The Stop-Bang Questionnaire as a Screening Tool for Obstructive Sleep Apnea-Induced Hypertension in Asian Population

Obstructive Sleep Apnea and Hypertension: Updates to a Critical Relationship

Purpose of Review

Obstructive sleep apnea (OSA) is an underdiagnosed illness linked to essential hypertension (HTN), resistant hypertension (r-HTN), and cardiovascular disease (CVD). This review provides updates on the epidemiology, pathophysiology, and treatments of OSA-associated HTN.

Recent Findings

Mild sleep apnea increases the risk for HTN. Eighty-nine percent of young patients aged 18–35 with HTN not attributed to secondary causes have underlying OSA. Home sleep studies are noninferior to formal polysomnography for OSA diagnosis. Nocturnal oxygen desaturation rate is positively correlated with HTN severity. Gut microbiome neo-colonization in response to high-fat diet cravings in patients with OSA alters immune function and worsens HTN. Carbonic anhydrase inhibitors and probiotics show newfound potential for OSA-associated HTN treatment. OSA recognition improves hospital outcomes after a STEMI. Hypoxia-inducible factor (HIF) transcription increases in a dose-dependent manner to hypoxia, and HIFs are strongly linked to cancer growth.

Summary

OSA and HTN are comorbid conditions with adversely connected pathophysiology including sympathetic hyperactivity, gut dysbiosis, proinflammation, endothelial damage, rostral fluid shifts, pharyngeal collapse, intravascular fluid retention, nocturnal energy expenditure, and metabolic derangements. The dose–response effect of OSA on HTN severity challenges blood pressure (BP) control, so those with refractory HTN should be screened for OSA.

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.

Cutoff points in STOP-Bang questionnaire for obstructive sleep apnea

BACKGROUND

Obstructive Sleep Apnea Syndrome (OSAS) is a public health problem of high prevalence and impacts on quality of life, anesthetic complications and cardiovascular diseases. In view of the difficulty in accessing the polysomnography, it is necessary to validate other methods for OSAS diagnostic screening in clinical practice in our country, such as the STOP-Bang questionnaire.

OBJECTIVE

To validate the STOP-Bang questionnaire in Brazilians and evaluate optimal cutoff points.

METHODS

After translation and back-translation, STOP-Bang questionnaire was applied to 71 individuals previously submitted to polysomnography and classified into control, mild, moderate or severe OSAS.

RESULTS

The majority of patients was male (59.2%), white (79%), aged 48.9±13.9 years, and with neck circumference >40 centimeters (73.8%). STOP-Bang score was higher in OSAS mild (median/inter-quartis 25-75%: 5/3.5-6), moderate (4.5/4-5) and severe (5/4-6), versus control (2.5/1-4). The receiver operating characteristic (ROC) curve indicate that scores 3, 4 and 6, present the best specificity values (100, 80 and 92.9%) with acceptable sensitivity (60, 66.7 and 50%) in the mild, moderate and severe OSAS subgroups, respectively. In OSAS group analysis (Apnea Hypopnea Index [AHI] ≥5, <15, ≥15 - <30, ≥30), STOP-Bang cutoff point of 6 was optimal to detect OSAS.

CONCLUSION

STOP-Bang Brazilian version identified OSAS patients with lower sensitivity and higher specificity compared to previous studies. Different cutoff points would improve the performance to detect patients with more severe OSAS.

[A modified STOP-Bang questionnaire for OSA screening in the young, middle-age women]

Objective:The STOP-Bang（S-B） questionnaire is widely used for screening patients with OSA. However, BMI and NC cutoff value in the original S-B questionnaire is 35 kg/m²and 40cm, the BMI and NC value in the young and middle-aged female patients in China is lower than that. We aimed to establish a more appropriate modified STOP-Bang（MS-B） questionnaire. Method:A total of 523 cases with suspected OSA in the young and middle-aged female were included in this study. All patients were asked to completed the S-B, MS-B questionnaire and undergo overnight polysomnography（PSG）. The BMI and NC value of the MS-B were determined by the optimal operating points of the ROC. The ability of S-B and MS-B were assessed by ROC and McNemar's test. Result:BMI=28 kg/m²and NC=36 cm as alternative cutoff is to refine S-B questionnaire. When taking apnea hypopnea index（AHI） ≥5 times/h, ≥15 times/h and ≥30 times/h as cut-offs, MS-B had higher sensitivity（88.7% vs 86.7%, 92.8% vs 87.7%, 95.0% vs 90.1%, respectively） and the area under the curve（0.74 vs 0.706, 0.734 vs 0.703, 0.739 vs 0.699, respectively） than S-B. There were significant differences in McNemar test（P<0.05）. Conclusion:This study examined the clinical utility of MS-B. MS-B may improve predictive performance of S-B questionnaire in the young and middle-aged female with OSA.

Rethinking neck circumference in STOP-BANG for Asian OSA

Introduction:

The STOP-BANG questionnaire is a simple screening tool for obstructive sleep apnoea (OSA) which has been validated for use in Asian populations. The original cut-off values for neck circumference were defined based on Caucasian populations. This study aims to validate the neck circumference component of the STOP-BANG score in Asians.

Methods:

A retrospective analysis of all patients suspected of having OSA who underwent a diagnostic polysomnography at a tertiary sleep centre in Singapore over the course of 1 year was conducted. Neck circumference was measured and correlated to the presence of OSA. A receiver operating curve was performed to obtain the optimal cut-off value for screening OSA in Asian patients.

Results:

591 Asian subjects with OSA were analysed. The optimal neck circumference predictive for OSA was found to be 39 cm in males and 35 cm in females, with a sensitivity of 83.4% and 84.6% respectively. The existing STOP-BANG cut-off of 40 cm had 71% and 32% sensitivity in Asian males and females, respectively.

Conclusion:

The STOP-BANG cut-off value for neck circumference for screening for sleep apnoea in Asian males can be maintained at 40 cm, but the neck circumference value used for screening Asian females should be lowered to 35 cm.

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