New study aims to uncover hidden clues in blood pressure control

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Healthy volunteers aged 18-35 years without known acute or chronic disease, non-smokers, body mass index (BMI) 20-24.9 kg/m², and negative orthostatic test * Participants aged ≥60 years with arterial hypertension followed at the Department of Hypertension * Hypertension group: controlled arterial hypertension, negative orthostatic test, without diabetes mellitus * Hypertension with orthostatic hypotension group: controlled arterial hypertension and positive orthostatic test indicating orthostatic hypotension * Hypertension with orthostatic hypertension group: controlled arterial hypertension and positive orthostatic test indicating a rise in blood pressure during orthostatic testing * Hypertension with diabetes mellitus group: controlled arterial hypertension and diabetes mellitus without previously diagnosed autonomic dysfunction * Ability to provide written informed consent Exclusion Criteria: * Dementia, neurodegenerative disease, or cognitive impairment preventing understanding of study procedures * Known cardiovascular disease including heart failure (NYHA II-IV), myocardial infarction within the previous 6 months, clinically significant arrhythmias, or peripheral arterial occlusive disease * Uncontrolled arterial hypertension * Change in antihypertensive therapy within the previous 4 weeks * Presence of a cardiac pacemaker * Treatment with antiarrhythmic drugs (class I, III, or IV), digoxin, alpha-receptor blockers, or other medications known to significantly affect heart rate variability or autonomic function * Advanced renal failure (eGFR \<30 mL/min/1.73 m²) or advanced liver failure * Active malignancy * Body mass index ≥35 kg/m² * Acute illness within the previous 4 weeks * Current smoking * Inability to safely perform exercise testing on a cycle ergometer * Severe psychiatric disorders without stable treatment * Pregnancy or breastfeeding * Participation in another clinical study * Refusal or inability to provide written informed consent