Epidemiology of Obstructive Sleep Apnea: a Population-based Perspective

State of the art transoral robotic surgery for obstructive sleep apnea-hypopnea syndrome

Objective

To review the existing literature on the role of transoral robotic surgery (TORS) for tongue base reduction in the management of adult obstructive sleep apnea-hypopnea syndrome (OSAHS).

Methods

We searched PubMed, MEDLINE, and Scopus databases from the first literature report of this surgical technique to July 30, 2015 for studies investigating the use of TORS for tongue base reduction in treating adult OSAHS. Our primary outcome measures were Apnea– Hypopnea Index (AHI), lowest oxygen saturation (LSAT), Epworth Sleepiness Score (ESS), and the rates of surgical cure (AHI<5) and success (50% reduction in AHI accompanied by a postoperative AHI<20). Our secondary outcome measures were the volume of tissue resected and correlation to AHI, polysomnographic parameters, subjective outcomes, and body mass index. Complications of surgery were also analyzed.

Results

Thirteen articles were critically evaluated for this research. However, only four case series qualified for statistical analysis of postoperative polysomnographic outcomes and six case series for analysis of postoperative complications. They were case series with a total of 451 adult patients. Pooled analysis revealed statistically significant improvements in AHI, LSAT, and ESS after surgery by 26.83/hour, 5.28% and −8.03, respectively. The average rates of surgical cure and success were 23.8% and 66.7%, respectively. No study reported any deaths or complications related to the use of robotic equipment. The major complication rate was 6.9%, and the minor complication rate was 30.0%. Major complications included major bleeding (2.9%), severe odynophagia with dehydration (3.3%), and oropharyngeal stenosis (0.7%). Minor complications included transient bleeding (0.5%), transient dysphagia (3.8%), and dysgeusia (6.6%).

Conclusion

TORS for tongue base reduction, as a component of multilevel surgery, is an effective treatment option for OSAHS with an acceptable morbidity. This conclusion is based on the analysis of the results of multiple case series. Future studies should entail prospective randomized controlled trials with larger sample size for longer follow-up period.

Sleep Disordered Breathing and White Matter Hyperintensities in Community-Dwelling Elders

STUDY OBJECTIVES

To examine the association between markers of sleep-disordered breathing (SDB) and white matter hyperintensity (WMH) volume in an elderly, multiethnic, community-dwelling cohort.

METHODS

This is a cross-sectional analysis from the Washington Heights-Inwood Columbia Aging Project (WHICAP), a community-based epidemiological study of older adults. Structural magnetic resonance imaging was obtained starting in 2004; the Medical Outcomes Study-Sleep Scale (MOS-SS) was administered to participants starting in 2007. Linear regression models were used to assess the relationship between the two MOS-SS questions that measure respiratory dysfunction during sleep and quantified WMH volume among WHICAP participants with brain imaging.

RESULTS

A total of 483 older adults had both structural magnetic resonance imaging and sleep assessment. Self-reported SDB was associated with WMH. After adjusting for demographic and vascular risk factors, WMH volumes were larger in individuals with frequent snoring (β = 2.113, P = 0.004) and among those who reported waking short of breath or with headache (β = 1.862, P = 0.048).

CONCLUSIONS

In community-dwelling older adults, self-reported measures of SDB are associated with larger WMH volumes. The cognitive effects of SDB that are increasingly being recognized may be mediated at the small vessel level.

Obesity and Hypogonadism

The relationship between obesity and hypogonadism is complicated. The relationship is bidirectional and there are numerous causative and correlative factors on both sides of the equation. Obesity is increasing in prevalence in epidemic proportions. Likewise, we are beginning to see the rapid increase in the incidence of male hypogonadism. It is only recently that we are learning the ways in which these 2 conditions exacerbate each other, and we are only beginning to understand how by treating one of these conditions, we can help to treat the other as well.

Periodontal Status in Morbidly Obese Patients With and Without Obstructive Sleep Apnea Syndrome Risk: A Cross-Sectional Study

BACKGROUND

This cross-sectional study aims to investigate the correlation between obstructive sleep apnea syndrome (OSAS) risk with periodontal disease and anthropometric measures in Class III obese patients.

METHODS

Anthropometric measurements were taken from 108 patients of both sexes, aged 30 to 60 years. The Berlin questionnaire (Bq) and the Epworth sleepiness scale (ESS) were applied to determine the risk for OSAS. Full-mouth periodontal status was determined by probing depth, clinical attachment level, gingival bleeding index, and the presence of calculus. Unpaired Student t, χ(2), Fisher exact, and Mann-Whitney U tests were applied to analyze the differences between high and low risk for OSAS groups.

RESULTS

Overall, 81.5% of the patients showed high risk for OSAS, 46.3% had excessive daytime sleepiness, 41.5% were positive for both the Bq and ESS, and 97.2% had periodontal disease (periodontitis = 85.2% and gingivitis = 60.2%). Patients with periodontal disease showed high risk for OSAS (82.9%) and ESS (45.7%). However, there was no influence of periodontal disease on OSAS risk. Periodontitis was not associated with the ESS (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 0.54 to 6.26) or Bq (OR = 0.87, 95% CI = 0.10 to 7.84), nor was gingivitis associated with the ESS (OR = 1.25, 95% CI = 0.48 to 3.25) or Bq (OR = 0.23, 95% CI = 0.03 to 1.84). Waist circumference (P = 0.03), neck circumference (NC, P <0.001), and the percentage of predicted NC (PPNC, P <0.001) were significantly larger in the patients at high risk for OSAS than in those at low risk for OSAS. Daytime sleepiness was also associated with NC (P = 0.02) and PPNC (P = 0.02).

CONCLUSION

There was no association between periodontal disease and OSAS risk in Class III obese patients, but OSAS risk was associated with both NC and PPNC.

Retina nerve fiber layer and choroidal thickness changes in obstructive sleep apnea syndrome

OBJECTIVES

The purpose of this study was to determine the effects of obstructive sleep apnea syndrome (OSAS) on the submacular and peripapillary retinal nerve fiber layer (RNFL) and choroidal thickness (ChT).

METHODS

Eighty-four eyes of 42 male patients with OSAS and 112 eyes of 56 aged-matched and body mass index-matched healthy male subjects were enrolled in this case-control study. The ChT and peripapillary RNFL thickness was measured using enhanced depth imaging optical coherence tomography. The ChT and RNFL thickness measurements of the groups were compared, and correlations among the Apnea Hypopnea Index (AHI) values and these measurements were calculated. Right and left eyes were separately evaluated.

RESULTS

There were no significant differences in the subfoveal and temporal ChT between the groups (p > 0.05). The OSAS group had significantly thicker ChT at 0.5 and 1.5 mm nasal to the fovea in both eyes than the control group (p < 0.05). The peripapillary ChT were significantly thicker in the OSAS group at all segments except for the temporal and superotemporal segments when compared with the control group (p < 0.05 for all quadrants except temporal and superotemporal). When compared with controls, the OSAS group had significantly thinner nasal RNFL thickness in the right eye (p = 0.01) and thinner mean RNFL thickness in both eyes (p < 0.001). Other RNFL thickness measurements were similar between groups (p > 0.05). Between AHI and mean RNFL thickness showed a median negative correlation (r = - 0.411, p = 0.001).

