Influence of age on clinical characteristics, pharmacological management and exacerbations in children with asthma
File(s)
Accepted version
Author(s)
Khalaf, Zainab
Bush, Andy
Saglani, Sejal
Bloom, Chloe
Type
Journal Article
Abstract
Background Asthma trials and guidelines often do not distinguish between adolescents and younger children. Using a large English data set, we evaluated the impact of age on asthma characteristics, management and exacerbations.
Methods Primary care medical records, 2004–2021, were linked to hospital records. Children were categorised by age at diagnosis and followed until the next age bracket. Ages (based on management guidelines) were 5–8 years, 9–11 years and adolescents (12–16 years). Characteristics evaluated included body mass index, allergies and events before and after diagnosis (symptoms, medication). Exacerbation incidence was calculated. Multivariable Cox proportional hazards determined associations with exacerbations.
Results 119 611 children were eligible: 61 940 (51.8%) 5–8 years, 32 316 (27.7%) 9–11 years and 25 355 (21.2%) adolescents. Several characteristics differed by age; children aged 5–8 years had the highest proportion with eczema, food/drug allergy and cough, but adolescents had the highest proportion with overweight/obesity, aeroallergen sensitisation, dyspnoea and short-acting-beta-agonist only use. Exacerbation rates were highest in the youngest children (per 100 person-years (95% CI): 5–8 years =13.7 (13.4–13.9), 9–11 years =10.0 (9.8–10.4), adolescents =6.7 (6.5–7.0)). Exacerbation risk factors also differed by age; 5–8 years: male, eczema and food/drug allergy were strongly associated, but for children ≥9 years old, obesity and aeroallergen sensitisation were strongly associated. For all children, higher socioeconomic deprivation was significantly associated with having an exacerbation. Delayed diagnosis was most common in children aged 5–8 years and was associated with increased exacerbations across all ages.
Conclusion Children’s baseline characteristics and exacerbation rates varied according to their age group. Clinical guidelines should consider age at time of diagnosis more discretely than the broad range, 5–16 years, as this appears to impact on asthma severity and management.
Methods Primary care medical records, 2004–2021, were linked to hospital records. Children were categorised by age at diagnosis and followed until the next age bracket. Ages (based on management guidelines) were 5–8 years, 9–11 years and adolescents (12–16 years). Characteristics evaluated included body mass index, allergies and events before and after diagnosis (symptoms, medication). Exacerbation incidence was calculated. Multivariable Cox proportional hazards determined associations with exacerbations.
Results 119 611 children were eligible: 61 940 (51.8%) 5–8 years, 32 316 (27.7%) 9–11 years and 25 355 (21.2%) adolescents. Several characteristics differed by age; children aged 5–8 years had the highest proportion with eczema, food/drug allergy and cough, but adolescents had the highest proportion with overweight/obesity, aeroallergen sensitisation, dyspnoea and short-acting-beta-agonist only use. Exacerbation rates were highest in the youngest children (per 100 person-years (95% CI): 5–8 years =13.7 (13.4–13.9), 9–11 years =10.0 (9.8–10.4), adolescents =6.7 (6.5–7.0)). Exacerbation risk factors also differed by age; 5–8 years: male, eczema and food/drug allergy were strongly associated, but for children ≥9 years old, obesity and aeroallergen sensitisation were strongly associated. For all children, higher socioeconomic deprivation was significantly associated with having an exacerbation. Delayed diagnosis was most common in children aged 5–8 years and was associated with increased exacerbations across all ages.
Conclusion Children’s baseline characteristics and exacerbation rates varied according to their age group. Clinical guidelines should consider age at time of diagnosis more discretely than the broad range, 5–16 years, as this appears to impact on asthma severity and management.
Date Issued
2024-01-18
Date Acceptance
2023-10-28
Citation
Thorax, 2024, 79 (2), pp.112-119
ISSN
0040-6376
Publisher
BMJ Publishing Group
Start Page
112
End Page
119
Journal / Book Title
Thorax
Volume
79
Issue
2
Copyright Statement
Copyright © 2023 The Author(s). This article has been accepted for publication in Thorax 2024 following peer review, and the Version of Record can be accessed online at https://doi.org/10.1136/thorax-2023-220603
License URL
Identifier
https://thorax.bmj.com/content/79/2/112
Publication Status
Published
Date Publish Online
2023-12-07