Driving and Epilepsy

The World Health Organisation (WHO) states that Epilepsy is characterised by recurrent seizures that are brief episodes of involuntary shaking which may involve a part of the body (partial) or the entire body (generalized) and sometimes accompanied by loss of consciousness and control of bowel or bladder function.(1)

It is a chronic non communicable disorder of the brain that affects people of all ages.

There are approximately 50 million people suffering from this condition but nearly 80% of people suffering from this condition are found in developing regions.

Estimates suggest the incidence of people in the general population with active epilepsy (those requiring continuous treatment or having continuous seizures) is between 4 to 10 people per 1,000.

However in developing countries it may be as high as between 6 to 10 people per 1000 .Furthermore, annual new cases in developed countries  are occurring at between 40 to 70 per 100 000 people in the general population.

The episodes generally occur as a result of excessive electrical discharges in a group of brain cells.

Different parts of the brain may act as the site of such discharges and the seizures can vary from the briefest lapses of attention or muscle jerks, to severe and prolonged convulsions.

The frequency of seizures may also vary from less than one per year to several per day.

Up to 10% of people worldwide may only ever have one seizure during their entire lifetime.

However one seizure does not indicate the presence of epilepsy but it is defined by the requirement of having two or more unprovoked seizures.

Regrettably the stigma of epilepsy still continues today in many parts of the world and the condition can substantially impact the quality of life for people with this disorder as well as their families.

While overall epilepsy responds to treatment approximately 70% of the time, three quarters of the affected people in developing countries do not obtain treatment for this condition 

Signs and symptoms

Characteristics of seizures may vary and depend on where in the brain the disturbance first starts, and how far it spreads. Temporary symptoms may include loss of awareness or consciousness, and disturbances of movement, sensation (including vision, hearing and taste), mood or mental function.

Generally those people with seizures tend to have more physical problems (such as fractures and bruising), as well as higher rates of other diseases or psychosocial issues and conditions like depression and anxiety.

The risk of premature death in people with epilepsy is 2 to 3 times higher than found for the general population.

Causes

Idiopathic epilepsy is the most common type with approximately 6 out of 10 people affected by this disorder with no known identifiable cause.

An underlying genetic basis ha been implicated in many cases of epilepsy.

Where the cause is known it is called secondary epilepsy or symptomatic epilepsy.

Typically this may be due to brain damage from prenatal or perinatal injuries (a loss of oxygen or trauma during birth, low birth weight); congenital abnormalities or genetic conditions with associated brain malformations; a severe blow to the head;a brain tumor.a stroke that starves the brain of oxygen; certain genetic syndromes;an infection of the brain such as meningitis, encephalitis, neurocysticercosis;

Treatment

Recent research from both developed and developing countries have shown that up to 70% of newly diagnosed children and adults with epilepsy can be successfully treated.

Their seizures may be completely controlled with anti-epileptic drugs (AEDs).

Generally after 2 to 5 years of successful treatment, drugs may be withdrawn in about 70% of children and 60% of adults without relapses.

Unfortunately around 9 out of 10 people with epilepsy in Africa go untreated.

This is because in many low- and middle-income countries, there is low availability and AEDs are not affordable and this acts as a barrier to accessing treatment.

 A recent study found the average availability of generic antiepileptic medicines in the public sector is less than 50%.

Surgery

For some people suffering from this condition, surgical intervention might be beneficial to patients who respond poorly to drug treatments.

A total of 470 patients had resective epilepsy surgery with 50 (11%) that had died since surgery. Of the remaining, 253 (60%) were contacted with mean follow-up of 10.6±5.0 years (27% of patients had follow-up of 15 years or longer). (2)

Of those patients surveyed, 32% were seizure-free and 75% had a favorable outcome (classes I and II).

Favorable outcomes had significant associations with temporal resection (78% temporal vs 58% extratemporal, p=0.01) and when surgery was performed after scalp EEG only (85% vs 65%, p<0.001).

Most significantly, favorable and seizure-free outcome rates remained stable after surgery over long-term follow-up [i.e., <5 years (77%, 41%), 5-10 years (67%, 29%), 10-15 years (78%, 38%), and >15 years (78%, 26%)].

Compared to before surgery, patients at the time of the survey were more likely to be driving (51% vs 35%, p<0.001)).

 A large majority of patients (92%) considered epilepsy surgery worthwhile regardless of the resection site, and this was associated with favorable outcomes (favorable=98% vs unfavorable=74%, p<0.001).

