Impact of Sex on Sleep Disorders Across the Lifespan.

Sleep throughout a woman's life impacts her quality of life and medical comorbidities. The prevalence of sleep symptoms and disorders varies throughout a woman's life in association with the reproductive milestones of pregnancy and menopause. Studies have failed to identify a clear sex predominance of sleep disorders in childhood and adolescence. Sleep disturbances in pregnancy are common and may be associated with increased risk for adverse maternal outcomes. Menopause is associated with sleep disruption owing to increased rates of sleep-disordered breathing, development of insomnia owing to vasomotor symptoms and hormonal changes, circadian derangements, and changes in sleep architecture.

Identification of Sleep Medicine and Anesthesia Core Topics for Anesthesia Residency: A Modified Delphi Technique Survey.

BACKGROUND: Sleep disorders affect up to 25% of the general population and are associated with increased risk of adverse perioperative events. The key sleep medicine topics that are most important for the practice of anesthesiology have not been well-defined. The objective of this study was to determine the high-priority sleep medicine topics that should be included in the education of anesthesia residents based on the insight of experts in the fields of anesthesia and sleep medicine. METHODS: We conducted a prospective cross-sectional survey of experts in the fields of sleep medicine and anesthesia based on the Delphi technique to establish consensus on the sleep medicine topics that should be incorporated into anesthesia residency curricula. Consensus for inclusion of a topic was defined as >80% of all experts selecting "agree" or "strongly agree" on a 5-point Likert scale. Responses to the survey questions were analyzed with descriptive statistical methods and presented as percentages or weighted mean values with standard deviations (SD) for Likert scale data. RESULTS: The topics that were found to have 100% agreement among experts were the influence of opioids and anesthetics on control of breathing and upper airway obstruction; potential interactions of wake-promoting/hypnotic medications with anesthetic agents; effects of sleep and anesthesia on upper airway patency; and anesthetic management of sleep apnea. Less than 80% agreement was found for topics on the anesthetic implications of other sleep disorders and future pathways in sleep medicine and anesthesia. CONCLUSIONS: We identify key topics of sleep medicine that can be included in the future design of anesthesia residency training curricula.

Sex differences in obstructive sleep apnea phenotypes, the multi-ethnic study of atherosclerosis.

STUDY OBJECTIVES: The bases for sex disparities in obstructive sleep apnea (OSA), is poorly understood. We quantified the influences of event definitions, sleep-state, and body position on apnea-hypopnea indices (AHIs) in men and women, and evaluated sex differences in pathophysiological endotypes. METHODS: Polysomnography (PSG) data were analyzed from 2057 participants from the multi-ethnic study of atherosclerosis. Alternative AHIs were compared using various desaturation and arousal criteria. Endotypes (loop gain, airway collapsibility, arousal threshold) were derived using breath-by-breath analysis of PSG signals. Regression models estimated the extent to which endotypes explained sex differences in AHI. RESULTS: The sample (mean 68.5 ± 9.2 years) included 54% women. OSA (AHI4P ≥15/h, defined by events with ≥4% desaturations) was found in 41.1% men and 21.8% women. Compared to AHI4P, male/female AHI ratios decreased by 5%-10% when using 3%-desaturation and/or arousal criteria; p < 0.05. REM-OSA (REM-AHI ≥15/h) was similar in men and women regardless of event desaturation criteria. REM-AHI4P ≥15/h was observed in 57% of men and women each. In NREM, AHI4P in men was 2.49 (CI95: 2.25, 2.76) of that in women. Women demonstrated lower loop gain, less airway collapsibility, and lower arousal threshold in NREM (ps < 0.0005). Endotypes explained 30% of the relative sex differences in NREM-AHI4P. CONCLUSIONS: There are significant sex differences in NREM-AHI levels and in physiological endotypes. Physiological endotypes explained a significant portion of the relative sex differences in NREM-AHI. Definitions that use 4%-desaturation criteria under-estimate AHI in women. Combining NREM and REM events obscures OSA prevalence in REM in women.

Varying Hypopnea Definitions Affect Obstructive Sleep Apnea Severity Classification and Association With Cardiovascular Disease.

