Serum levels of adipocyte fatty acid-binding protein are independently associated with left ventricular mass and myocardial performance index in obstructive sleep apnea syndrome.
OBJECTIVE
To investigate the cross-sectional association between serum adipocyte fatty acid-binding protein (A-FABP) level and diagnosis or severity of obstructive sleep apnea syndrome (OSAS) and some echocardiographic indices related with cardiac dysfunction.


METHODS
In this study, plasma A-FABP and high-sensitivity C-reactive protein concentrations were measured, and echocardiography was performed in subjects without any cardiac or pulmonary disease who were referred for evaluation of OSAS. According to the apnea-hypopnea index (AHI), subjects were classified into 3 groups: control group (AHI <5; n = 33), mild to moderate OSAS (30 > AHI ≥ 5; n = 30), and severe OSAS (AHI ≥ 30; n = 31).


RESULTS
Levels of A-FABP were significantly different between the groups (P < 0.001). After post hoc analyses, all 3 groups were also significantly different from each other. The levels of A-FABP were significantly higher in the patients with severe OSAS (36.4 ± 13.0 ng/mL) than in the control subjects (9.3 ± 4.6 ng/mL; P < 0.0001) or in patients with mild-moderate OSAS (24.5 ± 10.5 ng/mL; P < 0.001). Patients with myocardial performance index (MPI) greater than 0.47 had higher serum A-FABP levels than those with MPI of less than 0.47 (31.8 ± 13.2 ng/mL vs 10.9 ± 6.3 ng/mL; P = 0.001). Multivariable regression analyses revealed that increased serum A-FABP concentrations were independently associated with increased left ventricular mass index (β = 0.195; P = 0.033) and increased MPI (β = 0.165; P = 0.015).


CONCLUSIONS
Increased A-FABP levels were found in the patients with OSAS, which were correlated significantly with left ventricular mass index and MPI. Further prospective studies are needed to clarify whether increased serum A-FABP level is a marker or a potential mechanism for left ventricular involvement in patients with OSAS.
Department of Cardiology, Turkiye Yuksek Ihtisas Education and Research Hospital, Ankara, Turkey.
Mustafa Mücahit
MM
Balci
Uğur
U
Arslan
Hikmet
H
Firat
Ibrahim
I
Kocaoğlu
Mustafa Gökhan
MG
Vural
Kevser Gülcihan
KG
Balci
Orhan
O
Maden
Oğuz Alp
OA
Gürbüz
Sadik
S
Ardiç
Ekrem
E
Yeter
D000328:Adult; D050556:Fatty Acid-Binding Proteins / Q000097:blood*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008297:Male; D009206:Myocardium / Q000473:pathology*; D009929:Organ Size; D012044:Regression Analysis; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography
C493410:FABP4 protein, human; D050556:Fatty Acid-Binding Proteins