Obesity and sleep apnea

Obesity and Sleep Apnea: How They Affect Each Other

Obesity and sleep apnea are two health conditions that often occur together and can exacerbate each other. In this blog post, we’ll discuss the statistics and causes of both conditions, as well as how they affect each other.

What is Obesity?

Obesity is often defined by body mass index (BMI). An adult's BMI is calculated by dividing weight in kilograms by height in meters squared. The resulting value falls into one of the following categories:

- Underweight: 18.5 and lower
- Healthy weight: between 18.5 and 24.9
- Overweight: between 25 and 29.9
- Obesity: between 30 and 39.9
- Severe obesity: 40 or more

Keep in mind that BMI is just one measure of health. For example, if you have a lot of muscle, you can be overweight without having a lot of body fat. BMI values ​​can also vary between people of different ethnic backgrounds and are measured differently in children. Talk to your doctor if you are concerned about your weight; they can use other measurements, such as waist circumference, to determine if your weight poses a health risk.

How Many People Are Overweight or Obese?

Worldwide, nearly 10% of adults are obese – that’s almost one in 10 people. When it comes to overweight, the numbers are even higher: almost one in three adults has a BMI between 25 and 29.9. So if you’re heavier than you’d like to be, you’re certainly not alone.

How Many Overweight People Have Sleep Apnea?

In the general population, it is thought that around 25% have sleep apnea. However, it is estimated that over 80% of cases worldwide remain undiagnosed, making exact figures difficult to determine. What we do know is that around 40% of overweight people have sleep apnea. In people who are severely obese, this figure rises to 77%.

What Causes Sleep Apnea?

The most common form of sleep apnea is obstructive sleep apnea (OSA). This sleep disorder occurs when the upper airway (in the nose and throat) becomes blocked during sleep, often resulting in loud snoring. When this happens, your breathing may stop for periods of 10 seconds or longer, called apneas. These apneas cause you to wake up briefly to gasp for air before falling back asleep. This can happen hundreds of times a night without you realizing it. Common symptoms include feeling tired in the morning and excessive daytime sleepiness, even after a full night's sleep.

Other symptoms of OSA include:

- Memory problems
- Headache in the morning
- Depressive feelings
- Night sweats
- Decreased libido
- Frequent nocturnal urination
- Weight gain

Does Sleep Apnea Cause Weight Gain?

Weight gain can be a symptom of OSA. This can happen for a few reasons. First, if you’re feeling exhausted from less sleep, you’ll likely have little energy or desire to exercise. Lack of quality sleep can also disrupt hormone levels, including those that control appetite, making you want to eat more. And when we’re tired or down, we’re more likely to reach for sugary snacks and comfort foods for an energy boost.

How Does Obesity Affect Sleep Apnea?

With obstructive sleep apnea, it’s all about what’s blocking the airway. In most cases, this is the muscles and soft tissues of the throat, which relax during sleep. If someone has nasal congestion, a naturally narrower airway, or other physical characteristics such as a large tongue or large tonsils, the airway can become more easily blocked. It’s easy to see how being overweight or obese can make this worse: weight gain increases the amount of fatty tissue, including around the throat area, which narrows the airway, especially when you’re lying down. Overweight people are also more likely to have a larger neck circumference, which is a risk factor for OSA.

Weight can also affect the severity of OSA, which is divided into three categories:

- Mild: 5 to 14 apneas per hour
- Moderate: 15 to 30 apneas per hour
- Severe: more than 30 apneas per hour

In general, the higher your BMI, the more severe your sleep apnea. People with a BMI under 30 tend to have less severe OSA, but they still need treatment because they are four times more likely to have high blood pressure than people in the obese category who do not have OSA.

Other Forms of Sleep Apnea and Obesity

Although obstructive sleep apnea accounts for 84% of sleep apnea cases, there are other forms that are less common:

- Central sleep apnea: this is when the brain stops sending signals to the muscles that control breathing during sleep, causing breathing to stop briefly. This has nothing to do with blocking the airways; they remain open during sleep.
- Mixed sleep apnea: As the name suggests, this is a combination of central and obstructive sleep apnea.

Both conditions are primarily caused by medical conditions affecting the brain, and thus are not associated with obesity.

Is Obesity the Only Risk Factor for Sleep Apnea?

Although obesity is a risk factor for OSA, it is certainly not the only one. Other risk factors include:

- Male gender
- A family history of sleep apnea
- Age (especially over 55 years)
- The use of certain tranquilizers
- Alcohol consumption (especially before going to bed)
- Smoking

Women and Sleep Apnea

Although male gender is a risk factor for sleep apnea, some studies suggest that up to half of women between the ages of 20 and 70 may have the condition. As with men, weight can play a role. Weight gain is one of the sleep apnea symptoms that is more common in women than in men. In addition, OSA is more common in postmenopausal women, which may be explained by the tendency of women to gain weight after menopause.

Conclusion
In summary, obesity and sleep apnea are closely linked and can negatively impact each other. By being aware of these risks and striving for a healthy weight and lifestyle, you can reduce your risk of both conditions and achieve a better quality of life.