CONCLUSION

The choroidal thickening in patients with OSAS may be associated with the pathophysiology of the neurodegeneration process of the disease.

Use of CPAP in patients with obstructive sleep apnea admitted to the general ward: effect on length of stay and readmission rate

BACKGROUND

Obstructive sleep apnea (OSA) has been associated with multiple cardiovascular comorbidities. Despite increased awareness of OSA and its treatments, the management of OSA in the hospital setting remains below expectations.

METHODS

We retrospectively reviewed the demographics, clinical characteristics, and hospital course on 413 consecutive patients with a history of OSA on domiciliary CPAP therapy admitted to the general medical ward and analyzed the prevalence of CPAP use and its effect on length of stay (LOS), 30-day readmission rate, and time-to-readmission in our tertiary care teaching hospital.

RESULTS

Of the 413 study participants, 264 (64.0 %) patients were receiving CPAP during their hospital admission. Patients who were receiving CPAP therapy during their hospitalization had a significantly higher body mass index (BMI) (41.4 vs. 36.8 kg/m(2), p < 0.001) and were more likely to be African-American (p = 0.01) and have congestive heart failure (CHF) (42.0 vs. 31.0 %, p = 0.038) peripheral vascular disease (PVD) (26.0 vs. 15.0 %, p = 0.013), and uncomplicated diabetes mellitus (p = 0.001) than those who were not. CPAP therapy in the hospital setting did not affect LOS (4.7 vs. 4.0 days, p = 0.291), readmission rate (11.0 % for both groups), or time-to-readmission (20.8 vs. 22.3 days, p = 0.762).

CONCLUSION

The majority of patients who are on domiciliary CPAP therapy were receiving CPAP therapy while admitted to the general medical ward of a tertiary care academic hospital. Presence of comorbid conditions such as obesity and certain cardiovascular diseases may have increased the likelihood of prescribing CPAP therapy while in the hospital. In-hospital CPAP therapy did not appear to significantly influence short-term outcomes such as hospital LOS, readmission rate, or time-to-readmission.

Bariatric Surgery or Non-Surgical Weight Loss for Obstructive Sleep Apnoea? A Systematic Review and Comparison of Meta-analyses

BACKGROUND

Obstructive sleep apnoea (OSA) is a well-recognised complication of obesity. Non-surgical weight loss (medical, behavioural and lifestyle interventions) may improve OSA outcomes, although long-term weight control remains challenging. Bariatric surgery offers a successful strategy for long-term weight loss and symptom resolution.

OBJECTIVES

To comparatively appraise bariatric surgery vs. non-surgical weight loss interventions in OSA treatment utilising body mass index (BMI) and apnoea-hypopnoea index (AHI) as objective measures of weight loss and apnoea severity.

METHODS

A systematic literature review revealed 19 surgical (n = 525) and 20 non-surgical (n = 825) studies reporting the primary endpoints of BMI and AHI before and after intervention. Data were meta-analysed using random effects modelling. Subgroup analysis, quality scoring and risk of bias were assessed.

RESULTS

Surgical patients had a mean pre-intervention BMI of 51.3 and achieved a significant 14 kg/m(2) weighted decrease in BMI (95%CI [11.91, 16.44]), with a 29/h weighted decrease in AHI (95%CI [22.41, 36.74]). Non-surgical patients had a mean pre-intervention BMI of 38.3 and achieved a significant weighted decrease in BMI of 3.1 kg/m(2) (95%CI [2.42, 3.79]), with a weighted decrease in AHI of 11/h (95%CI [7.81, 14.98]). Heterogeneity was high across all outcomes.

CONCLUSIONS

Both bariatric surgery and non-surgical weight loss may have significant beneficial effects on OSA through BMI and AHI reduction. However, bariatric surgery may offer markedly greater improvement in BMI and AHI than non-surgical alternatives. Future studies must address the lack of randomised controlled and comparative trials in order to confirm the exact relationship between metabolic surgery and non-surgical weight loss interventions in OSA resolution.

Prevalence and risks of habitual snoring and obstructive sleep apnea symptoms in adult dental patients

OBJECTIVES

To determine the prevalence of habitual snoring and risk of obstructive sleep apnea (OSA) among dental patients and investigate factors associated with high-risk OSA.

METHODS

This cross-sectional study was performed at the Department of Preventive Dental Sciences, College of Dentistry, University of Dammam, Kingdom of Saudi Arabia, between October and December 2014. A total of 200 consecutive female and male dental patients were included in this study. Subjective and objective assessments were carried out. Habitual snoring and risk of OSA were assessed using the Arabic version of the Berlin questionnaire. Two trained investigators carried out the objective measurements of anthropometric data, blood pressure, oxygen saturation, pulse rate, and clinical examination of upper-airway, and dental occlusion. 

RESULTS

Habitual snoring was present in 18.2% of the females and 81.8% of the males (p less than 0.05). Breathing pauses during sleep of more than once a week occurred in 9% (n=17) of the sample. Of the males, 78.3% were at high risk of OSA compared with 21.7% of the females. Multivariate analysis for risk of OSA revealed that obese patients were almost 10 times more likely to report OSA symptoms than their non-obese counterparts (odds ratio: 9.9, 95% confidence intervals: 4.4-22.1). Tongue indentations, tonsil size, and a high Epworth Sleepiness Scale score were also independent risks of OSA.

CONCLUSION

Tongue indentations and tonsil grades III and IV were significantly associated with risk of OSA. This validates the important role of dentists in the recognition of the signs and symptoms of OSA.

The Impact of Obstructive Sleep Apnea and Tobacco Smoking on Endothelial Function

BACKGROUND

Endothelial dysfunction has been recognized to occur in the context of obstructive sleep apnea (OSA) or tobacco smoking. However, the deleterious effect on vascular function with concurrence of both conditions is largely unknown.

OBJECTIVE

To investigate whether the concurrence of OSA and smoking poses an additive detriment to endothelial dysfunction.

METHODS

Chinese men without a history of chronic medical illness were invited to complete a questionnaire including smoking pack-year exposure, polysomnography and peripheral arterial tonometry (PAT) for endothelial function. Serum 8-isoprostane, advanced oxidation protein products (AOPP) and monocyte chemo-attractant protein-1 (MCP-1) were measured.

RESULTS

114 men were successfully enrolled. PAT ratio, adjusted for age and body mass index, correlated inversely with overall severity of OSA: apnea-hypopnea index (AHI), r = -0.160 (p = 0.092); oxygen desaturation index, r = -0.214 (p = 0.024); duration of oxygen saturation <90%, r = -0.219 (p = 0.020); and minimum oxygen saturation, r = 0.250 (p = 0.008). The PAT ratio decreased with increasing pack-year group (p = 0.018). It was lower with concurrent smoking history and moderate-severe OSA (AHI ≥15/h) compared to having one or neither factor (p = 0.011). Serum levels of 8-isoprostane and AOPP were positively related to severity of OSA, while MCP-1 correlated with smoking quantity. Multiple linear regression analyses showed that severity of intermittent hypoxia, MCP-1 and pack-year exposure were independent predictors of PAT ratio.

