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Before and After CPAP Machine Effects: How Your Body Changes


Written by Afy Okoye

Reviewed by Dr. Michael Breus

Our Editorial Process

Table of Contents

For people with obstructive sleep apnea (OSA), the difference before and after continuous positive airway pressure (CPAP) therapy can be significant. When used consistently, a CPAP machine can offer benefits like better sleep, enhanced productivity, and reduced long-term health risks. 

CPAP therapy is one of the most effective treatments for OSA, which involves repeated breathing interruptions during sleep. By delivering air through a mask and into the airway, a CPAP device can stabilize breathing and improve overall health.

Impacts of Sleep Apnea Before Treatment

Before treatment, OSA can impact sleep and everyday health. OSA involves recurring pauses in breathing that trigger short awakenings throughout the night. When left untreated, disrupted breathing and fragmented sleep can cause numerous short-term symptoms, including: 

  • Loud snoring
  • Gasping or choking during sleep
  • Excessive daytime sleepiness and a tendency to doze off at inappropriate times 
  • Impaired focus, memory, and other elements of thinking 
  • Morning headaches 
  • Frequent urination at night 
  • Elevated risk of accidents, including when driving or working 

Long-Term Risks of Sleep Apnea

In addition to its immediate effects, untreated OSA heightens the risk of a number of serious medical conditions and overall mortality. 

By interfering with normal processes of sleep and lowering oxygen levels in the body, sleep apnea can lead to cardiovascular problems. For example, untreated OSA is linked with a greater risk of high blood pressure, stroke, heart attack, and heart disease. 

OSA can negatively affect how the body manages blood sugar, making it more likely for people with untreated OSA to develop type 2 diabetes. OSA increases the risk of liver disease and has been associated with acid reflux, asthma and lung problems, and kidney disease.

Other Potential Effects After Using CPAP

CPAP therapy can reduce the symptoms of OSA, improve quality of life, and decrease the chances of long-term health complications. With consistent use, a CPAP can have many potential positive effects.

Sounder Sleep

A CPAP keeps breathing steady during sleep, which minimizes interruptions and makes it easier to wake up well-rested. For most people, sleep improves almost immediately after starting CPAP therapy, and healthier sleep patterns develop within the first week.

Reduced Snoring

Very loud and frequent snoring is common in people with OSA, and CPAP therapy is calibrated to resolve this bothersome symptom.

Greater Daytime Energy and Focus

By reducing sleep fragmentation, CPAP therapy can boost daytime alertness. Using a CPAP supports better concentration, clearer thinking, and improved productivity. 

Lower Risk of Accidents

People with untreated OSA are at least twice as likely to have a car crash related to drowsy driving. After CPAP treatment, alertness improves, and the risk of accidents decreases.

Improved Sleep For a Bed Partner

Nightly use of a CPAP can improve the sleep of a bed partner since they can avoid disruptions from a person who OSA snoring or tossing and turning in bed. 

Enhanced Mental Health

People with OSA who use a CPAP report having a better mood and fewer symptoms of depression. Using a CPAP enables better sleep, which has a close connection with mental health. 

Better Cardiovascular Health

By treating OSA, CPAP machines can promote cardiovascular health, including better control of blood pressure. While the exact impact of CPAP therapy on the likelihood of heart attack and stroke is not clear, growing evidence points to a reduced risk when a CPAP is used consistently. 

Better Metabolic Health

OSA makes it harder for the body to regulate blood sugar levels, and CPAP therapy can help address this problem and support metabolic health.

Reduced Risk of Other Health Problems

Studies have found that regular use of a CPAP for OSA can potentially deliver other benefits, including: 

  • Lower risk of erectile dysfunction 
  • Decreased acid reflux 
  • Reduced symptoms of asthma

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Getting Started With CPAP Treatment

Your doctor or a sleep specialist will help you get started with CPAP therapy. They will provide a CPAP device and accessories, including a CPAP mask. The CPAP comes with settings that are designed to prevent breathing interruptions at night. 

It is normal to encounter challenges in adjusting to using a CPAP when you first get started. Certain tips may help you stick with CPAP therapy: 

  • Acclimate faster by by using the device as much as possible
  • Focus on the positives of treatment, including better sleep
  • Practice using the CPAP while you’re awake and doing other activities, like watching TV

When To Talk To Your Doctor About Side Effects

To make it easier to get the most from CPAP therapy, talk with your doctor if you have any side effects that impact your ability to continue using your CPAP. Being proactive enables earlier troubleshooting, which may involve your doctor making simple adjustments to your mask or pressure settings that can dramatically improve the comfort and success of CPAP therapy.

About The Author

Afy Okoye

Staff Writer, Sleep Health

Afy is a writer and creative strategist in San Francisco with a master’s degree in international health policy from the London School of Economics. She has written for VeryWell Health,, and Paste magazine and edited peer-reviewed journal manuscripts for Elsevier. Afy says her work with The Sleep Doctor is anything but “sleepy.” She enjoys the opportunity to learn new information and share knowledge that gives people the power to make better choices. Afy also likes to read non-fiction, do creative writing, and travel solo.

  • POSITION: Side Sleeper
  • TEMPERATURE: Hot Sleeper

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