Age-related differences of blood pressure profile in essential hypertension.

The purpose was to assess age-related circadian changes of blood pressure profile (BPP) employing a truncated Fourier series with four harmonics (tFs) in patients with essential hypertension. The study was performed on 32 patients with essential hypertension divided in two groups: (A) 15 patients younger than 55 years and (B) 17 patients older than 60 years. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored every 20 minutes for 24 h with a noninvasive portable device (SpaceLabs 90202). To evaluate the existence of SBP and DBP circadian rhythms a one-sample runs-test was performed and the mesor, amplitude, and acrophase from the overall curve of each patient were obtained by tFs. In both groups, SBP and DBP profiles showed a first peak in the late morning and a second peak in the early evening around the same hours. The two peaks in the SBP profile were higher and the two peaks in the DBP profile were lower in older patients than in younger ones (p < .01, p < .05, p < .3, p < .05). The truncated Fourier series with four harmonics evidences different age-related BP profiles characterized by two peaks with higher SBP and lower DBP in elderly patients. These changes of BPP are in accordance with the reported higher risk of cardiovascular events observed around the same hours.

The structural arteriolar changes in diabetes mellitus and essential hypertension. The relative contribution of ageing and high blood pressure.

AIM: To evaluate the relative contribution of blood pressure, non-insulin dependent diabetes mellitus and ageing on arteriolar structural changes in essential hypertension and diabetes mellitus. POPULATION AND METHODS: One hundred subjects, 25 with hypertension (A), 25 with hypertension and diabetes (B), 25 with diabetes (C) and 25 healthy subjects (D). Blood pressure average values, obtained with non-invasive monitoring, and minimal vascular resistance, calculated with strain-gauge plethysmography, were statistically correlated. Multiple regression analysis was performed to assess the contribution of blood pressure and age. RESULTS: Minimal vascular resistance was higher in A, B and C than in D, and higher in B than in A and C. The coefficient of blood pressure in the multiple regression analysis was significant for all the parameters in A and B but not in C and D; that of age was significant only in A and only for the average values of mean and diastolic blood pressure. CONCLUSION: Hypertension and diabetes show arteriolar structural changes of similar gravity. Age does play a role in hypertension but a smaller one than that played by blood pressure. In hypertension and diabetes the lack of significance of the contribution of age to the correlation between minimal vascular resistance and pressure could be ascribed to other neurohumoral factors. These factors play a much more important role in diabetes; where neither blood pressure nor age show any correlation with high vascular resistance.