Pharmacological treatments in asthma‐affected horses: A pair‐wise and network meta‐analysis

Summary Background Equine asthma is a disease characterised by reversible airflow obstruction, bronchial hyper‐responsiveness and airway inflammation following exposure of susceptible horses to specific airborne agents. Although clinical remission can be achieved in a low‐airborne dust environment, repeated exacerbations may lead to irreversible airway remodelling. The available data on the pharmacotherapy of equine asthma result from several small studies, and no head‐to‐head clinical trials have been conducted among the available medications. Objectives To assess the impact of the pharmacological interventions in equine asthma and compare the effect of different classes of drugs on lung function. Study design Pair‐wise and network meta‐analysis. Methods Literature searches for clinical trials on the pharmacotherapy of equine asthma were performed. The risk of publication bias was assessed by funnel plots and Egger's test. Changes in maximum transpulmonary or pleural pressure, pulmonary resistance and dynamic lung compliance vs. control were analysed via random‐effects models and Bayesian networks. Results The results obtained from 319 equine asthma‐affected horses were extracted from 32 studies. Bronchodilators, corticosteroids and chromones improved maximum transpulmonary or pleural pressure (range: −8.0 to −21.4 cmH2O; P