In this analysis of the data from a longitudinal study on coronary heart disease risk factors, it was found that participants screened a few weeks after a major disaster (earthquake) had a higher heart rate, serum cholesterol levels, and serum triglyceride levels than matched participants that were screened shortly before the catastrophic event. The two groups of participants did not differ with regard to their characteristics at the baseline examination carried out 5 years previously. The lack of difference in blood pressure between exposed and nonexposed participants could be explained by the lag-time between the earthquake and the blood pressure measurements. We conclude that the acute stress associated with major disasters can influence risk factors for coronary heart disease. Permanent elevation of these risk factors due to the disruption of the social environment of the individuals affected by major disasters might be responsible for the apparent long-term adverse effects on cardiovascular mortality discussed previously in the literature.