Keywords

Introduction

America is a nation of highways. The automobile is an integral part of modern culture and a source of income, recreation, and freedom for many. Practically, the ability to drive a car allows older adults to socialize in the community, shop for essentials, and take care of themselves without being a burden on others. Many older adults may have been driving for 70 plus years. As a result, driving cessation can result in social isolation and depressive symptoms in a former driver and additional burden on the caregiver. Most older drivers are responsible drivers and are less likely than younger drivers to drive recklessly, at high speeds, or under the influence of alcohol [1]. Unfortunately, chronic medical conditions may limit the ability to drive safely, and the burden of chronic disease increases with age. The Centers for Disease Control and Prevention (CDC) reports that in 2010, motor vehicle injuries were the second leading cause of injury-related deaths among 65–85 year age group. The Fatality Analysis Reporting System data indicates that individuals aged 80 and older have a higher rate of fatality and injury in motor vehicle crashes per million miles driven than any other age group except for teenagers.

Many clinicians are not comfortable discussing driving safety with older patients . However, in reality determining an elderly person’s ability to continue driving rests on physicians’ shoulders. Therefore, clinicians are more receptive to education to improve their skills in office evaluation of the elderly drivers [2]. In this article, we’ll review some common conditions in older adults that can affect driving skills, evidence-based guidelines for driving in these conditions, and how to assess for driving safety in your patient.

Neurocognitive Disorders and Driving

Cognitive impairment due to Alzheimer’s disease (AD) can affect memory, attention span, problem-solving skills, multitasking, orientation, judgment, and reaction speed, which can impair driving skills. Individuals with AD have been observed to make more safety and lane observance errors than controls and have higher rates of motor vehicle accidents (MVA) when the driver’s approach to an intersection triggers an illegal incursion by another vehicle in simulated driving evaluations [3, 4]. Even in amnestic mild cognitive impairment , defined as very mild short-term memory deficits and slight impairment in problem-solving without functional decline, driving skills such as lane control may be impaired [5].

Frontotemporal dementia (FTD) has been associated with profound impairments in reasoning, task flexibility, planning, and execution. Persons with FTD are more likely to drive poorly, including speeding, running “stop” signs, and suffering more off-road crashes and collisions than controls [6].

Individuals with HIV-associated cognitive impairment experience impairment in executive function and visual attention and therefore are also at a higher rate of MVA compared to HIV-positive individuals without cognitive impairment [7, 8].

The diagnosis of dementia is insufficient to predict a person’s ability to drive safely. Therefore, The American Academy of Neurology has proposed using the Clinical Dementia Rating (CDR) scale to identify individuals with dementia at increased risk of unsafe driving, as there is a strong (Level A) evidence relating dementia stage to driving risk [9, 10]. In mild dementia (CDR score of 1) when memory loss is accompanied by moderate difficulty in problem-solving and functional impairment in complex activities of daily living, as few as 41 % of drivers may drive safely. There is poor correlation between an individual’s self-rating or caregiver’s rating of driving abilities as “safe,” and an on-road driving test (Level A evidence). However, a caregiver’s rating of an individual’s driving skills as marginal or unsafe is useful in identifying unsafe drivers (Level B evidence). Other “red flags” include recent traffic citations, motor vehicle accidents, self-reported situational avoidance, mini-mental state examination scores of 24 or less, or emergence of an aggressive or impulsive personality (Level C evidence) (Table 6.1) [9]. With amnestic mild cognitive impairment (CDR of 0.5), most drivers “pass” the driving evaluation, but the red flags described above may be used to guide driver evaluation referrals. Moderate to severe dementia (CDR score of 2 and 3) may result in severe impairment in memory, judgment, and ability to do complex activities of daily living. Therefore, these patents should be strongly encouraged to stop driving and use alternative means of transportation.

Table 6.1 Identifying at-risk driving patterns in individuals with cognitive impairment
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The trail-making test part B (aka Trails B) which can be administered in 3–5 min highly correlates with recent or future at-fault MVA [11, 12]. It can be employed by clinicians to screen for fitness to drive in busy office settings.

A detailed neuropsychological assessment may be useful for evaluation of memory, spatial cognition, and executive functioning if questions about the diagnosis of dementia. However, there is insufficient evidence to support referral for neuropsychological testing to assess driving risk in patients with dementia .

There is no evidence to support or refute benefit of interventional strategies as driver rehabilitation for drivers with dementia.

