[Value of oxygen saturation combined airflow in diagnosis of obstructive sleep apnea hypopnea syndrome].

OBJECTIVE: To assess the diagnostic value of oxygen saturation combined with airflow (OF) monitoring for diagnosis of obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: Sixty-two subjects including suspected OSAHS and non-snorers underwent overnight polysomnography (PSG) and OF monitoring simultaneously in sleep laboratory. The apnea-hypopnea index (AHI), lowest oxygen saturation (LSaO(2)), and oxygen desaturation index (ODI) recorded by OF were compared with those recorded by PSG. The AHI and ODI data that showed skew distribution underwent square root transformation to approximate to normal distribution. Pair t test was used for difference hypothesis test. The agreement between the two measures was analyzed using Bland-Altman plot. RESULTS: Forty-five of the 62 subjects were diagnosed as with OSAHS based on PSG with the mean AHI value of (40 +/- 27) events per hour. The mean AHI values derived from OF (OF-AHI) and PSG (PSG-AHI) according to total sleep time were (28 +/- 26) and (29 +/- 28) times per hour respectively, and those after square root transformation were (4.6 +/- 2.7) and (4.7 +/- 2.7) times per hour respectively (P = 0.08). The mean LSaO(2) derived from OF (OF-LSaO(2)) was (82 +/- 11)%, not significantly different from that derived from PSG (PSG-LSaO(2)) [(82 +/- 10)%, P = 0.65]. The ODI derived from OF (OF-ODI) after square root transformation was (3.0 +/- 2.4) times/h, significantly lower than that derived from PSG (PSG-ODI) after square root transformation [(4.0 +/- 2.9) times/h, P = 0.00]. The Bland-Altman plot revealed a good agreement between the OF-AHI and PSG-AHI in non-OSAHS people and patients with mild OSAHS (P = 0.28), however, the OF-AHI was lower than PSG-AHI (P = 0.00) in the patients with moderate to severe OSAHS. There was no significant difference between OF-LSaO(2) and PSG-LSaO2 (P = 0.65). CONCLUSIONS: There is a good agreement between OF and PSG for AHI and LSaO(2). OF can be used to screen patients with suspected OSAHS in high risk population. However, OF tends to underestimate the AHI in moderate to severe OSAHS so additional manual analysis is necessary to confirm the diagnosis.

[The prevalence of snoring in male pilots].

OBJECTIVE: To investigate and analysis the prevalence and risk factors of snoring and excessive daytime sleepiness among male pilots. METHODS: 1108 subjects were derived from a random sample of pilots. They were asked to answer the questions from a questionnaire concerning their snoring and daytime sleepiness, etc. 1054 questionnaire were available for evaluation. RESULTS: The overall prevalence of snoring among male pilots was 51.04% (538/1054), while moderate and severe snorers accounted for 26.28% (227/1054). The prevalence of snoring among male pilots aged over 30 yr was 63.68% (426/669). The prevalence and severity of snoring increase with age and BMI. Age, overweight and obesity, alcohol ingestion and family history of snoring were associated with the prevalence and severity of snoring. There was significant difference in Epworth sleepiness scale scores among without snoring group and various severity of snoring groups (chi2 = 16.948, P < 0.05). CONCLUSION: The prevalence of snoring is high in male pilots. The Epworth sleepiness scale score increase with increasing degree of snoring. Doctors should pay more attention to snoring in male pilot.