These findings indicate that resective epilepsy surgery yields favorable long-term postoperative seizure and psychosocial

Prevention

While idiopathic epilepsy may not be preventable, preventive measures can be applied to the known causes of secondary epilepsy.

Preventing a head injury is a very effective way to prevent post-traumatic epilepsy.

Improved perinatal care may reduce new cases of epilepsy caused by birth injury.

Drugs and other methods to lower the body temperature of a feverish child may reduce the chance of subsequent convulsions.

Elimination of parasites in tropical environments and education on how to avoid infections may also be effective ways to reduce epilepsy worldwide, for conditions such as neurocysticercosis.

Social and economic impacts

Epilepsy may account for 0.5% of the global burden of disease which is a time-based measure that combines years of life lost due to premature mortality and time lived in states of less than full health.

There are significant economic implications in terms of health-care needs, premature death and lost work productivity.

In India, a study calculated that the total cost per epilepsy case was US$ 344 per year (or 88% of the average income per capita).

For the estimated 5 million cases in India, this translates to a total cost equivalent to 0.5% of gross national product.

However in a German study of 359 patients, the majority of patients had a long-term seizure remission for more than one year (n=200, 55.7%)

For more than two thirds of patients anti-epileptic drug (AED) was prescribed as monotherapy (n=248, 69.1%) with the most frequently prescribed drugs being levetiracetam (31%), lamotrigine (26%) and valproate (24%).

Their total annual direct costs amounted to €1,698 per patient with anticonvulsants (59.9% of total direct costs) and hospitalisation (30.0%) as the main cost factors. (3)

Of the 252 (70.2%) of patients that were of working age, annual costs due to absenteeism amounted to € 745 per patient.

Drug Costs for patients aged 65 years and older were lower due to prescriptions of older anti-epileptic drugs.

Some of the challenges that people with epilepsy experience are reduced access to health and life insurance, a withholding of the opportunity to obtain a driving license, and barriers to enter particular occupations, among other limitations.

Incidence of Motor Vehicle Crashes with Epileptic Patients

In a Canadian study (4), individuals with and without epilepsy were identified using linked administrative databases between 1996 and 2003 in a Canadian health region with a 1.4 million population.

The incidence of motor vehicle accidents (MVAs), attempted or completed suicides, and inflicted injuries was assessed during 2003-2004. The outcomes were adjusted using the Elixhauser comorbidity index.

10,240 individuals with epilepsy and 40,960 individuals without epilepsy were identified.

One-year odds ratios before and after adjustment for comorbidity were 1.83 (95% confidence interval [CI] 1.33-2.54) and 1.38 (95% CI 0.97-1.96) for MVAs, 4.32 (95% CI 2.79-6.69) and 1.32 (95% CI 0.81-2.15) for attempted or completed suicides, and 3.54 (95% CI 2.66-4.72) and 1.46 (95% CI 1.04-2.03) for injuries inflicted by others.

Their conclusion in this cohort-controlled population-based study was that once important medical and psychiatric comorbidities were adjusted for, people with epilepsy were not more likely to attempt suicide or experience MVAs, but were still more likely to be assaulted compared to those without epilepsy.

However, in a study of patients with epilepsy in western China conducted between October 2012-October 2013 they had found that in a total of 657 patients 128(19.5%) had driven in the past year. (5)

Furthermore, 80 (62.5%) of these patients experienced a least 1 seizure in the previous year .A logistic regression suggested that age, being married, being male, possessing a higher personal income, experiencing no seizure while awake, and taking fewer antiepileptic drugs were independently associated with recent driving.

The researchers found that a considerable proportion of patients continue to drive despite uncontrolled seizures.

They also suggested that more detailed and operational driving restrictions may be needed for patients in China to obtain a better balance between patient’s quality of life and public safety.

In Thailand 203 patients with epilepsy were randomly recruited from the university epilepsy clinic in Khon Kaen, who subsequently completed an interview and a questionnaire. (6)

The researchers found that 84.5% of patients that operated a vehicle on a regular basis (defined as more than 3 days a week) that 21.6% of these patient had been involved in a vehicle crash.

Furthermore, 25.6% of the patients had been involved in falls with injuries.

Of the respondents, 43% had been involved in either a car vehicle crash or a fall with an injury and 39.7% of these accidents resulted in these patients obtaining moderate to severe injuries.

