Relationship between anoxia accumulation time and related factors in patients with sleep apnea hypopnea syndrome

Objective To explore the relationships between anoxia accumulation time and daytime sleepiness and body mass index in patients with sleep apnea-hypopnea syndrome(SAHS). MethodsAltogether 1 093 patients with suspected SAHS were detected with polysomnography(PSG). Excessive Daytime Sleepiness was assessed with Epworth sleepiness scale (ESS). Apnea-hypopnea index (AHI) ,mean oxygen saturation level during sleep time(MeanSaO2),the lowest oxygen saturation level(LSaO2),the percent of the total recorded time spent below 0.90 oxygen saturation level (TS90 %,TS80%,TS70%),ESS and body mass index (BMI) was calculated. Pearson linear correlation was used to study the association between TS90%,TS80%,TS70% and ESS,BMI. ResultsThere was a positive correlation between ESS and TS90%,TS80%,TS70%(r= 0.324,0.259,0.186; P0.01) respectively; There was a positive correlation between BMI and TS90%,TS80%,TS70%(r=0.521,0.432,0.364; P0.01). LSaO2 had a negative relationship with ESS(r=-0.220,P0.01) or BMI(r=-0.399,P0.01). ConclusionsThe anoxia accumulation time is closely correlated with daytime sleepiness and BMI in SAHS patients. The longer the oxygen desaturation accumulation time,the higher the BMI and the more severe the daytime sleepiness will be.