Driving While Old

In the United States there are more older-adults drivers on the road and as a result many will end-up in hospitals.

In 2015 there were more than 47.8 million licensed drivers ages 65 and older in the United States. The fastest growing driving population. With this increase we are also seeing more accidents. That same year 6,800 older adults were killed—compared to 2,333 teens ages 16–19—and more than 260,000 were treated in emergency departments for motor vehicle crash injuries.

A quick review of the National Institutes on Aging website on older drivers quickly provides a simplistic answer. The website that address older adults and driving includes such enlightened subheadings as: Stiff Joints and Muscles; Trouble Seeing; Trouble Hearing; Dementia; Slower Reaction Time and Reflexes; Medications. It is not surprising therefore to see that fatal crashes, per mile traveled, increases the older the driver is—particularly males. It seems that these physical diminished capacities have direct negative consequences when driving.

Despite this obvious conclusion—that diminished physiology results in more accidents—the evidence is not so clear-cut.

A 2015 report by the Insurance Institute for Highway Safety suggests that such increased fatalities are more likely due to increased susceptibility to injury and medical complications rather than the increased risk of crashing. Older people are more likely to be killed when in an accident. Frail bodies as well as driving older and less safe cars are to blame. There are a lot of older pedestrian deaths as well which does not involve them driving.

Older drivers might have impaired capabilities but they are not all impaired drivers. In fact they are safer than some younger groups. In general older drivers are more likely to use seat belts, tend to drive when conditions are safest and are less likely to drive while under the influence of alcohol. In comparison, teen drivers—at the zenith of their physiological prowess—have a higher rate of fatal crashes, mainly because of their immaturity, lack of skills, and lack of experience. It’s not all about biology.

Teenagers have taught us that driving a car requires more than just physical attributes. Even if we just focus on the most obvious, vision, the results are surprising.

Cynthia Owsley and her colleagues with the Department of Ophthalmology, University of Alabama, found that the best predictor of accidents was not visual acuity but a combination of early visual attention and mental status. Having 3-4 times more accidents (of any type) and 15 times more intersection accidents than those without these problems. Driving, it seems, primarily requires a sense of spatial awareness—knowing what is around you and predicting how objects and people are moving. This perceptual capacity is known as the “useful field of view”—the area from which you can take in information with a single glance.

The psychologist Karlene Ball and her colleagues with Western Kentucky University, reported that older adults with substantial shrinkage in the useful field of view were six times more likely to have a crash. What was surprising was that when compared with eye health, visual sensory function, cognitive status, and age—although these all correlated with crashes—they were poorer in predicting crash-prone older drivers. Our perception and how we can predict the immediate environment is more important than having excellent vision.

Our useful field of view narrows with age. We take in less of the visual field in front of us resulting in greater susceptibility for accidents. This is not a negative, although it has negative consequences. This is a result of years of excellent driving and training our brain that now we do not need to concern ourselves with peripheral events. We are such good drivers. As a result our peripheral view has become unimportant, and we have erroneously eliminated that aspect of driving at a time when it becomes important because we have started losing other sensory sharpness.

But luckily there are ways to enhance our perception. There are great computer-based tools for improving useful field of view and to retrain our brain to drive safer. As a result of training, these studies have shown that drivers make a third less fewer dangerous driving maneuvers, can stop sooner when they have to and feel greater mastery of driving in difficult conditions—such as at night, in bad weather, or in new places. All of which translates to a reduction in at-fault crash risk by nearly half. This is all good news that will ensure that older drivers can keep their license longer, and more importantly drive safer, despite having diminished physiological capacities.


© USA Copyrighted 2017 Mario D. Garrett 

References

Ball, K. K., Roenker, D. L., Wadley, V. G., Edwards, J. D., Roth, D. L., McGwin, G., ... & Dube, T. (2006). Can High‐Risk Older Drivers Be Identified Through Performance‐Based Measures in a Department of Motor Vehicles Setting?. Journal of the American Geriatrics Society, 54(1), 77-84.

Centers for Disease Control and Prevention, National Center for Injury Prevention and Control. Web-based Injury Statistics Query and Reporting System (WISQARS). Atlanta, GA: CDC; 2017 [cited 2017 Nov 29]. Available from URL: https://www.cdc.gov/injury/wisqars/index.html

Insurance Institute for Highway Safety (IIHS). Fatality facts 2015, Older people. Arlington (VA): IIHS; November 2016. [cited 2016 Dec 21]. Available from URL: http://www.iihs.org/iihs/topics/t/older-drivers/fatalityfacts/older-people/2015

Owsley, C., Ball, K., Sloane, M. E., Roenker, D. L., & Bruni, J. R. (1991). Visual/cognitive correlates of vehicle accidents in older drivers. Psychology and aging, 6(3), 403.

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