Obstructive sleep apnea and abdominal aortic calcification: Is there an association independent of comorbid risk factors?
BACKGROUND
No studies have addressed the relationship between obstructive sleep apnea (OSA) and abdominal aortic calcification (AAC), a marker for subclinical atherosclerosis and future cardiovascular events.


OBJECTIVE
To investigate 1) the association between OSA severity and AAC, and 2) whether OSA can impact the extent of AAC independent of comorbid atherogenic risk factors.


METHODS
390 participants aged 40-70 years underwent polysomnography and abdominal computed tomography. AAC was separately quantified in the upper and lower abdominal aorta using the modified Agatston scoring method, and the total AAC score was calculated as a sum of the two scores. OSA was defined as none/mild (apnea-hypopnea index [AHI] <15, n = 87), moderate (AHI 15-30, n = 129), and severe (AHI ≥30, n = 174).


RESULTS
Log-transformed total AAC score adjusted for age and body mass index (BMI) was greater in participants with an elevated AHI (3.4 for none/mild OSA, 3.7 for moderate OSA, and 4.2 for severe OSA, p = 0.04). Multivariate linear regression analysis including age and BMI as covariates showed that severe OSA was associated with higher scores for the lower and total AAC (β = 0.15 and 0.14, p = 0.01 and 0.01, respectively). The association did not persist after additionally adjusting for traditional atherogenic risk factors including visceral fat, smoking, hypertension, dyslipidemia, and diabetes.


CONCLUSIONS
Severe OSA was associated with a greater extent of AAC, which was dependent on coexisting atherogenic risk factors. Comorbid cardiometabolic disorders may largely mediate the association of OSA with subclinical atherosclerosis.
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Ryo
R
Tachikawa
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Sho
S
Koyasu
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Takeshi
T
Matsumoto
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Satoshi
S
Hamada
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Masanori
M
Azuma
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Kimihiko
K
Murase
Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Kiminobu
K
Tanizawa
Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Morito
M
Inouchi
Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Toru
T
Oga
Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Michiaki
M
Mishima
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Kaori
K
Togashi
Department of Respiratory Care and Sleep Control Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Electronic address: chink@kuhp.kyoto-u.ac.jp.
Kazuo
K
Chin
D000328:Adult; D000368:Aged; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging; D001018:Aortic Diseases / Q000175:diagnosis / Q000453:epidemiology*; D001027:Aortography / Q000379:methods; D058070:Asymptomatic Diseases; D050197:Atherosclerosis / Q000175:diagnosis / Q000453:epidemiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017286:Polysomnography; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed; D061205:Vascular Calcification / Q000175:diagnosis / Q000453:epidemiology*
Abdominal aorta; Arterial calcification; Atherosclerosis; Cardiovascular risk factors; Obstructive sleep apnea