Screening for obstructive sleep apnea syndrome in patients with type 2 diabetes mellitus: a prospective study on sensitivity of Berlin and STOP-Bang questionnaires

A Narrative Review of Sex and Gender Differences in Sleep Disordered Breathing: Gaps and Opportunities

INTRODUCTION

Sleep disordered breathing (SDB) is a common condition, associated with multiple comorbidities including cardiovascular and metabolic disease. It has been previously established that SDB is more prevalent in men than women, shifting the literature's focus away from the latter population. As such, underdiagnosis, and thus undertreatment, of SDB in women exists.

METHODS

To establish the differences in prevalence, clinical presentation, and pathophysiology of SDB between the two sexes, a narrative review of the current literature was performed.

RESULTS

Rates of SDB are higher among men, likely driven by differences in symptom presentation between men and women, with women presenting with more "atypical" symptoms, and lack of sensitivity in SDB screening tools to detect SDB in women. In addition to the cardiovascular risks of SDB, women with SDB may have worse quality of life, higher prevalence of insomnia, and respiratory issues.

DISCUSSION

More research is needed to better define the unique pathophysiology and clinical presentation of SDB in women. In addition, an increased awareness among health care providers and the lay public of the SDB-specific sex and gender differences will serve to minimize disparities in identification and treatment of SDB in women.

Associations of Chronic Diabetes Complications and Cardiovascular Risk with the Risk of Obstructive Sleep Apnea in Patients with Type 2 Diabetes

Background: Type 2 diabetes mellitus (T2DM) is associated with increased mortality and morbidity, including cardiovascular diseases and obstructive sleep apnea (OSA). The aim of this study was to assess the associations between cardiovascular risk, chronic diabetes complications and the risk of OSA in adult patients with T2DM. Methods: The study included 529 patients with T2DM in whom moderate-to-severe OSA risk was assessed using the STOP-Bang questionnaire, dividing the subjects into two groups: group 1: STOP-Bang score <5, and group 2: STOP-Bang score ≥5, respectively. In all the subjects, cardiovascular risk was assessed using the UKPDS risk engine. Statistical analysis was performed using SPSS 26.0, the results being statistically significant if p value was <0.05. Results: 59% of the subjects scored ≥5 on the STOP-Bang questionnaire. We recorded statistically significant differences between the two groups regarding diabetes duration, HbA1c, HOMA-IR, albuminuria, as well as cardiovascular risk at 10 years for both coronary heart disease (CHD) and stroke (p < 0.05). Furthermore, through logistic regression, adjusting for confounding factors, we demonstrated that the STOP-Bang score ≥ 5 is a risk factor for 10-year fatal and nonfatal CHD risk. Conclusions: It is extremely important to screen and diagnose OSA in patients with T2DM, in order to improve the primary and secondary prevention of cardiovascular events in these patients.

The prevalence of obstructive sleep apnea in patients with type 2 diabetes: a systematic review and meta-analysis

Background

Obstructive Sleep Apnea (OSA) is one of the diseases related to diabetes. Considering the varying prevalence of OSA in patients with type 2 diabetes in different parts of the world, in order to aggregate the results and come to a general review about the topic mentioned, the current study performed a systematic review and meta-analysis of OSA in patients with type 2 diabetes.

Methods

In this study, the international databases (PubMed, Scopus, Web of science, and Cochran library) were searched without time limit using keywords diabetes, obstructive sleep apnea, and prevalence or epidemiology. Homogeneity was investigated among studies using Cochran Q test and I2 index. Given the heterogeneity of studies, random effect model was used to estimate the prevalence of OSA. Meta-regression was used to investigate the effect of quantitative variables on the prevalence of OSA. Comprehensive Meta-analysis (CMA) software was used for data analysis.

Results

Twenty studies were included in the meta-analysis. In these 19 studies, the total number of patients with type 2 diabetes was 10,754, with a mean age of 58.6 ± 4.1 years. Final estimation of OSA prevalence was calculated to be 56.0%. The results of meta-regression showed the prevalence of OSA increased with a rise in the mean age, the percentage of male sex, body mass index, and sample size.

