A blackout, or transient loss of consciousness (T-LOC) occurs because there is: a disorder of the circulation—syncope; a disorder of the brain—epilepsy (or other rare neurological condition); a disorder of the psyche—psychogenic seizures.

CAUSES OF BLACKOUTS: EPILEPSY OR SYNCOPE?

It is clear from referral patterns and current care pathways that many doctors assume that T-LOC is usually caused by epilepsy, but in fact syncope is more likely^1–3 (table 1). The majority are cases of reflex syncope, with up to 50% of people suffering reflex syncope during their lives. In most patients this presents as simple fainting, and many sufferers never come to neurological evaluation. However, a very significant number of patients with syncope may be misdiagnosed with epilepsy. This is a common mistake, it damages patients lives, may result in failure to respond to treatment, and may be very dangerous. For example, in the UK only about 4% of patients attending neurological clinics have an ECG recorded (http://www.nice.org.uk/pdf/CG020fullguideline.pdf). Cases of T-LOC caused by transient polymorphic ventricular tachycardia (VT) in the congenital long QT syndrome have been misdiagnosed as epilepsy. This has previously led to cardiac arrest and hypoxic brain damage in young people, after wrong treatment with antiepilepsy drugs (author’s experience). The STARS Medical Advisory Committee (STARS MAC, www.stars.org.uk), with European and North American multidisciplinary membership comprising cardiologists, paediatric and adult neurologists and general physicians, agree that this is a worldwide problem. Furthermore, close collaboration between neurologists and cardiologists is now advocated by the National Institute for Health and Clinical Excellence (NICE) guidelines (http://www.nice.org.uk/pdf/CG020fullguideline.pdf), although generally such collaboration still seems to be unusual.

Current understanding puts the prevalence of epilepsy at 0.5–1%.⁴ Syncope is thought to be more common than epilepsy, affecting 15% of children under the age of 18 years and a …