Introduction: Asthma is a prevalent, chronic disease associated with significant risk to patients and cost to healthcare systems. Accurate estimates of length of stay and recovery are important for patient information, physician prognostication, and management of inpatient beds.
Objectives: To assess factors affecting length of stay and time to recovery in adults with acute asthma.
Methods: We prospectively recruited adult asthmatic non-smokers admitted with an asthma exacerbation. Participants were assessed for demographics, symptoms, medications, bloods including blood count, clotting status, and cytokines. Results were analyzed for correlation and subsequently in a regression model.
Results: One hundred twenty-six participants were recruited of which 75.4% were female. Mean age was 40.0 and mean length of stay was 3.98 days. Length of stay was associated with lower APTT ratio (<P = 0.001), oxygen requirement (P = 0.02), increased AST (P = 0.005), increasing age (P = 0.02), and lower %predicted FEV1 (P = 0.02). Longer time to recovery was associated with plasma IL-12 >1 pg/mL (P = 0.04).
Conclusion: Older participants with lower FEV1 and supplemental oxygen requirements are likely to remain in hospital longer. Activation of the "intrinsic" clotting pathway correlates with an increased length of stay as does a raised serum AST. Detectable IL-12 in plasma correlates with slower recovery and this may be due to poor response to corticosteroids.
Keywords: asthma; cytokines; hospitalization; inpatients; interleukin-12; length of stay.
© 2016 John Wiley & Sons Ltd.