Endothelial dysfunction in patients with exaggerated blood pressure response during treadmill test

Background: The diagnostic and prognostic importance of exaggerated blood pressure response to exercise is controversial. Endothelial dysfunction has been demonstrated in patients with atherosclerosis and risk factors for coronary artery disease, but there is a paucity of information on patients with exercise-induced hypertension. Hypothesis: We designed the study to evaluate endothelial function in patients with exaggerated blood pressure response during exercise. Methods: Exercise-induced hypertension was defined as systolic blood pressure greater than or equal to 210 mmHg in men and greater than or equal to 190 mmHg in women during the treadmill test. Using a high-resolution ultrasound technique, endothelial function of the brachial artery in patients with exercise-induced hypertension (n = 25) and control subjects (n = 25) was investigated. Results: Endothelium-dependent vasodilation was impaired in patients with exercise-induced hypertension compared with controls (7.77 +/- 5.14 vs. 2.81 +/- 2.29%, p < 0.05). On univariate analysis, the extent of vasodilation correlated negatively with age (r = -0.43, p < 0.05) and Delta systolic blood pressure (r = -0.39, p < 0.05). Even after adjustment for factors known to affect endothelial function, endothelium-dependent vasodilation was decreased in patients with exercise-induced hypertension (beta = 5.375, p = 0.02). Conclusion: Patients with exercise-induced hypertension have impaired endothelium-dependent vasodilation. This study also supports the concept that endothelial dysfunction may play an important role in exercise-induced hypertension.