Abstract 174: Weekly Variation in Out-of-Hospital Cardiac Arrests in a Nationwide Japanese Patient Population: Analysis of a Nationwide Population-Based Registry
Background: It is well known that acute cardiovascular events and sudden cardiac death occur most frequently in the morning. There are few reports about weekly variation recently. This study aimed to determine whether there is a weekly variation in the presentation of all-Japan cohort of patients with out-of-hospital cardiac arrests, and if there are significant factors that may affect weekly variability, and if there is a weekly variation in the survival patients.
Methods: We referred to a database of a prospective, nationwide, population-based registry of out-of-hospital cardiac arrests that was compiled by the Fire and Disaster Management Agency of Japan between 2005 and 2010. The records are based on the standardized Utstein style. Patients who had sudden collapse witnessed by family members, friends, or bystanders of the public were enrolled. We assessed the incidence of the cardiac arrest as daily data (i.e., weekly variation) and differences in age, gender. In addition, prognosis was evaluated in terms of survival at 1 month with good or moderate cerebral performance (Cerebral Performance Category; CPC1-2).
Results: During the 6-year period, 670,313 patients were registered nationwide. 147,217 patients had cardiogenic out-of-hospital cardiac arrests witnessed by bystanders and were enrolled for assessment. A gradual weekly rhythm was seen with one zenith in Sunday and one nadir was in Wednesday. There were no remarkable differences in the weekly pattern between men and women. But in working generation (20-79years), even though the peak in men on Sunday, women had a single peak on Monday. Younger (<20 years) patients and older (>80 years) patients had not more apparently weekly rhythm than working generation.
The number of survivors at 1-month with CPC1-2 had a large weekly variation in Sunday. Men had more apparent weekly variation than women in the survivors. There were gender differences in survival ratio; 7.4% of the men, 3.9% of the women (6.1% of the all patients).
Conclusions: Out-of-hospital cardiac arrests in Japanese patients had weekly variation with one zenith on Sunday and survivors as well. There exists a different weekly rhythm of out-of-hospital cardiac arrests patients between men and women, particularly in working generation.
- © 2012 by American Heart Association, Inc.