On the cutting edge of obstructive sleep apnoea: where next?

Abstract

Obstructive sleep apnoea is a common disease that is now more widely recognised because of the rise in prevalence and the increasingly compelling data that shows major neurocognitive and cardiovascular sequelae. At the same time, the clinical practice of sleep medicine is changing rapidly, with novel diagnostics and treatments that have established a home-based (rather than laboratory-based) management approach. We review the most recent insights and discoveries in obstructive sleep apnoea, with a focus on diagnostics and therapeutics. As will be discussed, management of obstructive sleep apnoea could soon transition from a so-called one size fits all approach to an individualised approach.

Figure 1. Risk factors, pathogenic mechanisms, and treatments for obstructive sleep apnoea

Risk factors for obstructive sleep apnoea have long been recognised, but novel pathogenic mechanisms have now been detected in patients with the disorder. Although CPAP is the current treatment of choice irrespective of underlying cause, treatments based on tackling individual pathogenic mechanisms might prove a successful alternative approach in the future. CPAP=continuous positive airway pressure. MAD=mandibular advancement device. UPPP=uvulopalatopharyngoplasty. HGNS=hypoglossal nerve stimulation. Figure adapted from Jordan and colleagues, by permission of Elsevier.

Figure 2. Polysomnography during hypoglossal nerve stimulation

Initially, hypoglossal nerve stimulation is off, with periods of obstructive apnoea accompanied by oxygen desaturation and arousal. Stimulation is then turned on at a level above the capture threshold, in this example at 2·5 mA. Regular impulses can be seen in the electromyography. Improvement is noted in flow characteristics such that desaturation and arousal are no longer present, however, flow limitation remains. Variable response to hypoglossal nerve stimulation between patients emphasises the importance of refining patient selection. By permission of Inspire Medical Systems.