Nerve stimulation for the treatment of obstructive sleep apnea

Exploring hypoglossal nerve stimulation therapy for obstructive sleep apnea: A comprehensive review of clinical and physiological upper airway outcomes

Obstructive sleep apnea (OSA) is a chronic disorder characterized by recurrent episodes of upper airway collapse during sleep, which can lead to serious health issues like cardiovascular disease and neurocognitive impairments. While positive airway pressure serves as the standard treatment, intolerance in some individuals necessitates exploration of alternative therapies. Hypoglossal nerve stimulation (HGNS) promises to mitigate OSA morbidity by stimulating the tongue muscles to maintain airway patency. However, its effectiveness varies, prompting research for optimization. This review summarizes the effects of HGNS on upper airway obstruction from human and animal studies. It examines physiological responses including critical closing pressure, maximal airflow, nasal and upper airway resistance, compliance, stiffness, and geometry. Interactions among these parameters and discrepant findings in animal and human studies are explored. Additionally, the review summarizes the impact of HGNS on established OSA metrics, such as the apnea-hypopnea index, oxygen desaturation index, and sleep arousals. Various therapeutic modalities, including selective unilateral or bilateral HGNS, targeted unilateral HGNS, and whole unilateral or bilateral HGNS, are discussed. This review consolidates our understanding of HGNS mechanisms, fostering exploration of under-investigated outcomes and approaches to drive advancements in HGNS therapy.

Transcutaneous electrical stimulation in obstructive sleep apnoea: current developments and concepts of the TESLA-home programme

PURPOSE OF REVIEW

Obstructive sleep apnoea (OSA) is a highly prevalent condition affecting about 1 billion people worldwide. The first line therapy for most patients with OSA is continuous positive airway pressure (CPAP) therapy. However, there are significant limitations with long-term adherence to CPAP therapy, which may be as low as 30-60%.

RECENT FINDING

Electrical stimulation of the hypoglossal nerve has been studied in recent years. It achieves upper airway patency by causing a contraction of the genioglossus muscle, the strongest dilator of the upper airway, and by maintaining its neuromuscular tone in the asleep patient with OSA. Electrical stimulation can be delivered invasively, hypoglossal nerve stimulation (HNS), and noninvasively, transcutaneous electrical stimulation in OSA (TESLA). However, randomised controlled trials, the STAR and the TESLA trial, have provided promising results on efficacy and safety of the methods.

SUMMARY

Patient and public involvement underlines the interest in TESLA and HNS and highlights the need to provide non-CPAP therapeutic options to those who may find it difficult to cope with first line therapies. The relatively low costs and the favourable safety profile of the TESLA approach provide the chance to offer this treatment to patients with OSA following further development of the evidence.

All You Need Is Sleep: the Effects of Sleep Apnea and Treatment Benefits in the Heart Failure Patient

PURPOSE OF REVIEW

Recognition and treatment of sleep apnea is an important but easily overlooked aspect of care in the heart failure patient. This review summarizes the data behind the recommendations in current practice guidelines and highlights recent developments in treatment options.

RECENT FINDINGS

Neuromodulation using hypoglossal nerve stimulation has been increasingly used for treatment of OSA; however, it has not been studied in the heart failure population. Alternatively, phrenic nerve stimulation for treatment of CSA is effective for heart failure patients, and cardiac resynchronization therapy can be effective in improving CSA in pacing-induced cardiomyopathy. In patients suspected to have sleep apnea, polysomnography is recommended to better understand the prognosis and treatment options. Positive airway pressure is the standard treatment for sleep apnea; however, neurostimulation can be especially effective in those with predominantly central events. Understanding the pathophysiology of sleep apnea can guide further management decisions.

Association Between Conflict of Interest and Published Position on Hypoglossal Nerve Stimulation for Sleep Apnea

OBJECTIVE

To determine if there is an association between authors' financial conflict of interest and published position on clinical use of hypoglossal nerve stimulation for obstructive sleep apnea.

STUDY DESIGN

Retrospective cross-sectional analysis.

SETTING

International roster of authors and articles analyzed.

METHODS

A Google Scholar search was performed for editorials and reviews citing the 2014 New England Journal of Medicine article on hypoglossal nerve stimulation for obstructive sleep apnea. Included articles were coded as favorable or neutral. Conflict of interest was recorded as declared by the authors in these articles and as independently searched in the Open Payments registry.

RESULTS

Sixteen articles from 45 independent authors were analyzed. Nine articles by authors were coded as favorable. Among authors of articles with favorable views, 16 (59%) had a financial conflict of interest with the manufacturer of the hypoglossal nerve stimulator device, as opposed to only 1 of 21 (5%) authors of neutral/unfavorable articles. When we included only authors to whom payments could be identified or excluded on Open Payments, 16 of 20 (80%; 95% CI, 62%-98%) authors of favorable articles had a financial conflict, while 1 of 10 (10%; 95% CI, 0%-29.6%) of neutral/unfavorable articles did (P = .004).

CONCLUSION

Our study demonstrates an association between published position on hypoglossal nerve stimulator use and financial conflict with the device manufacturer. Several undeclared conflicts were also found, suggesting a role for independent search for conflicts during the review process.