Imperial College London, London, UK.
Imperial College Healthcare NHS Trust, London, UK.
Open Heart. 2024 Jun 18;11(1):e002669. doi: 10.1136/openhrt-2024-002669.
Neurocardiogenic syncope is a common condition with significant associated psychological and physical morbidity. The effectiveness of therapeutic options for neurocardiogenic syncope beyond placebo remains uncertain.
The primary endpoint was the risk ratio (RR) of spontaneously recurring syncope following any therapeutic intervention. We also examined the effect of blinding on treatment efficacy. We identified all randomised trials which evaluated the effect of any pharmacological, device-based or supportive intervention on patients with a history of syncope. A systematic search was conducted on Medline, Embase, PubMed databases and Cochrane Central Register for Controlled Trials from 1950 to 25 April 2023. Event rates, their RRs and 95% CIs were calculated, and a random-effects meta-analysis was conducted for each intervention. Data analysis was performed in R using RStudio.
We identified 47 eligible trials randomising 3518 patients. Blinded trials assessing syncope recurrence were neutral for beta blockers, fludrocortisone and conventional dual-chamber pacing but were favourable for selective serotonin reuptake inhibitors (SSRIs) (RR 0.40, 95% CI 0.26 to 0.63, p<0.001), midodrine (RR 0.70, 95% CI 0.53 to 0.94, p=0.016) and closed-loop stimulation (CLS) pacing (RR 0.15, 95% CI 0.07 to 0.35, p<0.001). Unblinded trials reported significant benefits for all therapy categories other than beta blockers and consistently showed larger benefits than blinded trials.
Under blinded conditions, SSRIs, midodrine and CLS pacing significantly reduced syncope recurrence. Future trials for syncope should be blinded to avoid overestimating treatment effects.
CRD42022330148.
神经心源性晕厥是一种常见病症，与显著的心理和生理发病率相关。神经心源性晕厥的治疗选择除了安慰剂之外的有效性仍然不确定。
主要终点是任何治疗干预后自发复发性晕厥的风险比（RR）。我们还检查了盲法对治疗效果的影响。我们确定了所有评估任何药物、器械或支持干预对有晕厥史的患者影响的随机试验。从 1950 年到 2023 年 4 月 25 日，我们在 Medline、Embase、PubMed 数据库和 Cochrane 对照试验中心进行了系统检索。计算了事件发生率、RR 和 95%CI，并对每种干预措施进行了随机效应荟萃分析。数据分析在 R 中使用 RStudio 进行。
我们确定了 47 项符合条件的试验，共纳入 3518 名患者。评估晕厥复发的盲法试验对β受体阻滞剂、氟氢可的松和传统双腔起搏结果为中性，但对选择性 5-羟色胺再摄取抑制剂（SSRIs）（RR 0.40，95%CI 0.26 至 0.63，p<0.001）、米多君（RR 0.70，95%CI 0.53 至 0.94，p=0.016）和闭环刺激（CLS）起搏（RR 0.15，95%CI 0.07 至 0.35，p<0.001）有有利影响。非盲法试验报告了所有治疗类别的显著益处，除了β受体阻滞剂，并且始终显示出比盲法试验更大的益处。
在盲法条件下，SSRIs、米多君和 CLS 起搏显著降低了晕厥复发率。未来的晕厥试验应进行盲法，以避免高估治疗效果。
PROSPERO 注册号：CRD42022330148。
