Objective: A retrospective case-control study at Monash Medical Centre (MMC), a tertiary referral hospital in Melbourne, Australia, was conducted to identify risk factors associated with very severe asthma in paediatric patients.
Methodology: Asthmatics admitted to an intensive care unit (ICU; n=52) were identified and considered to represent cases of very severe/near fatal asthma (NFA group). This group was compared to asthmatics who had been admitted on one occasion only to the emergency department at MMC (non-NFA controls, n=53). Patient files were examined and factors that may be linked to NFA were recorded. Information not on file was obtained from patients/parents during a structured telephone interview. Data for the two groups were compared, univariate and multivariate logistic regression analyses were performed, and odds ratios (OR) were calculated.
Results: Univariate analysis indicated that asthmatics with NFA were more likely to be older (P=0.01) and have a longer duration of asthma (P=0.02). They were also more likely to have hay fever (P=0.002; OR, 7.6), use inhaled corticosteroids (P=0.001), long acting beta(2) agonists (P=0.02), have an asthma management plan (P=0.006), and see a respiratory specialist (P=0.001). Parental smoking habits were not different between the groups. Multivariate logistic regression analysis identified male gender (P=0.05; OR, 5.7) and use of inhaled corticosteroids (P=0.07; OR, 7.2) as factors that may be predictive of NFA.
Conclusions: This study identifies a number of factors associated with NFA; many are similar to those reported in adult patients. Asthma severity explains some findings, but the data also suggest that additional independent risk factors such as gender and duration of asthma may operate in children.