CONCLUSION

While OSA, in particular intermittent hypoxemia, and tobacco smoking were independent risk factors, the concurrence of moderate-severe OSA and smoking was associated with the most severe impairment in endothelial function.

Obstructive sleep apnoea and risks of all-cause mortality: preliminary evidence from prospective cohort studies

PURPOSE

A meta-analysis of prospective cohort studies was conducted to clarify the association between obstructive sleep apnoea (OSA) and future risk of all-cause mortality.

METHODS

Eligible studies were identified by searching the PubMed and EMBASE databases up to July 2015. Pooled hazard ratios (HRs) and their corresponding 95 % confidence intervals (CIs) were calculated to estimate the association between OSA and risk of all-cause mortality. Sources of heterogeneity were identified by subgroup and meta-regression analyses.

RESULTS

Twelve prospective cohort studies involving 34,382 participants were included in this meta-analysis. The pooled HR of all-cause mortality was 1.262 (95 % CI 1.093-1.431) with significant heterogeneity. Subgroup analyses indicated that the pooled HRs of all-cause mortality in patients with mild, moderate and severe OSA were 0.945 (95 % CI 0.810-1.081), 1.178 (95 % CI 0.978-1.378) and 1.601 (95 % CI 1.298-1.902), respectively. OSA severity could be a possible sources of heterogeneity. Existing publication bias produced a minor contribution to effect size.

CONCLUSION

Severe, but not mild to moderate, OSA is significantly associated with increased risk of all-cause mortality.

Determinants of sexual dysfunction and interventions for patients with obstructive sleep apnoea: a systematic review

AIMS

Obstructive sleep apnoea (OSA) may negatively affect a couple's sexual relationship. This systematic review evaluated what characteristics are determinants of sexual function and dysfunction in women and men with OSA, and what interventions are shown to be effective.

METHODS

A systematic literature review was conducted using PubMed, CINAHL, Cochrane and TRIP, and articles published between January 2004 and December 2014 in English; original research; adults ≥ 18 years; and both experimental and non-experimental designs. The Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies was used to assess study quality. Of 21 studies, six studies (no randomised control trials, RCTs) included women and 15 (with six RCTs) studies included men. Extracted data were scrutinised and adjusted until consensus was reached; suitable quantitative data were pooled in statistical meta-analysis.

RESULTS

Sexual function was affected similarly in both genders, but effective interventions were reported only for men. In some studies, OSA severity and medications contributed to greater sexual dysfunction. In women, menopausal status, hormone levels and SaO2 < 90% were determinants of sexual dysfunction, while for men factors included BMI, hormonal status and inflammatory markers. Continuous positive airway pressure (CPAP) not only improved clinical measures such as excessive daytime sleepiness but also the erectile and orgasmic function. Nevertheless, sildenafil was superior CPAP with regard to erectile dysfunction.

CONCLUSIONS

The findings illustrate important contributors to sexual dysfunction; however, firm generalisations cannot be made. There were limited RCTs and none for women, indicating further RCTs are needed to determine how OSA affects sexual function.

Outcome of TORS to tongue base and epiglottis in patients with OSA intolerant of conventional treatment

PURPOSE

Transoral robotic surgery (TORS) of the tongue base with or without epiglottoplasty represents a novel treatment for obstructive sleep apnea (OSA). The objective was to evaluate the clinical efficacy of TORS of the tongue base with or without epiglottoplasty in patients who had not tolerated or complied with conventional treatment (continuous positive airway pressure or oral appliance).

METHODS

Four-year prospective case series. The primary outcome measure was the apnea-hypopnea index (AHI) in combination with the Epworth Sleepiness Score (ESS). Mean oxygen saturation levels (SaO2) before and after TORS on respective sleep studies were also recorded. Secondary outcome measures included operative time and complications. Patient reported outcome measures (PROMs) assessed included voice, swallow and quality of life.

RESULTS

Fourteen patients underwent TORS for tongue base reduction with ten having additional wedge epiglottoplasty. A 64 % success rate was achieved with a normal post-operative sleep study in 36 % of cases at 6 months. There was a 51 % reduction in the mean AHI (36.3 ± 21.4 to 21.2 ± 24.6, p = 0.02) and a sustained reduction in the mean Epworth Sleepiness Score (p = 0.002). Mean SaO2 significantly increased after surgery compared to pre-operative values (92.9 ± 1.8 to 94.3 ± 2.5, p = 0.005). Quality of life showed a sustained improvement 3 months following surgery (p = 0.01). No major complications occurred.

CONCLUSIONS

TORS of the tongue base with or without epiglottoplasty represents a promising treatment option with minimal morbidity for selected patients with OSA. Long-term prospective comparative evaluation is necessary to validate the findings of this study.

Controversies in perioperative anesthetic management of the morbidly obese: I am a surgeon, why should I care?

Over the last four decades, as the rates of obesity have increased, so have the challenges associated with its anesthetic management. In the present review, we discuss perioperative anesthesia management issues that are modifiable by the early involvement of the surgical team. We sum up available evidence or expert opinion on issues like patient positioning, postoperative analgesia, and the effect of continuous positive airway pressure (CPAP) ventilation on surgical anastomosis. We also address established predictors of higher perioperative risk and suggest possible management strategies and concerns of obese patients undergoing same day procedures. Finally, a generalized pharmacological model relevant to altered pharmacokinetics in these patients is presented.

Relationship between Clinical and Polysomnography Measures Corrected for CPAP Use

OBJECTIVES

The changes in patient-reported measures of obstructive sleep apnea (OSA) burden are largely discordant with the change in apnea-hypopnea index (AHI) and other polysomnography measures before and after treatment. For patients treated with continuous positive airway pressure (CPAP), some investigators have theorized that this discordance is due in part to the variability in CPAP use. We aim to test the hypothesis that patient-reported outcomes of CPAP treatment have stronger correlations with AHI when it is corrected for mean nightly CPAP use.

METHODS

This was a cross-sectional study of 459 adults treated with CPAP for OSA. Five patient-reported measures of OSA burden were collected at baseline and after 6 months of CPAP therapy. The correlations between the change in each patient-reported measure and the change in AHI as well as mean nightly AHI (corrected for CPAP use with a weighted average formula) were measured after 6 months of treatment. The same analysis was repeated for 4 additional polysomnography measures, including apnea index, arousal index, lowest oxyhemoglobin saturation, and desaturation index.

RESULTS

The change in AHI was weakly but significantly correlated with change in 2 of the 5 clinical measures. The change in mean nightly AHI demonstrated statistically significant correlations with 4 out of 5 clinical measures, though each with coefficients less than 0.3. Similar results were seen for apnea index, arousal index, lowest oxyhemoglobin saturation, and desaturation index.

