CPAP Risks May Exceed Benefits for Low-Risk Sleep Apnea: Study

Researchers recommend doctors assess each patient’s individual risks, particularly as a number of issues have come to light with these kinds of ventilator machines in recent years.

A new study indicates that using a CPAP machine failed to significantly reduce the risk of heart disease in people with sleep apnea, raising questions about how frequently the devices are recommended for individuals with even minor sleep disturbances.

According to findings published in the European Heart Journal on August 5, using a CPAP machine reduced the risk of cardiac events among patients with high risk sleep apnea markers, but the risk of cardiac events increased among patients with low risk markers of sleep apnea.

Continuous positive airway pressure (CPAP) machines provide constant air pressure to help a person with sleep apnea breathe while they sleep. The user wears a mask with a hose attached that pumps the continuous pressure.

The devices have been promoted for years as an effective treatment for sleep apnea, which is a sleep disorder that causes people to stop breathing momentarily during sleep. Often, they stop breathing repeatedly throughout the night.

The most common type is obstructive sleep apnea caused by a block in the airway. Symptoms can include snoring, gasping for air, daytime sleepiness and difficulty concentrating. Left untreated, it can cause other health problems like cardiovascular disease.

For this study, researchers from the Brigham and Women’s Hospital and Harvard Medical School reviewed the data from three randomized trails that treated sleep apnea patients with CPAP machines.

Led by Dr. Ali Azarbarzin, the team found that, among the 3,500 participants, the rate of cardiovascular or cerebrovascular events was the same (16%) in both the group that used CPAPs and the usual care group. There was no benefit to using a CPAP among sleep apnea patients as a whole, the researchers determined.

However, when they examined the effect among users with high- and low-risk sleep apnea markers, the results were different.

Among high-risk sleep apnea patients, using a CPAP lowered the risk of cardiovascular side effects by 17%. However, among low-risk sleep apnea patients, using a CPAP actually increased the risk of cardiovascular events by 22%.

High-risk patients were defined in the study as those with large drops in blood oxygen levels during sleep or heart rate spikes during breathing disruptions. Low-risk patients don’t experience either of those issues.

When the high and low risk groups were sorted further by daytime symptoms — sleepy with and without symptoms — the heart risks increased. Among non-sleepy asymptomatic patients who were high-risk the rate of cardiovascular disease dropped by 24%. However, non-sleepy low-risk patients experienced a 30% increase in cardiovascular events.

Researchers said the data indicates only patients with high-risk sleep apnea experience a benefit from using a CPAP, while those who are low-risk face an increased risk of adverse health events.

It is possible that patients in the low-risk group suffered a stretch in the lungs in a way that stressed the cardiovascular system, researchers hypothesized. They also said it could be because it disturbs their sleep, which affects their health, but more research is needed to determine exactly why the risk increased for low-risk sleep apnea patients.

The researchers concluded that it is important for doctors to assess sleep apnea patients individually and by phenotype to identify who may be low or high risk. Then they should work to determine who would benefit from using a CPAP and only focus on high-risk patients.

CPAP Recall Problems

This is not the first indication of increased risk connected to CPAP machines. In recent years, a number of recalls have plagued Philips Respironics CPAP machines due to defective sound abatement foam that led to interrupted therapy and a number of injuries linked to the problem.

More than 350 patients died, thousands were injured, and more than 100,000 medical device reports were filed due to problems connected to Philips CPAP machines. The injuries caused by the CPAP machines led to a number of lawsuits and a $1.1 billion settlement to resolve the claims.

Earlier this month, a class I recall was issued for Philips Respironics BiPAP machines, which is a separate kind of ventilator from a CPAP, and is also used to treat sleep apnea. The recall indicated a problem with the machine alarm led to interrupted therapy in patients, causing low blood oxygen, elevated carbon dioxide, respiratory failure and death. So far, at least eight patients have died in connection to this latest Philips ventilator machine recall.

Sign up for more health and legal news that could affect you or your family.