Therapeutic options for syncope: a meta-analysis of trials with and without placebo control

Abstract Funding Acknowledgements Type of funding sources: None. Background 8% the population suffer recurrent episodes syncope which can cause physical injury and psychological morbidity. The extent to therapeutic options effectively reduce recurrence beyond placebo remain unclear. Methods We performed a meta-analysis randomised trials including pharmacological, cardiac pacing interventions for syncope. assessed effect these on clinical recurrence. stratified by use control. Results There were 50 eligible trials: 22 pacing, 19 pharmacological 9 3,975 patients. Trials assessing with control neutral Beta-Blockers (RR 1.11, 95% CI 0.85 1.45, p=0.36), Fludrocortisone, 0.83, CI: 0.63 1.11 p=0.83) conventional dual-chamber 0.81, 0.61 1.09 p=0.287). However, they favourable Selective Serotonin Reuptake Inhibitors [SSRIs] 0.40, 0.25 p<0.001), Midodrine 0.70, 0.53 0.94, p=0.016) Closed-Loop-Stimulation (CLS) 0.21, 0.12 0.34, p < 0.001). Non-placebo-controlled reported significant benefit every category therapy medicines (Beta-Blockers, Oral rehydration salts) tilt-training. Three categories have been trialled without control: non-placebo-controlled studies showed significantly different results from their placebo-controlled counterparts (beta-blockers p=0.024, midodrine p=0.006, p=0.017) (figure 2). Conclusion Under conditions, CLS reduces risk ~75%, whereas does not. SSRIs also show efficacy under conditions. Without control, consistently artefactually larger benefits. Future should not be conducted.