Sudden cardiac death in marathons: a systematic review

Area of Science:

• Cardiology
• Sports Medicine
• Epidemiology

Background:

• Sudden cardiac death (SCD) is a critical concern in endurance events like marathons.
• Existing systematic reviews on SCD incidence in marathons are lacking.
• Understanding SCD risk in marathon participants requires rigorous data analysis.

Purpose of the Study:

• To systematically review and summarize cohort studies on SCD incidence in marathons.
• To critically assess the methodological quality of studies reporting SCD in marathon runners.
• To identify limitations in current data collection and reporting practices for marathon-related SCD.

Main Methods:

• Conducted a systematic literature search of multiple databases (Medline, CINAHL, SPORTDiscus, Google Scholar) and manual searches.
• Included 7 cohort studies published between 1966 and 2014, covering a large runner population.
• Analyzed reported incidence rates, demographic data (sex, age), and methodological aspects of the included studies.

Main Results:

• The incidence of SCD in marathons varied widely, ranging from 0.6 to 1.9 per 100,000 runners.
• Included studies involved over 200,000 runners, with SCD recorded in 4 to 28 individuals.
• A high proportion of SCD cases were male (57.1%–100%), with a mean age of 37–48 years.

Conclusions:

• Significant methodological concerns exist regarding data collation, timing of death, sample size estimation (registrants vs. runners), and exercise history details.
• These limitations threaten the reliability and interpretation of reported SCD incidence rates in marathons.
• Recommendations include improving data collection methods and establishing a central reporting system for marathon-related SCD.