Severity of obstructive sleep apnea: correlation with clinical examination and patient perception

The correlation between drug-induced sleep endoscopy findings and severity of obstructive sleep apnea

OBJECTIVE

This study aimed to assess the relationship between anthropometric data, drug-induced sleep endoscopy (DISE) findings, and severity of obstructive sleep apnea (OSA).

METHODS

From August 2016 to August 2017, a total of 147 surgically naïve adult patients with OSA underwent DISE. Factors that were analyzed included anthropometric data and DISE findings.

RESULTS

When anthropometric data and DISE findings were analyzed with AHI by univariate analysis, the results showed that Epworth Sleepiness Scale (ESS), body mass index (BMI), neck circumference, concentric collapse of the velum, lateral oropharyngeal collapse, and anterior-posterior collapse of the tongue base were considered potentially independent predictors (p = 0.024, p < 0 .001, p < 0 .001, p < 0.001, p < 0.001, p < 0 .001, respectively, by Spearman correlation). When all important factors were evaluated in a stepwise multiple linear regression analysis, BMI, lateral oropharyngeal collapse, and anterior-posterior collapse of the tongue base were identified as significant predictors for the severity of OSA. The final model was listed as below: AHI score = 2.19 BMI + 7.56 Oropharynx/Lateral degree + 8.23 Tongue base/ Anterior-Posterior degree - 40.59.

CONCLUSION

By analyzing anthropometric data and DISE findings with AHI score, the results indicated that BMI, lateral oropharyngeal collapse, and anterior-posterior collapse of the tongue base were important factors associated with the severity of OSA.

Predicting Severe Sleep Apnea in Patients with Complaints: Pulse Oximetry and Body Mass Index

Objective

An adequate evaluation combined with an easily accessible test would be a useful way to direct the appropriate patients to sleep centers in circumstances with a limited opportunity for polysomnography (PSG). For this reason, it is necessary to use a screening method prior to PSG evaluation. The aim of the present study was to investigate whether the use of body mass index (BMI) and pulse oximetry is sufficient to predict the severity of obstructive sleep apnea syndrome (OSAS) without PSG.

Methods

A total of 956 patients who were admitted to a tertiary referral center with complaints of witnessed apnea, excessive daytime sleepiness, and previously performed PSG were included in the study. Data of PSG (included pulse oximetry) and BMI were investigated for the determination of cut-off points for parameters in the patients.

Results

Based on the presence of severe OSAS, the cut-off points were ≥31.7 kg/m² for BMI, <81% for minimum oxygen saturation (Min O₂), and ≥14.1 min for sleep time with oxygen saturation <90% (ST₉₀). Severe OSAS risk was found to be higher in patients with BMI ≥31.7 kg/m², ST₉₀ ≥14.1 min, and Min O₂ ≤81% than in those without (OR: 37.173; 95% CI: 22.465-61.510, p=0.001). Specificity and accuracy were 94.85% and 72.49%, respectively, when all three cut-off scores were provided.

Conclusion

The appropriate cut-off values obtained from combining BMI and pulse oximetry data can provide accurate results for predicting the severity of OSAS.

The Relationship Between Modified Mallampati Score, Müller's Maneuver and Drug-Induced Sleep Endoscopy Regarding Retrolingual Obstruction

OBJECTIVES

This study explored the correlation between clinical explorations, including modified Mallampati score and Müller's maneuver, with drug-induced sleep endoscopy (DISE) findings regarding retrolingual obstruction.

METHODS

One hundred forty-two obstructive sleep apnea patients were enrolled in this prospective study. All of the patients received clinical explorations including modified Mallampati scoring and Müller's maneuver in the clinic. Drug-induced sleep endoscopy was further evaluated in the operating room.

RESULTS

A significant relationship was noted between modified Mallampati score and retrolingual obstruction during DISE. In contrast, no significant relationship was noted between Müller's maneuver and DISE findings regarding retrolingual obstruction.

CONCLUSIONS

A significant discrepancy existed between retrolingual airway collapse evaluated by modified Mallampati score and Müller's maneuver. Modified Mallampati score is more correlated with DISE regarding retrolingual obstruction compared to Müller's maneuver. It should therefore be used as an initial evaluation of retrolingual obstruction when DISE is unavailable.

