The efficacy of surgery for upper airway resistance syndrome: A systematic review, meta-analysis and case series

PURPOSE

Upper airway resistance syndrome (UARS) is a sleep related breathing disorder that was first described in 1993. This goal of this study is to determine the efficacy of surgical intervention for UARS.

MATERIALS AND METHODS

Systematic review of the literature and a case series of UARS patients at a large integrated healthcare system. Meta-analysis was performed.

RESULTS

For the systematic review, 971 abstracts were reviewed and 3 articles were included, yielding 49 subjects. All of the included studies were of level 3 or 4 evidence. Significant improvement in Epworth Sleepiness Scale (ESS) score was noted after surgery in two level 4 studies. No significant change in ESS was noted in one level 3 study. Our retrospective chart review of eleven UARS patients compared preoperative and postoperative ESS scores, as well as sleep study data. Patients underwent a variety of surgical procedures. Our findings show a significant improvement in mean ESS scores after surgery, from 11.0 (±3.5) to 7.0 (±4.8) with p = 0.01, though no difference in apnea hypopnea index (AHI) and respiratory disturbance index (RDI) were identified. Meta-analysis was performed on 2 studies from the systematic review and our cases series data. UARS surgery showed a mean change in ESS of -5.89 (95% CI, -8.29 to -3.50).

CONCLUSIONS

This systematic review, meta-analysis and retrospective case series indicate that surgery may improve ESS scores in patients with UARS. AHI and RDI are unlikely to be impacted by surgery.

Prospective Randomized Controlled Trial on the Efficacy of Continuous Positive Airway Pressure and Adaptive Servo-Ventilation in the Treatment of Chronic Complex Insomnia

BACKGROUND

Complex insomnia, the comorbidity of chronic insomnia and obstructive sleep apnea (OSA), is a common sleep disorder, but the OSA component, whether presenting overtly or covertly, often goes unsuspected and undiagnosed due to a low index of suspicion. Among complex insomniacs, preliminary evidence demonstrates standard CPAP decreases insomnia severity. However, CPAP causes expiratory pressure intolerance or iatrogenic central apneas that may diminish its use. An advanced PAP mode-adaptive servo-ventilation (ASV)-may alleviate CPAP side-effects and yield superior outcomes.

METHODS

In a single-site protocol investigating covert complex insomnia (ClinicalTrials.gov identifier: NCT02365064), a low index of suspicion for this comorbidity was confirmed by exclusion of 455 of 660 eligible patients who presented during the study period with overt OSA signs and symptoms. Ultimately, stringent inclusion/exclusion criteria to test efficacy yielded 40 adult, covert complex insomnia patients [average Insomnia Severity Index (ISI) moderate-severe 19.30 (95% CI 18.42-20.17)] who reported no definitive OSA symptoms or risks and who failed behavioral or drug therapy for an average of one decade. All 40 were diagnosed with OSA and randomized (using block randomization) to a single-blind, prospective protocol, comparing CPAP (n = 21) and ASV (n = 19). Three successive PAP titrations fine-tuned pressure settings, facilitated greater PAP use, and collected objective sleep and breathing data. Patients received 14 weeks of treatment including intensive biweekly coaching and follow-up to foster regular PAP use in order to accurately measure efficaciousness. Primary outcomes measured insomnia severity and sleep quality. Secondary outcomes measured daytime impact: OSA-induced impairment, fatigue severity, insomnia impairment, and quality of life. Performance on these seven variables was assessed using repeated measures ANCOVA to account for the multiple biweekly time points.

