[Epidemiological study on factors relating to chronological fluctuation of blood pressure]

The purpose of this study was to evaluate the factors relating to chronological fluctuation of blood pressure using routine health examination data. The persons observed were general inhabitants aged 30-69 living in a rural town in Tochigi Prefecture. The observation period was from 1979 to 1988, and the cumulative population observed was 23,360 persons. The examination items evaluated were smoking habit, drinking habit, height-weight ratio, urinalysis (sugar and protein), total serum cholesterol, and blood hemoglobin concentration. The incidence of fluctuation in these series was defined as "those whose blood pressure was judged as normal by WHO classification in one year and who was hypertensive in the next year." The risk of developing hypertension was evaluated for the factors under study. The results were summarized as follows: 1. For the height-weight ratio, the relative risk of the 100-119% group was 1.6(p < 0.01), and that of the > 120% group was 2.3(p < 0.01) compared to the control group. 2. For the urinalysis, the relative risk of the group with abnormal urine sugar levels was 1.6(p < 0.05), and that of the urine protein was 3.0(p < 0.01) compared to the control group. 3. For the total serum cholesterol, the relative risk of the 159-199mg/dl group was 2.8(p < 0.01), and that of the > 200mg/dl group was 3.6(p < 0.01) compared to the control group. 4. Obesity, abnormal urinalysis, and high total serum cholesterol were factors relating to chronological fluctuation of blood pressure. 5. Statistically significant differences were not observed for the smoking habit, drinking habit, and blood hemoglobin concentration.