Blood pressure and vascular function response to maximal graded exercise tests in young men with masked hypertension

Abstract

Individuals with masked hypertension have out-of-office blood pressure (BP) readings in the hypertensive range, but office BP readings below the hypertensive cutoff, making masked hypertension less likely to be diagnosed. The aim of this study was to determine whether in-laboratory measurements of BP and vascular function in response to exercise can serve as indicators of masked hypertension in young adults. Thirty-three young men with office BP <130/80 mmHg, free of smoking and clinical diseases, were included in this study. All participants underwent 24-h ambulatory BP monitoring for BP classification, as well as in-laboratory BP and vascular assessments at rest and after a maximal graded exercise test on a cycle ergometer. These assessments included peripheral and central BP, arterial stiffness, wave reflection, and endothelial function. Compared to participants without masked hypertension (CON; n = 17), those with masked hypertension (MH; n = 16) had a higher level of 24-h, daytime, and nighttime systolic BP (P ≤ 0.005), but similar office BP (P ≥ 0.5). No differences between groups were found in peripheral BP and vascular function measurements at baseline (P ≥ 0.2) and in response to exercise (P ≥ 0.2 for group by time interaction effects). Although central systolic BP at rest was similar between groups (P = 0.17), MH had a higher marginal mean of central systolic BP from resting, following exercise, and during recovery (MH vs. CON: 113 ± 2 vs. 108 ± 2 mmHg, P = 0.047 for group effect). These findings suggest that in young men, masked hypertension may be associated with an elevated central systolic BP, which could be induced by exercise.NEW & NOTEWORTHY We show for the first time that in young men, peripheral blood pressure (BP) and vascular function in response to maximal graded exercise tests were not different between individuals with and without masked hypertension. On the other hand, in young men, masked hypertension may be associated with an elevated central systolic BP, which could be induced by exercise.

Keywords: acute exercise; ambulatory blood pressure; cardiovascular risk factors.

Figure 1.

Group means and individual data for supine blood pressure (BP) measures at baseline (BL), immediately after a maximal graded exercise test on a cycle ergometer (EX), and during recovery (REC; ~30-min after exercise) in young men with masked hypertension (n=16, solid lines) versus young men without masked hypertension (n=17, dash lines). A: central systolic BP (cSBP). B: central diastolic BP (cDBP). C: central pulse pressure (cPP). D: peripheral systolic BP (pSBP). E: peripheral diastolic BP (pDBP). F: peripheral pulse pressure (pPP). P values are from two-way ANOVA with repeated measure. P < 0.05 indicates statistical significance (highlighted in bold). Black lines indicate group mean ± SD and gray lines indicate individual data.

Figure 2.

Group means and individual data for vascular function measures at baseline (BL), after a maximal graded exercise test on a cycle ergometer (EX; within 15 min after exercise), and during recovery (REC; ~30-min after exercise) in young men with masked hypertension (solid lines; MH) versus young men without masked hypertension (dash lines; CON). A: carotid-to-femoral pulse wave velocity (cfPWV; n=17 CON and 16 MH). B: augmentation index (AIx; n=17 CON and 16 MH). C: reflection magnitude (RM; n=16 CON and 15 MH). D: flow-mediated dilation (FMD; n=15 CON and 16 MH). P values are from two-way ANOVA with repeated measure. P < 0.05 indicates statistical significance (highlighted in bold). Black lines indicate group mean ± SD and gray lines indicate individual data.