Conclusion

Given the high prevalence of OSA in patients with type 2 diabetes, weight control can partly mitigate their problems and possibly reduce OSA prevalence.

Validation of the STOP questionnaire as a screening tool for OSA among different populations: a systematic review and meta-regression analysis

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a sleep breathing disorder associated with adverse health outcomes, but it remains largely underdiagnosed. The STOP questionnaire is a simple tool for screening OSA and is widely used in various populations. The objective of this study was to determine the predictive parameters of the STOP questionnaire to detect OSA in sleep clinics, medical population, surgical population, commercial drivers, and the general population.

METHODS

Electronic databases were searched from January 2008 to April 2021. Pooled predictive parameters were recalculated using 2 × 2 contingency tables and random-effects meta-analyses were performed. The combined test characteristics at different OSA severities [any OSA (AHI≥5), moderate-to-severe OSA (AHI≥15), severe OSA (AHI≥30)] were used to compare the accuracy of the STOP questionnaire with polysomnography. The quality of the studies was evaluated using Cochrane Methods criteria.

RESULTS

Twenty-four studies met the inclusion criteria: 16 were in the sleep clinic population (n=8,132), four in medical population (n=1,023), two in the surgical population (n=258), and one study each on commercial drivers (n=85) and general population (n=4,770). A STOP score ≥2 showed excellent sensitivity to the different OSA severities for the sleep clinic population (>89%) and to severe OSA for the medical population (85.6%). In both populations, the STOP questionnaire also had excellent discriminative power to exclude severe OSA [negative predictive values (NPV) >84%]. The pooled sensitivity and NPV for the surgical population with moderate-to-severe OSA was 81% and 75%.

CONCLUSIONS

This meta-analysis suggests that the STOP questionnaire is a valid and effective screening tool for OSA among these population.

Use of the pictorial Sleepiness and Sleep Apnoea Scale in Chinese patients with suspected obstructive sleep apnoea syndrome

Background

Sleep related breathing disorders represent a significant health burden. Being able to stratify patients according to their need for differing types of investigation and predicting the likelihood of obstructive sleep apnoea syndrome (OSAS) is helpful. This study attempts to assess the value of a pictorial Sleepiness and Sleep Apnoea Scale (pSSAS) in this process.

Methods

A total of 126 sequential patients attending a sleep service with suspected OSAS completed the pSSAS, the Epworth Sleepiness Score (ESS), and the Berlin Questionnaire (BQ) prior to full polysomnography.

Results

With Apnoea-hypopnea index (AHI) >15 as the positive diagnostic criterion, the area under the receiver operating characteristic curve (AUC) of the BQ was the highest (0.683), followed by pSSAS and ESS (AUC 0.648 and 0.516, respectively). With AHI >30 as the positive diagnostic criterion, the AUC of pSSAS was the highest (0.696), followed by BQ and ESS (AUC 0.653 and 0.510, respectively). With MiniSO₂ <80% as the positive diagnostic criterion, the AUC of pSSAS was the highest (0.736), followed by BQ and ESS (AUC 0.634 and 0.516, respectively).

Conclusions

This study shows that the pSSAS which was first tested in a European population performs equally well amongst a Chinese population. The pSSAS performed in a similar fashion to the BQ in predicting those likely to have OSAS and was superior at predicting those who have severe OSAS. Because it is a pictorial questionnaire, it has advantages for those who may have reduced health literacy, a problem which is under-recognized in most healthcare systems.

Predictive Value of Clinical and Questionnaire Based Screening Tools of Obstructive Sleep Apnea in Patients With Type 2 Diabetes Mellitus

Background

Obstructive sleep apnea (OSA) is a major health problem for people with type 2 diabetes mellitus (DM2) and is associated with poorer glycemic control. Early detection is critical to proper management. In this study, we planned to assess and compare the diagnostic accuracy of various OSA screening tools in patients with DM2.

