Obesity, weight change and risks for hypertension, diabetes and hypercholesterolemia in Japanese men

Objective: To examine the effects of the degree of body mass index and weight gain as the risks for hypertension, hypercholesterolemia and diabetes in Japanese men, and to compare that to the corresponding effects in a Caucasian population. Design: Prospective cohort study. Setting: Cohort of all male employees at a company. Subjects: A total of 4737 male employees followed until retirement or for 4y (longest term 4y). Results: Increase of body mass index beyond 22 kg/m(2) related to an increased risk for hypertension even after being adjusted for possible confounding factors such as age, smoking status, alcohol intake, family history and baseline value of systolic blood pressure. The risks greatly increased in subjects with a body mass index above 27 kg/m(2) for hypertension, and 29 kg/m(2) for diabetes and hypercholesterolemia. Weight gain (more than 2 kg) was strongly related to an increased risk for hypertension and hypercholesterolemia after being adjusted for possible confounding factors. However, weight gain was not related to diabetes, and weight loss did not decrease the risks for any of the three diseases. Conclusions: Among Japanese, the degrees of body mass index associated with risks for hypertension, diabetes and hypercholesterolemia were lower than those in Caucasians. The risks for hypertension and hypercholesterolemia were strongly associated with weight gain in a Japanese male population who showed a low prevalence of severe obesity, and the risks were similar to or somewhat higher than those in a Caucasian population with a high prevalence of severe obesity. Sponsorship: Health Science Research Grant by the Ministry of Health and Welfare of Japan.