Effect of the Hanshin-Awaji earthquake on home blood pressure in patients with essential hypertension.

At 5:46 AM on January 17, 1995, the Hanshin-Awaji district of Japan was struck by a major earthquake. We investigated changes in home blood pressure (BP) of 36 hypertensive patients before and after the earthquake. In the 16 patients who lived within 50 km from the epicenter, the home Bp on the day of the earthquake was significantly higher than that just before the earthquake (+11/+6 mm Hg; P < .01 for systolic BP and P < .05 for diastolic BP). It remained higher throughout the first week after the earthquake, then gradually returned to the baseline level within 4 weeks. The home BP did not change significantly in the 20 patients who lived farther than 50 km from the epicenter. The earthquake-induced stress increased the BP in these hypertensive patients; however, its pressor effect was not persistent.