CONCLUSIONS

Correction for CPAP use yielded overall small but significant improvements in the correlations between patient-reported measures of sleep apnea burden and polysomnography measures after 6 months of treatment.

Evaluation of water content around airway in obstructive sleep apnea patients using peripharyngeal mucosal T2 magnetic resonance imaging

INTRODUCTION

Obstructive sleep apnea (OSA) is common sleep disorder characterized by repetitive episodes of airway closure which usually occurs in the retropalatal region of the oropharynx. It has been known that upper airway mucosa in OSA patients is described as edematous, but not fully clarified.

OBJECTIVES

This study aimed to investigate and establish magnetic resonance imaging (MRI) parameter to estimate tissue water content at retropalatal level and its relationship with sleep parameters in OSA patients.

METHODS

Forty-eight subjects with OSA underwent overnight polysomnography and cervical MRI with 1.5-tesla [mean (SD) age 55 (14) years and apnea-hypopnea index (AHI) 45.2 (26.1) events/hour, 79.2% male]. On the axial T2-weighted images from epipharynx to oropharynx, the signal intensities of masseter muscle and peripharyngeal mucosa [T2 mucous-to-masseter intensity ratio (T2MMIR)], was used as water content estimation in the retropalatal region. Partial correlation analysis was performed to examine the correlation between T2MMIR and polysomnography parameters.

RESULTS

We found that there were strong and positive correlations between the T2MMIR and AHI (r = 0.545, P < 0.05), supine AHI (r = 0.553, P < 0.05) and REM AHI (r = 0.640, P < 0.01) by partial correlation analysis. Besides, in patients with less efficient sleep who had more stage 1 sleep, significantly higher T2MMIR was noted (r = 0.357, P < 0.05).

CONCLUSIONS

This study confirmed that peripharyngeal T2MMIR can be a simple parameter representing peripharyngeal tissue water contents related to severe OSA.

The effects of moderate energy restriction on apnoea severity and CVD risk factors in obese patients with obstructive sleep apnoea

Nutritional intervention for weight loss is one of the treatment options for obstructive sleep apnoea (OSA) in patients with overweight or obesity. However, the effects of moderate energy restriction on OSA severity are not yet known. The present study aimed to evaluate the effects of moderate energy restriction on OSA severity and CVD risk factors in obese patients with OSA. In this 16-week randomised clinical trial, twenty-one obese subjects aged 20-55 years and presenting an apnoea/hypopnoea index (AHI)≥5 events/h were randomised into two groups: the energy restriction group (ERG) and the control group (CG). The ERG was instructed to follow an energy-restricted diet -3347·2 kJ/d (-800 kcal/d) and the CG was advised not to change their food intake. At the beginning and at the end of the study, participants underwent evaluation of the following: OSA (Watch-PAT200®), nutritional parameters, blood pressure, sympathetic activity, inflammatory biomarkers, metabolic profile and endothelial function. The ERG (n 11), compared with the CG (n 10), had a significantly greater reduction in body weight (Cohen's d=-1·19; P<0·001), in AHI (Cohen's d=-0·95; P=0·04) and in plasma concentrations of adrenaline (Cohen's d=-1·02; P=0·04) as well as a significantly greater increase in minimum O2 saturation (Cohen's d=1·08; P=0·03). Although energy restriction was not associated with significant improvements in CVD risk factors, medium-to-large effect sizes were observed, suggesting that the statistically non-significant difference between groups may be due to the small sample size. This study suggests that in obese patients with OSA, moderate energy restriction is able to reduce the parameters of OSA severity and sympathetic activity.

Weighted STOP-Bang and screening for sleep-disordered breathing

BACKGROUND

STOP-Bang is a tool for predicting the likelihood for sleep-disordered breathing (SDB). In the conventional score, all variables are dichotomous. Our aim was to identify whether modifying the STOP-Bang scoring tool by weighting the variables could improve test characteristics.

METHODS

Subjects who participated in the Sleep Heart Health Study (SHHS) were included in this analysis using a derivation dataset (n = 1667) and a validation dataset (n = 4774). In the derivation dataset, each STOP-Bang variable was evaluated using linear regression against the presence of SDB (AHI > 15/h) in order to determine the coefficients that would allow variable weighting. In other models, BMI, age, and neck circumference were entered as continuous variables. The sum of the weighted dichotomous variables yielded a weighted STOP-Bang (wSTOP-Bang). The sum of the weighted-continuous variables yielded a continuous STOP-Bang (cSTOP-Bang). The wSTOP-Bang, cSTOP-Bang, and the conventional STOP-Bang scores were then applied to the validation dataset, and receiver operating characteristic (ROC) curves were constructed.

RESULTS

The area under the curve (AUC) for cSTOP-Bang (0.738) was greater than the AUC for conventional STOP-Bang (0.706) and wSTOP-Bang (0.69). The sensitivities for cSTOP-Bang, STOP-Bang, and wSTOP-Bang were similar at 93.2, 93.2, and 93.3 %, respectively. The cSTOP-Bang had a higher specificity (31.8 %) than both STOP-Bang (23.2 %) and wSTOP-Bang (23.6 %). The cSTOP-Bang had a higher likelihood ratio of a positive test (1.36) than both STOP-Bang (1.21) and wSTOP-Bang (1.22).

CONCLUSIONS

Modifying the STOP-Bang score by weighting the variables and using continuous variables for BMI, age, and neck circumference can maintain sensitivity while improving specificity, positive likelihood ratio, and area under the receiver operating characteristic curve.

Sleep Disordered Breathing in Four Resource-Limited Settings in Peru: Prevalence, Risk Factors, and Association with Chronic Diseases

STUDY OBJECTIVES

Sleep disordered breathing (SDB) is a highly prevalent condition in high-income countries, with major consequences for cardiopulmonary health, public safety, healthcare utilization, and mortality. However, its prevalence and effect in low- and middle-income countries are less well known. We sought to determine the prevalence, risk factors, and comorbidities of SDB symptoms in four resource-limited settings.

DESIGN

Cross-sectional analysis of the CRONICAS Cohort, a population-based age- and sex-stratified sample.

SETTING

Four resource-limited settings in Peru varying in altitude, urbanization, and air pollution.

PARTICIPANTS

There were 2,682 adults aged 35 to 92 y.

MEASUREMENTS AND RESULTS

Self-reported SDB symptoms (habitual snoring, observed apneas, Epworth Sleepiness Scale), sociodemographics, medical history, anthropometrics, spirometry, blood biomarkers were reported. We found a high prevalence of habitual snoring (30.2%, 95% confidence interval [CI] 28.5-32.0%), observed apneas (20.9%, 95% CI 19.4-22.5%) and excessive daytime sleepiness (18.6%, 95% CI 17.1-20.1%). SDB symptoms varied across sites; prevalence and adjusted odds for habitual snoring were greatest at sea level, whereas those for observed apneas were greatest at high altitude. In multivariable analysis, habitual snoring was associated with older age, male sex, body mass index (BMI), and higher socioeconomic status; observed apneas were associated with BMI; and excessive daytime sleepiness was associated with older age, female sex, and medium socioeconomic status. Adjusted odds of cardiovascular disease, depression, and hypertension and total chronic disease burden increased progressively with the number of SDB symptoms. A threefold increase in the odds of having an additional chronic comorbid disease (adjusted odds ratio 3.57, 95% CI 2.18-5.84) was observed in those with all three versus no SDB symptoms.