Methods

In this cross-sectional study, we consecutively recruited 58 patients with DM2, presenting to the endocrinology department of Services Hospital Lahore between February 2020 to March 2021. Along with demographic and anthropometric measurements, including BMI and neck circumference, participants answered the snoring, tiredness, observed apnea, high blood pressure - BMI, age, neck circumference, and gender (STOP-BANG) questionnaire, Berlin questionnaire, and Epworth sleepiness scale. All participants then underwent an overnight, level 3 polysomnography.

Results

The overall prevalence of OSA, diagnosed by overnight polysomnography, was 65.5% in type 2 diabeticDM2 patients. The STOP-BANG questionnaire had the highest sensitivity for mild, moderate, and severe OSA i.e., 84.2%, 90.3%, and 100% respectively. Berlin questionnaire also had 100% sensitivity for severe OSA and was most specific for mild and moderate OSA (70% and 63% respectively) whereas the Epworth sleepiness scale had the highest specificity of 53.3% for severe OSA.

Conclusion

This study shows that OSA is highly prevalent in DM2 patients in Pakistan. The STOP-BANG and Berlin questionnaire proved to be effective screening tools, especially for severe OSA. Results of our study should encourage the routine use of these questionnaires in clinical practice, to help in the early identification of OSA in diabetics.

Sleepiness Behind the Wheel and the Implementation of European Driving Regulations

Sleep disturbance and sleepiness are established risk factors for driving accidents and obstructive sleep apnea (OSA) is the most prevalent medical disorder associated with excessive daytime sleepiness. Because effective treatment of OSA reduces accident risk, several jurisdictions have implemented regulations concerning the ability of patients with OSA to drive, unless effectively treated. This review provides a practical guide for clinicians who may be requested to certify a patient with OSA as fit to drive regarding the scope of the problem, the role of questionnaires and driving simulators to evaluate sleepiness, and the benefit of treatment on accident risk.

Validation of the STOP-Bang questionnaire as a screening tool for obstructive sleep apnoea in patients with cardiovascular risk factors: a systematic review and meta-analysis

Introduction

Obstructive sleep apnoea (OSA) is highly prevalent in patients with cardiovascular risk factors and is associated with increased morbidity and mortality. This review presents the predictive parameters of the STOP-Bang questionnaire as a screening tool for OSA in this population.

Methods

A search of databases was performed. The inclusion criteria were: (1) use of the STOP-Bang questionnaire to screen for OSA in adults (>18 years) with cardiovascular risk factors; (2) polysomnography or home sleep apnoea testing performed as a reference standard; (3) OSA defined by either Apnoea–Hypopnoea Index (AHI) or Respiratory Disturbance Index; and (4) data on predictive parameters of the STOP-Bang questionnaire. A random-effects model was used to obtain pooled predictive parameters of the STOP-Bang questionnaire.

Results

The literature search resulted in 3888 articles, of which 9 papers met the inclusion criteria, involving 1894 patients. The average age of the included patients was 58±13 years with body mass index (BMI) of 30±6 kg/m², and 64% were male. The STOP-Bang questionnaire has a sensitivity of 89.1%, 90.7% and 93.9% to screen for all (AHI ≥5), moderate-to-severe (AHI ≥15) and severe (AHI≥30) OSA, respectively. The specificity was 32.3%, 22.5% and 18.3% and the area under the curve (AUC) was 0.86, 0.65 and 0.52 for all, moderate-to-severe and severe OSA, respectively.

Conclusion

The STOP-Bang questionnaire is an effective tool to screen for OSA (AHI≥5) with AUC of 0.86 in patients with cardiovascular risk factors.

