Smartphones to evaluate sleep disorders while awake

A new smartphone system developed by scientists can diagnose sleep disorders while a person is awake, a breakthrough may be more convenient, inexpensive way to detect obstructive sleep apnea.
According to the American Sleep Apnea Association, it is estimated that 22 million Americans suffer from the malady, with 80 per cent of moderate to severe obstructive sleep apnea (OSA) cases undiagnosed.
"We have developed technology that could help diagnose OSA and sleep disorders in a convenient way," said Yaniv Zigel from Ben-Gurion University of the Negev (BGU) in Israel.
"The audio-analysis application can record speech signals from awake subjects. Now, we will be able to get a fast, OSA severity estimation without an overnight sleep study," said Zigel.

Currently, patients are diagnosed using polysomnography (PSG) to record brain waves, blood oxygen level, heart rate, breathing and eye and leg movements overnight.
The new system, which does not require contact sensors, can be installed onto a smartphone or other device that utilises ambient microphones.

It both analyses speech while the user is awake and records and evaluates overnight breathing sounds using new technology that is simpler to use and significantly less expensive than PSG.
"All sleep studies conducted in laboratory or at-home settings currently require subjects to be connected to numerous electrodes and sensors," said Eliran Dafna from BGU.

"Processing the data on sleep-wake states and corresponding aspects of physiology is time-consuming, tedious and costly because of its complexity and the need for technical expertise. The market is begging for a better solution," said Dafna.
Researchers have tested the new speech and breathing sound analysis systems on more than 350 subjects, along with PSG, in laboratory and at-home settings.
They were able to reliably evaluate sleep quality parameters such as sleep-wake activity, snoring severity and OSA using this system.
"We are excited about this non-contact sleep tracking system, which does not require patients to wear uncomfortable monitoring equipment on their body," said Ariel Tarasiuk from Soroka Medical Centre in Israel.

"This application can also be very useful for continuous positive airway pressure (CPAP) machine users who want to check the effectiveness of their sleep apnea therapy," said Tarasiuk.
Devices incorporating the speech-analysis system may be portable or stationary and could be available also in public locations or clinics.