Background Pulse pressure (PP) reflects pulsatile blood flow which is responsible for mechanical stress on blood vessels. There are some evidence that specific organ involvement in hypertension is related rather to PP than to the levels of systolic or diastolic blood pressure. The aim of the study was to investigate to relation between PP and selected biochemical risk factors of cardiovascular complication in patients with primary hypertension.
Material and methods A total of 128 hypertensive patients (pts) of age 24–82 yr (av. 58.2 ± 12.3) and 21 healthy subjects of age 19-79 yr (av. 52.8 ± 12.7) were studied. 24-hours automatic blood pressure measurement were performed in each patient and healthy subject. Pts were grouped according to level of PP as follows: 20 pts with PP < 55 mm Hg, 40 with PP 56-65 mm Hg, 36 with PP 66-75 mm Hg and 32 with PP > 75 mm Hg. In all pts creatinine levels, crea-tinine clearance, microalbuminuria, glucose level, lipid metabolism, hematocrit and fibrinogen level were measured.
Results Creatinine levels in group III and IV were increased compared to group with lower PP (p < 0.05). Creatinine clearance in groups with PP > 55 mm Hg was lower compared to group I and controls (respectively p < 0.01 and p < 0.001). In groups with PP > 65 mm Hg there was significant increase of microalbuminuria compared to group I and controls (respectively p < 0.01, p < 0.001). Moreover high correlation between PP and microalbuminuria ( r = 0.47, p < 0.001) was found. In groups with PP > 55 mm Hg increase of total cholesterol level and LDL fraction compared to controls (p < 0.01, p < 0001 respectively) was observed. Level of HDL in group IV was diminished compared to controls (p < 0.05), as well as to group II (p < 0.01) and III (p < 0.05). Glucose and fibrinogen plasma level in groups with PP > 55 mm Hg were increased compared to controls and group I.
Conclusion Significant increase of creatinine levels, increase of microalbuminuria in pts with high PP compared to groups with lower PP, and strong, positive correlation between PP and extent of microalbuminuria suggests essential role of PP in development of nephropathy in hypertensive patients and indicates particular importance of microalbuminuria as predictor of renal damage in hypertension. Performed study indicates, that PP > 65 mm Hg is predictive factor for cardiovascular complications in primary hypertension.