The compliance of patients with their medication was estimated at 66% and 59.1% said that they had little or no control over their seizures.

More than half the patients were not confident in their ability to take care of themselves or to take their antiepileptic drugs properly.

A multivariate model, found that being single, attaining a secondary or higher education, exercising at least three times a week, napping every day or more frequently, and having poor seizure control significantly increased the risk of being in either a vehicular crash or a fall with an injury.

A Danish study found that drivers with epilepsy are more likely than healthy controls to be treated at a casualty department after having a motor vehicle accident. (7)

The authors examined a 10-year historical cohort register study of 159 subjects with epilepsy and 559 controls individually matched for age, gender, place of residence, and exposure period was carried out.

All subjects had nonprofessional driver's licenses without restrictions.

Patients with recorded diagnoses of other neurologic diseases, psychoses, diabetes, seizures, abuse, or poisoning of any kind were excluded.

The outcome measure was treatment at the casualty department after an accident as a car driver.

10 patients with epilepsy and 5 controls had been treated at the casualty department with the rate per 1,000 person-years with exposure being seven times higher (CI 2.18 to 26.13) in those with epilepsy than in the control cohort.

Licensing of Drivers with Epilepsy

In NSW Australia, a drivers license will normally only be issued if you have been free of seizures for at least one year. A condition is applied to your license that you must undergo regular medical reviews with your treating doctor or specialist. (8)

For the United States, the required time period for seizure-freedom ranges from about 3 to 12 months, depending on individual state laws (9).

Interestingly when a time trend study with analysis of motor vehicle crash reports in the state of Arizona 3 years before (1991-1993) and 3 years after (1994-1996) the seizure-free interval was decreased from 12 to 3 month, there was no significant increase in the rate or seizure related crashes. (10)

However, a 3-month seizure-free interval is recommended in the consensus statement issued by the American Academy of Neurology (AAN), American Epilepsy Society (AES), and the Epilepsy Foundation (EF) (11).

Commercial driving restrictions for people with seizures or epilepsy in the United States differ from those pertaining to use of personal vehicles (12).

Unless a person has been off seizure medication and been seizure free for at least 20 years, federal regulations specifically prohibit interstate commercial driving licensure for individuals with epilepsy years (12).

Furthermore, an individual with a single unprovoked seizure must be off seizure medication and seizure-free for at least 5 years.

At the moment, people who take anticonvulsant medications are unconditionally prohibited from licensure for interstate commercial driving (11, 12).Furthermore, State laws for intrastate (i.e., not across state lines) commercial driving have gradually shifted to the federal standard (12, 13)

Disobedience and Driving in Patients with Epilepsy

Tatum and colleagues in Florida attempted to characterize and quantify driving risk in patients with seizures (PWS) (14)

They delivered 12-question surveys to 287 consecutive PWS at an epilepsy clinic in Florida to analyse Illegal and disobedient driving practices.

They found that 83 of 236 (35.2%) PWS were eligible to drive and 62.3% were ineligible with a seizure in <6 months (P<0.001, 95% CI: 0.57-0.70).

Among the ineligible responders, 23.8% (35/147) of ineligible responders were found to be driving illegally (14.83% of cohort); 11.86% (28/236) of PWS were disobedient refusing to obey the law, and 8.9% (21/236) of PWS were defiant and knew the law.

The most common reaction to restriction was sadness (75/236, 31.8%) but disobedient PWS were angry (10/28, 35.7%).

When is it safe to return to driving following first-ever seizure?

Brown and colleagues recently studied 1386 patients with first-ever seizure that were prospectively analysed. Survival analysis was used to evaluate Seizure recurrence. (15)   

They calculated both the duration of non-driving required for a range of risks of seizure recurrence and the accident risk ratio (ARRs) was calculated.

Furthermore they prospectively determined during follow up the actual occurrence of seizures while driving.

They found that for a risk of seizure recurrence to fall to 2.5% per month, this  corresponded  to a monthly risk of a seizure while driving of 1.04 per thousand and an ARR of 2.6, non-driving periods of 8?months are required for unprovoked first-ever seizure, and 5?months for provoked first-ever seizure.

These researchers also found that for patients with seizure recurrence, 14 (2%) the monthly risk fell to less than 1/1,000 after six months.

CONCLUSION:

Overall, only a small number of patients with seizures are disobedient and illegally driving.

