2011 Japan Earthquake Linked To Spike In Cardiovascular Events

Researchers from Tohoku University have shown a sharp increase in the incidence of cardiovascular conditions soon after the Japanese earthquake and tsunami of March 11, 2011.

AsianScientist (Aug. 30, 2012) – Researchers from Tohoku University have shown a sharp increase in the incidence of cardiovascular conditions soon after the Japanese earthquake and tsunami of March 11, 2011, which hit the north-east coast of Japan with a magnitude of 9.0 on the Richter scale.

The tsunami caused huge damage to the region, including 15,861 dead and 3,018 missing persons, and, as of June 6, 2012, 388,783 destroyed homes.

Led by cardiologist Dr. Hiroaki Shimokawa and colleagues from the Tohoku University Graduate School of Medicine at Sendai, Japan, the team examined all ambulance transport records in the Miyagi prefecture four weeks before to 16 weeks after March 11 for each year from 2008 to 2011.

The Miyagi prefecture is close to the epicenter of the earthquake and where the damage was greatest. Aftershocks were frequently recorded during the six weeks after the earthquake, and the second peak was noted as a large aftershock on April 7, 2011 (magnitude of 7.0).

Based on a total of 124,152 records from before, during and after the earthquake disaster, they found that the weekly occurrence of five cardiovascular conditions – heart failure, acute coronary syndrome (ACS, including unstable angina and acute MI), stroke, cardio-pulmonary arrest and pneumonia – all increased sharply soon after the earthquake occurred.

Compared with the previous three years, there were significant and prolonged increases in the occurrence of heart failure and pneumonia for more than six weeks after the tsunami struck.

On the other hand, the incident increases in stroke and cardio-pulmonary arrest followed the pattern of the first and aftershock seismic peaks. The rapid increases in the occurrence of ACS and cardio-pulmonary arrest was followed by a sharp and significant decline.

Interestingly, age, sex, or residence area did not significantly affect the occurrences of CVD during or following the tsunami, said Shimokawa.

Many people had significantly elevated blood pressure readings after the earthquake; The interrupted delivery of regular medications, such as antihypertensive or antithrombotic drugs, may have contributed to the increased cardiovascular events, the authors say.

There was also an increase in the occurrences of ventricular tachyarrhythmias in patients with implantable cardiac defibrillators.

“To the best of our knowledge,” Shimokawa said, “this is the first report to describe the mid-term course of major cardiovascular events and pneumonia after a great earthquake in a large population. In particular, our findings provide the first evidence that the incidence of heart failure was markedly increased over a long period afterwards.”

——

Source: European Society of Cardiology; Photo: Lucie_Ottobruc/Flickr.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist