Sleep apnea is when sufferer stops breathing (apnea) at night as the muscles in the throat relax and then resumes when brain semi-awakes when the oxygen supply gets low to restore respiration. This happens tens to hundreds of times at night and can be debilitating when the disruption to sleep causes other health effects such as fatigue and tiredness.
There are 3 major types of Sleep Apnea – the least common is central sleep apnea which is centrally regulated and arises from the lack of signal from the brain to the muscles in the throat. The most common is obstructive sleep apnea which affects about 30% US adults but it remains undiagnosed in a majority of people. The way it is diagnosed is by polysomnography which measures brain EEG, sleep stages, respiration and oxygen saturation in a lab setting.
There have been other ways that diagnosis has been addressed. For example, apple smart watch got an approval from FDA (https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K240929) and there have been other ways that it has been diagnosed.
Sleep Apnea is measured with a Apnea-Hypoapnea index, which is the number of apneas or hypoapneas recorded via polysomnography per hour of sleep. Apnea is defined as cessation (90%+) of airflow lasting at least 10 seconds, hypoapnea as a decrease in airflow by at least 30% from baserise for at least 10 seconds occuring with a drop in oxygen saturation (Sp)2) by at least 4% or a brief awakening. The severity scale is measured by Normal (<5 events/hr), Mild (5-14 events/hr), Moderate (15-29 events/hr), and Severe (>30 events/hr). Other scales such as oxygen desaturation index, respiratory disturbance index are also used.
The treatment for sleep apnea has been mostly Continuous positive airway pressure(CPAP) which is tho mosts common and reliable method though many do not find it comfortable and rather cumbersome. However, nearly 50% of new user stop using the CPAP due to discomfort. (https://pmc.ncbi.nlm.nih.gov/articles/PMC7137251/) Other similar devices that help are called bilevel positive airway pressure (BPAP) which provide more pressure when you inhale but less when you exhale. Then there are some oral appliances that have an effect by keeping the airway open physically. In addition, there are myofunctional therapies that strengthen upper airway muscles to reduce narrowing. There are other surgical options such as tissue ablation, maxillomandibular advancement, nerve stimulation, and more invasive tracheostomy.
New drug from Apnimed combines Aroxybutynin, a antimuscarinic and atomoxetine, a noradrenaline reuptake inhibitor to enhance the neuromuscular tone in critical muscles. These hypoglossal nerve originates from the hypoglossal motor nucleus and in the synapses The aroxybutynin blocks the muscarinic receptor and atomexetine stops the norephinephrine transporter from going taking norepinephrine back and increasing the probability of binding to adrenergic receptors. This work has been published (https://pmc.ncbi.nlm.nih.gov/articles/PMC10765395/) and Phase 3 studies LunAIRo and SynAIRgy (https://clinicaltrials.gov/study/NCT05813275) are in progress.
Individual patient data can be seen in this paper link
