Abstract 11262: Direct Relationship Between Incidence of Acute Myocardial Infarction and Seismic Intensity in the 2011 East Japan Earthquake and Tsunami Disaster: A Population Based Study
BACKGROUND: Several previous reports showed an increase in the incidence of acute myocardial infarction (AMI) during and after catastrophic earthquakes. However, no reports have demonstrated the combined effect of earthquake and tsunami disaster on the incidence of acute myocardial infarction (AMI).
METHODS: We surveyed the population-based incidence and clinical characteristics of AMI in Iwate prefecture after the catastrophic natural disaster in 2011. In the study area, all patients hospitalized with AMI (MONICA definition-1 criteria) as well as death certificates coded as sudden cardiac death were surveyed retrospectively for 12 weeks (4 weeks before and 8 weeks after the disaster). For comparison with the previous years’ case numbers, an identical survey was conducted in the same area and during the corresponding periods in 2009 and 2010. Weekly maximum seismic intensity (SI) in the survey area was obtained from the Japan Meteorological Agency.
RESULTS: The numbers of cases per week increased from a mean of 9 in 2009 and 2010 to 22 within the first week after the main quake in 2011 (SI = 5.6) and again from 6 to 14 within the first week just after the second quake (SI = 5.5). There was a direct relationship between case numbers per week and maximum SI during the corresponding week (r = 0.75, p < 0.01: Fig). In comparison with previous years, the overall incidence for 4 weeks after the disaster was significantly increased from 29 to 53 cases (odds ratio = 1.88; 95% CI = 1.31 - 2.71: p < 0.001). However, the incidence did not differ between the tsumani-induced high and low refugee areas (odds ratio = 1.01; 95% CI = 0.67 - 1.50: NS). There were also no differences in mean age (80 vs. 77 years), male sex (53% vs. 55%) and inhospital mortality (25% vs 18%) before and after the disaster.
CONCLUSION: The seismicity-related acute stress rather than tsunami-induced living deterioration is a primary trigger of AMI during the earthquake and tsunami disaster.
- © 2013 by American Heart Association, Inc.