Multi-level obstruction in obstructive sleep apnoea: prevalence, severity and predictive factors

OBJECTIVES

To characterise multi-level obstruction in terms of prevalence, obstructive sleep apnoea severity and predictive factors, and to collect epidemiological data on upper airway morphology in obstructive sleep apnoea patients.

METHODS

Retrospective review of 250 obstructive sleep apnoea patients.

RESULTS

On clinical examination, 171 patients (68.4 per cent) had multi-level obstruction, 49 (19.6 per cent) had single-level obstruction and 30 (12 per cent) showed no obstruction. Within each category of obstructive sleep apnoea severity, multi-level obstruction was more prevalent. Multi-level obstruction was associated with severe obstructive sleep apnoea (more than 30 events per hour) (p = 0.001). Obstructive sleep apnoea severity increased with the number of obstruction sites (correlation coefficient = 0.303, p < 0.001). Multi-level obstruction was more likely in younger (p = 0.042), male (p = 0.045) patients, with high body mass index (more than 30 kg/m2) (p < 0.001). Palatal (p = 0.004), tongue (p = 0.026) and lateral pharyngeal wall obstructions (p = 0.006) were associated with severe obstructive sleep apnoea.

CONCLUSION

Multi-level obstruction is more prevalent in obstructive sleep apnoea and is associated with increased severity. Obstruction at certain anatomical levels contributes more towards obstructive sleep apnoea severity.

Correlation of Lateral Cephalogram and Flexible Laryngoscopy with Sleep Study in Obstructive Sleep Apnea

Objective. To study the correlation between lateral cephalogram, flexible laryngoscopy, and sleep study in patients diagnosed with obstructive sleep apnea (OSA). Background. Screening tools should be devised for predicting OSA which could be performed on an outpatient basis. With this aim we studied the skeletal and soft tissue characteristics of proven OSA patients. Methods. A prospective study was performed in patients diagnosed with obstructive sleep apnea by sleep study. They were evaluated clinically and subjected to lateral cephalometry and nasopharyngolaryngoscopy. The findings were matched to see if they corresponded to AHI of sleep study in severity. An attempt was made to see whether the data predicted the patients who would benefit from oral appliance or surgery as the definitive treatment in indicated cases. Results. A retropalatal collapse seen on endoscopy could be equated to the distance from mandibular plane to hyoid (MP-H) of lateral cephalometry and both corresponded to severity of AHI. At the retroglossal region, there was a significant correlation with MP-H, length of the soft palate, and AHI. Conclusion. There is significant correlation of lateral cephalogram and awake flexible nasopharyngolaryngoscopy with AHI in OSA. In unison they form an excellent screening tool for snorers.

Drug-induced sedation endoscopy versus clinical exploration for the diagnosis of severe upper airway obstruction in OSAHS patients

BACKGROUND

Identifying the sites of obstruction of the upper airway in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) is paramount for surgical planning. The aim of this study is to compare wake physical exam findings to the ones obtained during drug-induced sedation endoscopy (DISE) in the diagnosis of severe collapse of the upper airway in OSAHS patients.

METHODS

A retrospective chart review of OSAHS patients who underwent DISE at our institution during the 2006-2010 period was conducted. All the patients had previously undergone a physical examination that included modified Mallampati index (MMI), the Müller maneuver (MM), and the Friedman staging system. Level and severity of airway collapse were evaluated. A severe collapse was attributed to obstructions equal or greater than 75 % of the airway.

RESULTS

A total of 138 patients were included in the study. The incidence of severe airway collapse was compared between DISE and MM; at retropalatal level, no significant difference was found. At retrolingual level, 69 % of patients had severe collapse with DISE in comparison to a 28 % with the MM (p < 0.05). No relationship was found either with the MMI or with the Friedman staging system when compared to the incidence of severe retrolingual collapse diagnosed by DISE. Concordance was low between awake and DISE exploration in both retropalatal and retroglossal level.

CONCLUSION

The Müller maneuver underestimates tongue base severe obstruction diagnosis when compared to that obtained after DISE in OSAHS patients. The wake patient exploration does not accurately correlate to DISE exploration.

Friedman tongue position: age distribution and relationship to sleep-disordered breathing

PURPOSE

Friedman tongue position (FTP) may play an important role in the evaluation of children with sleep-related breathing disorders (SRBD), but there are no previous data on FTP distribution by age. The objective of the current study was to determine the distribution of FTP by age and examine the relationship between FTP and snoring in children.