Parkinson’s Disease and Driving

Drivers with Parkinson’s disease (PD) have been noted to have problems with lateral position on the road at speed below 50 km/h, speed adaptations at speed above 50 km/h, turning left maneuvers, lane keeping, observing their blind spot, backing up, parking, and negotiating traffic light [13, 14]. They also have poorer vehicle control in low-contrast visibility conditions as fog and are at higher risk for crashes in these circumstances [15].

Level B evidence exists for the useful field of view, contrast sensitivity, trails B and B–A (B–A = time on trails A subtracted from time on trails B), functional reach, and Unified Parkinson’s Disease Rating Scale “off” motor scores for probably predicting driving performance [16].

Clinicians can perform functional reach test and trails B in their office for initial assessment. Individual with mild motor disability from PD may be fit for driving. They should be referred for a baseline driving evaluation upon diagnosis and then yearly for reassessment. There should be a plan to recommend cessation of driving and using alternate mode of transportation as the disease progresses. For individuals with severe motor impairment and disease severity, cessation of driving should be recommended [17].

Cardiovascular Diseases and Driving

Sudden incapacitation of the driver is estimated to be responsible for up to 3 % of all motor vehicle accidents, and approximately 10 % of these episodes are noted to be of cardiac origin [18]. Up to 35 % of all syncopal episodes while driving are neurally mediated and include neurocardiogenic syncope, situational syncope, and carotid sinus hypersensitivity constitutes. Cardiac arrhythmias (including bradyarrhythmias, supraventricular tachyarrhythmias, ventricular tachyarrhythmias) followed by orthostatic intolerance are other common causes of syncope while driving [19, 20].

Approximately 17–40 % of patients with history of syncope may have recurrences within a year of follow-up. In patients who have had a syncopal episode while driving, the actuarial recurrence of syncope is 14 % at 1 year. Driving restriction should therefore be recommended for patients with recurrent or severe syncopal episodes, until a cause is identified and symptoms are controlled. As the causes and rates of recurrence of syncope are similar in patients who have it while driving and in those who have it while not driving, driving-related recommendations also apply to both [21]. Table 6.2 lists common cardiac arrhythmias and driving recommendations for those conditions.

Table 6.2 Driving recommendations for individuals with cardiac arrhythmias
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For patients who have implantable cardioverter defibrillator (ICD) , device discharges are frequent. For individuals with history of ventricular tachycardia/fibrillation, 5 years actuarial incidence of appropriate ICD shocks ranges between 55 and 70 %. Also up to 30 % of individuals experience a syncopal or near-syncopal episode during an appropriate ICD shock [22]. However, in a survey of participants of Antiarrhythmics Versus Implantable Defibrillators (AVID) trial, none of the motor vehicle accidents were preceded by the driver receiving shock from ICD [23].

Polypharmacy and Driving

Two-thirds of people aged 65 and older take five or more medications daily. Psychoactive drugs (including benzodiazepines and tricyclic antidepressants) can result in impaired tracking and coordination, increased reaction time, and increase risk of MVA requiring hospitalization in older drivers [24]. Additionally, antiepileptics, dopaminergic medicines, muscle relaxants, hypoglycemics, antihistamines, and centrally acting muscle relaxants can affect the level of alertness and cause MVA [25]. The “Roadwise Rx” is a free online tool developed by American Automobile Association Foundation for Traffic Safety [26]. It allows a clinician (or patient) to enter the names of medicines and check if a medication can affect driving. Clinicians should also review their patients’ medications periodically to eliminate unnecessary medicines and trim down the medication lists. The Beers List, “START” (screening tool to alert doctors to right treatment), and “STOPP” (screening tool of older person’s prescriptions) tools can be useful in identifying potentially inappropriate medications [27, 28].

Vision Impairment and Driving

For safe driving, a driver should have adequate central vision to be able to see road signs, roadside objects, traffic lights, roadway markings, pedestrians, and other vehicles on the road, while the car is moving, under varying light and weather conditions. The driver should also have adequate depth perception and peripheral vision to be able to judge distance and speed and monitor objects and movement in the vicinity to identify possible threats in the driving environment. Central vision can be affected by age-related macular degeneration and cataracts, whereas glaucoma and strokes can affect peripheral vision. Cataracts can affect night vision and cause glare and contrast sensitivity.