European Respiratory Society statement on sleep apnoea, sleepiness and driving risk

Obstructive sleep apnoea (OSA) is highly prevalent and is a recognised risk factor for motor vehicle accidents (MVA). Effective treatment with continuous positive airway pressure has been associated with a normalisation of this increased accident risk. Thus, many jurisdictions have introduced regulations restricting the ability of OSA patients from driving until effectively treated. However, uncertainty prevails regarding the relative importance of OSA severity determined by the apnoea–hypopnoea frequency per hour and the degree of sleepiness in determining accident risk. Furthermore, the identification of subjects at risk of OSA and/or accident risk remains elusive. The introduction of official European regulations regarding fitness to drive prompted the European Respiratory Society to establish a task force to address the topic of sleep apnoea, sleepiness and driving with a view to providing an overview to clinicians involved in treating patients with the disorder. The present report evaluates the epidemiology of MVA in patients with OSA; the mechanisms involved in this association; the role of screening questionnaires, driving simulators and other techniques to evaluate sleepiness and/or impaired vigilance; the impact of treatment on MVA risk in affected drivers; and highlights the evidence gaps regarding the identification of OSA patients at risk of MVA.

Are the International Classification of Functioning, Disability and Health (ICF) domains considered in the obstructive sleep apnea instruments? An integrative review

PURPOSE

Obstructive Sleep Apnea (OSA) is related to cardiovascular, metabolic, and neurocognitive diseases. Furthermore, OSA symptoms, such as excessive sleepiness, fatigue, and mood disorders, may interfere in functioning. The assessment of this aspect in patients with OSA is not frequent and no specific instrument is available in the literature. Our aim is to identify if the International Classification of Functioning, Disability and Health (ICF) domains are considered in the validated instruments used to assess patients with OSA.

METHODS

In this integrative literature review, three databases were searched: Pubmed, Embase, and LILACS. Bibliographic survey was carried out in 2020, between March and July. Articles published in English, Portuguese, and Spanish with validated tools to assess OSA in adults were included.

RESULTS

Thirty instruments have undergone a process of concept extraction and coding according to the ICF, generating a total of 769 significant concepts. It was observed that the function domain was the most prevalent, making 42% (n = 323) of the concepts, followed by domains of activity (16%), participation (10%), environmental factors (5%), personal factor (5%), and structure (1%). Only one instrument, the "Sleep Apnea Quality of Life Index (SAQLI)," encompasses all domains of the ICF in its constructs.

CONCLUSION

In the analyzed instruments, the function domain prevails, with most concepts related to sleep functions. Only one validated instrument included in this research covered all the ICF domains. This instrument closely matched the recommended way of assessing functioning, though it approached the domains in an unbalanced way.

Exploring the STOP-BANG questionnaire for obstructive sleep apnea screening in seniors

STUDY OBJECTIVES

The accuracy of obstructive sleep apnea (OSA) screening instruments in seniors may change as the predictive role of sex, age, and body mass index (BMI) changes with aging. We investigated the diagnostic performance of the STOP-BANG questionnaire in older individuals with aging-adapted scores and thresholds.

METHODS

Independent community-dwelling adults aged 65 years or older were screened for OSA. The STOP-BANG questionnaire was tested with different configurations and compared to the apnea-hypopnea index (AHI) obtained from home sleep apnea testing (HSAT). Epworth Sleepiness Scale (ESS) and Athens Insomnia Scale (AIS) were tested as possible supplementary screening criteria.

RESULTS

We recruited 458 individuals with a mean age of 71 ± 5 years, 41% men, BMI of 28.5 ± 4.6 kg/m². Mild, moderate, and severe OSA were present in, respectively, 34%, 30%, and 19% of the sample. The STOP questions had an area under the curve (AUC) of the receiver operating characteristic curve significantly lower than the STOP-BANG and the STOP+BMI > 28 kg/m² (STOP-B28). Both STOP-BANG and STOP-B28 had high sensitivity and low specificity in all OSA levels with similar AUC to predict AHI ≥ 5 events/h, 0.64. ESS and AIS were nonsignificant as adjunctive instruments.

CONCLUSIONS

Novel modifications of a standard instrument created the STOP-B28, a simpler-to-obtain and similarly performing variation of the STOP-BANG using fewer inputs, and useful to exclude OSA. Screening seniors via questionnaires to detect OSA is problematic. Considering the 83% OSA prevalence in this age group, it may be a sensible option to indicate objective tests, oximetry, HSAT, or even polysomnography, as a first step in OSA investigation.

