Evaluation of treatment response in patients with seasonal allergic rhinitis using domiciliary nasal peak inspiratory flow

BACKGROUND: Measurement of domiciliary nasal peak inspiratory flow rate (PIFR) may have a role in the objective assessment of treatment response in seasonal allergic rhinitis (SAR). OBJECTIVE: We wished to evaluate the relationship between domiciliary measurement of nasal PIFR and a variety of symptoms associated with rhinitis. METHODS: Thirty-eight nonasthmatic patients, mean age (SEM) 30 years (1.4), with symptomatic SAR were evaluated in a placebo-controlled, single-blind, double-dummy, three way parallel group study. Patients received oral cetirizine 10 mg once daily and were randomized to receive, in addition, either: (i) intranasal mometasone furoate 200 microgram (n = 14); (ii) oral montelukast 10 mg (n = 11); or (iii) placebo (n = 13). All treatments were given once daily for 4 weeks and were preceded by a 1 week placebo period. Domiciliary diary cards were used to record morning (am) and evening (pm) domiciliary nasal PIFR and symptom (nasal, eye, throat) scores and impact on daily activity. A total daily symptom score was then calculated from the sum of these separate symptom scores. RESULTS: Baseline values for symptom scores and PIFR after placebo run-in were not significantly different when comparing the three groups. After 4 weeks of active treatment, there were significant (P < 0.05) improvements in nasal symptoms, total daily symptoms and PIFR with all treatments, with there being no significant confounding effect of pollen count, when analysed as a covariate. There were significant (P < 0.01) correlations for nasal symptom scores vs PIFRam (r = - 0.51) and PIFRpm (r = - 0.56), and similarly for daily activity vs PIFRam (r = - 0.42) and PIFRpm (r = - 0.48). CONCLUSIONS: These results suggest that domiciliary measurements of nasal peak flow correlate significantly with symptoms of seasonal allergic rhinitis and may therefore be a potentially useful objective short-term marker of treatment response.