February 15, 1996New England Journal of Medicine830 citationsOpen Access
View Full PaperSudden Cardiac Death Triggered by an Earthquake
Key Result
The Northridge earthquake significantly increased sudden cardiac deaths to 24 on the day of the event, compared to a daily average of 4.6 in the preceding week (P<0.001).
Study Design
Type
Observational
Structured PICO
Does exposure to an earthquake and its associated emotional stress trigger sudden cardiac death in predisposed individuals?
P
Population
Records from the Los Angeles County Department of Coroner were reviewed to assess sudden cardiac deaths before, during, and after the 1994 Northridge earthquake.
E
Exposure
Exposure to the Northridge earthquake (January 17, 1994) and associated emotional stress.
C
Comparator
Control periods including the week before the earthquake, the six days after the earthquake, and corresponding control periods in 1991, 1992, and 1993.
O
Outcome
Number of sudden deaths from cardiac causes related to atherosclerotic cardiovascular disease.hard clinical
Severe emotional stress from a major earthquake significantly triggers sudden cardiac death in individuals predisposed to atherosclerotic cardiovascular disease.
Main Result
Absolute Event Rate: 24% vs 4.6%
p-value: p=<0.001
Abstract
BACKGROUND: The earthquake that struck the Los Angeles area at 4:31 a.m. on January 17, 1994, was one of the strongest earthquakes ever recorded in a major city in North America. Once the life-threatening situation was over, the Northridge earthquake, so called because its epicenter was near Northridge, California, just north of Los Angeles, provided investigators an unusual opportunity to examine the relation between emotional stress and sudden cardiac death. METHODS: We reviewed the records of the Department of Coroner of Los Angeles County for the week before the earthquake, the day of the earthquake, the six days after the earthquake, and corresponding control periods in 1991, 1992, and 1993. RESULTS: On the day of the earthquake, there was a sharp increase in the number of sudden deaths from cardiac causes that were related to atherosclerotic cardiovascular disease, from a daily average (+/- SD) of 4.6 +/- 2.1 in the preceding week to 24 on the day of the earthquake (z = 4.41, P < 0.001). Sixteen victims of sudden death had symptoms, usually chest pain, or died within the first hour after the initial tremor. Only three sudden deaths occurred during or immediately after unusual physical exertion. During the six days after the earthquake, the number of sudden deaths declined to below the base-line value, to an average of 2.7 +/- 1.2 per day. CONCLUSIONS: The Northridge earthquake was a significant trigger of sudden death due to cardiac causes, independently of physical exertion. This finding, along with the unusually low incidence of such deaths in the week after the earthquake, suggests that emotional stress may precipitate cardiac events in people who are predisposed to such events.