The Woolcock Institute of Medical Research

A weight-loss medication has significantly reduced sleep apnea symptoms in global-first research jointly led by the Woolcock.

In a study published in the New England Journal of Medicine on June 21, researchers tested tirzepatide in overweight or obese adults with severe obstructive sleep apnea (OSA) at 60 centres across nine countries.

Over a 52-week period, half the participants were given a weekly dose of the active medication and the other half a placebo, with the treatment group losing nearly 20 per cent of their body weight. Those in the treatment group had a reduction in sleep apnea severity of up to 63 per cent (30 fewer breathing pauses per hour) and up to 51.5 per cent of them met the threshold at which continuous positive airway pressure (CPAP) therapy may no longer be required.

‘DRAMATIC’ RESULTS

With excess weight the most common risk factor for OSA, responsible for about 60 per cent of moderate-to-severe cases, Woolcock research leader and study author Professor Ron Grunstein said sleep specialists were excited by the results.

“I've not seen any medication in sleep apnea that has actually produced such a dramatic result,” Professor Grunstein said.

“While it doesn't surprise us in a way because we knew that these medications cause significant weight loss, we didn't know how much it would improve sleep apnea. So, I think it's the first medication that really does the job.

“It also has the added advantage of improving blood glucose control, blood pressure and lipid levels not seen with other sleep apnea treatments.”

According to Professor Grunstein, the main side effects of the medication, such as nausea and diarrhoea, were easily managed.

A NEW THERAPY CHOICE

Up to 20 per cent of Australian adults are affected by OSA, a chronic disorder where breathing briefly stops and restarts during sleep. In severe cases, this can happen hundreds of times a night. As well as making people tired, untreated moderate-to-severe OSA increases the risk of other health problems, such as high blood pressure, heart attacks, strokes and diabetes, as well as increasing the risk of work and road accidents.

CPAP machines (which pump pressurised air into a mask to keep airways open) are the current gold-standard treatment for OSA, however many people find them difficult to use in the long term. Researchers hope the new treatment, which would be the first medication specifically approved to treat OSA, will offer sufferers a safe and effective alternative.

Despite the promising results, Woolcock study coordinator and dietitian Dr Claudia Harper cautioned it was important that people treated the medication as a starting point in their weight-loss journey.

“I think we need to also keep in mind that weight maintenance is another big hurdle,” Dr Harper said. “Once those drugs are withdrawn, it's good to start embedding lifestyle habits that are going to stick around for the long haul.”

The Woolcock is currently recruiting people with type 2 diabetes and possible OSA for another study with a newer, potentially more potent weight-loss medication.

Find out more

• Volunteer for the new weight-loss medication study
• The New England Journal of Medicine - Tirzepatide for the treatment of obstructive sleep apnea and obesity
• Our Sleep and Circadian Research Group