Seasonal Variation of Blood Pressure in Korean Hypertensives

Shin, Gil Ja; Cho, Hon Keun

Abstract

OBJECTIVES
The mortality rate due to stroke and myocardial infarction by the complication of the hypertension were the major causes of death among the Korean followed by the cancer. There are many factors to affect the blood pressure variability such as physical activity, sleeping, activation of the autonomic nervous system, climate, cold exposure and seasonal variation. The blood pressure was increased by cold exposure. In general, blood pressure was increased in winter and the cardiovascualr mortality is also increased at winter. In Korea, we have distinct seasonal variation of the climate, we have no clinical data on the seasonal variation of the blood pressure.
METHODS
To investigate the seasonal variation of blood pressure of Korean essential hypertensives and make effort to reduce the cardiovascualr mortality, we studied 63 hypertensive men and women hypertensives.
RESULTS
1) The mean age was 60+/-10 years with 19men and 44 women. The mean systolic blood pressure was 146+/-22mmHg, mean diastolic blood pressure was 91+/-11mmHg. 2) The mean systolic and diastolic blood pressure during the 12 months was 137+/-18mmHg, 86+/-10mmHg in men respectively. In women, the mean systolic blood pressure was 137+/-16mmHg and the mean diastolic blood pressure was 86+/-8mmHg. 3) The biochemical findings including hemoglobin, hematocrit and creatinine levels were significantly lower in women(P<0.05). 4) The systolic and diastolic blood pressure were significantly increased during the winter as January and February, 5) There was also significant increase of systolic blood pressure at the transitional zone to the sum- mer to autumn(P=0.0004).
CONCLUSION
There was significant increase in systolic and diastolic blood pressure in winter in Korean hypertensives. This phenomenon was also observed the transitional zone to summer to autumn. So, during these period, more strict blood pressure control by frequent measurement and increase the room temperature may be recommended to reduce the cardiovascular mortality during winter.