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 (PIF R) may have a role in the objective assessment of treatment response in sea sonal allergic rhinitis (SAR). Objective We wished to evaluate the relationship between domiciliary measur ement 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 cetiri zine 10 mg once daily and were randomized to receive, in addition, either: (i) intranasal mometasone furoate 200 mu g (n = 14); (ii) oral montelukast 10 mg (n = 11); or (iii) placebo (n = 13). All treatments were given once d aily 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 n asal PIFR and symptom (nasal, eye, throat) scores and impact on daily activ ity. 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 we re not significantly different when comparing the three groups. After 4 wee ks of active treatment, there were significant (P < 0.05) improvements in n asal symptoms, total daily symptoms and PIFR with all treatments, with ther e being no significant confounding effect of pollen count, when analysed as a covariate. There were significant (P < 0.01) correlations for nasal symp tom scores vs PIFRam (r = - 0.51) and PIFRpm (r = - 0.56), and similarly fo r daily activity vs PIFRam (r = - 0.42) and PIFRpm (r = - 0.48). Conclusions These results suggest that domiciliary measurements of nasal pe ak flow correlate significantly with symptoms of seasonal allergic rhinitis and may therefore be a potentially useful objective short-term marker of t reatment response.