Laboratory of Exercise Physiology, School of Physical Education, State University of Campinas, Brazil.
Institute of Inflammation and Ageing, University of Birmingham, UK.
Exerc Immunol Rev. 2024;30:6-13.
Several studies have reported that marathon runners have a higher risk of upper respiratory tract infections (URTI) post marathon than non-exercising controls. However, other studies did not find a higher risk of URTI in the same participants before and after a marathon, precluding a conclusive consensus. Besides the between-subjects effects, another important confounding factor in these results is the different pre and post follow-up time to track URTI.
Identify by meta-analysis whether a marathon Running increases the risk of URTI, adjusting the follow-up time to track URTI.
We searched for articles using MEDLINE (PubMed), Embase, Scopus, Web of Science, the Cochrane Library, and EBSCOhost, combining the marathon and respiratory infection descriptor synonyms, on 1st December 2022.
The PICOS framework included human population, comparison between pre and post marathon running, of URTI symptoms (assessed from one to 4 weeks), in noncontrolled intervention studies.
Because follow-up was longer before the marathon in many studies, we adjusted the number of subjects with infections before marathon to the equivalent post-marathon follow-up duration. There was 18% higher incidence of URTI post-marathon (OR 1.18 95%CI [1.05-1.33], p= 0.005) in a very consistent meta-analysis (I2 = 0%, p = 0.69), with no risk of publication bias (Egger test p-value = 0.82) for the 7 studies included. The main issues with quality of the studies were bias in measuring the outcome, bias in classification of intervention (participation in the marathon) and time-varying confounding (corrected for analysis), and therefore the quality of evidence was moderate (GRADE approach = 3).
The need for follow-up time adjustment is a limitation, since the number of URTI recorded could be different if the original studies had used the same follow-up time pre and post marathon. The subjectivity of the URTI assessments is another limitation in this field.
There is an increased risk of URTI post marathon running and research on this topic to understand mechanisms might support runners to find efficient interventions to reduce this risk.
Protocol registration on in the International Prospective Register of Systematic Reviews (PROSPERO): CRD42022380991.
多项研究报告称，马拉松运动员在马拉松赛后患上呼吸道感染（URTI）的风险高于不运动的对照组。然而，其他研究并没有发现同一参与者在马拉松前后的 URTI 风险更高，这使得结论不一致。除了个体间的影响外，这些结果中另一个重要的混杂因素是跟踪 URTI 的预随访和后随访时间不同。
通过荟萃分析确定马拉松跑步是否会增加 URTI 的风险，并调整跟踪 URTI 的随访时间。
我们于 2022 年 12 月 1 日使用 MEDLINE（PubMed）、Embase、Scopus、Web of Science、Cochrane 图书馆和 EBSCOhost 等数据库，结合马拉松和呼吸道感染描述符同义词，搜索文章。
PIECoS 框架纳入了人群、马拉松前后的 URTI 症状比较（评估时间为 1 至 4 周）、非对照干预研究。
由于许多研究中马拉松前的随访时间更长，我们将马拉松前感染人数调整到相当于马拉松后的随访时间。在一项非常一致的荟萃分析中，马拉松后 URTI 的发生率高出 18%（OR 1.18，95%CI [1.05-1.33]，p=0.005）（I2=0%，p=0.69），不存在发表偏倚的风险（Egger 检验 p 值=0.82），纳入了 7 项研究。研究质量的主要问题是对结果的测量存在偏倚、对干预（参加马拉松）的分类存在偏倚以及时间变化性混杂（经分析校正），因此证据质量为中等（GRADE 方法=3）。
需要进行随访时间调整，因为如果原始研究在马拉松前后使用相同的随访时间，记录的 URTI 数量可能会有所不同。在该领域，URTI 评估的主观性也是一个局限性。
马拉松后 URTI 的风险增加，对这一主题的研究可能有助于跑步者找到减少这种风险的有效干预措施。
该方案在国际前瞻性系统评价注册库（PROSPERO）进行了注册：CRD42022380991。
