Consciousness loss possible after laughing in Angelman syndrome patients

In a groundbreaking study, researchers have turned their attention towards a lesser-known phenomenon in individuals with Angelman syndrome: gelastic syncope. This condition, characterised by loss of consciousness triggered by intense laughter, is a complex issue that the researchers aim to unravel in order to improve diagnosis and management of related neurological symptoms.

The study, published in Epilepsy & Behavior Reports under the title "Gelastic spells in Angelman Syndrome, when laughter isn't funny," delves into the experiences of three Angelman patients who have experienced repeated episodes of laughter followed by loss of consciousness.

Angelman syndrome, a genetic disorder marked by abnormalities in development and behaviour, is known for causing its patients to be very happy and prone to laughter. However, this joyous trait can sometimes lead to challenging situations, as laughter can lead to loss of tone, syncope (loss of consciousness), and falls.

The researchers noted that while the laughter can be delightful, it can also be worrisome due to these potential complications. They are calling for further studies to explore laughter-related episodes in Angelman patients and to test treatment options.

In cases of gelastic syncope, the first-line management involves limiting time spent standing up, drinking lots of fluids, and consuming more salt to keep blood pressure up. If these measures fail, medications such as antidepressants may be tried, but data are limited on their effectiveness in Angelman patients experiencing gelastic syncope.

One explanation for these spells is seizures triggered by laughter, called gelastic seizures, possibly secondary to hyperventilation. However, distinguishing between seizures, cataplexy, and syncope is crucial for guiding treatment. This distinction is made through detailed clinical histories, extensive talks with caregivers, and home video recordings.

Measuring the brain's electrical activity during an episode can help distinguish seizures and syncope, but this is often not practical. Instead, gelastic syncope is distinguished from seizures by these methods.

The research is significant in bringing specific awareness of gelastic syncope to clinicians and caregivers and helping to form a framework for guiding diagnosis, data collection, and treatment. The study also serves as a call to action, encouraging more research into this lesser-known aspect of Angelman syndrome.

On a positive note, the researchers expressed the joy of working with Angelman patients, noting the abundance of happiness and the ever-present and contagious laughter of the patients. The Phase 3 Aspire trial of gene therapy GTX-102 has recently dosed its first patient, offering hope for a future where the challenges of Angelman syndrome may be alleviated.