People with sleep apnoea at risk of heart disease post-surgery: Study from Hong Kong

PHOTO: Unsplash

People who have a sleep breathing disorder are twice as likely to develop heart diseases, particularly cardiac arrest, after undergoing surgery, according to results of a global study.

Obstructive sleep apnoea (OSA) causes breathing to repeatedly stop and start during sleep and a common sign of the disorder is loud snoring.

It affects nearly a billion people worldwide, with about 5 per cent of middle-aged men and 2 to 3 per cent of women suffering from the condition.

READ ALSO: Which is the right type of pillow for you?

However, the lack of recognition of the disorder can lead to complications following surgery for some patients, said researchers at Chinese University (CUHK) who were involved in the study published in The Journal of the American Medical Association.

"Our findings show the risk of post-operative cardiovascular events in patients with unrecognised severe OSA is significant and twice those without the disorder," said Matthew Chan Tak-vai, the principal investigator of the study and professor at CUHK's Faculty of Medicine at a press conference on Tuesday.

The study involved 1,218 patients aged 45 and above recruited from Hong Kong, Singapore, Malaysia, Canada and New Zealand.

OSA patients often have other health issues such as obesity. PHOTO: Unsplash

They had not been diagnosed with OSA, were undergoing non-cardiac surgery and had one or more risk factors of post-surgery heart complications.

The patients were given sleep tests before surgery and completed a 30-day follow-up after the operation.

Researchers found almost 70 per cent of the patients had undiagnosed OSA, while 11 per cent had severe OSA.

Thirty per cent of patients with severe OSA and 22 per cent of patients with moderate OSA suffered from heart diseases such as congestive heart failure or stroke.

By comparison, only 14 per cent of patients without OSA had heart problems within 30 days of their surgery.

"OSA patients often have other health issues such as obesity. Given the evidence from this study, we believe a preoperative OSA screening should be performed in any non-cardiac surgery," said David Hui Shu-cheong, the chairman and Stanley Ho professor of respiratory medicine.

"If OSA patients were to be recognised before surgery and provided with appropriate care, these cases might be prevented and ease the burden on patients and hospitals," Chan said.

The researchers recommend patients be screened with a simple survey, which included assessment of snoring, tiredness, observed apnoea, high blood pressure, body mass index, age, neck circumference and gender before non-cardiac surgery to identify high-risk patients.

They should then be transferred for sleep tests and long-term treatment for the condition.

This article was first published in South China Morning Post. 

Purchase this article for republication.