Personalized CPAP treatment could reduce cardiovascular risk in sleep apnea patients

Findings suggest a personalized approach to recommending CPAP machines to patients with obstructive sleep apnea may decrease adverse cardiovascular events.

Obstructive sleep apnea (OSA), where blockages in the airways cause breathing to uncontrollably stop and start during sleep, is a common sleep-related breathing disorder. Continuous positive airway pressure (CPAP) machines can reduce interrupted sleep for patients with OSA. While CPAP improves symptoms, it has been unclear whether CPAP also reduces the risk of heart disease. A new study by investigators from Mass General Brigham aimed to understand if using a CPAP machine could also protect the heart and brain from cardiovascular events in people with OSA. Their findings, published in European Heart Journal, suggest that a more personalized approach for treating patients is needed-one that focuses on CPAP treatment for those who stand to gain the most, while exercising caution for those who may not benefit and could even be harmed.

Through our study, we found a subgroup of patients who experience cardiovascular benefits from CPAP use. This is the first step in making better therapeutic recommendations for patients with obstructive sleep apnea in the future to reduce their risk of heart attack, stroke, and death."

Ali Azarbarzin, PhD, first author of the Division of Sleep and Circadian Disorders at Brigham and Women's Hospital

The research team analyzed data from three previous trials of patients with OSA and cardiovascular disease. The study included 3,549 total patients with a median age of 61 years-half using CPAP, half not. They tracked the patients for three years on average, looking at incidence of cardiovascular mortality, stroke and heart attack.

Overall, 16.6% of patients using CPAPs had major cardiac events, compared to 16.3% of patients not using CPAPs. While there was no statistically significant difference between outcomes for patients split between CPAP and no-CPAP, a statistically significant difference did appear when these patients were further split into those with sleep study markers of high- and low-risk OSA. Patients were classified as high-risk if they had large drops in blood oxygen levels or their heart rate spiked during breathing disruptions.

For those with high-risk markers, CPAP use lowered cardiovascular risk by about 17%. For those with low-risk markers, CPAP use was associated with an increased cardiovascular risk by about 22%. When the high- and low-risk groups were further sorted based on their daytime symptoms-asymptomatic non-sleepy or symptomatic sleepy-those trends were even stronger. Non-sleepy patients with high-risk markers experienced 24% fewer cardiovascular events, while non-sleepy patients with low-risk markers experienced 30% more cardiovascular events.

"Changing the clinical practice is going to require a further prospective study to validate our findings," said Azarbarzin. "In the meantime, patients with OSA should speak with their doctors to weigh the potential risks and benefits of different treatment options. These conversations can begin the process of personalizing obstructive sleep apnea care and reducing cardiovascular events in this vulnerable population."