CONCLUSIONS

Sleep disordered breathing symptoms were highly prevalent, varied widely across four resource-limited settings in Peru, and exhibited strong independent associations with chronic diseases.

Obstructive Sleep Apnea and Kidney Disease: A Potential Bidirectional Relationship?

Chronic kidney disease (CKD) is associated with high mortality rates and heavy economic and social burdens. Nearly 10% of the United States population suffer from CKD, with fatal outcomes increased by 16-40 times even before reaching end-stage renal disease. The prevalence of obstructive sleep apnea (OSA) is between 3% and 7% in the general population, and has increased dramatically during the last 2 decades along with increased rates of obesity. However, the prevalence of OSA is much greater in patients with CKD. In addition, aggressive dialysis improves OSA. The current literature suggests a bidirectional association between CKD and OSA through a number of potential pathological mechanisms, which increase the possibility of both diseases being possible risk factors for each other. CKD may lead to OSA through a variety of mechanisms, including alterations in chemoreflex responsiveness, pharyngeal narrowing due to fluid overload, and accumulation of uremic toxins. It is also being increasingly recognized that OSA can also accelerate loss of kidney function. Moreover, animals exposed to intermittent hypoxia suffer histopathological renal damage. Potential mechanisms of OSA-associated renal dysfunction include renal hypoxia, hypertension, endothelial dysfunction, activation of the sympathetic nervous system, and increased oxidative stress.

Disparities in sleep characteristics by race/ethnicity in a population-based sample: Chicago Area Sleep Study

BACKGROUND

Prior studies report less favorable sleep characteristics among non-Whites as compared with non-Hispanic Whites. However, few population-based studies have used objective measures of sleep duration, especially in more than two racial/ethnic groups. We tested whether objectively estimated sleep duration and self-reported sleep quality varied by race and whether differences were at least partially explained by the variability in clinical, psychological, and behavioral covariates.

METHODS

Adults aged 35-64 years who self-identified as White, Black, Asian, or Hispanic were randomly sampled from Chicago, IL, and the surrounding suburbs. Our analytic sample included adults who had an apnea-hypopnea index <15 after one night of screening and who completed seven nights of wrist actigraphy for determination of sleep duration, sleep percentage, minutes of wake after sleep onset, and sleep fragmentation (n = 495). Daytime sleepiness was estimated using the Epworth Sleepiness Scale (ESS), and sleep quality was estimated from the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Following statistical adjustment for age, gender, education, work schedule (ie, day vs. night shift), smoking status, depressive symptoms, body mass index (BMI), hypertension, and diabetes, sleep duration (minutes) was significantly (all p < 0.01) shorter in Black (mean = 399.5), Hispanic (mean = 411.7), and Asian (mean = 409.6) participants than in White participants (mean = 447.4). All remaining sleep characteristics were significantly less favorable among Black participants as compared with White participants. Asian participants also reported significantly more daytime sleepiness than did White participants.

CONCLUSIONS

Differences in sleep characteristics by race/ethnicity are apparent in a sample of adults with a low probability of sleep apnea and following adjustment for known confounders.

The rising incidence of spontaneous cerebrospinal fluid leaks in the United States and the association with obesity and obstructive sleep apnea

OBJECTIVE

To determine the national rates of spontaneous CSF leaks and to determine the association with risk factors.

STUDY DESIGN

Retrospective review from 2002 to 2012.

SETTING

University HealthSystem Consortium (UHC) database of 127 of the leading academic medical centers in the United States (81 centers participated all years of the study).

PATIENTS

Those who underwent craniotomy for CSF leak repair in the UHC database and those who have undergone repair of spontaneous CSF leaks at one UHC center.

INTERVENTION

Assessment of procedure code rates and patient demographics from 2002 to 2012.

MAIN OUTCOME MEASURE

National rates of craniotomy for spontaneous CSF leak repair each year, the relation to U.S. regional obesity rates, and the proportion of patients with coincident obstructive sleep apnea. Spontaneous CSF leak patient characteristics (age, sex, BMI, hypertension, and OSA) were calculated.

RESULTS

The rate of craniotomy for spontaneous CSF leak repair has risen 2 fold from 2002 (218 cases per year) to 2012 (488 cases per year). There was no change in the rate of nonspontaneous CSF leaks over the same period. The rate of spontaneous CSF leak repair is twice as high (2.54 versus 1.07 per million people per year) in regions of the United States with the highest obesity rate (Midwest) compared with the lowest obesity rate (West). All patients with spontaneous CSF leaks were overweight (BMI, >25 kg/m2) with an average BMI of 37.8 kg/m2. The average age was 57.03 years, and 72% were female. Patients with spontaneous CSF leaks presented with high rate of OSA (14.8% nationally and 37.1% at the University of Iowa) and hypertension (85.7%).

CONCLUSION

The national rate of craniotomy for spontaneous CSF leak repair is rising. This condition is yet another public health problem related to the rising obesity epidemic. All patients with spontaneous CSF leaks should be evaluated for OSA.

Symptoms of Obstructive Sleep Apnea, Gastroesophageal Reflux and the Risk of Barrett's Esophagus in a Population-Based Case-Control Study

Background

Gastroesophageal reflux is overrepresented in people with obstructive sleep apnea (OSA) and it has been suggested that OSA worsens gastroesophageal reflux symptoms. Aggravated reflux might lead to an increased risk of Barrett’s esophagus.

Aim

To assess the association between sleep apnea symptoms and Barrett’s esophagus.

Methods

Included in a case-control study in Brisbane, Australia were 237 patients with histologically confirmed Barrett’s esophagus and 247 population controls. The controls were randomly selected from the electoral roll and frequency-matched to the cases by age and sex. Information on OSA symptoms (excessive daytime sleepiness and sleep related apnea symptoms), gastroesophageal reflux symptoms and anthropometric measures were collected through interviews and written questionnaires. Multivariable logistic regression provided odds ratios (OR) and 95% confidence intervals (CI), adjusted for potential confounding by BMI and gastroesophageal reflux.

Results

The prevalence of Barrett’s esophagus was higher among people with excessive daytime sleepiness than those without (24% vs. 18%; p-value 0.1142) and in participants with sleep-related apnea symptoms (20% vs. 13%; p-value 0.1730). However, there were non-significantly increased ORs of Barrett’s esophagus among people with excessive daytime sleepiness (OR 1.42, 95% CI 0.90–2.34) and sleep related apnea symptoms (OR 1.32, 95% CI 0.74–2.36) when adjusting for age, sex and BMI. After further adjustment for gastroesophageal reflux symptoms, the point ORs were no longer increased (OR 1.02, 95% CI 0.61–1.70 for daytime sleepiness and OR 0.72, 95% CI 0.38–1.38 for sleep related apnea symptoms).

