Older adults with major depressive disorder exhibited riskier driving behaviors, including more frequent hard braking and greater unpredictability, compared to their non-depressed peers, according to a recent longitudinal study.
Researchers investigated the impact of major depressive disorder (MDD) on driving behaviors among older adults in a study that followed 395 participants aged 65 years or older, including 85 with MDD and 310 without depression. The study, published in JAMA Network Open, used data from the Driving Real-World In-Vehicle Evaluation System (DRIVES) Project. Driving data were collected via vehicle data loggers, alongside clinical and neuropsychological assessments, from July 2021 to December 2023.
At baseline, participants with MDD exhibited significantly higher depressive symptom scores (mean [SD], 8.35 [5.35] vs 2.33 [2.72]; difference, 6.02; 95% CI, 5.17–6.85; P<.001) and a greater number of comorbid conditions (mean [SD], 4.08 [2.07] vs 2.79 [1.67]; difference, 1.29; 95% CI, 0.87–1.70; P<.001). They also drove more hours per month (mean [SE], 54.90 [9.94] vs 50.80 [9.69]; P=.04) and took slightly longer trips (mean [SE], 21.49 [4.05] minutes vs 19.27 [3.93]; P=.02) compared to controls.
Longitudinal analysis revealed that older adults with MDD displayed riskier driving behaviors over time. These included more frequent hard braking events (mean [SE], 3.17 × 10⁻⁴ [7.30 × 10⁻⁵] vs 6.70 × 10⁻⁵ [4.00 × 10⁻⁵]; difference, 2.50 × 10⁻⁴; 95% CI, 1.74 × 10⁻⁴ to 4.61 × 10⁻⁴; P<.001) and hard cornering events (mean [SE], 0.80 [0.64] vs 0.57 [0.25]; difference, 0.23; 95% CI, 0.08–1.06; P=.04). Participants with MDD also drove farther from home (mean [SE], 31.19 [7.35] km vs 7.76 [3.80] km; difference, 23.43; 95% CI, 0.28–15.2; P<.001) and visited more unique destinations (mean [SE], 0.34 [0.10] vs -0.27 [0.03]; difference, 0.61; 95% CI, 0.14–0.54; P<.001). Their driving patterns showed higher levels of random entropy, a measure of unpredictability (mean [SE], 0.01 [0.01] vs -0.02 [0.00]; difference, 0.03; 95% CI, -0.03 to -0.01; P<.001).
Notably, cognitive composite scores did not differ significantly between the groups, suggesting that these behaviors were more directly associated with MDD. Adjusting for antidepressant use or total medications did not alter the results, indicating that MDD was independently linked to the observed driving behaviors.
The study authors note that further research into interventions addressing mental health and mobility may improve driving safety for older adults with MDD. They also suggest that routine depression screening and tailored programs could support safer driving behaviors in this population.
Full disclosures can be found in the published study.