The licensing authorities in the USA currently rely on visual acuity for vision screening for licensing purposes, which doesn’t assess peripheral vision, visual attention, depth perception, and contrast sensitivity. Therefore, state laws pertaining to vision tests have not been associated with a lower fatality rate among older drivers [29]. Clinicians should counsel patients on their driving risk based on the diagnosis and treatment potential. Drivers undergoing cataract surgeries have been noted to have improvement in visual acuity and self-reported improvement in daytime driving up to 5 years after the surgery, though it doesn’t significantly affect night driving [30]. Therefore, surgical correction of cataracts should be recommended to allow drivers with cataracts to continue driving.

Hearing Impairment and Driving

Moderate self-reported hearing loss, especially in the right ear, has been associated with higher rates of motor vehicle accidents among drivers aged 50 and older [31]. Drivers with dual sensory impairment are at a greater risk of motor vehicle accidents than those with only hearing or vision impairment [32]. Additionally, moderate to severe hearing impairment in older drivers is associated with worse driving performance in the presence of visual and auditory distracters [33].

Older adults with self-reported hearing impairment should be counseled to undergo hearing evaluation, followed by counseling to limit distracters during driving and use hearing aids if there is moderate hearing impairment. For those with severe hearing impairment or additional vision impairment, limiting driving and using alternate mode of transportation should be discussed.

Orthopedic Surgeries and Driving

A driver’s ability to navigate steering wheel or apply brakes can be affected by an injury or a recent surgery of upper or lower extremities. Postoperative pain can also cause distraction and affect safe operation of a motor vehicle. The use of casts, slings, splints, and knee and elbow immobilizers can also affect an individual’s ability to use the affected extremity to navigate the motor vehicle. Typically, impairment in driving ability is measured by changes in the time needed to perform an emergency stop. Recommendations regarding optimal time to resume driving after various elective or emergency orthopedics surgeries have been summarized in Table 6.3.

Table 6.3 Driving recommendations for individuals undergoing orthopedic procedures
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Physical Impairment and Driving Safety

Generalized physical debility as manifested by increased risk of falls can be a predictor of impaired driving skills, as both of these tasks require attention and ability to multitask. Individuals at high risk of falls, measured by Physiological Profile Assessment, have been noted to have a significantly slower response time to critical events during simulated driving assessment (400 ms slower) compared with low falls-risk drivers [34].

Epilepsy and Driving

Drivers with history of seizures run the risk of sudden incapacitation during a seizure episode, which can lead to harm to self or others if the driver is behind the wheels. However, this risk is very low if seizure disorder is controlled. Most studies show that drivers with history of seizures are not at any higher risk of MVA compared to drivers with other chronic medical conditions [35]. Physicians should refer to their state regulations governing reporting of epilepsy and breakthrough seizures.

Sleep Disturbance and Driving Safety

Sleep disorders including primary insomnia, obstructive sleep apnea (OSA) , and circadian rhythm sleep disorders can result in reduced alertness, increased sleepiness during driving, and increased risk of MVA [36, 37]. A driver exhibiting moderate to severe daytime sleepiness and a recent unintended MVA or a near-miss due to sleepiness, fatigue, or inattention is a high-risk driver. For noncommercial drivers, treatment of OSA should be encouraged to reduce risk of drowsy driving. Compliance with continuous positive airway pressure (CPAP) for at least 4 h a night for >70 % of nights is recommended [38]. Also driving restriction should be recommended till symptoms improve. There is no compelling evidence to restrict driving privileges in patients with sleep apnea if there has not been a motor vehicle crash or an equivalent event. The American Thoracic Society clinical practice guidelines recommend against the use of stimulant medicines to improve alertness during driving in individuals with OSA [39].

It is recommended that commercial drivers should undergo a screening of symptoms of OSA during in-service evaluation and further evaluation as needed. They should also undergo out-of-service evaluation if observed or confessed excessive somnolence or road traffic accidents due to increased somnolence [40].

The Copilot Phenomenon

The copilot phenomenon describes a caregiver or partner of the driver who sits beside the driver when he/she drives and gives directions. This is an extremely important red flag to look for in the at-risk elderly drivers.

Evaluation

There are three key functions for safe driving: vision, cognition, and motor/somatosensory function. The American Medical Association recommends assessment of driving-related skills (ADReS) test battery (see Table 6.4) which can be performed by a clinician in office to assess many key areas of the important functions which have been validated with driving outcomes [41]. It is important to note that ADReS is an assessment of important functional domains but is not a predictor of motor vehicle accidents. Additionally, a study by Ott et al. suggests that some of the ADReS may be better than others in assessing driving-related skills. In particular, trail-making test part B, rapid pace walk, and range of motion testing in office correlate best with on-road tests [42].