Gender Differences in Obstructive Sleep Apnea: The Value of Sleep Questionnaires with a Separate Analysis of Cardiovascular Patients

Background: Gender affects the clinical presentation of obstructive sleep apnea (OSA). The classic OSA symptoms, such as sleepiness, snoring, and apnea, are not so frequent in women. Objectives: To evaluate possible gender differences in questionnaires used for OSA prediction, such as the Epworth Sleepiness Scale (ESS), STOP, STOP Bang (SB), Berlin Questionnaire (BQ), Athens Insomnia Scale (AIS), and Fatigue Scale (FS). Methods: 350 males were matched with 350 women referred to a sleep clinic, according to OSA severity. All responded to the questionnaires and underwent a sleep study. Cardiovascular disease (CVD) patients were separately analyzed. Results: ESS did not differ between genders. SB was higher in males, whereas STOP, BQ, AIS, and FS were higher in females. BQ presented the highest sensitivity in both genders, whereas STOP exhibited the highest specificity in males and ESS in females. AIS and FS were more sensitive and SB more specific in females, whereas BQ was more specific in males. For severe OSA, the predictive values of SB and BQ were almost similar for both genders; however AIS and FS were higher in women. CVD patients presented higher scores, independent of gender, except for AIS, which was higher in females. Conclusion: Gender-specific evaluation of questionnaires is necessary to prevent OSA under-diagnosis.

Sleep questionnaires for the screening of obstructive sleep apnea in patients with type 2 diabetes mellitus compared with non-diabetic patients

BACKGROUND

Several tools have been used to screen for obstructive sleep apnea (OSA). Evaluation of the predictive performance of different questionnaires is essential in patients with type 2 diabetes mellitus (T2DM) because the prevalence of OSA in this population is high. The aim of this study was to evaluate different sleep questionnaires to identify T2DM patients with OSA, and to compare the predictive values of these questionnaires with a matched sample of non-diabetic patients.

METHODS

The study was a retrospective study of two patients groups (n = 350 with T2DM, n = 350 without T2DM) visiting a sleep clinic and matched by age, gender, body mass index, and the apnea-hypopnea index (AHI). Symptoms of OSA and Epworth Sleepiness Scale (ESS), STOP-Bang, Berlin questionnaire, and Athens insomnia scale (AIS) scores were compared, and sleep studies were performed.

RESULTS

Diabetic patients with OSA complained more frequently of nocturia (P = 0.025), morning headaches (P = 0.04), restless sleep (P = 0.002), and leg movements (P = 0.01) than non-diabetic patients with OSA. Most predictive values of the sleep questionnaires did not differ significantly between the two groups; however, the AIS was higher only in T2DM women (P = 0.01). In both groups, the Berlin and STOP-Bang questionnaires had the highest sensitivity. The ESS had the highest specificity in T2DM patients and the STOP and S-B questionnaires had the highest specificity in non-diabetics.

CONCLUSIONS

The predictive performance of the questionnaires was similar in both groups, especially in the case of moderate and severe OSA.

The STOP-Bang and Berlin questionnaires to identify obstructive sleep apnoea in Alzheimer's disease patients

BACKGROUND

A close relationship between obstructive sleep apnoea (OSA) and Alzheimer's disease (AD) has been described in recent years. OSA is a risk factor for AD, but the diagnosis and clinical characteristics of OSA in patients with AD is not well understood. This study evaluated the clinical utility of two screening questionnaires, the STOP-Bang questionnaire (SBQ) and the Berlin questionnaire (BQ), to identify which patients with mild AD are at higher risk of having OSA and to determine the clinical predictors of OSA in this population.

METHODS

In this study, 91 consecutive outpatients with mild AD were prospectively evaluated with the SBQ and the BQ. All patients underwent level 1 in-laboratory polysomnography. The predictive performance of the questionnaires were calculated for different apnoea-hypopnoea index (AHI) cut-offs.

