Treating obesity with bariatric surgery increases a person’s risk of developing epilepsy by 45%, new research has shown.

The study, which looked at data from people living in Ontario, Canada, who had bariatric surgery over a six-year period, found that 0.4% of those who had the surgery went on to develop epilepsy, compared to 0.2% of people who didn’t undergo surgery.

Researchers also found that people who had a stroke following their surgery were 14 times more likely to develop epilepsy.

Study author Jorge G. Burneo, from Western University in London, Canada, and a Fellow of the American Academy of Neurology, said: “Bariatric surgery, which involves altering your digestive system, has become a more common treatment for weight loss.

“While bariatric surgery is an effective treatment for obesity and obesity-related chronic conditions like high blood pressure and type 2 diabetes, our research found that bariatric surgery recipients have an elevated risk of epilepsy.”

He went on: “When considering having bariatric surgery, people should talk to their doctors about the benefits and risks.

“While there are many health benefits of weight loss, our findings suggest that epilepsy is a long-term risk of bariatric surgery for weight loss. Future research should investigate epilepsy as a potential long-term complication of bariatric surgery, exploring the possible effects of this procedure.”

The research team compared data from almost 17,000 people who had undergone bariatric surgery with just over 622,000 people with obesity who had not had the surgery.

Using the metric ‘person-years’, which indicates both the number of people in the study and the time they spent in the study, the researchers found that rates of epilepsy were 50 per 100,000 person-years among those who had bariatric surgery and 34 per 100,000 person-years among those who had not had the surgery.

The study has been published in the journal Neurology.

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