Conclusions

Symptoms of OSA are possibly associated with an increased risk of Barrett’s esophagus, an association that appears to be mediated entirely by gastroesophageal reflux.

Design and Evaluation of an Intelligent Remote Tidal Volume Variability Monitoring System in E-Health Applications

A reliable long-term monitoring and diagnosis of breath disorders at an early stage provides an improvement of medical act, life expectancy, and quality of life while decreasing the costs of treatment and medical services. Therefore, a real-time unobtrusive monitoring of respiration patterns, as well as breath parameters, is a critical need in medical applications. In this paper, we propose an intelligent system for patient home care, capable of measuring respiration rate and tidal volume variability via a wearable sensing technology. The proposed system is designed particularly for the goal of diagnosis and treatment in patients with pathological breathing, e.g., respiratory complications after surgery or sleep disorders. The complete system was comprised of wearable calibrated accelerometer sensor, Bluetooth low energy, and cloud database. The experiments are conducted with eight subjects and the overall error in respiration rate calculation is obtained 0.29%±0.33% considering SPR-BTA spirometer as the reference. We also introduce a method for tidal volume variability estimation while validated using Pearson correlation. Furthermore, since it is essential to detect the critical events resulted from sudden rise or fall in per breath tidal volume of the patients, we provide a technique to automatically find the accurate threshold values based on each individual breath characteristics. Therefore, the system is able to detect the major changes, precisely by more than 98%, and provide immediate feedback such as sound alarm for round-the-clock respiration monitoring.

OSA and pulmonary hypertension: time for a new look

OSA is a common yet underdiagnosed disorder encountered in everyday practice. The disease is a unique physiologic stressor that contributes to the development or progression of many other disorders, particularly cardiovascular conditions. The pulmonary circulation is specifically affected by the intermittent hypoxic apneas associated with OSA. The general consensus has been that OSA is associated with pulmonary hypertension (PH), but only in a minority of OSA patients and generally of a mild degree. Consequently, there has been no sense of urgency to screen for either condition when evaluating the other. In this review, we explore available evidence describing the interaction between OSA and PH and seek to better understand underlying pathophysiology. We describe certain groups of patients who have a particular preponderance of OSA and PH. Failure to recognize the mutual additive effects of these disorders can lead to suboptimal patient outcomes. Among patients with PH and OSA, CPAP, the mainstay treatment for OSA, may ameliorate pulmonary pressure elevations, but has not been studied adequately. Conversely, among patients with OSA, PH significantly limits functional capacity and potentially shortens survival; yet, there is no routine screening for PH in patients with OSA. We think it is time to study the interaction between OSA and PH more carefully to identify high-risk subgroups. These would be screened for the presence of combined disorders, facilitating earlier institution of therapy and improving outcomes.

Poor responders to bevacizumab pharmacotherapy in age-related macular degeneration and in diabetic macular edema demonstrate increased risk for obstructive sleep apnea

PURPOSE

To investigate the risk for obstructive sleep apnea (OSA) in patients with exudative age-related macular degeneration (AMD) or diabetic macular edema with poor response to anti-vascular endothelial growth factor therapy with bevacizumab (Avastin).

METHODS

Age-related macular degeneration group was categorized into nonexudative, exudative, or poor response exudative. Diabetic macular edema group included patients with nonproliferative diabetic retinopathy and cystoid macular edema. Patients were categorized based on the number of intravitreal injections of bevacizumab received. Both groups were compared with age-matched controls. Patients completed a screening questionnaire to assess the risk for OSA, the main outcome measure.

RESULTS

Of 103 patients with AMD, 56 (54.37%) had nonexudative AMD and 47 (45.63%) had exudative AMD, of which 14 (29.79%) had poor response exudative AMD and were at a significantly higher risk of OSA (P < 0.05). Of 30 diabetic macular edema patients with cystoid macular edema, 4 (19%) received 1 injection, 18 (81.82%) received 2 or more consecutive injections, and 16 (72.73%) received 3 or more consecutive injections. Risk for OSA increased significantly with increasing number of injections (P < 0.05).

CONCLUSION

Patients with exudative AMD and diabetic macular edema with poor response to anti-vascular endothelial growth factor therapy have a significantly higher risk of OSA compared with age-matched controls and should be screened to assess the risk of OSA.

Volumetric MRI analysis pre- and post-Transoral robotic surgery for obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

To quantitatively measure volumetric changes in upper airway soft tissue structures using magnetic resonance imaging (MRI) pre- and post transoral robotic surgery for obstructive sleep apnea (OSA-TORS).

STUDY DESIGN

Prospective, nonrandomized, institutional board-approved study.

METHODS

Apneics undergoing OSA-TORS, which included bilateral posterior hemiglossectomy with limited pharyngectomy and uvulopalatopharyngoplasty, had upper airway MRIs pre- and postoperatively. Changes (percent and absolute values) in upper airway and surrounding soft tissue volumes were calculated. We assessed whether there were significant volumetric changes and if changes correlated with apnea-hypopnea index (AHI) changes.

RESULTS

Nineteen MRIs and 18 polysomnograms were analyzed pre- and postoperation. Total airway volume increased by 19.4% (P = 0.030). Soft palate and tongue volumes decreased by 18.3% (P = 0.002) and 5.8% (P = 0.013), respectively. Retropalatal and total lateral wall volumes decreased by 49.8% (P = 0.0001) and 17.9% (P = 0.008), respectively. Changes in other structures were not significant. Eleven patients had surgical success, with a mean AHI decrease of 52.9; six were nonsuccesses with a mean AHI decrease of 4.5 (P =0.006). Decreased retropalatal lateral wall volume correlated with decreased AHI.

CONCLUSION

Airway, tongue, soft palate, and lateral wall volumes change significantly after OSA-TORS. Changes in the volume of the lateral walls correlated with changes in AHI. Volumetric upper airway MRI may be a helpful tool to better understand reasons for surgical success.

LEVEL OF EVIDENCE

4.

A pilot study: portable out-of-center sleep testing as an early sleep apnea screening tool in acute ischemic stroke

INTRODUCTION

Prompt diagnosis of obstructive sleep apnea (OSA) after acute ischemic stroke (AIS) is critical for optimal clinical outcomes, but in-laboratory conventional polysomnograms (PSG) are not routinely practical. Though portable out-of-center type III cardiopulmonary sleep studies (out-of-center cardiopulmonary sleep testing [OCST]) are widely available, these studies have not been validated in patients who have recently suffered from AIS. We hypothesized that OCST in patients with AIS would yield similar results when compared to conventional PSG.

