The incremental role of obstructive sleep apnoea on markers of atherosclerosis in patients with metabolic syndrome.
OBJECTIVE
Metabolic syndrome (MS) is associated with subclinical atherosclerosis, but the relative role of obstructive sleep apnoea (OSA) is largely unknown. The main objective of this study is to determine the impact of OSA on markers of atherosclerosis in patients with MS.


METHODS
Eighty-one consecutive patients with MS according to the Adult Treatment Panel III underwent a clinical evaluation, polysomnography, laboratory and vascular measurements of carotid intima media thickness (IMT), carotid-femoral pulse wave velocity (PWV) and carotid diameter (CD) in a blind fashion. OSA was defined as an apnoea-hypopnoea index (AHI) > or =15 events/hour. Multiple linear regression was performed to determine the variables that were independently associated with the vascular parameters.


RESULTS
Fifty-one patients (63%) had OSA. No significant differences existed in age, sex, MS criteria, and cholesterol levels between patients with (MS+OSA) and without OSA (MS-OSA). Compared with MS-OSA patients, MS+OSA patients had higher levels of IMT (661+/-117 vs. 767+/-140 microm), PWV (9.6+/-1.0 vs. 10.6+/-1.6m/s), and CD (6705+/-744 vs. 7811+/-862 microm) (P<0.001 for each comparison). Among patients with MS+OSA, all vascular parameters were similar in patients with and without daytime sleepiness. The independent parameters associated with IMT, PWV, and CD were AHI, abdominal circumference, and systolic blood pressure (R(2)=0.42); AHI and systolic blood pressure (R(2)=0.38); and AHI, age, abdominal circumference and systolic blood pressure (R(2)=0.45), respectively. The R(2) of AHI for IMT, PWV and CD was 0.12, 0.10 and 0.20, respectively.


CONCLUSIONS
OSA is very common and has an incremental role in atherosclerotic burden in consecutive patients with MS.
Drager
Luciano F
LF
Hypertension Unit, Heart Institute (InCor), University of São Paulo Medical School, Av Dr Enéas Carvalho de Aguiar, 44, CEP 05403-904, São Paulo, Brazil. luciano.drager@incor.usp.br
Bortolotto
Luiz A
LA
Maki-Nunes
Cristiane
C
Trombetta
Ivani C
IC
Alves
Maria Janieire N N
MJ
Fraga
Raffael F
RF
Negrão
Carlos E
CE
Krieger
Eduardo M
EM
Lorenzi-Filho
Geraldo
G
D000328:Adult; D050197:Atherosclerosis / Q000150:complications* / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001794:Blood Pressure; D002339:Carotid Arteries / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000378:metabolism*; D008875:Middle Aged; D017286:Polysomnography / Q000379:methods; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000378:metabolism; D017539:Tunica Intima / Q000473:pathology; D017540:Tunica Media / Q000473:pathology; D014851:Wakefulness
D015415:Biomarkers