Relationship between body mass index and CT measure of pharynx about patients with obstructive sleep apnea hyponea syndrome in sleeping

Abstract

Objective To investigate relationship between body mass index (BMI) and CT measurement of pharynx about obstructive sleep apnea hypopnea syndrome(OSAHS) patients in sleeping. Methods Among the patients diagnosed as OSAHS with PSG testing in the hospital,40 cases, who were compatible with the sleep state of spiral CT scanning, were randomly selected,and they were divided into two groups by body mass index(BMI):BMI<25 group and BMI≥25 group. Comparison between two groups were made concerning general condition [average age, neck circumference, minimal oxygen saturation, (apnea hypopnea index, AHI), smoking, wake oxygen saturation] and shapes of pharyngnx (minimum areas of nasopharynx and oropharynx,length,thiekness and area of tongue, length, thickness and cross-sectional area of soft palate,uvula diameter, ete). Results In sleeping,data comparative results of different BMI were as follows:neck circumferenee,AHI in BMI≥25 group were higher than those in BMI<25 group(P<0.01), minimal oxygen saturation in BMI≥25 group was lower than that in BMI<25 group(P<0.001). At the same time, the former had larger length and area of tongue(P<0.001), and smaller minimum area of retropalatal region (P<0.05). With increase of BMI, the minimun area of retroglossal region, length, thickness and area of soft palate tongue thickness increased. But there were no statistical significance. At the same time,correlation analysis showed significant positive correlation between AHI and BMI (r=0.608, P<0.001). Conclusions There is obviously difference between different BMI of OSAHS patients in sleeping, and AHI is associated with BMI. BMI can reflect the degree of upper airway obstruction in OSAHS patients. Key words: Obstructive sleep apnea hypopnea syndrome; Sleeping; Body mass index; CT measure of pharynx; Apnea hypopnea index