COPD Plus Sleep Apnea (Overlap Syndrome): Why Treating Both Matters

When COPD and sleep apnea occur together, it is called overlap syndrome. It carries higher risks than either condition alone. In long-term studies, people with overlap syndrome who did not use CPAP had higher death rates and more hospital stays for COPD flare-ups than those who did.¹ These studies were not randomized, so the results call for some caution. But they support testing and treating sleep apnea in people with COPD.²

What is overlap syndrome?

COPD (chronic obstructive pulmonary disease) is a long-term lung disease that makes it hard to move air out of the lungs. It includes emphysema and chronic bronchitis. Obstructive sleep apnea (OSA) is a different problem. During sleep, the airway in the throat narrows or closes many times, causing pauses or shallow breathing.

Doctors measure sleep apnea with a sleep study. The main result is the AHI (apnea-hypopnea index). It is the average number of breathing pauses or shallow breaths per hour of sleep.

When a person has both, it is called overlap syndrome. Both conditions affect breathing. People with overlap syndrome are more likely to develop pulmonary hypertension than people with either condition alone. This is high blood pressure in the blood vessels of the lungs.¹

Why does overlap syndrome raise health risks?

A long-term study followed 651 people for a median of about 9.4 years. It compared three groups. None had heart failure, heart attack, or stroke at the start.¹

• Group 1 — people with overlap syndrome using CPAP
• Group 2 — people with overlap syndrome not using CPAP
• Group 3 — people with COPD alone

The researchers accounted for age, weight, smoking, COPD severity, sleep apnea severity, and other factors. People with untreated overlap syndrome had:

• Higher risk of death — a 79% higher risk than people with COPD alone
• More hospital stays — a 70% higher risk of being hospitalized for a severe COPD flare-up

People with overlap syndrome who used CPAP did not have this extra risk. Their outcomes were similar to people who had COPD alone.¹

Does CPAP help people with COPD and sleep apnea?

CPAP (continuous positive airway pressure) is a small bedside machine. It gently blows air through a mask to keep the throat open during sleep. The research points toward real benefits.

• Records study — Another study looked at the records of 227 people with overlap syndrome. More hours of CPAP use each night were linked to a lower risk of death, even after accounting for age. Older age was linked to a higher risk of death. People who used CPAP less than two hours a night tended to be older than those who used it more.³
• 2023 review — This review gathered the five studies that met its standards. Together, they found that CPAP was linked to fewer COPD flare-ups, fewer COPD-related hospital stays, and lower death rates in overlap syndrome.²

How strong is the evidence?

The results are consistent, but they come from observational studies, not randomized trials. People were not randomly assigned to use CPAP or not. So other differences between groups may explain some of the benefit.

The 2023 review also noted that the studies defined COPD, sleep apnea, and CPAP use in different ways. Its authors called for more research with standard definitions.² Even so, the pattern across studies is the same. People with overlap syndrome who use CPAP tend to do better, and more use is linked to better results.¹³²

Does how much I use CPAP matter?

It appears to. In that records study, survival was linked to the number of hours of CPAP use, not just to owning a machine.³ Wearing it for most of the night, every night, gives treatment the best chance to help.

If the mask is uncomfortable or the pressure feels wrong, tell your sleep team. These problems can often be adjusted.

When should you get checked?

If you have COPD, ask about a sleep evaluation if you:

• Snoring or gasping — Snore loudly, or someone has seen you stop breathing or gasp during sleep
• Morning symptoms — Wake up with morning headaches or feel unrefreshed
• Daytime sleepiness — Feel very sleepy or tired during the day
• Flare-ups — Have had frequent COPD flare-ups or hospital stays
• Lung pressure — Have been told you have high blood pressure in your lungs

Overlap syndrome carries higher risks. So finding and treating sleep apnea may be an important part of caring for your COPD.¹

How Universal Sleep Solutions can help

At Universal Sleep Solutions we offer in-lab and home sleep testing, and we will help decide which test fits your health needs. If you have overlap syndrome, we set up CPAP or BiPAP therapy and provide ongoing follow-up to help you use it comfortably.