THE EFFECT OF AGE, SEX, OBESITY AND POSTURE AN UPPER AIRWAY SIZE

Most patients with sleep apnoea/hypopnoea syndrome (SAHS) are middle-a ged men. As there are conflicting data on the effects of age and gende r on upper airway calibre, we tested the hypothesis that increasing ag e and the male sex predispose to upper airway narrowing in normal subj ects. We measured upper airway calibre using acoustic reflection in 60 men and 54 women (median 35, range 16-74 yrs) both seated and supine. All upper airway dimensions, except oropharyngeal junction (OPJ), dec reased with increasing age in both men and women (r>-0.24, p less than or equal to 0.05) while supine (r(2)>0.06). Men had greater changes i n airway area at OPJ on lying down (mean (SEM) 0.5 (0.1), 0.2 (0.1) cm (2); p<0.02). Men had greater body mass indices (mean (SD) 26 (4), 24 (4) kg.m(-2); p=0.04), and larger neck circumferences (mean (SD) 38 (3 ), 33 (2) cm; p<0.0001) than women. For any body mass index, neck circ umference was larger in men than women (p<0.001). This study shows tha t upper airway size decreases with increasing age in both men and wome n, and that men have greater upper airway collapsibility on lying down at oropharyngeal junction than women.