Long-term survival following out-of-hospital cardiac arrest in women and men: Influence of comorbidities, social characteristics, and resuscitation characteristics

Aim
We aimed to study sex differences in long-term survival following out-of-hospital cardiac arrest (OHCA) compared to the general population, and determined associations for comorbidities, social characteristics, and resuscitation characteristics with survival in women and men separately.

Methods
We followed 2,452 Danish (530 women and 1,922 men) and 1,255 Dutch (259 women and 996 men) individuals aged ≥25 years, who survived 30 days post-OHCA in 2009–2015, until 2019. Using Poisson regression analyses we assessed sex differences in long-term survival and sex-specific associations of characteristics mutually adjusted, and compared survival with an age- and sex-matched general population. The potential predictive value was assessed with the Concordance-index.

Results
Post-OHCA survival was longer in women than men (adjusted incidence rate ratio (IRR) for mortality 0.74, 95%CI 0.61–0.89 in Denmark; 0.86, 95%CI 0.65–1.15 in the Netherlands). Both sexes had a shorter survival than the general population (e.g., IRR for mortality 3.07, 95%CI 2.55–3.70 and IRR 2.15, 95%CI 1.95–2.37 in Danish women and men). Higher age, glucose lowering medication, no dyslipidaemia medication, unemployment, and a non-shockable initial rhythm were associated with shorter survival in both sexes. Cardiovascular medication, depression/anxiety medication, living alone, low household income, and residential OHCA location were associated with shorter survival in men. Not living with children and bystander cardiopulmonary resuscitation provision were associated with shorter survival in women. The Concordance-indexes ranged from 0.51 to 0.63.

Conclusions
Women survived longer than men post-OHCA. Several characteristics were associated with long-term post-OHCA survival, with some sex-specific characteristics. In both sexes, these characteristics had low predictive potential.