METHODS

Patients with AIS had simultaneous type III OCST and PSG studies performed within 72 hours from symptom onset. The accuracy of OCST was compared to PSG using: chi-square tests, receiver operatory characteristic curves, Bland-Altman plot, paired Student's t-test/Wilcoxon signed-rank test, and calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Twenty-one out of 23 subjects with AIS (age 61±9.4 years; 52% male; 58% African-American) successfully completed both studies (9% technical failure). Nearly all (95%) had Mallampati IV posterior oropharynx; the mean neck circumference was 16.8±1.6 in. and the mean body mass index (BMI) was 30±7 kg/m(2). The apnea hypopnea index (AHI) provided by OCST was similar to that provided by PSG (19.8±18.0 vs 22.0±22.7, respectively; P=0.49). On identifying subjects by OCST with an AHI ≥5 on PSG, OCST had the following parameters: sensitivity 100%, specificity 85.7%, PPV 93%, and NPV 100%. On identifying subjects with an AHI ≥15 on PSG, OCST parameters were as follows: sensitivity 100%, specificity 83.3%, PPV 81.8%, and NPV 100%. Bland-Altman plotting showed an overall diagnostic agreement between OCST and PSG modalities for an AHI cutoff >5, despite fine-grained differences in estimated AHIs.

CONCLUSION

Compared with PSG, OCST provides similar diagnostic information when run simultaneously in AIS patients. OCST is a reliable screening tool for early diagnosis of OSA in AIS patients.

The CC genotype of the delta-sarcoglycan gene polymorphism rs13170573 is associated with obstructive sleep apnea in the Chinese population

Obstructive sleep apnea (OSA) is a highly heterogeneous sleep disorder, and increasing evidence suggests that genetic factors play a role in the etiology of OSA. Airway muscle dysfunction might promote pharyngeal collapsibility, mutations or single nucleotide polymorphisms (SNPs) in the delta-sarcoglycan (SCGD) gene associated with muscle dysfunction. To evaluate if SCGD gene SNPs are associated with OSA, 101 individuals without OSA and 97 OSA patients were recruited randomly. The genotype distributions of SNPs (rs157350, rs7715464, rs32076, rs13170573 and rs1835919) in case and control populations were evaluated. The GG, GC and CC genotypes of rs13170573 in control and OSA groups were 51.5% and 37.1%, 36.6% and 35.1%, and 11.9% and 27.8%, respectively. Significantly fewer OSA patients possessed the GG genotype and significantly more possessed the CC genotype compared with controls. Further multivariate logistic regression analysis showed that the CC genotype was an independent risk factor for OSA, with an odds ratio (OR) of 2.17 (95% confidence interval [CI]: 1.19-6.01). Other factors, such as age ≥ 50 years, male gender, body mass index (BMI) ≥ 25 kg/m(2), low-density lipoprotein cholesterol (LDL-C) level ≥ 3.33 mg/dL, smoking and hypertension, were also independent risk factors for OSA in our multivariate logistic regression model.

The effect of infrahyoid muscle sectioning on hyoid bone position and oropharyngeal air column volume

OBJECTIVE/HYPOTHESIS

To evaluate the spatial hyoid bone position and the oropharyngeal air column volume after infrahyoid muscle sectioning as a single procedure.

STUDY DESIGN

Animal experiment.

METHODS

Six adult New Zealand rabbits underwent sternohyoid, omohyoid, and thyrohyoid muscle sectioning for infrahyoid release. Preoperative and postoperative computed tomography scans were obtained and transferred to the Mimics software program. By using the program, preoperative and postoperative three-dimensional models of the spatial hyoid bone position and the oropharyngeal air column volume were determined and compared.

RESULTS

After the surgical intervention, it was found that the hyoid bone significantly moved to a more anterior (P = .028, P = .046), and superior (P = .028, P = .028) position. The preoperative mean oropharyngeal air column volume (618.88 ± 176.54 mm(3) ) also increased after infrahyoid muscle sectioning (797.01 ± 155.33 mm(3) ). and this change was also statistically significant (P = .028).

CONCLUSIONS

Infrahyoid release improves oropharyngeal air column volume, as the hyoid bone moves to a more anterior and superior position after this operation in an animal model. However, additional animal and human studies are necessary to evaluate a possible therapeutic role of this procedure.

LEVEL OF EVIDENCE

NA.

Distinct associations between hypertension and obstructive sleep apnea in male and female patients

Obstructive sleep apnea (OSA) is highly associated with hypertension. However, the correlation between hypertension and OSA at different levels of severity and the influence of gender on that correlation are unclear. A total of 996 patients (776 males and 190 females) with OSA were recruited. The influence of gender on the correlation between hypertension and OSA at different stratifications of severity, based on the apnea-hypopnea index (AHI), was fully evaluated together with the major health risk factors obesity, age, and diabetes. Females with OSA were significantly older on average than males with OSA. Moreover, females had milder degrees of OSA on average than the extent of severity seen in males. The proportion of females with diabetes or hypertension was higher than that of males. The proportion of males with hypertension and obesity increased significantly with OSA, and age also increased with OSA. The percentage of females with hypertension at different degrees of OSA severity was stable at about 26% in the mild, moderate, and severe OSA groups. Among females, age was increased significantly in the moderate relative to the mild OSA group. Moreover, the proportion of obese subjects was increased significantly in the severe compared with the moderate OSA group. The proportions of males and females with diabetes were not significantly different among all OSA severity groups. An ordinal multivariate logistic regression analysis confirmed that hypertension, age, and obesity were associated with OSA severity in males, whereas only age and obesity were associated with OSA severity in females. Although the proportion of subjects with hypertension was higher in females with OSA than in males with OSA, the proportion of subjects with hypertension increased as the severity of OSA increased in males but not in females.

The prevalence of obstructive sleep apnea-hypopnea syndrome-related symptoms and their relation to airflow limitation in an elderly population receiving home care

Background

Both airflow limitation and obstructive sleep apnea-hypopnea syndrome (OSAHS)-related symptoms are most prevalent in the elderly population. Previous studies revealed significant associations between OSAHS-related symptoms and obstructive airway diseases in the general population. However, other studies showed that the frequency of OSAHS-related symptoms in patients with obstructive airway diseases decreases after the age of 60 and older.

Aims

To investigate the prevalence of OSAHS-related symptoms (snoring, breathing pauses, and excessive daytime sleepiness [EDS]) and their relations to airflow limitation, for people over 65 years old.

Methods

A full screening spirometry program was performed in a total of 490 aging participants (mean age 77.5 years – range 65–98) who were attending 16 home care settings in central Greece. Airflow limitation was assessed according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometric criteria (FEV₁/FVC <70%). The Berlin Questionnaire and the Epworth Sleepiness Scale were used to screen individuals for OSAHS-related symptoms. Bivariate associations were described using odds ratio (OR) with 95% confidence intervals (CI).

Results

Airflow limitation prevalence was 17.1% (male 24.2% and female 9.9%) and was strongly related to male gender and smoking status. The prevalence rates of frequent snoring, breathing pauses, and EDS were 28.1%, 12.9%, and 11.6%, respectively. However, participants with airflow limitation were less likely to report breathing pauses, frequent snoring, EDS, and obesity. Finally, frequent snoring was significantly more common in males than females.