RESULTS

The median age of the patients was 76.0 (73.0; 80.0) years, and 58 (63.7%) were female. Of those, 81 patients (89.02%) were found to have OSA defined by an AHI > 5 events/h. Comparing the predictive performances of the SBQ and the BQ, the SBQ was found to have a higher diagnostic sensitivity (85% vs 4%), a lower specificity (35% vs. 96%), a higher positive predictive value (PPV) (44% vs 33%) and negative predictive value (NPV) (80% vs 65%) for detecting severe OSA at an AHI cut-off of 30 events/h. None of the items alone in the two questionnaires predicted the risk of OSA. A modified version of the SBQ, with new cut-off points for several variables according to the characteristics of AD patients, showed a slightly greater AUC than the standard SBQ (AUC 0.61 vs 0.72).

CONCLUSION

There is a high prevalence of OSA among patients with mild AD. The SBQ and the BQ are not good screening tools for detecting OSA in patients with AD. A modified version of SBQ could increase the detection of these patients.

Association of sleep problems with neuroendocrine hormones and coagulation factors in patients with acute myocardial infarction

Background

Obstructive sleep apnea (OSA) and insomnia are frequent sleep problems that are associated with poor prognosis in patients with coronary heart disease. The mechanisms linking poor sleep with an increased cardiovascular risk are incompletely understood. We examined whether a high risk of OSA as well as insomnia symptoms are associated with neuroendocrine hormones and coagulation factors in patients admitted with acute myocardial infarction.

Methods

We assessed 190 patients (mean age 60 years, 83% men) in terms of OSA risk (STOP screening tool for the assessment of high vs. low OSA risk) and severity of insomnia symptoms (Jenkins Sleep Scale for the assessment of subjective sleep difficulties) within 48 h of an acute coronary intervention. Circulating concentrations of epinephrine, norepinephrine, cortisol, fibrinogen, D-dimer, and von Willebrand factor were measured the next morning. The association of OSA risk and insomnia symptoms with neuroendocrine hormones and coagulation factors was computed using multivariate models adjusting for demographic factors, health behaviors, somatic and psychiatric comorbidities, cardiac disease-related variables, and OSA risk in the model for insomnia symptoms, respectively, for insomnia symptoms in the model for OSA risk.

Results

High OSA risk was identified in 41% of patients and clinically relevant insomnia symptoms were reported by 27% of patients. Compared to those with low OSA risk, patients with high OSA risk had lower levels of epinephrine (p = 0.015), norepinephrine (p = 0.049) and cortisol (p = 0.001). More severe insomnia symptoms were associated with higher levels of fibrinogen (p = 0.037), driven by difficulties initiating sleep, and with lower levels of norepinephrine (p = 0.024), driven by difficulties maintaining sleep.

Conclusions

In patients with acute myocardial infarction, sleep problems are associated with neuroendocrine hormones and coagulation activity. The pattern of these relationships is not uniform for patients with a high risk of OSA and those with insomnia symptoms, and whether they contribute to adverse cardiovascular outcomes needs to be established.

Trial registration

ClinicalTrials.gov NCT01781247.

The Clinical Impact of Systematic Screening for Obstructive Sleep Apnea in a Type 2 Diabetes Population-Adherence to the Screening-Diagnostic Process and the Acceptance and Adherence to the CPAP Therapy Compared to Regular Sleep Clinic Patients

