Uric acid and fibrinogen: age-modulated relationships with blood pressure components.

Data from a cross-sectional population-based study carried out in the town of Bollate (Milan) were used to verify whether there is an age-modulated relationship between the components of blood pressure (BP) and plasma uric acid and fibrinogen levels. Changes in uric acid and fibrinogen levels in relation to diastolic BP (DBP), systolic BP (SBP), mean arterial pressure (MAP) and pulse pressure (PP) in 820 subjects aged 42-59 years and in 509 subjects aged 60-74 years were estimated from general linear models adjusted by the clinical, lifestyle and biological variables traditionally associated with cardiovascular risk. Uric acid levels significantly increased with DBP and MAP only in the middle-aged group without metabolic syndrome or diabetes, and were even in those who were pre-hypertensive. On the contrary, fibrinogen levels significantly increased with SBP and PP only among the elderly with metabolic syndrome or diabetes, and were particularly high among those with stage 2 hypertension. These findings add evidence concerning an age-modulated relationship between the levels of uric acid and fibrinogen and the steady and pulsatile components of BP and it is possibly related to the different mechanisms underlying increased BP: renal factors in middle-aged subjects and vascular abnormalities in the elderly.