Effects of body weight control on changes in blood pressure: three-year follow-up study in young Japanese individuals.

Numerous epidemiological studies have shown a close relationship between obesity and hypertension. However, there have been few reports on the relationship between changes in the body weight and blood pressure of lean to normal-weight young subjects. The purpose of this study was to investigate the effects of body weight control on blood pressure in lean to obese young Japanese individuals in a 3-year follow-up study. University students (3,558 males and 1,418 females, aged 18.6+/-0.8 in 1994) were classified into 4 groups according to the baseline body mass index (BMI), and were followed up for 3 years. Among male students, changes in body weight were significantly correlated with changes in blood pressure during the 3 years in all 4 BMI groups, and the correlation coefficient was larger in the group with higher baseline BMI. Positive correlations between changes in body weight and changes in heart rate were noted only in the obese and mildly-obese groups. Also in female students, positive correlations were observed between changes in body weight and changes in blood pressure in lean to obese groups. However, no correlations between changes in body weight and changes in heart rate were noted in any of the female groups. To summarize, close correlations were observed between changes in body weight and those in blood pressure during the 3 years in both male and female university students. These findings suggest the importance of body weight control not only in obese but also in normal to mildly-obese young subjects in reducing or preventing an increase in blood pressure. There could be, however, a gender difference in the effects of body weight change on heart rate.