METHODS

Prospective cross-sectional study of 199 children (mean age, 6.8 years; 59% male) had tongue position assessed by FTP as part of their clinical examination of the oral cavity during routine ENT visits at a tertiary care children's hospital. The FTP and snoring frequency of participants was examined across the entire age range as well as by comparing those older (middle childhood and above) and younger than 5 years of age.

RESULTS

Tongue position did not correlate with age or snoring frequency. The proportion of children with FTP III/IV was not significantly different in children younger than five years of age compared to older than five. Habitual snoring was not associated with having a higher FTP. Among children who snored <3 times per week, those who had previously undergone tonsillectomy did have higher FTP compared to those who had not (p=0.007). BMI-%-for-age was significantly correlated with FTP (p=0.003). The percent of children having FTP class III/IV differed significantly between ethnicities (22% of whites, 26% of others, 45% of hispanics, 53% of African-Americans; p=0.011). Inter-rater reliability among pediatric otolaryngologist was excellent (kappa=0.93, p<0.001).

CONCLUSIONS

There does not appear to be an association between FTP with age or snoring frequency in children. The excellent inter-rater reliability for FTP among pediatric ENT providers suggests the null findings are not due to rater bias. These findings may serve as an important reference for those studying the role of tongue position in pediatric SRBD and complement previous studies examining FTP among children with known OSA or snoring.

Validation of overnight oximetry to diagnose patients with moderate to severe obstructive sleep apnea

Background

Polysomnography (PSG) is treated as the gold standard for diagnosing obstructive sleep apnea (OSA). However, it is labor-intensive, time-consuming, and expensive. This study evaluates validity of overnight pulse oximetry as a diagnostic tool for moderate to severe OSA patients.

Methods

A total of 699 patients with possible OSA were recruited for overnight oximetry and PSG examination at the Sleep Center of a University Hospital from Jan. 2004 to Dec. 2005. By excluding 23 patients with poor oximetry recording, poor EEG signals, or respiratory artifacts resulting in a total recording time less than 3 hours; 12 patients with total sleeping time (TST) less than 1 hour, possibly because of insomnia; and 48 patients whose ages less than 20 or more than 85 years old, data of 616 patients were used for further study. By further considering 76 patients with TST < 4 h, a group of 540 patients with TST ≥ 4 h was used to study the effect of insufficient sleeping time. Alice 4 PSG recorder (Respironics Inc., USA) was used to monitor patients with suspected OSA and to record their PSG data. After statistical analysis and feature selection, models built based on support vector machine (SVM) were then used to diagnose moderate and moderate to severe OSA patients with a threshold of AHI = 30 and AHI = 15, respectively.

Results

The SVM models designed based on the oxyhemoglobin desaturation index (ODI) derived from oximetry measurements provided an accuracy of 90.42-90.55%, a sensitivity of 89.36-89.87%, a specificity of 91.08-93.05%, and an area under ROC curve (AUC) of 0.953-0.957 for the diagnosis of severe OSA patients; as well as achieved an accuracy of 87.33-87.77%, a sensitivity of 87.71-88.53%, a specificity of 86.38-86.56%, and an AUC of 0.921-0.924 for the diagnosis of moderate to severe OSA patients. The predictive outcome of ODI to diagnose severe OSA patients is better than to diagnose moderate to severe OSA patients.

Conclusions

Overnight pulse oximetry provides satisfactory diagnostic performance in detecting severe OSA patients. Home-styled oximetry may be a tool for severe OSA diagnosis.

The impact of modified tongue base suspension on CPAP levels in patients with severe OSA

The aim of this study was to evaluate the effects of modified tongue base suspension (mTBS) procedure on continuous positive airway pressure (CPAP) levels in patients with severe obstructive sleep apnea (OSA). From November 2011 to December 2012, a total of 31 patients with severe OSA who underwent mTBS were included into this prospective case series with planned data collection. Prior to surgery, all the patients were subjected to a polysomnography (PSG) and CPAP titration on two separate nights. Following the surgery, patients were subjected to a control PSG and CPAP titration at the sixth month of follow-up period. The preoperative and postoperative mean apnea hypopnea index (AHI), CPAP titration values, AHI during CPAP use and amount of sleeping time with CPAP were compared. Median age was 48 years (range 31-66), and most patients were male (87.0 %). Postoperative mean AHI (44.73 ± 17.05 vs. 19.96 ± 19.52), optimal CPAP value (12.64 ± 1.60 vs. 8.00 ± 1.77) and AHI during CPAP use (3.79 ± 1.78 vs. 2.25 ± 1.81) were decreased, and the amount of sleeping time with CPAP (5.29 ± 0.84 vs. 6.52 ± 0.89) was increased significantly (p < 0.001 for all parameters). The surgery was considered to be successful when 50 % reduction in the mean AHI and/or the decrease of AHI below 20/h were obtained. A total of 24 patients (77.4 %) met the surgical success criteria. The mTBS is a safe and feasible procedure with favorable effects on CPAP levels in patients with severe OSA.

