This study was carried out to suggest preventive methods for hypertension in cold-exposed workers.

In 11 refrigeration industries, 68 workers working in refrigerated areas more than one time per day were selected as the exposed group, and 68 workers not exposed to cold were selected as the control group. We interviewed the subjects with a questionnaire covering occupational history, and conducted clinical and laboratory tests including measurements of blood pressure and core temperature.

The systolic blood pressure in the exposed group(130.0+/-13.3 mmHg) was significantly higher than that recorded in the control group(118.3+/-12.1 mmHg), as was the diastolic blood pressure in the exposed group(82.7+/-8.5 mmHg) versus the control group(77.4 +/-8.7 mmHg). The core temperature in the exposed group(36.1+/-0 . 7degrees C) was significantly lower than that experienced in the control group(36.4+/-0 . 5degrees C). In logistic regression analysis, age, cold exposure severity and milk intake were significant variables, with odds ratios of 5.204(95 % CI 1.440~18.812), 2.674(95 % CI 1.080~6.618), and 0.364(95 % CI 0.141~0.942), respectively.

Our study suggests that cold-exposed workers have higher a higher risk of hypertension, and that their core temperature is lower. Risk factors affecting hypertension of cold-exposed workers include age, cold exposure severity and milk intake. For the prevention of hypertension, cold-exposed workers should minimize cold-exposure time as much as possible.