Epinephrine (adrenaline) compared to selective beta-2-agonist in adults or children with acute asthma: a systematic review and meta-analysis.

BACKGROUND: International asthma guidelines recommend against epinephrine (adrenaline) administration in acute asthma unless associated with anaphylaxis or angio-oedema. However, administration of intramuscular epinephrine in addition to nebulised selective ß2-agonist is recommended for acute severe or life-threatening asthma in many prehospital guidelines. We conducted a systematic review to determine the efficacy of epinephrine in comparison to selective ß2-agonist in acute asthma. METHODS: We included peer-reviewed publications of randomised controlled trials (RCTs) that enrolled children or adults in any healthcare setting and compared epinephrine by any route to selective ß2-agonist by any route for an acute asthma exacerbation. The primary outcome was treatment failure, including hospitalisation, need for intubation or death. RESULTS: Thirty-eight of 1140 studies were included. Overall quality of evidence was low. Seventeen studies contributed data on 1299 participants to the meta-analysis. There was significant statistical heterogeneity, I2=56%. The pooled Peto's OR for treatment failure with epinephrine versus selective ß2-agonist was 0.99 (0.75 to 1.32), p=0.95. There was strong evidence that recruitment age group was associated with different estimates of the odds of treatment failure; with studies recruiting adults-only having lower odds of treatment failure with epinephrine. It was not possible to determine whether epinephrine in addition to selective ß2-agonist improved outcomes. CONCLUSION: The low-quality evidence available suggests that epinephrine and selective ß2-agonists have similar efficacy in acute asthma. There is a need for high-quality double-blind RCTs to determine whether addition of intramuscular epinephrine to inhaled or nebulised selective ß2-agonist improves outcome. PROSPERO REGISTRATION NUMBER: CRD42017079472.

What matters most to patients when choosing treatment for mild-moderate asthma? Results from a discrete choice experiment.

BACKGROUND: An as-needed combination preventer and reliever regimen was recently introduced as an alternative to conventional daily preventer treatment for mild asthma. In a subgroup analysis of the PRACTICAL study, a pragmatic randomised controlled trial of budesonide-formoterol reliever therapy versus maintenance budesonide plus terbutaline reliever therapy in adults with mild asthma, we recently reported that about two-thirds preferred as-needed combination preventer and reliever therapy. The aim of this study was to determine the relative importance of attributes associated with these two asthma therapies in this subgroup of participants who indicated their preferred treatment in the PRACTICAL study. METHODS: At their final study visit, a subgroup of participants indicated their preferred treatment and completed a discrete choice experiment using the Potentially All Pairwise RanKings of all possible Alternatives method and 1000minds software. Treatment attributes and their levels were selected from measurable study outcomes, and included: treatment regimen, shortness of breath, steroid dose and likelihood of asthma flare-up. RESULTS: The final analysis dataset included 288 participants, 64% of whom preferred as-needed combination preventer and reliever. Of the attributes, no shortness of breath and lowest risk of asthma flare-up were ranked highest and second highest, respectively. However, the relative importance of the other two attributes varied by preferred therapy: treatment regimen was ranked higher by participants who preferred as-needed treatment than by participants who preferred maintenance treatment. CONCLUSIONS: Knowledge of patient preferences for treatment attributes together with regimen characteristics can be used in shared decision-making regarding choice of treatment for patients with mild-moderate asthma. TRIAL REGISTRATION NUMBER: ACTRN12616000377437.