Synergistic acceleration of arterial stiffening in the presence of raised blood pressure and raised plasma glucose.

Arterial stiffness is recognized as a marker of arterial damage and an indicator of cardiovascular risk. This observational study was conducted to examine the synergistic effect of raised blood pressure (RBP; > or =130/85 mm Hg) and raised plasma glucose (RPG; > or =110 mg/dL) even at levels below those conventionally used to define hypertension and diabetes on the rate of increase of the pulse wave velocity (PWV) over a 3-year period in 2080 Japanese men (age 42+/-9 years). First, the subjects were classified into 4 groups based on the presence at the first examination of RBP, RPG, both abnormalities, or neither abnormality. The estimated annual rate of increase of the PWV was higher in subjects with both the abnormalities than in those with either abnormality alone or neither of the 2 abnormalities. Second, the subjects were also classified based on the evolutional status of these abnormalities during the study period; persistence of both of the abnormalities synergistically accelerated the rate of increase of the PWV (68.3+/-7.1 cm/s per year), as compared with the persistence of either abnormality alone (persistence of RBP alone: 18.2+/-1.6 cm/s per year; persistence of RPG alone: 21.2+/-7.4 cm/s per year) or persistence of neither abnormality (11.1+/-0.8 cm/s per year; P<0.01). Thus, blood pressure and fasting plasma glucose levels even below those defining hypertension and diabetes may synergistically lead to progression of arteriosclerotic arterial damage. This synergistic progression may contribute to the additive increases in the risk of cardiovascular events, at least in part.