Prehospital care affects outcomes after out-of-hospital cardiac arrest (OHCA). The aim of the study is to analyze age-related differences in prehospital care and survival after OHCA and to define variables affecting the efficacy of cardiopulmonary resuscitation (CPR).

Material and methods:
We performed analysis of differences in patient characteristics influencing the efficacy of CPR and analysis of survival in four age groups: < 65, 65–74, 75–84, and ≥ 85. This retrospective registry-based study aimed to compare prehospital care in OHCA patients across age groups.

CPR was performed in 2,500 patients. Return of spontaneous circulation (ROSC) occurred in 1061 subjects. Of them, 339 had incomplete medical records, 201 survived at least 24 h, 115 up to 30 days and 78 were alive at 365 days after discharge. The occurrence of shockable rhythms and the ROSC rate decreased with age. Overall mortality increased with age. Such factors as age, gender, urban area, home location, time to arrival, and witnessed OHCA were predictors of the initial shockable rhythm. Gender, urban area, OHCA witnessed by family member, time to arrival, cardiac cause and shockable rhythm were predictors of ROSC. The risk of death increased with each age group by about 56% (HR = 1.56, p < 0.0001).

Shockable initial rhythm and urban location were the strongest predictors of ROSC. Survival at 30 and 365 days after OHCA decreased in older patients. Survival among older patients with OHCA is worse than in younger subjects, which results from lower efficacy of resuscitation and more frequent death declared upon arrival.