PREDICTIVE VALUE OF CLINICAL-FEATURES FOR THE OBSTRUCTIVE SLEEP-APNEASYNDROME

The advantage of being a National Referral Centre for patients with su spected obstructive sleep apnoea (OSA) was used to seek clinical facto rs predictive of OSA, and thus determine if the number of polysomnogra phy tests required could be reduced, Patients were mainly primary refe rrals, from an island population of 3.5 million, Two hundred and fifty consecutive patients underwent clinical assessment, full polysomnogra phy, and a detailed self-administered questionnaire, This represents o ne of the largest European studies, so far, utilizing full polysomnogr aphy, Fifty four percent (n=134) had polysomnographic evidence of OSA (apnoea/hypopnoea index (AHI) greater than or equal to 15 events . h(- 1) sleep), Patients with OSA were more likely to be male, and had a si gnificantly greater prevalence of habitual snoring, sleeping supine, w akening with heartburn, and dozing whilst driving, Alcohol intake, age and body mass index (BMI) were significant independent correlates of AHI, After controlling for BMI and age, waist circumference correlated more closely with AHI than neck circumference among males, while the opposite was true among females. No single factor was usefully predict ive of obstructive sleep apnoea, However, combining clinical features and oximetry data, where appropriate, approximately one third of patie nts could be confidently designated as having obstructive sleep apnoea or not, The remaining two thirds of patients would still require more detailed sleep studies, such as full polysomnography, to reach a conf ident diagnosis.