Date Published: January 17, 2019
Publisher: Public Library of Science
Author(s): Michelle J. Suh, Jin A. Park, Suk Won Chang, Jeong Hong Kim, Keun-Hwa Lee, Seong-Chul Hong, Hye-Sook Lee, Ju Wan Kang, Lucia Billeci.
It is difficult to accurately predict the natural course of allergic rhinitis (AR), because it is affected by a wide variety of environmental influences, as well as genetic predisposition. Considering the high prevalence of allergic rhinitis in children and adolescents, caregivers should be given appropriate information regarding the disease course. This study aimed to understand the prognosis of allergic rhinitis by examining the relationship between allergic sensitization and rhinitis symptoms during this developmental period.
This cross-sectional study included 1069 children aged 9–16 years from the Korean International Study of Asthma and Allergies in Childhood Survey database who had completed health questionnaires, and for whom skin prick test results were available. Data were collected during May 2016. The distribution of sensitization and allergic symptoms was compared by age groups (elementary, middle, and high school). Data were analyzed using linear-by-linear analysis.
Sensitization to at least one tested allergen differed by age (59.2%, 58.3%, 68.2%, in elementary, middle, and high school students, respectively; p = 0.025), and seasonal allergen sensitization (35.0%, 37.1%, 53.9%, respectively) increased with age (p < 0.001). Conversely, the proportion of rhinitis symptoms among sensitized children decreased as age increased (58.80%, 52.90%, 49.70%, respectively; p = 0.047). However, the rate of non-allergic rhinitis was age-independent. With increasing age during childhood and adolescence, symptomatic allergic rhinitis decreases; thus, subclinical allergic rhinitis increases. This suggests that the symptoms of later-sensitized children are less clearly manifested, or that the symptoms reduce as previously sensitized children mature. This should be clarified further in a longitudinal study.
The worldwide prevalence of allergic rhinitis (AR) differs widely across countries and regions because the causative allergens and aggravating factors depend on the living environment. The prevalence of AR shows an increasing trend worldwide, especially among school-aged children [1,2]. Active allergic disease reduces children’s quality of life [3,4], and imposes a considerable socioeconomic burden [4,5]. Therefore, it is of interest to determine whether AR in a specific child will deteriorate or develop into asthma or other allergic diseases; moreover, caregivers require counseling regarding how their children’s diseases are likely to change over time. It is presumed that the prevalence of AR increases from childhood to young adulthood, and decreases thereafter [6,7]. Nevertheless, there has not been sufficient research regarding the characteristics of AR in school-aged children.
This study investigated the relationship between allergen sensitization and symptomatic rhinitis in children of different age groups to gain an understanding of the course of AR. Surprisingly, although the rate of allergen sensitization increased with age, the extent of rhinitis symptoms in sensitized children decreased with age; in contrast, non-allergic rhinitis symptoms revealed a growth-independent pattern.
The presence of rhinological manifestations declines with age in children sensitized to allergens. Longitudinal studies are warranted to clarify the clinical significance of asymptomatic sensitization.