Sex-related disparities in post-cardiac arrest: a cohort study

Predicting neurological outcomes after successful resuscitation remains a major challenge in post-cardiac arrest (CA) care. Biological sex has been proposed as prognostic factor, but existing data are conflicting. This study assessed sex-related differences in CA characteristics, prognostic indicators, mortality, and long-term neurological outcomes.

We analyzed data from a prospective registry of consecutive comatose adults admitted after CA to the Lausanne University Hospital (CHUV) between January 2016 and February 2025, surviving the first 24 h. Post-resuscitation care followed international guidelines. Prognosis included ICU mortality and, at 3 months, mortality and favorable outcome, defined as modified Rankin Scale (mRS) 0-3. Sex differences were analyzed using univariable tests and multivariable logistic regressions adjusting for cardiac arrest characteristics.

Among 944 included patients (28.6% women, mean age 62 ± 15 years), women more often presented with non-cardiac etiology and non-shockable rhythm. They exhibited more malignant EEG patterns, absent SSEP, and higher serum NSE levels. Favorable neurological outcome occurred in 39.6% of women vs. 48.0% of men (p = 0.013). After adjustment, however, sex was not independently associated with ICU mortality (OR 1.08, 95% CI: 0.80-1.46), 3-month mortality (OR 1.05, 95% CI: 0.77-1.43), or favorable functional outcome (OR 1.00, 95%: CI: 0.73-1.37).

Although women presented with worse unadjusted outcomes and more severe prognostic profiles, sex was not independently related to neurological recovery and mortality. Outcome differences likely reflect less favorable underlying cardiac arrest characteristics.