Factors influencing arterial stiffness in pheochromocytoma and effect of adrenalectomy.

The aim of the study was to evaluate arterial stiffness and its modulating factors measured by carotid-femoral pulse wave velocity (PWV) and central augmentation index (AI) in patients with pheochromocytoma (PHEO) before and after surgery. Forty-five patients with PHEO and 45 healthy controls were investigated using an applanation tonometer (SphygmoCor, AtCor Medical). The gender, age, BMI and lipid profiles were comparable among both groups. The main difference in basic characteristic was as expected for fasting plasma glucose (P<0.001) and all blood pressure modalities. PWV in PHEO was significantly higher than in controls (7.2+/-1.4 vs. 5.8+/-0.5 ms(-1); P<0.001). Between-group difference in PWV remained significant even after the adjustment for age, heart rate, fasting plasma glucose and each of brachial (P<0.001) and 24 h blood pressure parameters (P<0.01). The difference in AI between groups did not reach the statistical significance (19+/-14 vs. 16+/-13%; NS). In multiple regression analysis, age (P<0.001), mean blood pressure (P=0.002), high-sensitive C-reactive protein (hs-CRP) (P=0.007) and 24 h urine norepinephrine (P=0.007) were independently associated with PWV in PHEO. In addition, 27 patients with PHEO were studied 1 year after tumor removal. Successful tumor removal led to a significant decrease in PWV (7.0+/-1.2 vs. 6.0+/-1.1 ms(-1); P<0.001). In conclusion, patients with PHEO have an increase in PWV, which is reversed by the successful tumor removal. Age, mean blood pressure, hs-CRP and norepinephrine levels are independent predictors of PWV.