Clinical trial Recruiting at 1 site Interventional Ages 50 and up

Effects of Blood Pressure on Thinking and Brain Blood Flow in Parkinson's Disease

Official title: Effects of Blood Pressure on Cognition and Cerebral Blood Flow in Parkinson Disease

Run by University of California, San Diego · NCT05400174 · Data updated 2026-11-12

This study is testing how low blood pressure affects thinking and blood flow in the brains of people with Parkinson's disease who have trouble standing up.

More Parkinson Disease trials

Quick facts

Study typeInterventional
Ages50 Years and up
SexAll
Enrollment60 (estimated)
SponsorUniversity of California, San Diego
Academic / other
Locations1 site (San Diego, California)
StatusRecruiting
StartedDecember 14, 2021
Main results expectedDecember 15, 2026
Study endsJanuary 15, 2027
Registry record updatedAugust 7, 2026
Trial IDNCT05400174 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates for this study are individuals aged 50 and older with a diagnosis of idiopathic Parkinson's disease in early to moderate stages.

Probably not a fit

Patients with severe involuntary movements, dementia, or those who have undergone deep brain stimulation surgery may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This study investigates how blood pressure affects cognitive function and brain blood flow in individuals with Parkinson's disease (PD) who also experience orthostatic hypotension (OH). Participants will undergo a series of clinical assessments, including a tilt table test to confirm the presence of OH and various cognitive evaluations. The goal is to understand the relationship between low blood pressure and cognitive issues that occur when standing, which may not present with typical symptoms. This research aims to identify potential treatment strategies for managing OH in PD patients.

Why it matters

Potential benefit: If successful, this study could lead to improved management of cognitive symptoms in Parkinson's disease by addressing orthostatic hypotension.

How similar studies have gone: While the relationship between blood pressure and cognition in PD is being explored, this specific approach to understanding OH's impact on cognitive function is relatively novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Diagnosis of idiopathic Parkinson Disease using the Movement Disorders Society (MDS) Clinical Diagnostic Criteria
2. Age at least 50 years old
3. Hoehn \& Yahr (H\&Y) stages I-III (early to moderate-stage PD; able to walk without assistance
4. Proficiency in the English language (native English speaker level)

Exclusion Criteria:

1. Any involuntary movements (i.e., tremor or dyskinesia) \> 3 cm in amplitude (ok if movements are treated with medication), since the motion artifact could interfere with blood pressure monitor data collection
2. Dementia (including PD dementia)
3. History of deep brain stimulation (DBS) surgery
4. Any current unstable, active medical problem, e.g. decompensated heart failure, liver failure, pneumonia, etc.
5. Moderate or severe carotid artery stenosis (according to North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria
6. History of cerebral infarction or hemorrhage
7. Uncontrolled diabetes or any other systemic disease causing autonomic failure
8. Syncope (fainting) within the past week
9. Illiteracy (unable to read)
10. Taking antihypertensive medications or alpha-adrenergic blocking medications, since these can cause hypotension (see \* below)
11. Impairment of hearing or vision that is not corrected by devices (e.g., hearing aids or glasses)
12. Currently pregnant (will be confirmed by women of child-bearing potential with a urine pregnancy test)
13. Any other condition, which, in the opinion of the investigator, could place the participant at increased risk.

    * Please note that persons may not participate if they are taking any of the following:

      * medications to treat high blood pressure (called "antihypertensives") such as clonidine (Catapres), hydralazine, verapamil, diltiazem (Cartia), or medications ending in "-olol", "-artan", or "-pril")
      * diuretics (also called "water pills") such as furosemide (Lasix), bumetanide (Bumex), hydrochlorothiazide (HCTZ; Microzide), or spironolactone (Aldactone)
      * medications for enlarged prostate such as prazosin (Minipress), terazosin, doxazosin (Cardura), alfuzosin (Uroxatral), or tamsulosin (Flomax)

If persons are taking these medications and would like to participate in the study, they will be advised to discuss whether they may discontinue these medications for 48 hours before the study visit with their prescribing doctor.

Where it's running

  • University of California San Diego
    San Diego, California, United States
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.