FINDINGS

At intake, OSA diagnosis and OSA as a cause for insomnia were denied by all 40 patients, yet PAP significantly decreased insomnia severity scores (p = 0.021 in the primary ANCOVA analysis). To quantify effect sizes, mean intake vs endpoint analysis was conducted with ASV yielding nearly twice the effects of CPAP [- 13.2 (10.7-15.7), Hedges' g = 2.50 vs - 9.3 (6.3-12.3), g = 1.39], and between mode effect size was in the medium-large range 0.65. Clinically, ASV led to remission (ISI < 8) in 68% of cases compared to 24% on CPAP [Fisher's exact p = 0.010]. Two sleep quality measures in the ANCOVA analysis again demonstrated superior significant effects for ASV compared to CPAP (both p < 0.03), and pre- and post-analysis demonstrated substantial effects for both scales [ASV (g = 1.42; g = 1.81) over CPAP (g = 1.04; g = 0.75)] with medium size effects between modes (0.54, 0.51). Measures of impairment, residual objective sleep breathing events, and normalized breathing periods consistently demonstrated larger beneficial effects for ASV over CPAP.

INTERPRETATION

PAP therapy was highly efficacious in decreasing insomnia severity in chronic insomnia patients with previously undiagnosed co-morbid OSA. ASV proved superior to CPAP in this first efficacy trial to compare advanced to traditional PAP modes in complex insomnia. Future research must determine the following: pathophysiological mechanisms to explain how OSA causes chronic insomnia; general population prevalence of this comorbidity; and, cost-effectiveness of ASV therapy in complex insomnia. Last, efforts to raise awareness of complex insomnia are urgently needed as patients and providers appear to disregard both overt and covert signs and symptoms of OSA in the assessment of chronic insomnia.

Upper airway resistance syndrome 2018: non-hypoxic sleep-disordered breathing

INTRODUCTION

Upper airway resistance syndrome (UARS) as obstructive sleep apnea syndrome (OSAS) has been described as abnormal breathing during sleep, based on the recording technologies and knowledge of the time. These terms have advanced the field, but are they still useful? Area Covered: Historically, the definition of UARS syndrome was aimed at recognizing pathology not covered by 'OSAS' and to prompt specialists to go further than the obvious. It aimed at pushing specialists to recognize pathologies earlier and to elicit research in the developmental features of sleep-disordered-breathing (SDB). The technology used to monitor SDB changed over-time, allowing recognition of SDB differently but not necessarily better. Expert Commentary: Currently, we have a better understanding of the development of SDB, and its evolution with aging, leading to co-morbid-OSA. However, the real issue is to recognize the problems much earlier, and to understand what can be done to prevent its development. The notions of OSA, UARS, apnea hypopnea index are only historical. There is enough knowledge to date to go beyond these definitions, to recognize problems differently and to lead to the prevention of the factors leading to SDB. The recognition of non-hypoxic sleep-disordered breathing is a step in this direction.

Long-Term Oral Appliance Therapy Improves Daytime Function and Mood in Upper Airway Resistance Syndrome Patients

Objectives

To evaluate the long-term effects of an oral appliance on clinical symptoms, respiratory sleep parameters, sleep quality, and sustained attention in patients with upper airway resistance syndrome (UARS) were compared with placebo.

Methods

This study was a randomized placebo-controlled clinical trial. Thirty UARS patients were randomized in two groups: placebo and mandibular advancement device (MAD) groups. UARS criteria were presence of sleepiness (Epworth Sleepiness Scale ≥ 10) and/or fatigue (Modified Fatigue Impact Scale ≥ 38) associated with an apnea/hypopnea index ≤ 5 and a respiratory disturbance index (RDI) > 5 events/hour of sleep, and/or flow limitation in more than 30% of total sleep time. All patients completed the Pittsburgh Sleep Quality Index (PSQI), the Functional Outcomes of Sleep Questionnaire, the Beck Anxiety and Depression Inventories, underwent full-night polysomnography, multiple sleep latency test, and Psychomotor Vigilance Test (PVT). Evaluations were performed before and after 1.5 years of treatment.

