These Are the Predictors of Driving Cessation Among Older Adults

The female sex, progression to cognitive impairment, and poor cognitive performance can independently increase the risk for driving cessation in older adults, according to study results published in Neurology.

Identifying risk factors for driving cessation is important to inform clinical outcomes and planning for driving retirement in older adults.

Researchers of a prospective observational study determined the factors associated with driving cessation in a community cohort of older adults.

Participants were enrolled in the aging and driving studies at the Knight Alzheimer Disease Research Center and The DRIVES Project at Washington University School of Medicine. Study eligibility criteria included age 65 and older; having a collateral source; active driving at least once a week; willingness to complete all clinical, neurologic, and neuropsychologic assessments; and fulfilment of requirements for “normal” cognition on the Clinical Dementia Rating (CDR) scale.

Global CDR scores were based on domains such as memory, orientation, judgement and problem-solving, and personal care. Cognitive normality to impairment was defined as a CDR score of 0.5 or greater. Neuropsychologic assessments included the Montreal Cognitive Assessment (MCA) and the preclinical Alzheimer cognitive composite (PACC) scores. In addition, biomarkers were collected using positron emission tomography (PET) amyloid imaging and cerebrospinal fluid (CSF).

Out of a total of 540 individuals (mean age, 72; women, 51%; White, 85.6%), 283 received PET and 257 received CSF. Mean follow-up was 5.62 years. One-third of the cohort had preclinical Alzheimer disease (AD).  

Results of the amyloid imaging model analysis showed that age (hazard ratio [HR], 1.11; 95% CI, 1.03-1.21; P =.005), the female sex (HR, 3.38; 95% CI, 1.30-8.82; P =.013), higher PACC score (HR, 0.43; 95% CI, 0.26-0.72; P <0.001), and CDR progression (HR, 5.39; 95% CI, 0.26-0.72; P <.001) were significant predictors of increased risk for driving cessation.

Based on CSF analysis testing, the female sex (HR, 3.58; 95% CI, 1.27-10.2; P =.016), higher PACC score (HR, 0.32; 95% CI, 0.14-0.72; P =.006), and CDR progression (HR, (HR, 4.14; 95% CI, 1.71-9.88; P =.002) were all significantly associated with increased risk for driving cessation.

Participants with preclinical AD, using CSF biomarkers p-Tau and t-Tau, were 3 times more likely to have driving cessation (HR, 2.91; 95% CI, 1.28-6.59; P =.012 and HR, 2.82; 95% CI, 1.23-6.44; P =0.14, respectively), with age increasing the risk by 15%. However, in the full model, progression to cognitive impairment, based on PACC and CDR scores, was associated with greater risk for driving cessation.

Limitations of the analysis included lack of longitudinal data for all participants; the homogeneity of the study population; and the small number of participants who stopped driving after follow-up.  

“The results emphasize the need for early planning and conversations about driving retirement in the context of cognitive decline and the immense value of clinical measures in determining functional outcomes,” the researchers concluded.