CPAP adherence a key factor in cardiovascular secondary prevention in people with OSA

By Melanie Hinze

Adherence to continuous positive airway pressure (CPAP) treatment reduces the risk of cardiovascular events in people with both established cardiovascular disease and obstructive sleep apnoea (OSA), according to research published in JAMA.

The systematic review and individual patient data meta-analysis found that adherent use of CPAP treatment for at least four hours each day was associated with a reduced recurrence risk of major adverse cardiac or cerebrovascular events (MACCEs).

The study included 4186 participants (82.1% men; mean age 61.2 years) from three randomised controlled trials. The participants had a mean body mass index of 28.9 kg/m² and a mean apnoea-hypopnoea index of 31.2 events per hour, and 71% had hypertension. Half of the participants were receiving CPAP and half were receiving usual care (no CPAP).

In an intention-to-treat analysis, the researchers found the risk of first MACCE was similar between the CPAP and the no CPAP groups. However, in an on-treatment analysis, they found that adherent use of CPAP for at least four hours a day was associated with a reduced risk of MACCE, with a significant hazard ratio of 0.69.

The researchers identified poor adherence to CPAP as a key feature associated with CPAP having little effect on secondary cardiovascular prevention.

Professor Peter Cistulli, Professor of Sleep Medicine at The University of Sydney and Director of the Sleep Investigation Laboratory, Royal North Shore Hospital, Sydney, said that the findings of this study were very welcomed as they highlighted the benefit of OSA treatment in reducing the risk of recurrent cardiovascular events in patients with OSA and existing cardiovascular disease.

‘Hence it is now clear that the previously published randomised controlled trials were neutral because the average CPAP usage was simply too low,’ he said.

‘There are important lessons for future clinical trials, which need to include patients most likely to benefit from OSA treatment, regardless of the modality, as well as the use of patient engagement strategies to optimise treatment adherence,’ Professor Cistulli added.

He told Medicine Today that it was hoped these findings would drive greater clinical collaboration between GPs, cardiologists and sleep clinics to improve the care of this high-risk population.

JAMA 2023; 330: 1255-1265.