Sudden Unexpected Death in Epilepsy (SUDEP): Heart vs. Brain
Among the major global health problems today, epilepsy is one of the most complex and misunderstood. What adds to the gravity of this condition is that it is indiscriminate – males and females of all ages, ethnicities, social and geographical backgrounds may be affected. Research has shown that about 1 in 26 people could develop epilepsy in their lifetime, with the current number of affected people across the globe at well over 50 million. These sobering facts lead to the important question: how can we reduce the risk of SUDEP, and is it preventable?
This question and more were addressed in the second Sir John Monash Lecture for 2021 on “Sudden Unexpected Death in Epilepsy (SUDEP): Heart vs. Brain” by Professor Terence J. O’Brien, MD, FRACP, Chair of Medicine (Neurology), and Head of the Central Clinical School at Monash University. He opened on a positive note, mentioning that despite the tragic consequences SUDEP has had on the lives and families of people affected by epilepsy, recent research on SUDEP has been ramped up considerably, and we are finally beginning to really understand its causes.
The significance of SUDEP is that it is the most common cause and the leading neurological cause of premature death related to epilepsy, where affected people are 24 to 40 times more at risk of dying suddenly, who otherwise have few other medical reasons to die. SUDEP is also more common among young people who are typically 35 years old or younger. Professor O’Brien described this as “years lost” due to the disproportionate impact compared to the effects of strokes, heart disease, or dementia, which tend to manifest later in life.
SUDEP is generally caused by a combination of central, respiratory, and cardiac mechanisms, and may be further categorised as Definite SUDEP, Probable SUDEP, Possible SUDEP, and Near-SUDEP. Understanding these causes and definitions are crucial to coming to an accurate diagnosis in patients, which is a complicated and time-consuming process.
The societal impact of a mere 5 per cent improvement in the epilepsy cohort, or seizure freedom, is considerable, to say the least. In Australia alone, this would translate into the prevention of 811 excess deaths, 3,961 years of life gained, and A$533 million (US$364 million) less in direct healthcare costs for epilepsy. To achieve this, minimising the risk factors for SUDEP is of the highest priority.
A vital point during the lecture was the discussion of preventative measures of SUDEP, where, according to Professor O’Brien, “the most important modifiable risk factor is to control the seizure.” This can be done through medical treatment in the form of anti-epileptic drugs and surgical treatment for patients with drug-resistant epilepsy. Professor O’Brien continued to highlight major research findings from studies conducted around the world, which provide strong evidence that effective treatment for epilepsy reduces the risk of death.
Perhaps the most important thing, however, is informing patients and their families about the risks of SUDEP and raising public awareness concerning this serious but manageable condition. Professor O’Brien concluded that by discussing SUDEP with people affected by epilepsy, combined with further research to develop more effective preventative measures, we can work towards significantly reducing the number of ‘years lost’ among these people.