Risk factors for recurrent attacks of wheeze in preschool children: a population-based cohort study in England

<p dir="ltr"><b>Objective To determine factors associated with recurrent attacks of acute wheeze in preschool children.</b></p><p dir="ltr"><br></p><p dir="ltr">Design Retrospective cohort study.</p><p dir="ltr"><br></p><p dir="ltr">Setting English primary electronic health data from the Clinical Practice Research Datalink linked with hospital data from Hospital Episode Statistics.</p><p dir="ltr"><br></p><p dir="ltr">Participants 42 820 children aged 5 years or under with at least one acute wheeze presentation between 1 January 2013 and 31 December 2014.</p><p dir="ltr"><br></p><p dir="ltr">Exposures Demographic and clinical variables including age, sex, ethnicity, deprivation quintile, clinical comorbidities and previous asthma medication prescriptions and acute attacks were included in multivariable analyses.</p><p dir="ltr"><br></p><p dir="ltr">Main outcome measures Further healthcare presentation with an acute wheeze/asthma attack within 12 months.</p><p dir="ltr"><br></p><p dir="ltr">Results Almost 40% (16 962/42 820) of children had a further attack within 12 months. The strongest predictors were hospitalisation with the index episode (RR 1.42; 95% CI 1.39 to 1.45) and an attack in the previous year (1.27; 1.22 to 1.32). Male sex (RR 1.06; 95% CI 1.03 to 1.08), South Asian ethnicity (1.08; 1.04 to 1.12), atopy (1.21; 1.18 to 1.24), prematurity (1.09; 1.04 to 1.14), increasing reliever prescriptions (1.04; 1.03 to 1.04), number of previous attacks (1.03; 1.02 to 1.04) and previous hospitalisation with wheeze (1.09; 1.05 to 1.14) were also associated with further attacks.</p><p dir="ltr"><br></p><p dir="ltr">Older age at presentation (RR 0.92; 0.91 to 0.93) and number of prescriptions for inhaled corticosteroids (0.96; 0.95 to 0.97) in the previous year were associated with lower risk for further attacks.</p><p dir="ltr"><br></p><p dir="ltr">Conclusions Our findings can be used to aid clinical risk prediction for further attacks of wheeze in preschool children.</p>