Table 6.4 Assessment of driving-related skills (ADReS) in office
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If there are concerns about a patient’s ability to drive safely, clinicians can refer the patient to a certified driver rehabilitation specialist (CDRS) for driving assessment. The driving assessment usually includes an assessment of the driver’s knowledge of traffic signs and laws, a cognitive assessment, a simulation test, and finally an on-road driving evaluation if deemed appropriate. Information about CDRS in your area can be obtained on the website of Association for Driver Rehabilitation Specialists (ADED).

In general, Medicare and other private insurances do not reimburse for driving services. The cost of driving assessment and rehabilitation is generally out of pocket and can vary from $100 to $500+ based on services provided and coverage provided by Medicare or private insurances, which varies from state to state.

How to Broach the Topic of Driving Assessment and Cessation During Your Clinic Encounter

Many older adults become defensive when driving is discussed, due to the fear that they may be asked to stop driving and may therefore lose their independence. It is best to discuss this issue directly in a non-confrontational approach, emphasizing your concern about your patient’s safety and efforts to ensure that your patient can drive safely for as long as possible. Having a family member or friend present during the conversation can be helpful. It also helps reassuring your patient that a physician or occupational therapist doesn’t have the legal authority to take away drivers’ licenses. However, physicians should inform their patients about their responsibility to report to the Department of Motor Vehicle (DMV) medical conditions that may impair safe operation of a motor vehicle.

For many patients, driving cessation may not be the immediate goal, and focusing on options for safer driving such as not driving at night time and limiting driving to familiar areas may be sufficient for a period of time with close follow-up. When the clinician feels that the elderly driver is approaching the time to “give up the keys,” discussing the importance of driving being a privilege, the safety of the patient and the safety of others should be emphasized. The American Medical Association suggests giving these drivers a prescription saying “Do Not Drive, For Your Safety and the Safety of Others.” Focusing on alternatives that may allow them to stay connected with outdoor activities and developing alternative action plans with the elderly drivers and their families may reduce anxiety and depression that can develop when the elderly relinquish their driving privileges.

Reporting an Unsafe Driver

If a clinician believes that a patient has medical conditions that may impair safe operation of a motor vehicle, and put life of the patient or others at risk, the clinician should report to the local DMV in accordance with the state’s mandatory reporting laws and standards of medical practice. The clinician should maintain the patient’s confidentiality by ensuring that only the minimally required information is reported.

Follow-Up After Driving Cessation

Driving cessation can result in decline in overall health and increased depression in a former elderly driver who may have been driving for years [43–45]. Therefore, it is extremely important to follow up after counseling your patients to stop driving, to ensure that there is an alternative transportation option in place to allow the elderly to socialize and take care of their health and daily needs.

Key Points

  1. 1.

    There are three key functions for safe driving: vision, cognition, and motor/somatosensory function.

  2. 2.

    The licensing authorities in the USA currently rely on visual acuity for vision screening for licensing purposes, which doesn’t assess peripheral vision, visual attention, depth perception, and contrast sensitivity.

  3. 3.

    The diagnosis of dementia is insufficient to predict a person’s ability to drive safely.

  4. 4.

    There is no evidence to support or refute benefit of interventional strategies as driver rehabilitation for drivers with dementia.

  5. 5.

    In evaluating medications, the “Roadwise Rx” is a free online tool developed by AAA Foundation for Traffic Safety that allows a clinician (or patient) to enter the names of medicines and check if a medication can affect driving.

  6. 6.

    Moderate self-reported hearing loss, especially in the right ear, has been associated with higher rates of motor vehicle accidents among drivers aged 50 and older.

  7. 7.

    The copilot phenomenon, which describes a person who sits beside the driver when he/she drives and gives directions, is an extremely important red flag to look for in the at-risk elderly drivers.

  8. 8.

    If a clinician believes that a patient may be unsafe to drive, he or she should report in accordance with the state’s mandatory reporting laws.

Abbreviations

ADReS:

Assessment of driving-related skills

ADED:

Association of driver rehabilitation specialists

CDRS:

Certified driver rehabilitation specialist

CDR:

Clinical Dementia Rating scale

CPAP:

Continuous positive airway pressure

DMV:

Department of Motor Vehicle

FTD:

Frontotemporal dementia

ICD:

Implantable cardioverter defibrillator

MVA:

Motor vehicle accident

OSA:

Obstructive sleep apnea

PD:

Parkinson’s disease

START:

Screening tool to alert doctors to right treatment

STOPP:

Screening tool of older person’s prescriptions