Prevalence and classification of rhinitis in preschool children in Portugal: a nationwide study.
BACKGROUND
Information on rhinitis epidemiology in preschool children is scarce.


OBJECTIVE
To estimate, in children with 3-5 years of age, current rhinitis prevalence, to describe rhinitis symptoms and associated sociodemographic characteristics, and to report allergic rhinitis and its impact on asthma (ARIA) classification.


METHODS
Cross-sectional, nationwide, population-based study including children aged 3-5 years. A multistep selection strategy was used to obtain a representative sample. Data were collected at kindergartens and parish centers by face-to-face interview to caregivers, using an adapted ISAAC questionnaire. 'Current rhinitis' (CR) was defined as the presence of ≥1 rhinitis symptom (repeated sneezing and/or itchy nose, blocked nose for >1 h, or runny nose without having a cold/flu) in the last year. Rhinitis lasting ≥4 days/week and ≥4 consecutive weeks was classified as persistent. Moderate-severe disease interfered 'a moderate amount' or 'a lot' in daily activities.


RESULTS
Five thousand and eighteen children were included. CR prevalence was 43.4% [95% CI (42.0-44.8%); n = 2179] and that of physician-diagnosed rhinitis was 11.7% [95% CI (10.8-12.6%); n = 588]. Of children with CR, 67% reported blocked nose, 48% rhinorrhea, and 46% sneezing/itchy nose. Considering ARIA classification, 30% of the population had mild intermittent, 3% mild persistent, 7% moderate-severe intermittent, and 3% moderate-severe persistent rhinitis. Children with CR had more current wheezing, physician-diagnosed asthma, self-reported food allergy, and family history of allergic disease. These characteristics were also associated with persistent and moderate-severe rhinitis.


CONCLUSIONS
This is the first nationwide population-based study reporting rhinitis prevalence and ARIA classification in preschool children. In this age-group, rhinitis is frequent and underdiagnosed. About 25% children with rhinitis presented moderate-severe disease.
Immunoallergy Department, Hospital CUF-Descobertas, Lisbon, Portugal; Sociedade Portuguesa de Alergologia e Imunologia Clínica (SPAIC), Lisbon, Portugal.
M
M
Morais-Almeida
N
N
Santos
A M
AM
Pereira
M
M
Branco-Ferreira
C
C
Nunes
J
J
Bousquet
J A
JA
Fonseca
D002675:Child, Preschool; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D011159:Population Surveillance; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D012220:Rhinitis / Q000175:diagnosis* / Q000453:epidemiology*; D012307:Risk Factors; D012720:Severity of Illness Index
classification; epidemiology; preschool children; rhinitis; severity