Results

RDI, number of respiratory effort-related arousal, percentage of total sleep time with flow limitation, and arousal index significantly decreased after 1.5 years of MAD treatment. PSQI total score improved, severity of depression symptoms decreased, and mean reaction time in the PVT, based on the first measurement taken at 8:00 am, significantly decreased (p = .03) at the end of the protocol.

Conclusions

The MAD was effective in decreasing respiratory events in UARS patients. For UARS, 1.5 years of oral appliance therapy also improved sleep quality and sustained attention, and decreased the severity of depression symptoms.

Clinical Trial

Efficacy of Oral Appliance for Upper Airway Resistance Syndrome: Randomized, Parallel, Placebo-Controlled Study, NCT02636621.

Idiopathic intracranial hypertension eliminated by counterclockwise maxillomandibular advancement: a case report

INTRODUCTION

Obstructive sleep apnea (OSA) is a secondary cause of intracranial hypertension (IH). Decreased jugular venous drainage has been seen in patients with idiopathic IH.

CLINICAL PRESENTATION

A complex case of a 48-year-old female whose idiopathic IH was put into remission after counterclockwise maxillomandibular advancement (CC-MMA), despite persistence of her OSA.

CONCLUSION

This case highlights the relationship between OSA and IH and points to the significant morbidity that can result from mild OSA and from what are considered borderline intracranial pressures. This indicates the need for a high index of suspicion for actual underlying pathology that can be surgically corrected when patients manifest symptoms of a somatic syndrome. This is the first report in the medical literature of clinical elimination of IH by CC-MMA. The authors propose that this positive outcome was effected via mandibular advancement producing a decrease in jugular venous resistance, allowing improved absorption of cerebrospinal fluid.

Somatic syndromes, insomnia, anxiety, and stress among sleep disordered breathing patients

OBJECTIVES

We tested the hypothesis that the prevalence of somatic syndromes, anxiety, and insomnia among sleep disordered breathing (SDB) patients is correlated with their levels of somatic arousal, the symptoms of increased sympathetic nervous system tone under conditions of stress.

METHODS

We administered the Body Sensation Questionnaire (BSQ; a 17-item questionnaire with increasing levels of somatic arousal scored 17-85) to 152 consecutive upper airway resistance syndrome (UARS) patients and 150 consecutive obstructive sleep apnea/hypopnea (OSA/H) patients. From medical records, we characterized each patient in terms of the presence of syndromes and symptoms into three categories: somatic syndromes (six syndromes), anxiety (anxiety disorders, nightmares, use of benzodiazepines), and insomnia (sleep onset, sleep maintenance, and use of hypnotics). For the pooled sample of SDB patients, we modeled the correlation of the BSQ score with the presence of each syndrome/symptom parameter within each of the three categories, with adjustment for male vs. female.

RESULTS

Mean BSQ scores in females were significantly higher than those in males (32.5 ± 11.1 vs. 26.9 ± 8.2; mean ± SD). Increasing BSQ scores significantly correlated with increasing prevalence rates of somatic syndromes (p < 0.0001), of anxiety (p < 0.0001), and of insomnia (p ≤ 0.0001). In general, females had higher prevalence rates of somatic syndromes and symptoms of anxiety than males at any BSQ score while rates of insomnia were similar.

CONCLUSIONS

In patients with SDB, there is a strong association between the level of somatic arousal and the presence of stress-related disorders like somatic syndromes, anxiety, and insomnia.

Somatic arousal and sleepiness/fatigue among patients with sleep-disordered breathing

OBJECTIVES

In a large clinical sample, we tested the hypothesis that levels of sleepiness and fatigue among upper airway resistance syndrome (UARS) patients are correlated with levels of somatic arousal (SA; reflecting the sympathetic nervous system component of the stress response). We also tested the correlations of post-treatment change in these three parameters, and we extended the investigation to obstructive sleep apnea/hypopnea (OSA/H) patients.

