RELATIONSHIP BETWEEN BODY-MASS INDEX, AGE AND UPPER AIRWAY MEASUREMENTS IN SNORERS AND SLEEP-APNEA PATIENTS

Anatomical pharyngeal and craniofacial abnormalities have been reporte d using upper airway imaging in snorers with or without obstructive sl eep apnoea (OSA), However, the influences of the age and weight of the patient on these abnormalities remain to be established, The aim of t his study was, therefore, to evaluate in a large population of snorers with or without OSA, the relationship between body mass index (BMI), age and upper airway morphology. One hundred and forty patients were r eferred for assessment of a possible sleep-related breathing disorder and had complete polysomnography, cephalometry and upper airway comput ed tomography. For the whole population, OSA patients had more upper a irway abnormalities than snorers, When subdivided for BMI and age, how ever, only lean or younger OSA patients were significantly different f rom snorers as regards their upper airway anatomy, The shape of the or opharynx and hypopharynx changed significantly with BMI both in OSA pa tients and snorers, being more spherical in the highest BMI group due mainly to a decrease in the transverse axis, On the other hand, older patients (>63 yrs), whether snorers or apnoeics, had larger upper airw ays at all pharyngeal levels than the youngest group of patients (<52 yrs), For the total group of patients, upper airway variables explaine d 26 % of the variance in apnoea/hypopnoea index (AHI), whereas in lea n (BMI <27 kg . m(-2)) or youngest (age <52 yrs) subjects upper airway variables explained, respectively 69 and 55 % of the variance in AHI. In conclusion, in lean or young subjects, upper airway abnormalities explain a major part of the variance in apnoea/hypopnoea index and are likely to play an important physiopathogenic role, This study also su ggests that the shape of the pharyngeal lumen in awake subjects is mor e dependent on body mass index than on the presence of obstructive sle ep apnoea, Further investigation way imaging for surgical selection in obstructive sleep apnoea and young patients.