Impact of cold and flu medication on obstructive sleep apnoea and its underlying traits: A pilot randomized controlled trial

Effects of the antipsychotic quetiapine on sleep and breathing: a review of clinical findings and potential mechanisms

Quetiapine is an antipsychotic medication indicated for schizophrenia and bipolar disorder. However, quetiapine also has hypnotic properties and as such is increasingly being prescribed at low doses 'off-label' in people with insomnia symptoms. Pharmacologically, in addition to its dopaminergic properties, quetiapine also modulates multiple other transmitter systems involved in sleep/wake modulation and potentially breathing. However, very little is known about the impact of quetiapine on obstructive sleep apnoea (OSA), OSA endotypes including chemosensitivity, and control of breathing. Given that many people with insomnia also have undiagnosed OSA, it is important to understand the effects of quetiapine on OSA and its mechanisms. Accordingly, this concise review covers the existing knowledge on the effects of quetiapine on sleep and breathing. Further, we highlight the pharmacodynamics of quetiapine and its potential to alter key OSA endotypes to provide potential mechanistic insight. Finally, an agenda for future research priorities is proposed to fill the current key knowledge gaps.

Pharmacotherapy for obstructive sleep apnea: targeting specific pathophysiological traits

INTRODUCTION

The pathophysiology of obstructive sleep apnea (OSA) is multi-factorial and complex. Varying OSA's pathophysiological traits have been identified, including pharyngeal collapsibility, upper airway muscle reactivity, arousal threshold, and regulation of the ventilatory drive. Being CPAP of difficult tolerance and other interventions reserved to specific subpopulations new pharmacological treatments for OSA might be resolutive.

AREAS COVERED

Several existing and newly developed pharmacological drugs can impact one or more endotypes and could therefore be proposed as treatment options for sleep disordered breathing. With this review we will explore different pathophysiological traits as new targets for OSA therapy. This review will summarize the most promising pharmacological treatment for OSA accordingly with their mechanisms of action on upper airway collapsibility, muscle responsiveness, arousal threshold, and loop gain.

EXPERT OPINION

Only understanding the pathophysiological traits causing OSA in each patient and placing the disease in the framework of patient comorbidities, we will be able to evolve interventions toward OSA. The development of new drug's combinations will permit different approaches and different choices beside conventional treatments. In the next future, we hope that sleep specialists will select the treatment for a specific patient on the base of its pathophysiology, defining a precision medicine for OSA.

New pharmacologic agents for obstructive sleep apnoea: what do we know and what can we expect?

PURPOSE OF REVIEW

This review provides a condensed description of pharmacological remedies explored in patients with obstructive sleep apnoea (OSA) as well as projections of what we might expect in terms of clinical performance of these drugs.

RECENT FINDINGS

Conventional drug therapies explored in OSA have generally produced disappointing results and there is a shortage of pharmacological treatment alternatives in this disorder. Recent insights into pathophysiological mechanisms potentially involved in OSA suggest that the condition may be divided into distinct subgroups based on clusters or defined by means of unique functional endotypic criteria. In fact, positive outcomes in clinical trials have now resulted in several drug candidates that show a convincing reduction of sleep disordered breathing in both short and intermediate term. Such drugs may be particularly useful in certain variants of OSA but not in others. These insights have also raised the ambition to create personalized therapies in OSA. Another recent development is the insight that OSA-linked conditions such as obesity, daytime somnolence and various forms of cardiovascular/metabolic disease may provide drug-based targets. For instance, pharmacological obesity therapy may provide not only positive metabolic effects but may also be a way to eliminate the anatomic component in obese OSA patients.

SUMMARY

Recent insights into the pathophysiology of OSA have opened possibilities to develop personalized therapy. Drugs addressing fundamental aspects of the sleep and breathing disorder provide a particularly promising avenue for development of novel forms of treatment in OSA.

Turning Over a New Leaf-Pharmacologic Therapy in Obstructive Sleep Apnea

Despite extensive research, there is currently no approved drug for obstructive sleep apnea (OSA) treatment. OSA is a heterogeneous condition that involves multiple dominating pathophysiological traits. Drug development in this field needs to address both pathophysiological mechanisms and associated comorbid conditions in order to meet requirements for long-term therapy in OSA. Several drug candidates have been proposed and ongoing phase II trials that target various forms of sleep-disordered breathing have been initiated. The field is moving toward tailored therapeutic approaches in patients with OSA.

Natural sleep endoscopy in obstructive sleep apnea: A systematic review

This study's objective is to systematically review the literature on natural sleep endoscopy (NSE), including the set-up, different scoring systems, visualized collapse patterns during natural sleep, additional measurements, and comparison of upper airway collapse between NSE and drug-induced sleep endoscopy (DISE). A computerized search on Medline, Web of Science and the Cochrane library was conducted, obtaining 39 hits. Ten prospective studies were included in which NSE was performed in adults with obstructive sleep apnea (OSA). This study's findings suggest the soft palate to be the most frequent site of obstruction (58.8 %), followed by the tongue base (43.2 %), lateral walls (29.9 %), and epiglottis (22.4 %), which is in line with previous findings during DISE. Based on this literature review, the authors conclude that at this stage high quality, comparative research between DISE and NSE is missing. To adequately compare findings between OSA patients, endoscopic classification of upper airway collapse should be standardized. Non-invasive predictive tools to determine pharyngeal collapse are currently under investigation and may obviate the need for invasive endoscopy. This review highlights the contribution of NSE in validating such novel diagnostic methods and in studying upper airway mechanics in a research setting, yet larger and adequately powered studies are needed.

Effects of hypnotics on obstructive sleep apnea endotypes and severity: Novel insights into pathophysiology and treatment

Impaired upper airway anatomy is the main cause of obstructive sleep apnea (OSA). However, there are other important non-anatomical contributors or "endotypes" including ventilatory control instability, poor pharyngeal dilator muscle responsiveness and waking up too easily to minor respiratory events (low arousal threshold). Recent studies have focused on the potential to target specific OSA causes with novel treatments to reduce OSA severity and improve efficacy with existing non-CPAP therapies which are often suboptimal (e.g., mandibular advancement splints). One novel target is pharmacotherapy with hypnotics to increase the threshold for arousal and reduce OSA severity in the approximately 30% of patients who have a low arousal threshold endotype. This increasing body of work has produced varied and at times unexpected findings which have challenged previous knowledge on the effects of hypnotics on upper airway physiology and breathing during sleep in people with OSA. This review provides a concise overview of the latest research that has investigated the effects of common hypnotics/sedative agents on upper airway physiology and OSA severity and potential implications for OSA pathophysiology, treatment and safety. This includes a summary of the latest knowledge on the effects of hypnotics on OSA endotypes. Priorities for future research are also highlighted.