CT-derived subcutaneous adipose tissue thickness and circulating adipokines in relation to neurological outcome after in-hospital cardiac arrest: two parallel cohort analyses

Background Hypoxic–ischemic brain injury is a major determinant of outcome after in-hospital cardiac arrest (IHCA). Adipose tissue may be relevant to post-arrest outcomes through its anatomical and endocrine characteristics. We conducted two parallel exploratory analyses to examine the associations of thoracic subcutaneous adipose tissue depth and circulating adipokines with neurological outcome after IHCA. Method We employed a dual-cohort design. The CT Imaging Cohort included patients with pre-arrest and post-arrest thoracic CT examinations. Associations of anterior and posterior subcutaneous adipose tissue thickness with survival and neurological outcome at hospital discharge were evaluated. In the Biochemical Cohort, plasma concentrations of 12 adipokines measured during cardiac arrest were compared between neurological outcome groups. Multiple comparisons were controlled using the Benjamini–Hochberg false discovery rate procedure. Exploratory logistic regression models were evaluated using discrimination, calibration, bootstrap internal validation, and Firth regression sensitivity analysis. Results In the CT Imaging Cohort, several unadjusted differences in post-arrest posterior subcutaneous adipose tissue thickness were observed between neurological outcome groups, but none remained statistically significant after false discovery rate correction in the overall analysis. In the ventilation-matched sensitivity analysis, greater pSAT thickness at selected thoracic levels remained associated with favorable neurological outcome after correction for multiple comparisons. In the Biochemical Cohort, CTRP6, CTRP9, Omentin-1, and Vaspin concentrations were higher and Chemerin concentration was lower in patients with favorable neurological outcomes after false discovery rate correction. The apparent AUC was 0.876 (95% CI, 0.795–0.957) for the clinical model and 0.938 (95% CI, 0.882–0.993) for the exploratory model adding CTRP6. The AUC difference was not statistically significant (ΔAUC, 0.062; 95% CI, −0.003 to 0.126; P = 0.062). The optimism-corrected AUC of the extended model was 0.930. Conclusion CT-derived posterior subcutaneous adipose tissue thickness and circulating adipokines showed exploratory associations with neurological outcome in two independent IHCA cohorts. The addition of CTRP6 to CPR duration and lactate numerically improved model discrimination, but the incremental AUC was not statistically significant. These findings are hypothesis-generating and require external validation. Because CT measurements and adipokines were obtained from different patients, the study does not establish a direct anatomical–biochemical relationship.