Risk of hypertension on the incidence of out-of-hospital cardiac arrest.

Objectives: To analyse the effect of hypertension on the occurrence of out-of-hospital cardiac arrest, and to find out whether the effect is dependent on the use of anti-hypertensive drugs.
Methods: The case-control study used secondary data from the Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance project and comprised patients with presumed cardiac aetiology adult out-of-hospital cardiac arrest assessed by emergency medical service from 27 participating emergency departments from January 2016 to December 2017. Controls matched for age, gender and county were recruited from the Korea National Health and Nutrition Examination Survey database in a 4:1 ratio. Multivariate logistic regression analysis was used to analyse the effects of hypertension and the administration of anti-hypertensive medication on out-of-hospital cardiac arrest incidence. Data was analysed using SAS 9.4.
Results: Of the 7330 subjects, 1,466(20%) were patients and 5864(80%) were controls. Hypertension was found in 662(45.2%) patients and 3,190(54.4%) controls. Hypertension lowered the incidence of out-of-hospital cardiac arrest (adjusted odds ratio: 0.69 [95% confidence interval: 0.60-0.80]); in the medication group 0.64(0.55-0.75), and 1.12(0.83-1.49) in the non-medication group.
Conclusions: Administration of anti-hypertensive medications in patients of hypertension may help reduce the incidence of out-of-hospital cardiac arrest. Active hypertension diagnosis and anti-hypertensive medications to reduce the incidence of out-of-hospital cardiac arrest is critical.