Sleep Apnea and Obesity: Are They Related?

Current statistics indicate that 70% of U.S. citizens are medically classified as having overweight or obesity (NIH, 2017). Overweight is categorized as a body mass index (BMI) of 25 or greater, with obesity being a BMI of 30 or greater. Approximately one in three adults in the U.S. have obesity. Twenty-five million Americans, or one in five, are estimated to be affected by sleep apnea.

Define Sleep Apnea

Sleep apnea is defined, broadly, as the occurrence of five or more breathing-related events per hour, measured by polysomnography (sleep study). These events result in the momentary cessation of breathing or reduced breathing effectiveness.

Sleep Apnea Symptoms

The most notable sleep apnea symptoms include excessive daytime sleepiness and snoring. However you define it, sleep apnea is a serious breathing-related condition that is linked to many other medical disorders, including high blood pressure, heart attack, and stroke (Peppard, Young, & Barnett, 2013).

The prevalence of overweight and obesity have increased to epidemic proportions in the last few decades. This has resulted in increased occurrences of obesity-related disorders, such as sleep apnea. The three most important factors to consider with sleep apnea are sex, age group, and weight status. Sleep apnea occurs more frequently in men, older individuals, and those with higher BMIs (Peppard, et al, 2013).

Why Does Obesity Cause Sleep Apnea?

Excess body weight contributes to sleep apnea by causing increased pressure on upper airways, leading to collapse and decreased neuromuscular control from the fatty deposits. These fatty deposits contribute to decreased lung volume and make it more difficult to breathe (Young, Skatrud & Peppard, 2013). Neck circumference, waist circumference, and waist-to-hip ratio are also considerations when addressing overweight or obesity and suspecting sleep apnea. Neck circumference greater than 17 inches for men and 16 inches for women raise the risk of both obesity and sleep apnea. Waist measurements equal to or greater than 40 inches in men and 35 inches in women also raise the risk factor. Waist-to-hip ratio can also be calculated to assess for additional risk equivalent. This ratio is determined by dividing the waist measurement by the hip measurement. The greater this ratio, the more significant the risk factors for sleep apnea and other obesity-related disorders.

Treatment for Sleep Apnea

The most common treatment for sleep apnea is nighttime use of continuous positive airway pressure (CPAP). This option is often too burdensome for some patients for lifelong management of the disorder (Peppard et al, 2000). Others find the delivery of CPAP intolerable. In these patients, weight loss is a viable strategy for reduction in severity and progression of sleep apnea. Weight loss has been found to reduce the severity of sleep apnea as well as the development of the disorder. Overweight and obesity remain the most important modifiable causes of sleep apnea (Peppard et al, 2013).

By maintaining a healthy weight, one can potentially avoid sleep apnea and other obesity-related disorders. Reduction in weight by as little as 5-10% can potentially reduce the severity of sleep apnea that is already present and, in some cases, prevent its development.

Frequently Asked Questions

Can a FitBit or other fitness tracker detect sleep apnea?

While smart watches and fitness trackers with sleep apps are growing in popularity and sophistication, it is always advisable to talk to your healthcare provider if you think you may have sleep apnea. A sleep study in a sleep lab is still the most accurate way to diagnose sleep apnea. Some smart watches may have an internal sensor that records the wearer’s pulse wave, which is then used to calculate oxygen saturation and heart rate values. Newer devices, such as the FitBit Ionic, include an oxygen saturation sensor, which increases the accuracy of the data recorded. Smart watches and activity trackers can also detect movement during sleep, which can suggest the diagnosis of sleep apnea. As the technology becomes more advanced, these devices will likely be used more frequently to diagnose sleep apnea at home.

Can you treat sleep apnea with CPAP?

A Continuous Positive Airway Pressure (CPAP) machine is most commonly the first step in the treatment of sleep apnea. The CPAP machine has a pump, which provides a positive flow of air into the nasal passages to keep the airway open. The pump is connected by a hose to a nasal or face mask. Most people who use a CPAP machine feel immediate relief of symptoms, including increased energy, improved mood, and relief from morning headaches. In addition, a highly effective long-term treatment for sleep apnea is weight loss. Even a 10% weight loss can result in a 20% improvement in the severity of sleep apnea.