BACKGROUND: Recently, it has been evidenced that the forced expiratory flow at the 25 and 75% of the pulmonary volume (FEF25-75) might be considered as a possible marker of early bronchial impairment in patients with allergic rhinitis alone. Objectives: The aim of this study was to determine whether a spirometric impairment may predict allergy during screening visit. METHODS: The study included 283 Navy soldiers (255 males, mean age 27.1 + 8.2) who had to undergo spirometry for attending specific courses. Fifty-four showed slight spirometric anomalies. Thus, they referred to Navy Hospital of La Spezia for standardized tests: skin prick test, spirometry, and methacholine bronchial challenge. RESULTS: Forty seven (87%) subjects were sensitized (47% monosensitized and 53% polysensitized). Allergic rhinitis was diagnosed in 25 subjects with median nasal TSS 5. FVC and FEV1 values were normal, whereas FEF25-75 values were reduced (61.8 + 14.8 % of predicted), bronchodilation test was significant for FEF25-75 (82.9 + 16.8% of predicted; p<0.001) only. Bronchial hyperreactivity (BHR) was detected in 28 subjects, all but 1 were sensitized. CONCLUSIONS: This study provides evidence, relevant to clinical care, that mild spirometric impairment may generate the suspect of allergic disorders, thus spirometry could be more frequently performed in general population screening.