Quality of Life Measures Following Laser Assisted Uvulopalatopharyngoplasty (LAUP) in Obstructive Sleep Apnoea Syndrome (OSAS)

The objective of this study is to assess the efficacy of laser assisted uvulopalatopharyngoplasty in the treatment of Obstructive Sleep Apnoea Syndrome. This study was conducted over a period of 2 years and comprised of a total of 18 patients of both sexes, from a pool of 64 patients who presented with clinical features of OSAS. All the surgeries were done by the same surgeon and standardised criteria for diagnosis was followed. Only those Patients who were diagnosed to have moderate to severe OSAS of the obstructive type with single level retro palatal obstruction were treated surgically with LAUP, and followed up for a period of 6 months. Of the 18 patients 16 reported of improvement in quality of life, as assessed by Functional Outcomes of Sleep Questionnaire (FOSQ), accounting for 88.8%. The results support the surgical treatment for OSAS of moderate to severe single level retro palatal type, as evidenced by the FOSQ scoring. LAUP is a very good surgical option in alleviating the symptoms of moderate to severe single level retro palatal OSAS.

The Relation of the Obstruction Site on Muller's Maneuver with BMI, Neck Circumference and PSG Findings in OSAS

We investigated relation of the site of obstruction detected on Muller maneuver (MM) with polysomnography (PSG) and physical examination findings. Data of 703 patients admitted to Ankara Numune Education and Research Hospital Sleep Laboratory between 2008 and 2013 were analyzed retrospectively; 394 patients with apnea-hypopnea indexes (AHI) ≥5/h were included. Site of collapse on MM was determined at retrolingual level at anteroposterior (M1) and lateral-lateral (M2) directions; at retropalatal level at anteroposterior (M3) and lateral-lateral (M4) directions. There were 125 (31.7 %) females and 269 (68.3 %) males. BMI had significant positive correlations with M2 (p < 0.001) and M4 (p = 0.002) scores, ESS (p = 0.013) and AHI (p = 0.001). AHI had significant positive correlations with ESS (p = 0.003), M2 (p < 0.001), M3 (p = 0.037) and M4 (p < 0.001) scores and NC (p = 0.001). Minimum oxygen saturation had significant reverse correlations with M1 (p = 0.046), M2 (p < 0.001), M3 (p = 0.003), M4 (p < 0.001), AHI (p < 0.001), ESS (p = 0.003) and BMI (p = 0.001). In OSAS patients, increased BMI, NC and AHI are correlated with lateral pharyngeal wall (LPW) collapse in retropalatal and retrolingual levels on MM. LPW collapse is more valuable to predict OSAS compared to anteroposterior collapse. LPW collapse on MM may be used as a selection criterion for ordering PSG. Further studies are needed to better clarify importance of LPW in OSAS surgery.

Diagnostic Value of the Friedman Tongue Position and Mallampati Classification for Obstructive Sleep Apnea

Objective

To assess the association between the Mallampati classification and Friedman tongue position for obstructive sleep apnea severity as determined by apnea-hypopnea index and to determine which method is most closely correlated with prediction of obstructive sleep apnea severity.

Data Sources

English-language searches of PubMed, MedLine, and the Cochrane database. Reference sections of identified studies were examined for additional articles.

Review Methods

Databases through December 2011 were searched, combined with review of relevant article bibliographies, and assessed by 4 reviewers. Systematic review and random-effects meta-analysis of studies evaluating tongue position and obstructive sleep apnea severity were performed. Outcomes were reported as correlations.