METHODS

From 5 years of patient data, we obtained scores on the body sensation questionnaire (BSQ), measuring the level of SA, the fatigue severity scale (FSS), and Epworth sleepiness scale (ESS) for 152 consecutive UARS patients and 150 consecutive OSA/H patients. For each group, we correlated the FSS and ESS scores with the BSQ scores. Among the 45 UARS patients and 49 OSA/H patients treated with nasal CPAP who provided post-treatment data, we correlated change in FSS and ESS scores with change in BSQ scores.

RESULTS

Scores on the BSQ, FSS, and ESS for UARS patients and OSA/H patients were comparable. In both UARS and OSA/H patients, both the FSS and ESS scores were positively correlated with the BSQ score. Nasal CPAP use decreased all three questionnaire scores in both patient groups. In the pooled data, changes in FSS were significantly correlated with changes in BSQ.

CONCLUSIONS

Our findings confirm our preliminary observations that sleepiness and fatigue among UARS patients are correlated with their level of SA and suggest that the same is true for OSA/H patients. The decrease of SA following treatment suggests that SDB is a cause of SA among patients with UARS and OSA/H.

[The syndrome of increased upper airways resistance: What are the clinical features and diagnostic procedures?]

The upper airway resistance syndrome "UARS" is a poorly defined entity, often described as a moderate variant of the obstructive sleep apnea syndrome. It is associated with respiratory effort-related arousal, absence of obstructive sleep apnea, and absence of significant desaturation. It is a relatively common condition that predominantly affects non-obese young adults, with no predominance in either sex. The degree of upper airway collapsibility during sleep of patients with UARS is intermediate between that of normal subjects and that of patients with mild-to-moderate sleep apnea syndrome. Craniofacial and palatal abnormalities are often noted. Patients frequently complain of a functional somatic syndrome, especially daytime sleepiness and chronic fatigue. Polysomnography with esophageal pressure measurements remains the gold standard diagnostic test. The absence of any neurological abnormality gives UARS a good prognosis and it is potentially reversible if treated early. However, some studies suggest that untreated UARS has an increased risk of arterial hypertension. It can also evolve into obstructive sleep apnea.

The role of flow limitation as an important diagnostic tool and clinical finding in mild sleep-disordered breathing

Obstructive sleep apnea (OSA) is defined by quantifying apneas and hypopneas along with symptoms suggesting sleep disruption. Subtler forms of sleep-disordered breathing can be missed when this criteria is used. Newer technologies allow for non-invasive detection of flow limitation, however consensus classification is needed. Subjects with flow limitation demonstrate electroencephalogram changes and clinical symptoms indicating sleep fragmentation. Flow limitation may be increased in special populations and treatment with nasal continuous positive airway pressure (CPAP) has been shown to improve outcomes. Titrating CPAP to eliminate flow limitation may be associated with improved clinical outcomes compared to treating apneas and hypopneas.

A Comparison of Personality Characteristics and Psychiatric Symptomatology between Upper Airway Resistance Syndrome and Obstructive Sleep Apnea Syndrome

OBJECTIVE

To investigate the personality characteristics of patients with upper airway resistance syndrome (UARS) and those of patients with obstructive sleep apnea syndrome (OSAS).

METHODS

Eighty-eight patients with UARS and 365 patients with OSAS participated. All patients had a diagnostic full-night attended polysomnography (PSG) and completed the Athens Insomnia Scale (AIS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Symptom Checklist-90-Revision (SCL-90-R) and Eysenck Personality Questionnaire (EPQ).

RESULTS

The UARS group scored significantly higher than the OSAS group on the ESS, AIS, and PSQI (p<0.001). The scores of all SCL-90-R subscales in the UARS group were significantly higher than those in the OSA group (all p<0.001, except for somatization, p=0.016). Patients with UARS scored lower on EPQ-E (extroversion/introversion) (p=0.006) and EPQ-L (lie) (p<0.001) than those with OSA. UARS patients also showed higher scores on EPQ-P (psychoticism) (p=0.002) and EPQ-N (neuroticism) (p<0.001) than OSAS patients.

