Abstract
Background:
Obstructive sleep apnea (OSA) remains underdiagnosed in India because polysomnography (PSG) is costly and not widely available. The STOP-Bang questionnaire offers a simple and reliable method to screen high-risk individuals in outpatient settings.
Methods:
A cross-sectional study was conducted among 368 adults attending a tertiary-care hospital in western Gujarat. All participants completed the STOP-Bang questionnaire. A score ≥5 was classified as high-risk for OSA. Data were analyzed using SPSS v24.
Results:
Out of 368 participants, 82 (22.8%) were in the high-risk group (STOP-Bang ≥5), while 277 (77.2%) were low-moderate risk. High-risk scores were significantly more common in males, participants aged >50 years, and those with higher body mass index (BMI).
Conclusion:
About one-fourth of adults screened in this OPD cohort were at high risk for OSA. STOP-Bang proved practical, low-cost, and suitable for early triage in regions where access to PSG is limited.
KEYWORDS: Gujarat, obstructive sleep apnea, polysomnography, screening questionnaire, STOP-bang
INTRODUCTION
Obstructive sleep apnea (OSA) is now recognized as a major sleep-related breathing disorder causing repeated upper-airway obstruction with oxygen desaturation and arousals.[1] Recent global data suggest OSA affects nearly one billion adults and still remains widely underdiagnosed in many regions.[2] It is strongly linked with hypertension, cardiovascular disease and metabolic complications that increases long-term morbidity.[1]
Polysomnography (PSG) is the diagnostic gold standard, but it is costly and less accessible in many Indian hospitals.[3] Because of poor availability of PSG validated screening tools are required for early identification of high-risk individuals.[4]
STOP-Bang questionnaire remains one of the most reliable tools due to high sensitivity and ease of administration in outpatient settings.[5] Recent Indian studies also show STOP-Bang performs well even in non-obese patients who may have craniofacial or anatomical risk factors.[6] Community awareness about OSA in India is still low and many high-risk patients present late with complications.[7] Western India continues to have limited sleep-lab facilities, making OPD-level screening essential.[8]
Therefore, this study was done to estimate the proportion of adults at high risk for OSA using STOP-Bang in a tertiary-care population of Western Gujarat and to identify key associated demographic predictors.
MATERIALS AND METHODS
This cross-sectional observational study was conducted among adults attending the outpatient department of a tertiary care hospital in western Gujarat to identify undiagnosed high-risk individuals for OSA using a standardized screening tool. The study followed the principles of the Declaration of Helsinki. Ethical clearance was obtained from the Institutional Ethics Committee before initiation of the study (IEC/02/2023 PROTOCOL ID NF/45 dated March 17, 2023). Participation was voluntary, and written informed consent was taken from all subjects. No invasive procedure was conducted.
A total of 368 adults aged 18 years and above from different districts of western Gujarat were included. Participants were recruited using a convenience sampling method from the outpatient department during the study period. Patients already diagnosed with OSA or on treatment for sleep disorders were excluded.
All participants completed the STOP-Bang questionnaire, which has eight yes/no questions—four symptom-based (snoring, tiredness, observed apnea, hypertension) and four demographic or anthropometric (BMI >35 kg/m2, age >50 years, neck circumference >40 cm, male gender in Table 1).[3] Each “Yes” scored 1 point, giving a total score of 0–8. Risk was classified as low (0–2), intermediate (3–4), and high (5–8). Those scoring ≥5 were considered high risk and advised overnight PSG [Table 2].[3]
Table 1.
Key participant characteristics
| Variable | Count (n) | % (of 368) | ||
|---|---|---|---|---|
| Male | 161 | 43.8% | ||
| Age >50 years | 247 | 67.1% | ||
| BMI >35 kg/m2 | 2 | 0.5% | ||
| Neck circumference ≥40 cm | 2 | 0.5% | ||
| Snoring (Yes) | 294 | 79.9% | ||
| Tiredness/daytime sleepiness (Yes) | 295 | 80.2% | ||
| Observed apnea (Yes) | 15 | 4.1% | ||
| Known hypertension (Yes) | 142 | 38.6% |
BMI=Body mass index
Table 2.
