Objective and subjective assessments of nasal obstruction in children and adolescents with allergic rhinitis

OBJECTIVE: To correlate objective assessment of nasal obstruction, as measured by acoustic rhinometry (volume of the first 5 cm of the nasal cavity) and active anterior rhinomanometry (total nasal airway resistance), with its subjective evaluation (obstruction scores). METHOD: Thirty patients, aged 7 to 18 years, with persistent allergic rhinitis and thirty controls were enrolled. The obstruction score was reported for the whole nasal cavity and for each nostril separately. The three variables were measured at baseline and after induction of nasal obstruction. RESULTS: There were significant and negative correlations between resistance and nasal volume in all groups and scenarios, except for the most obstructed nostril, in the control group, post-obstruction. For the whole nasal cavity, there was no significant correlation between objective and subjective variables except between score and total nasal cavity volume in the control group, post-obstruction. Regarding the most obstructed nostril, we found a significant negative correlation between score and resistance and a significant positive correlation between score and volume for the total group at baseline. There were no clear differences in the correlation coefficients found in patients and controls. The correlation coefficients did not change after induction of nasal obstruction. CONCLUSIONS: Objective assessment of nasal obstruction did not correlate significantly with subjective evaluation for the nasal cavity as a whole, but there was a correlation for unilateral assessments. There was correlation between the objective evaluations. Allergic rhinitis and acute induction of nasal obstruction did not affect the correlation between objective and subjective assessments of nasal obstruction. Addition of an objective method for evaluation of nasal obstruction could be useful in the research setting; if no such method can be used, each nostril should be evaluated separately.