They require a targeted approach to high-risk drivers with repeated verbal and supplemental driving information that may help avoid unnecessary universal physician reporting for PWS

Where patients' poor medication adherence and lack of confidence in managing their seizures may contribute to accidents, they should be counselled to seek less risky behaviours and encouraged to attend classes that provide education on Anti Epileptic Drug management.

References: 

(1) World Health Organisation Fact sheet No 999 October 2012 https://www.who.int/mediacentre/factsheets/fs999/en/

(2) Wasade VS, Elisevich K, Tahir R, Smith B, Schultz L, Schwalb J, Spanaki-Varelas M. Long Term seizure and psychosocial outcomes after resective surgery for intractable epilepsy. Epilepsy Behav 2015 Feb; 43:122-7.doi: 10.1016/j.yebeh.2014.11.024.Epub 2015 Jan 19.

(3) Noda AH, Hermsen A, Berkenfeld R, Dennig D, Endrass G, Kaltofen J, Safavi A, Wiehler S, Carl G, Meier U, Elger CE ,Menzler K, Knake S, Rosenow F, Strzelczyk A. Evaluation of costs of epilepsy using electronic practice management software in Germany. Seizure 20 15 Mar; 26:49-55. doi: 10.1016/j.seizure.2015.01.010. Epub 2015 Jan 28.

(4) Kwon C, Liu M, Quan H, Thoo V, Wiebe S, Jette N. Motor Vehicle accidents, suicides, and assaults in epilepsy: a population-based study. Neurology 2011 Mar 1; 76(9):801-6. doi: 10.1212/WNL.0b013e31820e7b3b. Epub 2011 Feb 2

(5) Chen J, Yan B, Lu H, Ren J, Zou X, Xiao F, Hong Z, Zhou D. Driving among patients with epilepsy in West China. Epilepsy Behav. 2014 Apr; 33:1-6. doi: 10.1016/j.yebeh.2014.01.020. Epub 2014 Feb 19.

(6) Saengsuwan J, Laohasirjwong W, Boonyaleepan S, Sawanyawisuth K, Tiamkao S, Talkul A. Seizure-related vehicular crashes and falls with injuries for people with epilepsy (PWE) in northeastern Thailand. Epilepsy Behav.2014 Mar; 32:49-54. doi: 10.1016/j.yebeh.2013.12.021. Epub 2014 Jan 28.

(7) Lings S. Increased driving accident frequency in Danish patients with epilepsy. Neurology.2001 Aug 14:57 (3): 435-9

(8) Road and Maritime Services. ? Roads and Maritime Services Last Updated: 06 March 2015 https://www.rms.nsw.gov.au/roads/licence/health/fit-to-drive.html

(9) Krauss GK, Ampaw L, Krumholz A. Individual state driving restrictions for people with epilepsy in the US. Neurology. 2001; 57:1780–1785. [PubMed]

(10) Drazkowski JF, Fisher RS, Sirven JI, Demaerschalk BM, Uber-Zak L, Hentz JG Labiner D. Seizure-related motor vehicle crashers in Arizona before and after reducing the driving restriction from 12 to 3 months. Mayo Clin Proc.2003 Jul: 78 (7):819-25

(11) American Academy of Neurology, American Epilepsy Society, Epilepsy Foundation of America. Consensus statements, sample statutory provisions, and model regulations regarding driver licensing and epilepsy. Epilepsia. 1994; 35:696–705. [PubMed]

(12) United States Department of Transportation. Federal Highway Administration Regulations. Washington, DC: Federal Highway Administration; 1983. US Department of Transportation 49 CFR section 391.41(b) (7, 8, 9)

(13) U.S. Department of Transportation's Federal Motor Carrier Safety Administration. Expert Panel Recommendations: Seizure Disorders and Commercial Motor Vehicle Drivers Safety. 2007d. October.

(14) Tatum WO, Worley AV Selenica ML. Disobedience and driving in patients with epilepsy. Epilepsy Behav.2012 Jan; 23(1):30-5. doi: 10.1016/j.yebeh.2011.10.015. Epub 2011 Nov 22.

(15) Brown JW. Lawn ND, Lee J, Dunne JW. When is it safe to return to driving following first-ever seizure? J Neurol Neurosurg Psychiatry 2015 Jan;86(1):60-4. doi: 10.1136/jnnp-2013-307529. Epub 2014 Apr 25.