Seasonal variation in bystander efforts and survival after out-of-hospital cardiac arrest

IF 2.1 Q3 CRITICAL CARE MEDICINE

Resuscitation plus Pub Date : 2025-03-22 DOI:10.1016/j.resplu.2025.100934

Niels Saaby Hald , Harman Yonis , Mathias Hindborg , Helle Collatz Christensen , Jannie Kristine Bang Gram , Erika Frischknecht Christensen , Fredrik Folke , Gunnar Gislason , Christian Torp-Pedersen , Kristian Bundgaard Ringgren

{"title":"Seasonal variation in bystander efforts and survival after out-of-hospital cardiac arrest","authors":"Niels Saaby Hald , Harman Yonis , Mathias Hindborg , Helle Collatz Christensen , Jannie Kristine Bang Gram , Erika Frischknecht Christensen , Fredrik Folke , Gunnar Gislason , Christian Torp-Pedersen , Kristian Bundgaard Ringgren","doi":"10.1016/j.resplu.2025.100934","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div>This study investigated the hypothesis that out-of-hospital cardiac arrest (OHCA) incidence, public automated external defibrillator (PAD) utilization and outcome vary by season, with increased incidence and lower survival rates expected in winter. The aim was to provide insights that might optimize resuscitation efforts throughout the year.</div></div><div><h3>Methods</h3><div>Cases of OHCA from 2016 to 2021 were included from the Danish Cardiac Arrest Registry. Cases were stratified by season and month and analysed for frequency, witnessed status, location, bystander cardiopulmonary resuscitation (CPR), bystander PAD defibrillation and 30-day survival. The primary outcome was incidence of OHCA and variability in utilization of PADs by season. Secondary outcome was 30-day survival rates. Categorical variables were compared using Chi-square and multivariable analyses were conducted using Poisson regression.</div></div><div><h3>Results</h3><div>A total of 25,248 OHCA cases were included with a median age of 74 years [IQR 63–82] and 64% were male. Multivariable analyses revealed a lower incident rate ratio (IRR) of OHCA for most months (IRR 0.78 to 0.92 with 95%CI 0.72–0.98, all p-values < 0.05), except March and December, using January as reference. Seasonal rates of bystander CPR (78.4%–79.4%, <em>p</em> = 0.414) and PAD shock (8.9%–9.8%, <em>p</em> = 0.266) remained consistent throughout the year. The proportion of residential OHCAs were higher during winter than in summer (79.4% vs 77.5%, respectively, <em>p</em> = 0.023). Crude 30-day survival rates showed significant seasonal variation with lower survival rates during winter (11.1%) compared to spring (12.4%), summer (13.4%) and fall (12.2%, <em>p</em> = 0.001). However, after adjusting for factors such as sex, comorbidities, and OHCA circumstances (witnessed status, bystander CPR, PAD shock), no significant seasonal variation in survival remained (all <em>p</em> > 0.05).</div></div><div><h3>Conclusion</h3><div>Incidence of OHCA was higher in winter, but rates of bystander CPR and PAD shock remained consistent across seasons. Crude mortality rates were significantly lower during winter. However, multivariable regression analysis revealed no significant variation in survival rates by month.</div></div>","PeriodicalId":94192,"journal":{"name":"Resuscitation plus","volume":"23 ","pages":"Article 100934"},"PeriodicalIF":2.1000,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Resuscitation plus","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666520425000712","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CRITICAL CARE MEDICINE","Score":null,"Total":0}

引用次数: 0

Abstract

Background

This study investigated the hypothesis that out-of-hospital cardiac arrest (OHCA) incidence, public automated external defibrillator (PAD) utilization and outcome vary by season, with increased incidence and lower survival rates expected in winter. The aim was to provide insights that might optimize resuscitation efforts throughout the year.

Methods

Cases of OHCA from 2016 to 2021 were included from the Danish Cardiac Arrest Registry. Cases were stratified by season and month and analysed for frequency, witnessed status, location, bystander cardiopulmonary resuscitation (CPR), bystander PAD defibrillation and 30-day survival. The primary outcome was incidence of OHCA and variability in utilization of PADs by season. Secondary outcome was 30-day survival rates. Categorical variables were compared using Chi-square and multivariable analyses were conducted using Poisson regression.

Results

A total of 25,248 OHCA cases were included with a median age of 74 years [IQR 63–82] and 64% were male. Multivariable analyses revealed a lower incident rate ratio (IRR) of OHCA for most months (IRR 0.78 to 0.92 with 95%CI 0.72–0.98, all p-values < 0.05), except March and December, using January as reference. Seasonal rates of bystander CPR (78.4%–79.4%, p = 0.414) and PAD shock (8.9%–9.8%, p = 0.266) remained consistent throughout the year. The proportion of residential OHCAs were higher during winter than in summer (79.4% vs 77.5%, respectively, p = 0.023). Crude 30-day survival rates showed significant seasonal variation with lower survival rates during winter (11.1%) compared to spring (12.4%), summer (13.4%) and fall (12.2%, p = 0.001). However, after adjusting for factors such as sex, comorbidities, and OHCA circumstances (witnessed status, bystander CPR, PAD shock), no significant seasonal variation in survival remained (all p > 0.05).

Conclusion

Incidence of OHCA was higher in winter, but rates of bystander CPR and PAD shock remained consistent across seasons. Crude mortality rates were significantly lower during winter. However, multivariable regression analysis revealed no significant variation in survival rates by month.

查看原文本刊更多论文

院外心脏骤停后旁观者的努力和存活率的季节性变化

本研究调查了院外心脏骤停（OHCA）发生率、公共自动体外除颤器（PAD）使用率和结果随季节变化的假设，预计冬季发病率增加，生存率降低。其目的是提供可能优化全年复苏工作的见解。方法纳入2016 - 2021年丹麦心脏骤停登记处的OHCA病例。病例按季节和月份分层，并分析频率、目击状态、地点、旁观者心肺复苏（CPR）、旁观者PAD除颤和30天生存率。主要结局是OHCA的发生率和不同季节使用pad的变异性。次要终点为30天生存率。分类变量比较采用卡方法，多变量分析采用泊松回归法。结果共纳入25248例OHCA，中位年龄74岁[IQR 63 ~ 82]，男性占64%。多变量分析显示，大多数月份OHCA的发生率比（IRR）较低(IRR 0.78 ~ 0.92, 95%CI 0.72 ~ 0.98， p值均为<；0.05)，除3月和12月外，均以1月为参照。旁观者CPR （78.4% ~ 79.4%, p = 0.414）和PAD休克（8.9% ~ 9.8%,p = 0.266）的季节性发生率全年保持一致。冬季居民ohca比例高于夏季（分别为79.4%和77.5%,p = 0.023）。粗30天存活率存在显著的季节差异，冬季（11.1%）低于春季（12.4%）、夏季（13.4%）和秋季（12.2%,p = 0.001）。然而，在调整了性别、合并症和OHCA情况（目击状态、旁观者CPR、PAD休克）等因素后，生存率没有明显的季节性变化(所有p >；0.05)。结论冬季OHCA的发生率较高，但旁观者CPR和PAD休克的发生率在各个季节保持一致。粗死亡率在冬季显著降低。然而，多变量回归分析显示，按月生存率无显著差异。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