Results

Ten studies met inclusion criteria and had data for pooling (2513 patients). Friedman tongue position and Mallampati classification were significantly associated with obstructive sleep apnea severity, with a correlation of 0.351 (0.094-0.564, P = .008). Analysis of the correlation of tongue position with obstructive sleep apnea severity reveals correlations of 0.184 (0.052, 0.310, P = .006) and 0.388 (0.049, 0.646, P = .026) for the Mallampati classification and Friedman tongue position, respectively. Publication bias does not yield a significant Egger regression intercept; however, 4 imputed values to the right of the mean were found using Duval and Tweedie’s trim-and-fill method, yielding an overall correlation of 0.498 (confidence interval = 0.474-0.521).

Conclusion

The Mallampati classification and Friedman tongue position assessment techniques are significantly correlated with predicting obstructive sleep apnea severity. Publication bias does not significantly affect our results. The strength of this correlation is higher for Friedman tongue position, although 95% confidence intervals for the respective correlation coefficients overlap.

Is the population properly informed about sleep disorders?

OBJECTIVE: To measure the prior knowledge about sleep disorders and patient's ability to report their problems adequately to health professionals. METHODS: We analyzed 208 patient's records and extracted the following information: date of birth, gender, medical diagnostic hypotheses, patient's primary complaint in their words, considering the most appropriated semantic approximation to the perceptual phenomena, either by their own or by reasoning information from the partner. We compared the agreement (Kappa's test) between patient's complaint and medical diagnosis. The 95% confidence interval was used to analyze proportions. RESULTS: We found strong correlations for bruxism; moderate for snoring, insomnia, nightmares, somniloquy, and restless legs syndrome; fair for excessive movement during sleep (EMDS) and obstructive sleep apnea syndrome (OSA). CONCLUSIONS: The observed correlations were heterogeneous, but important diseases such as OSA and EMDS in children showed fair and weak correlations. This suggests an unsatisfactory knowledge level among the population about these disorders, despite their high prevalence and impact on patient's overall health.

Investigation of lateral pharyngeal walls in OSAS

The aim of this study is to investigate the relationship between the site of obstruction detected on Müller's maneuver and the polysomnography findings in patients with obstructive sleep apnea syndrome. This study is a prospective cohort study in a setting of Tertiary referral center. The study was performed on 87 patients (59 males and 28 females) with a mean age of 50 ± 10.34 years (range 20-83 years) who presented with the complaints of snoring, apnea, witnessed apnea and daytime sleepiness. The height and body weight of the enrolled patients were measured and the body mass indexes were calculated. The obstruction degrees of the soft palate and lateral pharyngeal walls at the level of the soft palate and the obstruction degrees of the tongue base and lateral pharyngeal walls at the level of the tongue base were determined using the Müller's maneuver. All patients underwent whole-night polysomnography at our hospital's Sleep Center. The apnea-hypopnea index values of the patients increased as their ages and body mass index values increased. There was a highly statistically significant correlation between apnea-hypopnea index and the obstruction degree of the lateral pharyngeal walls at the level of the tongue base on Müller's maneuver (p < 0.01). We found that the apnea-hypopnea index increased as the obstruction degree of the lateral pharyngeal walls increased on Müller's maneuver. In patients with obstructive sleep apnea syndrome, a high apnea-hypopnea index can be predicted if the obstruction degree of the lateral pharyngeal walls is high at the level of the tongue base on Müller's maneuver.

The correlation between pharyngeal narrowing and the severity of sleep-disordered breathing

OBJECTIVE: The aim of this study was to examine the correlation between the degree or shape of pharyngeal narrowing as observed during the Muller maneuver and the severity of sleep-disordered breathing (SDB).

SUBJECTS AND METHODS: We enrolled 33 patients with SDB, and they underwent polysomnography (PSG). The degree of pharyngeal narrowing (grade I-IV) according to fiberoptic nasopharyngoscopy with the Muller maneuver (FNMM) and the shape of pharyngeal narrowing were evaluated at different anatomical levels. These variables were compared with the total apnea hypopnea index (AHI), the supine AHI, and the lateral AHI obtained by PSG.

RESULTS: The retroglossal FNMM grades revealed significant correlation with total AHI ( P = 0.030) and supine AHI ( P = 0.012). The retropalatal FNMM grades were significantly correlated with lateral AHI ( P = 0.020). The lateral-narrowing type at the retropalatal level is more significantly associated with higher total AHI compared with the anteroposterior-narrowing type ( P = 0.010).

CONCLUSION: The anatomic level and the degree of pharyngeal narrowing observed during FNMM revealed a correlation with the AHIs of different sleeping positions.