Deciphering the Mechanisms of Central BP Regulation in Patients With PD Associated With Orthostatic Hypotension
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Lower body negative pressure.
- Who it may be relevant to
- Registry conditions: Parkinson Disease, Orthostatic Hypotension. Basic parameters: 18 years — 75 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Switzerland
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Deciphering the Mechanisms of Central Blood Pressure Regulation in Patients With Parkinson Disease Associated With Orthostatic Hypotension: A 2-phase Observational Study With Healthy Participants and Patients With Parkinson's Disease
Overview
Phase 1 objective: test the feasibility of using a 3Tesla MRI scanner instead of a 7Tesla MRI scanner to measure brainstem responses to LBNP in healthy participants. Phase 2 primary objective: compare the brainstem responses to LBNP in patients with PD associated with OH to PD patients without OH using BOLD fMRI
Detailed description
Phase 1 objective: test the feasibility of using a 3Tesla MRI scanner instead of a 7Tesla MRI scanner to measure brainstem responses to LBNP in healthy participants using BOLD fMRI
Phase 2 primary objective: compare the brainstem responses to LBNP in patients with PD associated with OH to PD patients without OH using BOLD fMRI
Phase 2 secondary objectives:
* assess modulation of functional connectivity in response to LBNP (effective connectivity analysis by psycho-physiological interactions (PPI)) and determine differences between the two groups * assess functional connectivity in resting state and determine differences between the two groups * compare structural connectivity in both groups using tractography * compare renal response to LBNP in both groups using contrast-enhanced ultrasound * compare pre-cerebral flow response to LBNP in both groups
Interventions
- Diagnostic test Lower body negative pressure
LBNP is a technique that redistributes blood from the upper body to the dependent regions of the legs, thus reducing central venous pressure and venous return and thereby activating the sympathetic nervous system (SNS). The subject is placed in a cylindrical airtight tank, which is sealed at the level of the iliac crests, and sub-atmospheric pressure is produced using a vacuum pump. It can be used to characterize the cardiovascular responses to orthostatic stress
Primary outcome measures
- Differences and changes in BOLD fMRI signal intensity [Time frame: 1.5 hour]
Secondary outcome measures (4)
- Functional connectivity [Time frame: 1.5 hour]
- Structural connectivity [Time frame: 30 minutes]
- Contrast-enhanced renal ultrasound [Time frame: 1.5 hour]
- pre-cerebral blood flow [Time frame: 30 minutes]
Eligibility criteria
Phase 1:
Inclusion criteria
- Signed informed consent
- Age ≥ 18 years and <75 years
- Normal office blood pressure (<140/90 mmHg)
- For women of childbearing potential: using or willing to use during the study a reliable contraception method compatible with MRI
Exclusion criteria
- Schellong test showing OH (drop of Systolic BP >20 mmHg or Diastolic BP >10 mmHg)
- Pregnant or lactating women
- Refusal to be informed of incidental findings
- Any medication (acute or chronic prescription) except oral contraception
- Clinical significant abnormal blood test as assessed by the investigator
- Chronic or acute illness
- Concomitant participation in a clinical trial
- Blood donation in the 60 previous days
- Contra-indications for MRI
- Unable to follow study procedures
- Having a hierarchical relationship with the investigator or being family of the investigator
Phase 2:
Inclusion criteria
- Signed informed consent
- Fulfilling Movement Disorder Society clinical criteria for "clinically established PD"
- Age ≥18 years and <75 years
- PD treated by dopamine replacement therapy (DRT)
- Willing and able to comply with the visit schedule and study procedures
- Autonomous in daily life
- Schellong test showing OH (drop of Systolic BP >20 mmHg or Diastolic BP >10 mmHg)(for study group with OH) or no OH (for studygroup without OH)
- For women of childbearing potential: using or willing to use during the study a reliable contraception method compatible with MRI
Exclusion criteria
- Unable to give an informed consent
- BP > 180/110 mmHg on 24-hour ambulatory blood pressure monitoring
- eGFR < 45 ml/min/1.73 ml/min/m2 by CKD-EPI equation
- having contra-indications for MRI
- Pregnant or lactating women
- Refusal to be informed of incidental findings
- Allergy to components of contrast agent Sonovue®
- Living in an institution
- Dementia
- Type 2 diabetes
- Stroke or myocardial infarction in the past 6 months
- Blood donation in the previous 6 months
- Active oncology treatment
- Having a hierarchical relationship with the investigator or being family of the investigator
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Observational model
- Case-control
Study locations
Switzerland · 1 center
- Centre Hospitalier Universitaire Vaudois — Lausanne
Identifiers
NCT: NCT07139756 · 2024-01828