Abstract
BACKGROUND: The importance of assessing out-of-hospital cardiac arrest (OHCA) risk in cancer patients is increasing as cancer incidence rises in aging populations. OBJECTIVE: This study aimed to investigate the association between newly diagnosed cancer and OHCA risk using a metropolitan cohort from South Korea. METHODS: A population-based retrospective cohort study was conducted, linking the nationwide OHCA registry with the National Health Information Database. The study included adults aged 40 years or older, residing in Seoul between 2015 and 2018, with no history of cancer or OHCA. The main exposure was cancer development. The primary outcome was the occurrence of OHCA with medical cause. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were calculated using a cause-specific hazard model considering death as a competing risk. Analyses stratified by age group and cancer type were also conducted. RESULTS: During a follow-up period of up to 4 years for 5,450,438 individuals, 174,785 participants developed cancer. The incidence rates of OHCA per 100,000 person-years were 54.0 in non-cancer and 145.0 in cancer groups, respectively. The aHR (95% CI) for OHCA associated with cancer development was 3.18 (2.97-3.41). The aHR (95% CI) for OHCA was highest in the 40-49 years of age group (7.52 [5.52-10.25]), followed by 50-59 years old (6.66 [5.56-7.97]) compared to older age groups. By cancer type, pancreatic, lung, biliary tract, and liver cancer were associated with a significantly increased risk of OHCA. CONCLUSION: We found an association between newly diagnosed cancer and the occurrence of OHCA. Our findings underscore the importance of tailored risk assessments and proactive care planning for patients with cancer.