Around a third of children under the age of 5 years old experience 'wheeze', this is the term used for a high pitch whistling sound heard when breathing out. Sometimes wheeze is due to the common lung disorder asthma, but diagnosing asthma in this age group is challenging as they cannot do certain tests. Parents want to know if their child will continue to wheeze, if they have asthma and will they need treatment. This study hopes to help answer these questions. Previous studies have used surveys to try to answer these questions, but not all people like to answer surveys and sometimes people can't remember the answer, whereas GP data is fairly nationally and does not require people to remember past events. We will use this data to see for the first time, how common wheeze is in pre-school children in England, what kind of children have wheeze, and how likely they are to develop asthma during school age (5 years old onwards), and at what age. We will also look at some factors (e.g. treatment) that might influence whether a child is more or less likely to develop asthma as an older child.
The objective of this study is to measure, over the past two decades, the prevalence of preschool wheeze (wheeze in children aged under 5 years), describe these children in terms of demographics and relevant clinical features; then estimate the rate of progression to school-age asthma, and the determinants of that progression. Annual prevalence of preschool wheeze will be calculated and stratified by age, gender, and co-diagnosis of asthma using validated asthma Read codes. Patients with be identified by the presence of one or more Read codes for wheeze. Patients will be described in terms of demographics, clinical characteristics, and treatment, at 5 different calendar years (2000, 2005, 2010, 2015 and 2017) to inform on differences over the past two decades. A cohort design will be used to estimate the rate of progression of preschool wheeze to school-age asthma, and the ages at which progression occurs. Determinants that may increase the rate of progression will be assessed; these will include demographics (e.g. age, birth weight), clinical characteristics (e.g. atopy, bronchiolitis), or treatment given (e.g. inhaled steroids). A Poisson regression model will be used to estimate rates for each variables, allowing adjustment for all other covariates.
Preschool wheeze prevalence
- School-age asthma diagnosis
Jennifer Quint - Chief Investigator - Imperial College London
Chloe Bloom - Corresponding Applicant - Imperial College London
Sejal Saglani - Collaborator - Imperial College London
CPRD Mother-Baby Link;HES Accident and Emergency;HES Admitted Patient Care;Patient Level Index of Multiple Deprivation;Pregnancy Register