Allergic rhinitis duration and small-airway dysfunction in adolescents without asthma: a cross-sectional impulse oscillometry study

We used impulse oscillometry (IOS) to examine the relationship between AR duration and small-airway function, and examined serum endocan (endothelial cell-specific molecule-1, ESM-1), whose relationship to airway function in AR is unknown, as a candidate systemic biomarker.</p> <p>Forty treatment-naïve, aeroallergen-sensitized adolescents (12–17 years) with AR and 37 non-atopic controls of comparable age and sex underwent IOS, serum endocan measurement (ELISA, enzyme-linked immunosorbent assay), specific immunoglobulin E (IgE) testing, and skin prick testing.

Symptoms were scored on a visual analog scale, and core IOS indices were expressed as age- and sex-adjusted <i>z</i>-scores.</p> <p>No IOS parameter differed between patients and controls. However, longer AR duration was associated with higher total-airway resistance (zR5 <i>r</i> = 0.323, <i>p</i> = 0.042) and lower reactance (zX5 <i>r</i> = −0.502, <i>p</i> < 0.001); specific IgE also increased with age, duration, and severity.