OBJECTIVE: To investigate whether structured aerobic exercise increases brain vessel lumen diameter or cerebral blood flow (CBF) and whether lumen diameter is associated with CBF.
DESIGN: Open, parallel, two-arm superiority randomized controlled (1:1) trial in the TEPHRA study on an intention-to-treat basis. The MRI sub-study was an optional part of the protocol. The outcome assessors remained blinded until the data lock.
SETTING: Single-centre trial in Oxford, UK.
PARTICIPANTS: Participants were physically inactive (<150 min/week moderate to vigorous physical activity), 18 to 35 years old, 24-hour ambulatory blood pressure 115/75 mmHg-159/99 mmHg, body mass index below 35 kg/m2 and never been on prescribed hypertension medications. Out of 203 randomized participants, 135 participated in the MRI sub-study. Randomisation was stratified for sex, age (<24, 24-29, 30-35 years) and gestational age at birth (<32, 32-37, >37 weeks).
INTERVENTION: Study participants were randomised to a 16 week aerobic exercise intervention targeting 3×60 min sessions per week at 60 to 80 % peak heart rate.
MAIN OUTCOMES AND MEASURES: cerebral blood flow (CBF) maps from ASL MRI scans, internal carotid artery (ICA), middle cerebral artery (MCA) M1 and M2 segments, anterior cerebral artery (ACA), basilar artery (BA), and posterior cerebral artery (PCA) diameters extracted from TOF MRI scans.
RESULTS: Of the 135 randomized participants (median age 28 years, 58 % women) who had high quality baseline MRI data available, 93 participants also had high quality follow-up data available. The exercise group showed an increase in ICA (0.1 cm, 95 % CI 0.01 to 0.18, p =.03) and MCA M1 (0.05 cm, 95 % CI 0.01 to 0.10, p =.03) vessel diameter compared to the control group. Differences in the MCA M2 (0.03 cm, 95 % CI 0.0 to 0.06, p =.08), ACA (0.04 cm, 95 % CI 0.0 to 0.08, p =.06), BA (0.02 cm, 95 % CI -0.04 to 0.09, p =.48), and PCA (0.03 cm, 95 % CI -0.01 to 0.06, p =.17) diameters or CBF were not statistically significant. The increase in ICA vessel diameter in the exercise group was associated with local increases in CBF.
CONCLUSIONS AND RELEVANCE: Aerobic exercise induces positive cerebrovascular remodelling in young people with early hypertension, independent of blood pressure. The long-term benefit of these changes requires further study.
TRIAL REGISTRATION: Clinicaltrials.gov NCT02723552, 30 March 2016.
OBJECTIVES: This study sought to assess the impact of catheter-based RDN on TTR and its association with cardiovascular outcomes in the GSR (Global SYMPLICITY Registry).
METHODS: Patients with uncontrolled hypertension were enrolled and treated with radiofrequency RDN. Office and ambulatory systolic blood pressure (OSBP and ASBP) were measured at 3, 6, 12, 24, and 36 months postprocedure and used to derive TTR. TTR through 6 months was assessed as a predictor of cardiovascular events from 6 to 36 months using a Cox proportional hazard regression model.
RESULTS: As of March 1, 2022, 3,077 patients were enrolled: 42.2% were female; mean age was 60.5 ± 12.2 years; baseline OSBP was 165.6 ± 24.8 mm Hg; and baseline ASBP was 154.3 ± 18.7 mm Hg. Patients were prescribed 4.9 ± 1.7 antihypertensive medications at baseline and 4.8 ± 1.9 at 36 months. At 36 months, mean changes were -16.7 ± 28.4 and -9.0 ± 20.2 mm Hg for OSBP and ASBP, respectively. TTR through 6 months was 30.6%. A 10% increase in TTR after RDN through 6 months was associated with significant risk reductions from 6 to 36 months of 15% for major adverse cardiovascular events (P < 0.001), 11% cardiovascular death (P = 0.010), 15% myocardial infarction (P = 0.023), and 23% stroke (P < 0.001).
CONCLUSIONS: There were sustained BP reductions and higher TTR through 36 months after RDN. A 10% increase in TTR through 6 months was associated with significant risk reductions in major cardiovascular events from 6 to 36 months. (Global SYMPLICITY Registry [GSR] DEFINE; NCT01534299).