Obstructive sleep apnea (OSA) is a common disorder in Type 2 diabetes (T2D) patients further increasing their already high cardiovascular risk. As T2D patients typically not report OSA symptoms, systematic screening for OSA in this population is warranted. We aimed to determine the readiness of T2D patients to undergo screening and to compare their adherence to continuous positive airway pressure (CPAP) therapy with "regular" sleep clinic patients who typically seek medical advice on their own initiative. We therefore recruited 494 consecutive T2D patients and offered them OSA screening using home sleep monitoring (type IV device). All participants in high risk of moderate-to-severe OSA were recommended home sleep apnea testing (HSAT) followed by CPAP therapy. Patients were followed-up for 12 months and outcomes compared to 228 consecutive sleep clinic patients undergoing HSAT. Among 307 screened T2D patients, 94 (31%) were identified at high risk of moderate-to-severe OSA. Subsequently, 54 patients underwent HSAT, 51 were recommended, and 38 patients initiated CPAP (acceptance 75%). Among 228 sleep clinic patients, 92 (40%) were recommended and 74 patients initiated CPAP (acceptance 80%). After 1 year, 15 (39%) T2D and 29 (39%) sleep clinic patients showed good CPAP adherence (use ≥ 4 h/night ≥ 70% nights). In conclusion, 20 T2D patients needed to be screened in order to obtain one successfully treated patient. OSA screening in T2D patients identified 31% with moderate-to-severe OSA. Once diagnosed, their CPAP acceptance and adherence did not differ from sleep clinic patients. However, the reasons for the high dropout during the screening-diagnostic process impacting the overall success of the screening program need to be identified and addressed.

Interactions between and Shared Molecular Mechanisms of Diabetic Peripheral Neuropathy and Obstructive Sleep Apnea in Type 2 Diabetes Patients

Type 2 diabetes (T2D) accounts for about 90% of all diabetes patients and incurs a heavy global public health burden. Up to 50% of T2D patients will eventually develop neuropathy as T2D progresses. Diabetic peripheral neuropathy (DPN) is a common diabetic complication and one of the main causes of increased morbidity and mortality of T2D patients. Obstructive sleep apnea (OSA) affects over 15% of the general population and is associated with a higher prevalence of T2D. Growing evidence also indicates that OSA is highly prevalent in T2D patients probably due to diabetic peripheral neuropathy. However, the interrelations among diabetic peripheral neuropathy, OSA, and T2D hitherto have not been clearly elucidated. Numerous molecular mechanisms have been documented that underlie diabetic peripheral neuropathy and OSA, including oxidative stress, inflammation, endothelin-1, vascular endothelial growth factor (VEGF), accumulation of advanced glycation end products, protein kinase C (PKC) signaling, poly ADP ribose polymerase (PARP), nitrosative stress, plasminogen activator inhibitor-1, and vitamin D deficiency. In this review, we seek to illuminate the relationships among T2D, diabetic peripheral neuropathy, and OSA and how they interact with one another. In addition, we summarize and explain the shared molecular mechanisms involved in diabetic peripheral neuropathy and OSA for further mechanistic investigations and novel therapeutic strategies for attenuating and preventing the development and progression of diabetic peripheral neuropathy and OSA in T2D.

A retrospective analysis on patients at high-risk for obstructive sleep apnea undergoing ear, nose, and throat surgeries

Background

Obstructive sleep apnea (OSA) may be related to episodes of oxygen de‐saturation, hypercapnia, cardiovascular dysfunction, cor‐pulmonale, and pulmonary hypertension. STOP‐BANG is an acronym for eight specific questions used to assess the likelihood of OSA. If the individual exhibits three or more of these indicators, he/she should be considered to be at high risk for OSA complications. Therefore, the decision of proceeding with inpatient versus outpatient ENT surgery still remains controversial. The primary objective of the study was to identify and correlate desaturation (SPO2 <90%) episodes and risk factors.

Methods

We conducted a single‐center retrospective study between October 1, 2011 and August 31, 2014 in order to identify postoperative complications during the first 24 hours that justify postoperative monitoring and hospital admission. A total of 292 subjects were included for data analysis. Patients were divided into two groups based on the number of OSA risk factors: group A with 3–4 risk factors (n = 166), and group B with ≥5 risk factors (n = 126). The following information was collected: demographics, ASA, preoperative STOP‐BANG score, length of surgery, intraoperative complications, opioid consumption, post anesthesia care unit (PACU) and overall length of stay, supplemental oxygen requirement, oxygen desaturation, and postoperative opioid consumption.

