PURPOSE: Awareness regarding obstructive sleep apnea (OSA) among general public as well as practicing physicians is low in India. The present study was undertaken to test the utility of modified Berlin questionnaire for risk categorization of obstructive sleep apnea in Indian setting.
METHODS: The modified Berlin questionnaire was administered in 180 middle aged adults (of 320 screened), of whom, 104 underwent overnight polysomnograhy, in a cross-sectional study at a tertiary care, national referral center, All India Institute of Medical Sciences (AIIMS), in north India. Questionnaire addressed the presence of frequency of snoring, wake time sleepiness, fatigue, obesity and hypertension. Subjects with persistent and frequent symptoms in any two of these three domains were considered in high-risk category for obstructive sleep apnea. Overnight polysomnograhy was performed to measure apnea and hypopnea index (AHI).
RESULTS: Questions about the symptoms demonstrated internal consistency (Cronbach α correlations 0.92-0.96). Of the 180 respondents to the screening questions, 80 were in high-risk and the rest were in low-risk group. For 104 subjects, who underwent polysomnograhy, risk grouping was useful in prediction of AHI. High-risk category predicted an AHI ≥ 5 with a sensitivity of 86%, specificity of 95%, PPV of 96% and NPV of 82%. These results are comparable to Berlin questionnaire study done in the western population for validation.
CONCLUSION: On the basis of the findings of present study it is concluded that administration of modified Berlin questionnaire prior to a Polysomnography study can identify high-risk subjects and can thus avoid unnecessary Polysomnography studies especially in resource-limited settings.
CLINICAL IMPLICATIONS: To identify subjects at risk for OSA syndrome in general population, this questionnaire can be applied. The findings of present study may be confirmed further by administering modified Berlin questionnaire in a large number of subjects in a community-based setting.
DISCLOSURE: Sanjeev Sinha, None.