Driving Assessment

last authored: April 2011, David LaPierre
last reviewed:

 

 

 

Introduction

driving

Sequoia, courtesy of Sean Dreilinger

Driving is a complex skill set requiring physicial and mental abilities. It is important to ensure drivers are safe on the road, and this is particularly important as numbers of older drivers, often with medical conditions and medications, increases. The cause for concern is real, as the risk of motor vehicle collisions (MVCs) and injury goes up with age.

 

Decisions about driving can be difficult, given a loss of patient's autonomy and freedom, and the evaluation itself can be challenging. Family members may mention their concern to you, but patients will rarely raise it as an issue themselves. As such, it is important to consider driving safety in at-risk patients, and to have an approach for addressing this.

 

While medical conditions such as seizure, stroke, and myocardial infarction are the most frequent causes of license revocation, dementia is one of the most common reasons to consider driving assessment. Between 30-50% of patients with dementia will have at least one MVC before they stop driving. Diagnosis of dementia does not mean the patient needs to immediately stop driving, but it is critical to ask if they are driving and assess their ability.

 

 

 

Risk Factors

The following are risk factors for increased risk of driving.

general factors

  • male gender
  • increased age
  • frailty

 

medical conditions, especially those that affect alertness, ability to think clearly, or functional ability

  • cognitive (dementia)
  • neurological (seizure, stroke, Parkinson's)
  • sensory loss
  • rheumatoid arthritis, OA
  • diabetes (hypoglycemia, fatigue)
  • cardiovascular (ie syncope)
  • pulmonary
  • psychiatric
  • sleep disorders
  • recent surgery
  • dialysis

drugs

  • alcohol
  • benzodiazepines
  • tri-cyclic antidepressants
  • antihistamines
  • antiemetics
  • antipuritics
  • antispasmotics
  • other anticholinergic medications
  • narcotics
  • anticonvulsants at high doses

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Assessing Risk

There can be uncertainty regarding competence, particularly in regards to dementia. How much dementia is necessary to revoke driving privileges? If disease is moderate or severe, the case is clear. However, for mild cases, it is important to assess memory, visuospatial deficits, attention, judgment, insight.

  • history
  • physical exam
  • tests and tools

History

 

Questions

  • have you noticed any changes in your driving?
  • any MVCs, near misses, or traffic tickets in the past year?
  • have you recently restricted your driving habits (ie driving less, avoiding the dark, etc)?
  • have you ever become lost or forgotten where you are going?
  • do other drivers honk at you or show irritation?
  • do you have any functional limitations that impact your driving?

 

Past medical history

  • dementia: type (especially non-Alzheimer's), functional impact
  • stability of other medical conditions

 

Medications

  • as described above, under risk factors

Collateral history from family or friends: Would you feel comfortable with your child in the car with them?

Physical Exam

Physical exam should include the following:

  • mental status exam
    • especially aggression or impulsivity
    • hallucinations
    • delusions
    • agitation
    • anxiety, depression
  • neck range of motion
  • visual acuity, visual fields
  • reaction time

Tests and Tools

There are currently (2011) no validated tests, but research is underway. The following tests appear to be the most helpful:

  • trails A and B tests
  • clock draw
  • verbal fluency
  • copy cube
  • intersecting pentagons
  • MMSE <24 is possibly useful

10-minute office based dementia and driving guide (get link)

 

If a mildly demented patient is assessed and deemed safe to continue driving they should be reassessed at 6-12 month intervals.

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Addressing Driving Cessation

helpful phrases

"Everyone has to stop driving sometime;
it is simply a question of when."

 

"Doctor, I've been driving for 50 years without an accident!"
Respond with, "and we want to keep it that way!"

Many local ministries of transport require that physicians report potentially dangerous conditions. Tell the patient the requirements mandated by the provincial or national ministry (as appropriate), and that this is what is guiding the process. Provide a letter to them explaining as such.

 

Bring in family/friends when you have the conversation.

 

There is no evidence as yet that reduction stategies (ie license restrictions, driver training) are helpful, but studies are pending.

 

The plan depends on the circumstances. If the risk is substantial, immediately ask that they stop driving, and ask the family how they will be ensuring the person will not drive (moving the car, taking the keys). A worst-case scenario is that the family need to call police.

 

Driving tests are often provided by the Ministry of Transport. These frequently include written tests and road tests.

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Resources and References

Molnar FJ, Simpson CS. 2010. Approach to assessing fitness to drive in patients with cardiac and cognitive conditions. Canadian Family Physician. vol. 56(11) 1123-1129.

Iverson et al. 2010. Practice parameter update: Evaluation and management of driving risk in dementia: Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 74(16):1316-24.

Determining Medical Fitness to Drive (Canadian Medical Association)

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