CONCLUSION

Our results suggest that patients with UARS have worse subjective sleep quality than OSAS patients in spite of their better PSG findings. UARS patients tend to have more neurotic and sensitive personalities than patients with OSAS, which may be a cause of the clinical features of UARS.

Treatment of upper airway resistance syndrome in adults: Where do we stand?

OBJECTIVE

To evaluate the available literature regarding Upper Airway Resistance Syndrome (UARS) treatment.

METHODS

Keywords "Upper Airway Resistance Syndrome," "Sleep-related Breathing Disorder treatment," "Obstructive Sleep Apnea treatment" and "flow limitation and sleep" were used in main databases.

RESULTS

We found 27 articles describing UARS treatment. Nasal continuous positive airway pressure (CPAP) has been the mainstay therapy prescribed but with limited effectiveness. Studies about surgical treatments had methodological limitations. Oral appliances seem to be effective but their efficacy is not yet established.

CONCLUSION

Randomized controlled trials with larger numbers of patients and long-term follow-up are important to establish UARS treatment options.

Simple snoring: not quite so simple after all?

Simple snoring (SS), in the absence of obstructive sleep apnoea (OSA), is a common problem, yet our understanding of its causes and consequences is incomplete. Our understanding is blurred by the lack of consistency in the definition of snoring, methods of assessment, and degree of concomitant complaints. Further, it remains contentious whether SS is independently associated with daytime sleepiness, or adverse health outcomes including cardiovascular disease and metabolic syndrome. Regardless of this lack of clarity, it is likely that SS exists on one end of a continuum, with OSA at its polar end. This possibility highlights the necessity of considering an otherwise 'annoying' complaint, as a serious risk factor for the development and progression of sleep apnoea, and consequent poor health outcomes. In this review, we: 1) highlight variation in prevalence estimates of snoring; 2) review the literature surrounding the distinctions between SS, upper airway resistance syndrome (UARS) and OSA; 3) present the risk factors for SS, in as far as it is distinguishable from UARS and OSA; and 4) describe common correlates of snoring, including cardiovascular disease, metabolic syndrome, and daytime sleepiness.

The association of somatic arousal with the symptoms of upper airway resistance syndrome

OBJECTIVES

We tested the hypothesis that the symptoms of upper airway resistance syndrome (UARS) are manifestations of chronic stress. To accomplish this, we utilized the score on a self-report questionnaire for somatic arousal (a component of stress) to compare somatic arousal between UARS patients and healthy controls and, among all participants, to correlate the level of somatic arousal with the severity of UARS symptoms.

METHODS

We administered the Mood and Anxiety Symptom Questionnaire anxious arousal subscale (MASQaas; a 17-item questionnaire with increasing levels of arousal scored 17-85) to 12 UARS patients and 12 healthy controls and compared scores between groups. For all participants, we correlated the MASQaas scores with scores for the Epworth Sleepiness Scale (ESS), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) scale, Pittsburgh Sleep Quality Index (PSQI), SF-36 Health Survey, and Perceived Deficits Questionnaire (PDQ; assessing cognitive function).

RESULTS

Compared to healthy controls, UARS patients demonstrated increased somatic arousal (MASQaas scores of 18±2 and 28±7, respectively; p<0.0001). For all participants, the MASQaas scores correlated significantly with scores of the ESS (r=0.64; p=0.0008), the FACIT-Fatigue scale (r=-0.89; p<0.0001), the PSQI (r=0.70; p=0.0002), SF-36 Physical component (r=-0.78; p<0.0001), SF-36 Mental component (r=-0.74; p<0.0001), and the PDQ (r=0.89; p<0.0001).

CONCLUSIONS

Our findings suggest that UARS patients have increased levels of the stress component, somatic arousal, proportionate to the severity of their symptoms.