Allergic Rhinitis Causes Loss of Smell in Children: The OLFAPEDRIAL Study
PURPOSE OF THE STUDY.
To evaluate the impact of allergic rhinitis on olfaction in children and characterize it using the ARIA (Allergic Rhinitis and Its Impact on Asthma) criteria for severity and duration.
This study included 1260 children who were 6–12 years of age with allergic rhinitis diagnosed by an allergist from 271 centers in Spain between May and July 2008.
This was an observational, cross-sectional, multicenter study. Inclusion criteria included symptoms of rhinoconjunctivitis for >1 year, sensitization to 1 or more aeroallergens by skin or specific immunoglobulin E testing, and discontinuation of maintenance medications for allergic rhinitis at least 2 weeks prior to inclusion. Baseline evaluation for comorbidities (including atopic dermatitis, rhinosinusitis, asthma, otitis media with effusion, and adenoid hypertrophy) was completed. Using the ARIA criteria, subjects were classified as having intermittent (IAR) or persistent (PER) rhinitis with mild, moderate, or severe symptoms. The subjective loss of smell was measured using a 4-point scale (0, no symptoms; 3, severe symptoms). Descriptive and categorical data were analyzed using χ2, Mann-Whitney, and Kruskal-Wallis tests.
The mean age of subjects was 9 years; 41% were female. Many of the participants had atopic comorbidities, including 49.5% with asthma and 40% with atopic dermatitis. In regard to allergen sensitization, 53% of subjects had positive skin prick test results for pollen, 43% for dust mite, 14% for animal dander, and 7% for mold. Five hundred and fifty-five children (44%) reported smell dysfunction (primary outcome). Subjects reported both a loss of smell frequency (52.1%; P <.001) and intensity (0.75±0.84; P <.0001). The prevalence of olfactory dysfunction was higher among subjects with PER (52.1%) compared with patients with IAR (38%). There was a positive correlation between loss of smell and disease severity (IAR [r = 0.26; P <.0001] and PER [r = 0.20; P <.0001]). The study authors also noted that the intensity of smell loss was rated higher among subjects with moderate and severe forms of the disease.
Allergic rhinitis causes mild-to-moderate olfactory dysfunction in children, specifically loss of smell frequency and intensity. This dysfunction was more prevalent in those with more persistent and severe forms of the disease. Thus, the loss of smell can be used as a clinical marker of disease severity.
This large, cross-sectional multicenter study provides clinically useful information regarding the impact of allergic rhinitis on olfaction. However, a limitation of this study was the use of a subjective assessment of smell instead of a validated clinical survey or objective measurements to assess olfaction. The study authors do acknowledge this limitation and cite the scarcity of tests available for evaluating olfactory function in young children. Furthermore, the patients’ age and development may prove difficult when it comes to discerning certain odor stimuli or reading labels. Regardless, this study provides useful guidance for the general pediatrician and subspecialty provider for assessing the impact of allergic rhinitis symptoms on patient well-being.
- Copyright © 2017 by the American Academy of Pediatrics