The relationship between FEF25-75 and skin test sensitization nasal inflammation, and bronchial hyperreactivity in young subject without asthma.

Background: A close link exists between allergic rhinitis and asthma. Small airway disease (SAD), defined by a reduction in FEF25-75 and normal spirometry (normal FEV1, FVC, and FEV1/FVC ratio), may be a marker for early allergic or inflammatory involvement of the small airways in subjects with allergic diseases and no asthma. Objectives: The aim of the present study was to determine if there is a relationship with SAD, the outcome variable, and several allergic predictors in patients without asthma but with allergic disease. Study Design: Cross-sectional. Methods: Two-hundred eleven midshipmen attending the third and fifth course of Navy Academy of Livorno were screened. Fifty-eight showed slight spirometric anomalies. Thus, they were referred to Navy Hospital of La Spezia for standardized tests: skin prick test, nasal cytology, spirometry, and methacholine bronchial challenge. A reduced FEF25-75 was defined as less than 80% of predicted. Results: All 58 subjects had a normal FEV1, FVC, and FEV1/FVC ratio. Twenty subjects had a reduced FEF25-75 consistent with the definition of SAD. A mean value of FEF25-75 of 70.3 (SD 8.5) was measured in patients with a reduced FEF, while it was 108.0 (SD 14.3) in those with preserved FEF25-75. All the candidate allergic predictors appeared to be strongly associated with a reduced FEF25-75. The proportion of subjects with reduced FEF25-75 appeared to increase with increasing severity of the allergic predictors, and correspondingly the mean value of FEF25-75 appeared to decrease. Conclusions: The FEF25-75 value may be envisioned as a possible marker of SAD in atopic subjects. Moreover, this study supports the link between upper and lower airways in sensitized subjects.