistically significant but represented small changes in prevalence. Crash prevalence did not reveal a clear signal of cognitive decline in the years leading up to the index diagnosis.
CONCLUSIONS: Older adults with ADRD had slightly higher prevalence of MVC in the 3 years before diagnosis than matched comparison groups, but absolute differences were small and recurrent crashes were rare. MVC alone is too rare to serve as a signal of incipient ADRD, highlighting the need for more sensitive measures.
PMID:42560687 | DOI:10.1111/jgs.70630
