Influences of nasal continuous positive airway pressure on sleep architecture of obstructive sleep apnea-hypopnea syndrome patients

Objective To investigate the instant influences of nasal continuous positive airway pressure(nCPAP) on sleep architecture of obstructive sleep apnea-hypopnea syndrome(OSAHS) patients. Methods Eighty-seven OSAHS patients were diagnosed by polysomnography (PSG). The CPAP pressure was titrated during the first night. The patients accepted the whole night nCPAP treatment while PSG was monitored. The sleep architectures, apnea-hypopnea index(AHI) and arterial O2 saturation (SaO2) of OSAHS patients were analyzed before and during nCPAP therapy. Results Sleep architecture, AHI and SaO2 were significantly improved during therapy. AHI reduced from (54, 45±28. 85) times/h to (8.11± 13.41) times/h(F = 184. 528, P<0. 001). Minimum SaO2 increased from (64.33±14.73) % to (75.08 ± 15.52)% (F =21. 948, P <0. 001). Average SaO2 increased from (88.19±6.80)% to (91.99±3.87)% (F = 20. 469, P < 0.001). Stage I time vs total sleep time (TST) reduced from (22.63 ± 20.95) % to (18. 56±16.92) %,total REM sleep time vs TST increased from (13.28± 10.25)% to (16.07±9.87)%, but neither differences were significant (F = 1. 984, P = 0. 161 ; F = 3. 347, P = 0.069). Stage Ⅱ time vs TST reduced greatly from (58.84±22.87)% to (48.67±19.57)%(F =9. 947, P =0. 002). Total slow wave sleep times vs TST increased from (6.29±7.16) % to (17.01±9.84) %(F =67. 511, P <0. 001). Conclusions While AHI and SaO2 are significantly improved during therapy, nCPAP can improve the sleep architecture on OSAHS patients significantly. Key words: Positive pressure;  Respiration;  Sleep apnea; Obstructive;  Sleep architecture