ADHD & Driving DR Emad Farrag MBBCh, MRCPsych Consultant Child & Adolescent PSychiatrist

A bit of humour

My favourite Quote ADHD, driving and texting; A deadly combination

A Car Story

Unintentional Injury Growing global concern In 2000, approx. 5 million died worldwide due to injuries 2/3 were unintentional, most were due to RTAs 50 million worldwide injured in RTAs Leading cause of death in Children, adolescents & young adults in affluent countries Recent figures show approx. 6 million RTAs in USA  above 40 million deaths + 3 million injuries It was estimated in 2004 alone US economy cost in excess of $200 billion

Other costs to consider Personal mental health trauma Physical mortality and disability Economic rehabilitation of injured or disabled Days off work Loss of driving licence Possible custodial sentence

DVLA & ADHD You may need to tell DVLA if you have attention deficit/hyperactivity disorder (ADHD). You can be fined up to £1,000 if you don’t tell DVLA about a medical condition that affects your driving. You may be prosecuted if you’re involved in an accident as a result.

‘Accident proneness’ A man drives as he lives (Tillman & Hobbes 1949)

Personal Attributes other than ADHD Being male Anger management problems Drug and alcohol use and abuse Antisocial tendencies Risk taking behaviour Non conformity Occupation & educational status inversely proportionate to RTAs

Theories Psychosocial theory Model of high risk driving related to states of high stress Problem behaviour theory Emphasis on lifestyle factors Reduced parental involvement Negative parental or peer influence  related to risky driving and negative driving outcomes

Cognitive abilities Inattention and distractibility (1/4 of RTAs) Poor risk perception Reduced judgement & reasoning while driving Normal brain maturational immaturities in the young (areas of the brain responsible for executive function + Inexperience driving  Contribute to increased risky driving behaviours

Do studies show a relationship? Yes but data differs and controlling for variables change the strength of the relationship; but there is an established relationship Some use ADHD status (severity) alone Others used categorical diagnosis (more here) Using both showed even higher rates

Observational Studies Significantly increased driving citations in ADHD vs. control group Speeding, suspensions, driving without licence, tail gaiting Increased citations for those with comorbid ODD/CD in males In one study looked at ADHD & age vs. effect on driving (Driving Behaviour Questionnaire): >40 years old  Normalised error scores >30 years old  Normalised violation scores Better driving with experience OR better avoidance of detection?

Simulator Studies Increase scrapes Increased steering variability Poor steering control  may reflect poor motor control and coordination

Cognitive abilities related to driving Inattentiveness (especially visual)  late response counter measures Impulsiveness  speeding & inability to disengage from risky manoeuvres Slow processing Distractibility Problem with visual memory

Treatment effect? IR-MPH Wears off and has implications for night drivers Better response inhibition and improving visual memory than dexamphetamine XL-MPH Longer availability (advantage)

How does it help? Treatment mediates the improved driving by: Improving executive functioning Particularly tasks of complex attention Response inhibition

What next? Do we screen for risky behaviours? Implications? Reporting ADHD drivers deemed to be at risk of problem driving? No law to say ADHD sufferers must take medication? Would that be discriminatory? Is there a role for motivational interviewing (modify change especially around compliance?) Issue of drug driving and stimulant treatment? Road safety is a public health problem so do we need a public health approach?

Thank you for listening & Drive safely