STOP-Bang questionnaire: the validation of a Portuguese version as a screening tool for obstructive sleep apnea (OSA) in primary care.

Introduction: The growing number of suspected patients diagnosed with obstructive sleep apnea (OSA) that are observed in sleep units has increased in the last decade. Therefore, screening methods have become important, especially in primary care (PC).

Aim: This work aimed to test the performance of the STOP-Bang questionnaire for the suspicion/diagnosis of obstructive sleep apnea.

Methods: Eight-month prospective study; all patients referred from PC to the respective sleep clinic accompanied by a completed and translated version of the STOP-Bang questionnaire for a clinical evaluation.

Results: Two hundred fifty-nine observed patients were the study object. The age was 55.14 ± 12.07 years, 71.03% were male patients with a neck circumference of 40.97 ± 3.07 cm and BMI of 31.1 ± 5.14 kg/m. The diagnosis was confirmed in 82.6% of the patients: 34.6% having moderate and 36.8% severe disease. A STOP-Bang score of 3 or more resulted in positive predictive value (PPV) of 88.4% and a sensitivity for OSA of 98.6%. Has the questionnaire score raises, OSA's probability also raises in a proportional basis. For a STOP-Bang score of 6, the OSA probability reaches 98% and for a score of 8, it reaches 80% for severe OSA. Lower scores, 3 or 2, had a negative predictive value (NPV) for moderate-to-severe OSA of 86.96 and 87.5%, respectively.

Conclusion: As much as we know, our study is the first that applied the STOP-Bang questionnaire in Portuguese PC. We demonstrate that these is a useful tool for the stratification of patients with suspicion and diagnosis of OSA, showing a high sensitivity and PPV. Besides that, the probability of severe OSA steadily increases along with its score and we show an excellent NPV with lower scores.