Haemodynamic determinants of hYpertension in Children and Young People and role of the sympathetic nervous system: HY CYP
Paediatrics and cardiology
Current methodology as of 07/08/2026: PARTICIPANTS Children and young adults with primary hypertension aged 10-35 years will be approached by a member of their direct clinical care team. We aim to recruit 75 patients, 50% under 18 years and 50% 18-35 years, with 50% female. Participants should not be on medication (i.e., are managing their hypertension with lifestyle modification measures). If they are on medication, they need to be able to stop their medication for a 2-week washout period before the study and stay off their medication until the collection of all data (up to 2 months), in the opinion of their lead clinician. For Study 2, we will seek to recruit 20 hypertensive patients from the original Study 1 cohort, at the point at which they will be commencing antihypertensive medication for clinical reasons. 50 control participants aged 10-35 years will be recruited from existing databases of healthy controls. These participants have previously participated in clinical studies with our group and have consented to be contacted about further studies in the future. We aim to recruit 50 patients, 50% under 18 years and 50% 18-35 years, with 50% female. They will need to be of normal blood pressure and healthy weight, i.e., not overweight, or obese. Another 25 control participants will be consented prospectively to ensure adequate recruitment to all sub-tests in the study. STUDY 1 (all participants) Data to be collected is as follows, with no specific order necessary: 1. Height, weight, BMI, and measures of adiposity. Pubertal status for those who have not yet completed puberty. 2. Standardised depression and anxiety questionnaire 3. Blood test: kidney function, measures of sympathetic nervous system activity, measures of heart function, metabolic markers 4. Urine test: sodium (salt) levels, measures of sympathetic nervous system activity 5. Cardiac MRI: 40-minute MRI scan of the heart with blood pressure measured before and after the scan 6. Blood pressure, heart
1. Aged 10-35 years old 2. Primary hypertension (intervention group) or BP < 90th centile (control group) 3. Able to tolerate the planned investigations 4. Not currently on anti-hypertensive medication/s or able to stop anti-hypertensive medications for 2 weeks prior to any research-related assessments. Additional inclusion criteria control participants: 5. BMI in the "normal" range for age
1. Secondary hypertension 2. Clinical urgency to commence anti-hypertensive or unable to stop anti-antihypertensives for 2 week washout period 3. Unable to obtain adequate quality of planned cardiovascular investigations 4. Congenital heart disease 5. Cardiac dysrhythmias 6. Pregnancy or lactating mothers Additional exclusion criteria for medication 1 (bisoprolol challenge): 7. Asthma currently treated with medication 8. Cardiac conduction abnormalities 9. Known intolerance to bisoprolol Additional exclusion criteria for medication 2 (amlodipine challenge): 10. History of angina or myocardial infarction 11. Known intolerance to amlodipine