Prognosis of the middle-aged and aged patients with obstructive sleep apnea syndrome.
The long-term natural course of obstructive sleep apnea syndrome (OSAS) is studied in order to determine whether severity of nocturnal oxygen desaturation associated with apnea/hypopnea, body mass index (BMI), and hypertension influence survival in young (<40 years), middle-aged (40-64 years), and aged (> or = 65 years) using a questionnaire survey. One hundred and forty-eight patients with OSAS aged 17-78 years (136 men, 12 women, mean 52.0+/-12.3 years), who were diagnosed by standard polysomnography (PSG) between 1983 and 1993, participated in the study. The survey revealed 15 deaths and 101 survivors; 32 subjects could not be located. The survival rate was 71.4% (95% confidence interval: 55.6-87.2%). The survival rate in patients with OSAS was significantly lower than that in the age and sex-adjusted control Japanese population (87.6%). In the young group, only one death (a 19-year-old woman) occurred unexpectedly during sleep. The patient showed an apnea/hypopnea index (AHI) of 33 per h and the length of time that the nocturnal oxygen saturation (SaO2) fell below 90% (time of SaO2 <90%) of 205 min. The survival rate in middle-aged patients with OSAS was significantly lower than that in the age and sex-adjusted control Japanese population (79.2 vs 91.0%), but this pattern was not seen among the aged. Time of SaO2 <90% was significantly longer in the middle-aged patients than in the aged patients, but AHI did not differ between the two groups. Moreover, it was significantly correlated with AHI in middle-aged patients, but not in the aged patients. The survival rate was significantly lower in patients with hypertension than in the patients without such complications in the middle-aged group (57.9 vs 90.4%). Cox proportional-hazard regression model including age, hypertension, BMI, AHI, lowest SaO2, and time of SaO2 <90% showed that hypertension was only significantly associated with lower survival rate in total group and middle-aged patients, but not in the young or aged patients. The prognosis in patients with OSAS may differ among the generations. The prognosis in the middle-aged population may depend on the role of OSAS on the complications of hypertension or severity of oxygen desaturation, but not on AHI only.
Noda
A
A
Nagoya University School of Health Sciences, Department of Clinical Laboratory Medicine, Nagoya University Hospital, Japan.
Okada
T
T
Yasuma
F
F
Sobue
T
T
Nakashima
N
N
Yokota
M
M
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology; D007564:Japan; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D017286:Polysomnography; D012737:Sex Factors; D012891:Sleep Apnea Syndromes / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology; D015996:Survival Rate
D010100:Oxygen