STUDY OBJECTIVES: To compare clinical features and cardiovascular risks in patients with obstructive sleep apnea (OSA) based on ≥ 3% desaturation or arousal, and ≥ 4% desaturation hypopnea criteria. METHODS: This is a cross-sectional analysis of 1,400 veterans who underwent polysomnography for suspected sleep-disordered breathing. Hypopneas were scored using ≥ 4% desaturation criteria per the American Academy of Sleep Medicine (AASM) 2007 guidelines, then re-scored using ≥ 3% desaturation or arousal criteria per AASM 2012 guidelines. The effect on OSA disease categorization by these two different definitions were compared and correlated with symptoms and cardiovascular associations using unadjusted and adjusted logistic regression. RESULTS: The application of the ≥ 3% desaturation or arousal definition of hypopnea captured an additional 175 OSA diagnoses (12.5%). This newly diagnosed OSA group (OSAnew) was symptomatic with daytime sleepiness similarly to those in whom OSA had been diagnosed based on ≥ 4% desaturation criteria (OSA4%). The OSAnew group was more obese and more likely to be male than those without OSA based on either criterion (No-OSA). However, the OSAnew group was younger, less obese, more likely female, and had a lesser smoking history compared to the OSA4% group. Those with any severity of OSA4% had an increased adjusted odds ratio for arrhythmias (odds ratio = 1.95 [95% confidence interval 1.37-2.78], P = .0155). The more inclusive hypopnea definition (ie, ≥ 3% desaturation or arousal) resulted in recategorization of OSA diagnosis and severity, and attenuated the increased odds ratio for arrhythmias observed in mild and moderate OSA4%. However, severe OSA based on ≥ 3% desaturation or arousals (OSA3%/Ar) remained a significant risk factor for arrhythmias. OSA based on any definition was not associated with ischemic heart disease or heart failure. CONCLUSIONS: The most current AASM criteria for hypopnea identify a unique group of patients who are sleepy, but who are not at increased risk for cardiovascular disease. Though the different hypopnea definitions result in recategorization of OSA severity, severe disease whether defined by ≥ 3% desaturation/arousals or ≥ 4% desaturation remains predictive of cardiac arrhythmias. COMMENTARY: A commentary on this article appears in this issue on page 1971.

Sleep in patients with restrictive lung disease.

Restrictive lung disease leads to ventilatory defects and diffusion impairments. These changes may contribute to abnormal nocturnal pathophysiology, including sleep architecture disruption and impaired ventilation and oxygenation. Patients with restrictive lung disease may suffer significant daytime fatigue and dysfunction. Hypercarbia and hypoxemia during sleep may impact progression of lung disease and related symptoms. Little is known about the impact of treatment of sleep disruption on sleep quality and overall prognosis in restrictive lung disease. This review discusses the pathophysiology of sleep and comorbid sleep disorders in restrictive lung diseases including interstitial lung disease, neuromuscular disease, and obesity hypoventilation syndrome.

Surgical treatment of obstructive sleep apnea: upper airway and maxillomandibular surgery.

Upper airway surgery is an important treatment option for patients with obstructive sleep apnea (OSA), particularly for those who have failed or cannot tolerate positive airway pressure therapy. Surgery aims to reduce anatomical upper airway obstruction in the nose, oropharynx, and hypopharynx. Procedures addressing nasal obstruction include septoplasty, turbinectomy, and radiofrequency ablation (RF) of the turbinates. Surgical procedures to reduce soft palate redundancy include uvulopalatopharyngoplasty, uvulopalatal flap, laser-assisted uvulopalatoplasty, and RF of the soft palate with adenotonsillectomy. More significant, however, particularly in cases of severe OSA, is hypopharyngeal or retrolingual obstruction related to an enlarged tongue, or more commonly due to maxillomandibular deficiency. Surgeries in these cases are aimed at reducing the bulk of the tongue base or providing more space for the tongue in the oropharynx so as to limit posterior collapse during sleep. These procedures include genioglossal advancement, hyoid suspension, distraction osteogenesis, tongue RF, lingualplasty, and maxillomandibular advancement. Successful surgery depends on proper patient selection, proper procedure selection, and experience of the surgeon. Most surgeries are done in combination and in a multistep manner, with maxillomandibular advancement typically being reserved for refractory or severe OSA, or for those with obvious and significant maxillomandibular deficiency. Although not without risks and not as predictable as positive airway pressure therapy, surgery remains an important therapeutic consideration in all patients with OSA. Current research aims to optimize the success of these procedures by identifying proper candidates for surgery, as well as to develop new invasive procedures for OSA treatment.