A continuous positive airway pressure (CPAP) machine is a medical device that’s widely used to treat sleep apnea, a sleep disorder that can lead to serious health issues. CPAP devices are used to keep a person’s airways open while they sleep. In 2021, some research indicated that CPAP use may be associated with a risk of cancer, including lung cancer. Because of this, certain CPAP devices were recalled and taken off the market.

Some confusion remains about the link between CPAP and lung cancer. Here’s what we know.

Sleep Apnea, CPAP, and Lung Cancer

CPAP machines are used to treat two types of sleep apnea, obstructive sleep apnea (OSA) and central sleep apnea, which is less common. Sleep apnea is a disorder that interrupts breathing during sleep. People with sleep apnea experience sleep disturbances and poor sleep throughout the night, even if they aren’t aware of it. Snoring loudly, stopping breathing, and gasping for air while sleeping are symptoms of sleep apnea. Another common symptom is excessive daytime sleepiness.

People with sleep apnea don’t get enough oxygen while they sleep. The condition increases the risk of serious health problems, including hypertension (high blood pressure), heart failure, type 2 diabetes, metabolic syndrome, liver disease, and problems with anesthesia and surgery.

Because of the serious risks associated with sleep apnea, CPAP therapy can be a lifesaving treatment.

How CPAP Works

A CPAP device filters and pressurizes air. A motor the size of a toaster takes in air, processes it, and sends it through a tube that attaches to a mask. The mask is worn while sleeping, and the mildly pressurized air works to keep airways open for clear breathing. People with sleep apnea need to use a CPAP device anytime they sleep, night or day.

Common risks associated with using CPAP machines include runny nose, nosebleeds, dry mouth, and congestion. Some people experience irritation from the mask. Abdominal discomfort and bloating are considered serious side effects that may need urgent medical care.

CPAP and the Risk of Cancer

A widely reported controversy over CPAP machines and lung cancer emerged in 2021, when the company Philips Respironics (Philips) recalled several lines of its respiratory devices, including CPAP machines and BiPAP (bilevel positive airway pressure) machines, which function similarly. The recall affected about 15 million devices around the world, many of which may still be in use.

Philips had determined that a breakdown of polyester-based polyurethane foam insulation — designed to control noise and vibration in the machines — could release fine particles and chemicals into the ventilation tubes and be inhaled or swallowed, which could be a health risk. In lab studies with mice, polyurethane has been found to be a carcinogen (cancer-causing substance) when inhaled or swallowed.

One study indicated that 4.6 percent of the people who used a Philips CPAP machine developed some type of cancer. However, the authors emphasized that although the number of reported cancer cases in relation to CPAP rose dramatically with the recall, more people may have reported cancer precisely because a CPAP recall was in effect.

Furthermore, the study pointed out that in the United States, cancer rates among the general public are approximately 18 percent for women and 22 percent for men. The authors concluded that more research is needed to fully understand if use of Philips CPAP machines caused an increased risk of cancer.

Cancer Rates May Not Be Higher With CPAP Use

Another study indicated that cancer rates — including lung cancer rates — among 6,903 people using Philips breathing devices were no higher than cancer rates among people using CPAP devices made by other companies. However, the researchers acknowledged that their follow-up period of 7.5 years may not have been long enough for some cancers to develop.

Other study findings indicated that particles and chemicals released by CPAP machines taper off shortly after the device is first put into use. This may have reduced the potential risk associated with recalled CPAP machines.

Sleep Apnea and Cancer Risk

In a 2022 analysis of 22 medical studies on the link between obstructive sleep apnea and cancer, researchers found that 46 percent of people with cancer also had OSA. People with obstructive sleep apnea developed cancer at a 50 percent rate than those without OSA. The analysis included a total of more than 32 million people.

Some medical researchers believe the connection between sleep apnea and cancer may be at least partly caused by hypoxia — low levels of oxygen in the body — which occurs in sleep apnea when breathing is interrupted. Low oxygen levels are believed to cause widespread inflammation, damage cells due to oxidative stress, and possibly promote tumor growth.

OSA has also been linked to other types of lung disease such as asthma and chronic obstructive pulmonary disease (COPD). OSA and lung cancer share some risk factors, including:

• Smoking
• Getting older
• Having obesity
• Having other respiratory problems or diseases

Abnormal Sleep May Increase the Risk of Lung Cancer

Medical researchers have also found that lack of sleep, which may be caused by sleep disturbances such as sleep apnea, may raise the risk of lung cancer. A systematic review of 11 studies showed that people who slept less than seven hours a night had a 13 percent higher risk of lung cancer than those who regularly logged seven to eight hours. Averaging more than eight hours of sleep a night increased lung cancer risk by 22 percent.

Potential Benefits of CPAP With Lung Cancer

Interestingly, CPAP may benefit some people with lung cancer in ways that have nothing to do with sleep apnea. One small study investigated the benefits of using CPAP for a month following lung cancer surgery. Compared to those who received standard care, those who used CPAP had:

• Better appetites and breathing
• Less weight loss
• A lower incidence of pulmonary encephalopathy (a condition that causes brain problems such as confusion and memory loss)

Discuss CPAP With Your Doctor

If you have questions about CPAP, be sure to talk to your doctor. If you use a CPAP machine for sleep apnea and are concerned about possible harm, you and your health care team can discuss the benefits and risks of CPAP. Your doctor can also help determine if you’re using a recalled CPAP device.

If your doctor has prescribed CPAP to treat your sleep apnea, don’t change your treatment plan without medical advice. Your health care team can also make sure you’re using CPAP properly and cleaning the device as recommended.

CPAP can only treat sleep disturbances such as snoring and sleep apnea. If you’re living with lung cancer and have trouble finding a comfortable sleeping position due to symptoms such as pain, night sweats, coughing, or breathlessness, be sure to let your doctor know. Good sleeping patterns can benefit your overall health, and your doctor may have recommendations to help you improve sleep with or without sleep medicine.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer. On MyLungCancerTeam, more than 13,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Do you have questions about CPAP and lung cancer? Have you used a CPAP machine for sleep apnea? Share your experience in the comments below, or start a conversation by posting on your Activities page.