Changes in the burden of medications that may impair driving among older adults before and after a motor vehicle crash

Abstract

Background: Medications are one of the most easily modifiable risk factors for motor vehicle crashes (MVCs) among older adults, yet limited information exists on how the use of potentially driver-impairing (PDI) medications changes following an MVC. Therefore, we examined the number and types of PDI medication classes dispensed before and after an MVC.

Methods: This observational study included Medicare fee-for-service beneficiaries aged ≥67 years who were involved in a police-reported MVC in New Jersey as a driver between 2008 and 2017. Analyses were conducted at the "person-crash" level because participants could be involved in more than one MVC. We examined the use of 36 PDI medication classes in the 120 days before and 120 days after MVC. We described the number and prevalence of PDI medication classes in the pre-MVC and post-MVC periods as well as the most common PDI medication classes started and stopped following the MVC.

Results: Among 124,954 person-crashes, the mean (SD) age was 76.0 (6.5) years, 51.3% were female, and 83.9% were non-Hispanic White. The median (Q₁ , Q₃ ) number of PDI medication classes was 2 (1, 4) in both the pre-MVC and post-MVC periods. Overall, 20.3% had a net increase, 15.9% had a net decrease, and 63.8% had no net change in the number of PDI medication classes after MVC. Opioids, antihistamines, and thiazide diuretics were the top PDI medication classes stopped following MVC, at incidences of 6.2%, 2.1%, and 1.7%, respectively. The top medication classes started were opioids (8.3%), skeletal muscle relaxants (2.2%), and benzodiazepines (2.1%).

Conclusions: A majority of crash-involved older adults were exposed to multiple PDI medications before and after MVC. A greater proportion of person-crashes were associated with an increased rather than decreased number of PDI medications. The reasons why clinicians refrain from stopping PDI medications following an MVC remain to be elucidated.

Keywords: Medicare; older adults; polypharmacy; prescription drugs; traffic accidents.