Positional Obstructive Sleep Apnea (POSA)

1. What Is Positional Obstructive Sleep Apnea (POSA)?

Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) is characterized by partial (hypopneas) or complete (apneas) obstruction of the upper airway multiple times during sleep. These events cause oxygen desaturation and micro-arousals that typically go unnoticed by the sleeper. As a result, sleep is significantly disrupted and of poor quality.

Several factors can cause or worsen OSAHS, including age, obesity, excessive alcohol or tobacco use, and the intake of sedatives. ENT abnormalities—such as an enlarged tongue, nasal obstruction, or large tonsils—are also risk factors.

In some individuals, obstructive apneas worsen when lying on the back. This is due to gravity pulling the tongue and/or lower jaw backward, narrowing the upper airway.

Positional OSAHS is diagnosed when more than 50% of apnea events occur in the supine (back) position. If apneas only occur in this position, it is considered exclusive positional OSAHS. Among those diagnosed with OSAHS, over half have positional OSAHS, and about one-third have the exclusive form.

2. Positional Therapy

OSAHS is most commonly treated with Continuous Positive Airway Pressure (CPAP), especially in moderate to severe cases. For positional sleep apnea, there are specific positional therapy solutions that help prevent sleeping on the back.

The traditional method involves placing an object behind the back—such as a tennis ball or a pillow-filled backpack—to encourage side sleeping. Though not always comfortable and potentially harmful to the spine, this setup helps prevent supine-related apneas.

The Ronfless Belt, available on our website, is a patented medical device designed to help users avoid sleeping on their back. Worn under the arms (and beneath the chest for women), it features a semi-rigid half-ball positioned against the back. The belt has been shown to reduce back-sleeping time by over 79%, significantly decreasing snoring and supine apneas. After several nights of consistent use, and once side sleeping becomes habitual, the belt may no longer be necessary.

A more advanced option is the smart positional therapy belt. This device includes a sensor that detects at-risk sleeping positions. When the user turns onto their back, the sensor emits gentle vibrations that prompt a subconscious repositioning to the side. The belt is soft, comfortable, and worn around the torso.

There are also positional pillows, ergonomically designed to maintain side sleeping. These pillows help angle the head slightly downward, pushing the tongue and jaw forward to open the pharynx, support proper airflow, and reduce snoring and apneas. Positional pillows are ideal for individuals with mild AHI and can be used in combination with CPAP therapy.

Conclusion

Studies* have confirmed the effectiveness of positional therapy in treating exclusive positional OSAHS, especially in mild to moderate cases. While not as effective as CPAP, positional therapy can significantly reduce the AHI when used in conjunction with CPAP. Nonetheless, CPAP remains the gold standard treatment for OSAHS.

It is also worth noting that positional therapy can be an effective solution for snorers who sleep on their back.

You can find our range of positional and anti-snoring devices in the Anti-Snoring section of our website.