Surviving a second out-of-hospital cardiac arrest was associated with substantially higher 5-year mortality compared to surviving a single event (95% vs 47.3%; P<0.001).
Cohort (n=15,617)
Yes
Does surviving a second OHCA compared to a single OHCA affect 5-year mortality and life-sustaining device use in adult OHCA survivors?
Survivors of a second out-of-hospital cardiac arrest represent a highly vulnerable population with a 95% 5-year mortality rate and greater dependence on life-sustaining devices compared to single OHCA survivors.
Absolute Event Rate: 95% vs 47.3%
p-value: p=<0.001
Background Long-term surveillance of out-of-hospital cardiac arrest (OHCA) survivors is increasingly important, but patients who survive a second OHCA are rarely characterized because of the scarcity of such cases. The nationwide claims-based health data provide an opportunity to identify this uncommon survivor population and evaluate postdischarge outcomes at the population level. Understanding the prognosis and care needs of second-time OHCA survivors may help inform postarrest surveillance, risk stratification, and long-term care planning. Objective This study aimed to compare the clinical characteristics of adult patients who survived a single OHCA versus those who survived a second OHCA during a 5-year follow-up and assess and contrast their 5-year survival outcomes. Methods We conducted a nationwide retrospective cohort study using data from the National Health Insurance Research Database (2010-2020) in Taiwan. Survivors at discharge were classified as 1-OHCA survivors, defined as patients who survived exactly 1 OHCA episode and had no documented recurrent OHCA during follow-up, or 2-OHCA survivors, defined as patients who experienced exactly 2 documented OHCA episodes and survived to discharge after both events. Patients with more than 2 OHCA episodes were excluded. Postdischarge survival was measured from the qualifying discharge date: discharge after the first OHCA for 1-OHCA survivors and discharge after the second OHCA for 2-OHCA survivors. Variables included demographics, comorbidities, health care use, and life-sustaining device status. Five-year mortality was analyzed using the Kaplan-Meier and log-rank tests. Adjusted hazard ratios were derived from multivariable Cox models. Device use patterns were compared using Cochran-Armitage trend tests. Results Among 239,929 OHCA cases, 229,047 were eligible; 15,617 survived to hospital discharge. Five-year mortality was substantially higher among 2-OHCA survivors than among 1-OHCA survivors (191/201, 95% vs 6850/14,494, 47.3%; log-rank P3 outpatient visits, Foley catheter use, and tracheostomy or ventilation were associated with lower observed postdischarge mortality. In the 2-OHCA group, the rate of device-free status was lower, while the triple-device use rate was higher. Conclusions In this nationwide claims-based surveillance study, patients who survived discharge after a second OHCA represented a rare and clinically vulnerable postarrest population with poor subsequent 5-year survival and greater life-sustaining device dependence. Device-related variables should be interpreted as claims-based markers of postdischarge dependency, care setting, survivorship, and care intensity rather than evidence that device placement itself improves survival. As 2-OHCA survivor status is conditional on survival to a second OHCA and discharge after that event, these findings should be interpreted as descriptive and hypothesis-generating rather than causal. Population-level health data may support long-term postarrest surveillance and care planning for rare OHCA survivor populations.
Lin et al. (2026) conducted a cohort in Out-of-hospital cardiac arrest (OHCA) (n=15,617). Second out-of-hospital cardiac arrest (2-OHCA) vs. Single out-of-hospital cardiac arrest (1-OHCA) was evaluated on 5-year mortality (p=<0.001). Surviving a second out-of-hospital cardiac arrest was associated with substantially higher 5-year mortality compared to surviving a single event (95% vs 47.3%; P<0.001).