The relationship between serum fatty-acid binding protein 4 level and lung function in Korean subjects with normal ventilatory function

BACKGROUND The aim of this study was to assess the association of lung function with serum fatty-acid binding protein 4 (FABP4) in apparently healthy Korean adults. METHODS In 495 participants in a health screening program, Force Exploratory Volume (FEV) 1 and Forced Vital Capacity (FVC) were assessed with standard spirometry. Subjects with obstructive (n = 19) and restrictive (n = 45) lung function were excluded from the analysis. Serum FABP4 level was measured by enzyme-linked immunosorbent assay and transformed into Ln(FABP4). 431 subjects with normal ventilator function (72.4% men, mean age 41 years) were included in the final analysis. RESULTS Mean Ln(FABP4) significantly decreased in subjects from 1(st) quartile to 4(th) quartile of FVC (p = 0.008). Ln(FABP4) did not show significant differences across the quartile groups of FEV1. The odds ratio (OR) of being in the lowest quartile of FVC was 2.704 in subject with 3(rd) tertile of Ln(FABP4) after full adjustment for confounding variables {95% confidence interval (CI) 1.397 ~ 5.357}. OR of being in the lowest quartile of FEV1 was 1.822 (95% CI 1.021 ~ 3.298) in subjects with 3(rd) tertile of Ln(FABP4) after adjustment of age and sex, which was attenuated after full adjustment for confounding variables. CONCLUSION Increased FABP4 level showed increased risk for reduced lung function in subjects with normal ventilatory function.