Background: Understanding the long-term outcomes after out-of-hospital cardiac arrest (OHCA) is important to understand the overall health burden of OHCA. Disability-adjusted life years (DALY) have recently been utilised to measure disease burden in OHCA, but data in Asia remains limited. We aimed to quantify long-term survival in OHCA and the annual disease burden of OHCA estimated using DALYs in a national multi-ethnic Asian cohort.
Methods: We conducted an open cohort study through linking the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS) and the Singapore Registry of Births and Deaths from 2010 to 2019. We quantified long-term survival using standardised mortality ratio (SMR) for each year of follow up and the annual disease burden using DALYs. Predictors of long-term survival were identified using Cox-proportional hazards models.
Results: We included 802 cases in the analysis. The mean age was 56.0 (SD 17.8) and the majority was male (631 cases, 78,7%) and of Chinese ethnicity (552 cases, 68.8%). At one year, the SMR was 14.9 (95%CI: 12.5-17.8), and this decreased to 1.2 (95%CI: 0.7-1.8) at three years, and 0.4 (95%CI: 0.2-0.8) at five years. Age at arrest (HR:1.03, 95%CI: 1.02-1.04, p<0.001), shockable first arrest rhythm (HR:0.75, 95%CI: 0.52-0.93, p=0.015) and CPC category (HR:4.62, 95%CI: 3.17-6.75, p<0.001) were independently associated with mortality. The annual DALYs due to OHCA varied from 304.1 in 2010 to 849.7 in 2015, then to 547.1 in 2018. The mean DALY decreased from 12.162 in 2010 to 3.599 in 2018.
Conclusions: OHCA survivors had an increased mortality rate compared to the general population for the first three years, which subsequently normalised to that of the general population. Annual disease burden of OHCA in DALY trended downwards from 2010 to 2018. Improved surveillance and OHCA treatment strategies may improve long-term survivorship and decrease the global burden of OHCA.