Pathogenetic role of increased nasal resistance in obese patients with obstructive sleep apnea syndrome.
BACKGROUND
The role of increased nasal resistance in obstructive sleep apnea syndrome (OSAS) remains controversial. The aim of this study was to examine the pathogenetic role of nasal obstruction in obese patients with OSAS.


METHODS
Patients with OSAS (n = 125) at a university hospital were divided into three groups according to body mass index (BMI): nonobese (BMI < 25 kg/m(2)), mildly obese (25 kg/m(2) < or = BMI < 30 kg/m(2)), and obese (BMI > or = 30 kg/m(2)). The subjects underwent nasopharyngoscopy, measurement of nasal resistance, and polysomnography.


RESULTS
We studied 42 nonobese, 47 mildly obese, and 36 obese patients with OSAS. Among the obese, but not the nonobese and mildly obese patients, we found significant correlations between the oxygen desaturation index (ODI) and bilateral nasal resistance (BNR; r = 0.412; p = 0.013), between the ODI and unilateral higher nasal resistance (UHNR; r = 0.413; p = 0.012), and between the apnea index and UHNR (r = 0.334; p = 0.046). Multiple regression analysis incorporating all patients showed that BMI (p < 0.001) and BNR (p = 0.033) were independently related to the ODI.


CONCLUSIONS
In obese patients with OSAS, increased nasal resistance could play an important pathogenetic role in hypoxemic apnea.
Tagaya
Mitsuhiko
M
Department of Otorhinolaryngology, Graduate School of Medicine, Nagoya University, Nagoya, Aichi, Japan.
Nakata
Seiichi
S
Yasuma
Fumihiko
F
Noda
Akiko
A
Morinaga
Mami
M
Yagi
Hidehito
H
Sugiura
Makoto
M
Teranishi
Masaaki
M
Nakashima
Tsutomu
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000403:Airway Resistance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015508:Nasal Obstruction / Q000150:complications*; D009765:Obesity / Q000150:complications*; D017286:Polysomnography; D025363:Rhinomanometry; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D011795:Surveys and Questionnaires