Results

No statistically significant difference was found when comparing demographic variables between both groups. All STOP‐BANG variables showed statistical significance. PACU and inpatient variables were similar among both groups, with the exception of length of hospital stay (longer stay in group B when compared to group A [p = 0.003]). Desaturation differences between both groups during PACU were statistically significant (p = 0.008). A post‐hoc analysis showed a 0% incidence of overall desaturation in the group with three STOP‐BANG indicators.

Conclusions

Our retrospective analysis concluded that patients diagnosed with three STOP‐BANG risk factors did not experience postoperative complications and hospital admission was not justified.

Level of Evidence

4

Screening for obstructive sleep apnea syndrome in asthma patients: a prospective study based on Berlin and STOP-Bang questionnaires

BACKGROUND

The bidirectional relationship of asthma and obstructive sleep apnea (OSA) has been confirmed in recent years. However, in the clinical practice, majority of asthma patients did not pay adequate attention to their sleep apnea condition. Berlin questionnaire (BQ) and STOP-Bang questionnaire (SBQ) are two most common OSA screening questionnaires to screen high-risk patients for OSA. This study aimed at evaluating the predictive performance of BQ and SBQ for OSA in asthma patients.

METHODS

Asthma outpatients of Zhongshan Hospital were enrolled into the study. All patients were asked to fill in the BQ and SBQ and clinical characteristics and asthma characteristics were recorded. Univariate and multivariate logistic regression analyses were applied to identify risk factors of OSA in asthma patients. With the gold standard of laboratory-based overnight polysomnography (PSG), the predictive performance of SBQ and BQ was evaluated and compared. The probability of OSA severity was predicted by various SBQ scores in asthma patients.

RESULTS

A total of 123 asthma patients (average age 47.56±12.12 years; 57.72% males) were enrolled and underwent PSG diagnosis overnight at Sleep Center. Logistic regression analyses showed that rhinitis (adjusted OR =4.30; 95% CI: 1.50-12.37, P=0.007) and dyslipidemia (adjusted OR =2.75; 95% CI: 1.16-6.51, P=0.021) were associated with OSA in asthma patients after adjusting for known OSA risk factors. No asthma functional characteristic differences were found to be associated with OSA severity in the study. The prevalence of moderate-to-severe OSA (AHI ≥15) in the asthmatic population sample was 36.59% (45/123). Questionnaires predictive results showed that compared with BQ, SBQ has higher diagnostic sensitivity (84.4% vs. 60%), lower specificity (79.5% vs. 91%) lower positive predictive value (PPV): (70.4% vs. 79.4%) and higher negative predictive value (NPV) (90% vs. 80%) to detect moderate-to-severe OSA at the cut-off as AHI of 15/h. OSA probability results showed that with the increasing of the questionnaire scores, the moderate and severe OSA probability of SBQ rose significantly.

CONCLUSIONS

SBQ is a preferable sleep questionnaire better than BQ for detecting moderate and severe OSA in asthma patients which should be validated in larger population sample.

Obstructive Sleep Apnea and Diabetes: A State of the Art Review

OSA is a chronic treatable sleep disorder and a frequent comorbidity in patients with type 2 diabetes. Cardinal features of OSA, including intermittent hypoxemia and sleep fragmentation, have been linked to abnormal glucose metabolism in laboratory-based experiments. OSA has also been linked to the development of incident type 2 diabetes. The relationship between OSA and type 2 diabetes may be bidirectional in nature given that diabetic neuropathy can affect central control of respiration and upper airway neural reflexes, promoting sleep-disordered breathing. Despite the strong association between OSA and type 2 diabetes, the effect of treatment with CPAP on markers of glucose metabolism has been conflicting. Variability with CPAP adherence may be one of the key factors behind these conflicting results. Finally, accumulating data suggest an association between OSA and type 1 diabetes as well as gestational diabetes. This review explores the role of OSA in the pathogenesis of type 2 diabetes, glucose metabolism dysregulation, and the impact of OSA treatment on glucose metabolism. The association between OSA and diabetic complications as well as gestational diabetes is also reviewed.