Association of High-Sensitivity C-Reactive Protein Levels with Proximal Airway CT Morphology in Obesity

Obesity and airway collapse are closely associated, yet the underlying mechanisms remain unclear. This study aimed to evaluate airway collapsibility in relation to markers of adiposity and high-sensitivity C-reactive protein (hs-CRP) levels in obese individuals.

We conducted a cross-sectional study comparing changes in the lumen area and circularity of proximal airways using chest CT imaging in four groups: obese individuals (BMI 30-39.9 kg/m²) with low hs-CRP (< 3 mg/L), obese individuals with moderate hs-CRP (3-8 mg/L), morbidly obese individuals (BMI ≥ 40 kg/m²) with moderate hs-CRP, and morbidly obese individuals with high hs-CRP (> 8 mg/L).

Morbidly obese individuals with high hs-CRP exhibited the most pronounced airway collapse, with regional asymmetry in collapsibility. hs-CRP was significantly associated with BMI, android and gynoid fat mass, and subcutaneous adipose tissue area (all P < 0.001). In multivariate analysis, change in airway circularity was associated with BMI and change in airway lumen area was associated with BMI and hs-CRP, but neither was related to adiposity distribution.

The inflammatory aspects of obesity, reflected by hs-CRP, may exacerbate proximal airway collapse and regional ventilation abnormalities beyond the mechanical effects of fat accumulation.