Conclusion

This study revealed decreased frequency of OSAHS-related symptoms in participants with airflow limitation suggesting that OSAHS-related symptoms and airflow limitation are not related in our elderly population.

Predictive factors for difficult mask ventilation in the obese surgical population

Background

Difficult Mask Ventilation (DMV), is a situation in which it is impossible for an unassisted anesthesiologist to maintain oxygen saturation >90% using 100% oxygen and positive pressure ventilation to prevent or reverse signs of inadequate ventilation during mask ventilation.  The incidence varies from 0.08 – 15%. Patient-related anatomical features are by far the most significant cause.  We analyzed data from an obese surgical population (BMI> 30 kg/m ²) to identify specific risk and predictive factors for DMV.

Methods

Five hundred and fifty seven obese patients were identified from a database of 1399 cases associated with preoperative airway examinations where mask ventilation was attempted. Assessment of mask ventilation in this group was stratified by a severity score (0-3), and a step-wise selection method was used to identify independent predictors.  The area under the curve of the receiver-operating-characteristic was then used to evaluate the model’s predictive value. Adjusted odds ratios and their 95% confidence intervals were also calculated.

Results

DMV was observed in 80/557 (14%) patients. Three independent predictive factors for DMV in obese patients were identified: age 49 years, short neck, and neck circumference  43 cm. In the current study th sensitivity for one factor is 0.90 with a specificity 0.35. However, the specificity increased to 0.80 with inclusion of more than one factor.

Conclusion

According to the current investigation, the three predictive factors are strongly associated with DMV in obese patients. Each independent risk factor alone provides a good screening for DMV and two factors substantially improve specificity. Based on our analysis, we speculate that the absence of at least 2 of the factors we identified might have a significant negative predictive value and can reasonably exclude DMV, with a negative likelihood ratio 0.81.

Investigating the association between obstructive sleep apnea and periodontitis

BACKGROUND

Obstructive sleep apnea (OSA) is a sleep disorder characterized by disruptions of normal sleep architecture. Chronic periodontitis is a chronic disease of the periodontium that elicits a general inflammatory response to local dental plaque. It has been suggested that periodontal disease may increase in severity with increasingly severe OSA because both disease entities share common inflammatory pathways, acting synergistically to alter the host response. The aim of this study is to analyze the association between severity of OSA and the prevalence/severity of periodontitis.

METHODS

One hundred patients from a large veterans administration sleep study center (n = 26 normal, n = 21 mild, n = 19 moderate, n = 34 severe) diagnosed with an overnight polysomnogram underwent a comprehensive periodontal examination. Periodontal parameters measured included the following: 1) mean periodontal probing depth (PD); 2) clinical attachment level (CAL); 3) gingival recession; and 4) percentage of sites with bleeding on probing, plaque, PD ≥5 mm, and CAL ≥3 mm.

RESULTS

Seventy-three percent of the sampled population had moderate/severe periodontal disease. χ(2) analyses revealed no significant differences in the prevalence of periodontal disease between the apnea-hypopnea index (AHI) groups, with a negligible Spearman correlation coefficient of 0.246 between AHI severity and periodontal disease severity categories. Analysis of covariance indicated a significant association between AHI severity categories and percentage of sites with plaque, after adjusting for age. Multivariable logistic regression analysis predicting moderate/severe periodontitis with AHI score, age, and smoking status indicated a significant association with age (P = 0.028) but no significant association with the other two predictors.

CONCLUSION

OSA was not significantly associated with the prevalence of moderate/severe periodontitis and the periodontal parameters examined, except percentage plaque.

A Matched Cohort Study of Postoperative Outcomes in Obstructive Sleep Apnea

Background:

Obstructive sleep apnea (OSA) is associated with increased risk of postoperative complications. The authors investigated whether preoperative diagnosis and prescription of continuous positive airway pressure therapy reduces these risks.

Methods:

Matched cohort analysis of polysomnography data and Manitoban health administrative data (1987 to 2008). Postoperative outcomes in adult OSA patients up to 5 yr before (undiagnosed OSA, n = 1,571), and any time after (diagnosed OSA, n = 2,640) polysomnography and prescription of continuous positive airway pressure therapy for a new diagnosis of OSA, were compared with controls at low risk of having sleep apnea (n = 16,277). Controls were matched by exact procedure, indication, and approximate date of surgery. Procedures used to treat sleep apnea were excluded. Follow-up was at least 7 postoperative days. Results were reported as odds ratio (95% CI) for OSA or subgroup versus controls.

Results:

In multivariate analyses, the risk of respiratory complications (2.08 [1.35 to 3.19], P &lt; 0.001) was similarly increased for both undiagnosed and diagnosed OSA. The risk of cardiovascular complications, primarily cardiac arrest and shock, was significantly different (P = 0.009) between undiagnosed OSA (2.20 [1.16 to 4.17], P = 0.02) and diagnosed OSA patients (0.75 [0.43 to 1.28], P = 0.29). For both outcomes, OSA severity, type of surgery, age, and other comorbidities were also important risk modifiers.

Conclusions:

Diagnosis of OSA and prescription of continuous positive airway pressure therapy were associated with a reduction in postoperative cardiovascular complications. Despite limitations in the data, these results could be used to justify and inform large efficacy trials of perioperative continuous positive airway pressure therapy in OSA patients.

Detection of sleep apnea by case-finding and home monitoring with Somnolter®: a pilot study

BACKGROUND

Obstructive sleep apnea and hypopnea syndrome (OSAHS) is a disorder that causes clinical symptoms (e.g. snoring, excessive daytime sleepiness and impaired concentration) that may increase the risk of traffic accidents, cardiovascular disease, type 2 diabetes and reduce the quality of life. A recently developed device (Somnolter®) detects apneas and hypopneas in a home setting, allowing to detect OSAHS in a more comfortable environment compared to the gold standard polysomnography. The aim of our study was to investigate whether the Somnolter® is useful in family practice to identify patients with OSAHS.

METHODS

Questionnaires were offered to patients in five general practitioner (GP) practices.Based on the questionnaire and body mass index, patients with an increased risk of OSAHS were contacted to collaborate in the study. In this convenience sample, 18 patients were successfully tested with the Somnolter® measuring SaO2, mandibular movements, body position, heart rate, nasal air flow and thoracic and abdominal breathing movements. The Somnolter® automatically analyses the data and different parameters to detect OSAHS. Afterwards, the data were manually revised by the researchers.

RESULTS

Out of 365 subjects, 31 met the inclusion criteria and 18 were successfully tested at home. Sixteen out of 18 patients had an Apnea Hypopnea Index (AHI) ≥ 5, ten of them had mild OSAHS, 3 were categorized as moderate OSAHS and finally 3 matched the criteria of severe OSAHS.

CONCLUSION

The proposed case-finding strategy still needs optimization, but is considered helpful in selecting patients at high risk of OSAHS. OSAHS was detected in 14 out of 18 patients tested with the Somnolter®. In the future the Somnolter® might be a feasible alternative to diagnose OSAHS.