Targeted temperature management (TTM) is recommended for all comatose adult out-of-hospital cardiac arrest (OHCA) patients with shockable first documented rhythm. However, studies examining the use and benefits of TTM among patients aged 75 and older are lacking. Using the Cardiac Arrest Registry to Enhance Survival (CARES) dataset registry from 2013 to 2015. Study criteria included being 75 years of age or older, survival to hospital admission, and known in-hospital mortality and CPC (Cerebral Performance Categories Scale) Scores. The study outcomes were in-hospital mortality and poor neurologic outcomes (CPC Scores 3 or 4) at hospital discharge among survivors. Hierarchical logistic regression and propensity score matching were used for multivariable adjustment. Two thousand nine hundred eighty-two patients met study inclusion criteria. One thousand three hundred fifty-seven (45.5%) received TTM in the admitting hospital. Receipt of TTM was more likely among men, those with a shockable first documented rhythm, and those with their event witnessed. There was no significant association with TTM and in-hospital mortality among patients with ventricular fibrillation (odds ratio [OR] = 0.88; 95% confidence interval [CI] [0.62-1.25]), p = 0.487 within the cohort. However, patients with a nonshockable first rhythm receiving TTM had higher odds of in-hospital mortality (p < 0.001). Propensity score results showed a modest association with TTM and increased mortality (OR) = 1.22, 95% CI [1.01-1.47]; p = 0.036 and no association with poor neurologic outcome (OR = 1.18; 95% CI [0.82-1.69]; p = 0.379) in the elderly. TTM is often provided to OHCA patients over age 75 though the benefits, particularly among nonshockable first documented rhythm patients are unclear. A randomized trial is needed to definitively answer who among OHCA event survivors aged 75 and older should receive this treatment.
Keywords: effectiveness; elderly; hypothermia; targeted temperature management; therapeutic.