STOP-Bang risk classification
| STOP-Bang category | Count (n) | % (of 368) | ||
|---|---|---|---|---|
| Low to moderate risk (STOP-Bang score <5) | 286 | 77.7% | ||
| High risk (STOP-Bang score ≥5) | 82 | 22.3% | ||
| Total | 368 | 100% |
Duly filled questionnaires were verified by the investigator and coded before entry in Microsoft Excel. Data were analyzed using IBM SPSS version 24. Descriptive statistics and cross-tabulations were used to assess the relation of demographic variables with OSA risk.
RESULTS
A total of 368 participants were analyzed. Males were 161 (43.8%) and 247 (67.1%) were older than 50 years. Only two participants (0.5%) had BMI >35 kg/m2 and 2 (0.5%) had neck circumference ≥40 cm. Snoring was reported by 294 (79.9%) and daytime tiredness by 295 (80.2%). Observed apnea was uncommon (15, 4.1%) while known hypertension was present in 142 (38.6%).
By STOP-Bang scoring, 286 participants (77.7%) fell into the low-to-moderate risk group (score <5) and 82 (22.3%) were high risk (score ≥5). Overall high-risk burden in this outpatient sample was 22.3%.
DISCUSSION
In this study we found that 22.3% adults in western Gujarat were in high-risk OSA group based on STOP-Bang score ≥5, which is clearly higher than German community data where only 6.7% screened positive.[4] This difference can be because our sample had more older adults, 67.1% above 50 years, and age increases airway collapsibility due to reduced pharyngeal muscle tone and structural narrowing.[1] Male proportion was also high (43.8%) and male upper-airway anatomy with higher soft tissue mass makes them more prone for obstruction during sleep.[9] Snoring and daytime tiredness were reported by almost 80% participants, which itself drives STOP-Bang score upward and may inflate high-risk proportion compared to cohorts with lower symptom burden.[10]
BMI >35 kg/m2 and neck circumference ≥40 cm was rare in our population, yet risk remained high. This supports evidence that STOP-Bang retains performance even in lower BMI Asian phenotypes where craniofacial narrowing plays a greater role than obesity.[11] Indian studies also show higher OSA risk despite modest BMI because of retrognathia and smaller airway size.[12] Our results align with this pattern as age and male gender became key drivers rather than obesity.
ESS alone has limited value in such settings because many Indians under-report sleepiness, considering fatigue as routine lifestyle burden.[13] Hence STOP-Bang is more sensitive due to both symptoms and objective demographic factors, making it a better triage tool for primary-care screening.[14,15] Global reviews also confirm STOP-Bang as practical, fast, and adaptable across clinical and community settings.[7]
The finding of 22.3% high-risk individuals also reflects hospital-based sampling. Such settings tend to include patients with hypertension or metabolic issues who already have higher underlying OSA risk.[14] Hypertension in our cohort was 38.6%, and OSA contributes to sympathetic activation and BP rise, making the association clinically important.[1]
OSA has strong downstream cardiovascular impact including HF, AF, and stroke, hence missed diagnosis increases later disease burden.[15] Western Gujarat still has limited access to overnight PSG, so validated screening questionnaires are needed to detect risk early and prioritize PSG for those with highest score.[10]
Overall, our findings show that STOP-Bang is useful for early risk stratification even in populations with low obesity levels. Male sex, older age, and heavy snoring pattern mainly pushed risk up in our sample. High-risk individuals should be referred for confirmatory PSG, lifestyle counselling, and early cardiovascular assessment, especially in low-resource regions where diagnostic facilities are few.[10]
CONCLUSION
Our study highlights the rising risk of OSA among the population in Gujarat and reinforces the utility of validated screening tools like STOP-Bang and ESS, especially in low-resource settings
Conflicts of interest
There are no conflicts of interest.
Funding Statement
Nil.
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