Targeted temperature management (TTM) is the standard of care for comatose cardiac arrest survivors. However, evidence regarding its long-term neurological impact specifically on in-hospital cardiac arrest (IHCA) survivors remains limited. This study investigated the association between TTM and the risk of new-onset brain disability in adult IHCA survivors using a “hard” endpoint derived from a national registry.

This nationwide retrospective cohort study utilized the South Korean National Health Insurance Service database (2013-2022). Adult IHCA survivors were categorized into TTM and non-TTM groups. The primary endpoint was newly diagnosed brain disability registered in the Korea National Disability Registration System. This endpoint requires stringent certification by board-certified specialists after at least six months of active treatment to confirm irreversibility. We performed 1:5 propensity score matching and used stratified Cox proportional hazards models to estimate hazard ratios (HR).

Among 95 337 eligible survivors, 31 592 patients were included in the matched cohort (5633 TTM vs 25 959 non-TTM). The TTM group showed a significantly lower incidence of new-onset brain disability compared with the non-TTM group (5.0% vs 5.2%). In the PS-matched analysis, TTM was independently associated with a reduced risk of new-onset brain disability (HR, 0.85; 95% confidence interval [CI], 0.75-0.96; P = .012). Multivariable sensitivity analysis in the entire cohort confirmed this protective association (adjusted HR, 0.80; 95% CI, 0.70-0.90; P < .001).

In this large-scale nationwide cohort of IHCA survivors, TTM implementation was associated with a decreased risk of legally certified, permanent brain disability. These findings provide real-world evidence supporting the continued use of TTM as a neuroprotective strategy to improve long-term quality of survivorship in the IHCA population.