Overweight Body Mass Index Classification Modifies Arterial Stiffening Associated with Weight Gain in Healthy Middle-Aged Japanese Men

The present study was conducted to clarify whether body mass index (BMI [kg/m2]) classifications (i.e., without excess weight, overweight, and obese) modify the rate of progression of arterial stiffening, a cardiovascular risk factor associated with weight gain. A 3-year observational study was conducted in 2,080 healthy middle-aged Japanese men (aged 42±10 years). Brachial-ankle pulse wave velocity (baPWV) was measured at the beginning and end of the study period. In overweight subjects (30>BMI≥25), the estimated annual rate of increase of baPWV (ARbaPWV) in subjects with weight gain (≥5% weight gain; ARbaPWV, 21.8±4.4 cm/s/year) was significantly higher than in those without weight gain (<5% weight gain; ARbaPWV, 12.5±1.6 cm/s/year), after adjustments for changes in blood pressure and other variables (p<0.05). This change was not observed in subjects without excess weight (BMI<25) or in obese subjects (BMI≥30). The increase in the ARbaPWV associated with weight gain in the overweight group was also higher than that in the without excess body weight or obese groups. Our study revealed that the BMI classifications modified the annual rate of increase in arterial stiffening associated with weight gain. Weight gain seemed to accelerate arterial stiffening in overweight subjects, but not in subjects without excess weight. The weight gain in overweight subjects seemed to worsen the cardiovascular risk related to arterial stiffness in middle-aged healthy Japanese men. Thus, the prevention of weight gain should be emphasized in overweight subjects.