Alterations of Attention in POTS Depending on Body Position and Hydration
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|ClinicalTrials.gov Identifier: NCT03253120|
Recruitment Status : Recruiting
First Posted : August 17, 2017
Last Update Posted : April 22, 2021
The Postural Tachycardia-Syndrome (POTS) is a form of autonomic dysregulation, typically accompanied by symptoms of orthostatic intolerance (OI). OI is defined by the inability to tolerate the upright position and is improved by lying down. POTS is considered a syndrome that may include a number of several disorders. Symptoms should be persistent for at least 6 months to reach a diagnosis. It is characterized by a sustained heart rate (HR) increment of 30 beats/min or more within 10 min of standing or head-up tilt (HUT) in adults, in the absence of orthostatic hypotension and with the presence of symptoms of OI. In children and adolescents a diagnosis requests a HR increment of at least 40 beats/min. The increment in HR when moving to an upright posture is often a response to a reduction in venous return, causing excessive blood pooling in the lower limbs. The symptoms present in POTS vary greatly. Typical symptoms are lightheadedness, dizziness, blurred vision, mental clouding ("brain fog") or cognitive dysfunction. Other symptoms may present as palpitations or chest pain. Additional symptoms consist of postural headaches, nausea, sleep disturbances, fatigue and gastrointestinal dysfunction. The manifestation of symptoms in POTS varies in severity, frequency and combination, resulting in POTS being a very heterogenous and subjective disorder. Symptoms can be severe and often make simple daily activities difficult to an extent that compromises the patients quality of life. Typically symptoms exacerbate in the mornings, after physical activity, after eating and during menstruation.
This study objective is to examine the occurrence, mechanisms and causes of impaired attention in POTS as well as to test the effect of acute water ingestion for attention in POTS. The investigators therefore conduct a study including patients with POTS and healthy volunteers.
All participants will receive a dossier of five self-assessment questionnaires after giving informed consent. Clinical examination includes 2 HUT-tests while standing for 15 minutes, conventional measuring of blood pressure, continuous recording of NIRS signals during testing, determination of pupil size, the diameter of the optic nerve and Neuropsychological testing (Test of Attentional Performance, mobility version" (TAP-M), Go/NoGo Test, Divided Attention Test)
|Condition or disease||Intervention/treatment||Phase|
|Postural Tachycardia Syndrome||Other: Water||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||30 participants|
|Intervention Model:||Parallel Assignment|
|Intervention Model Description:||Patients will drink 5dl of water. Healthy volunteers will drink 5dl of water.|
|Masking:||None (Open Label)|
|Official Title:||Alterations of Attention in Patients With Postural Tachycardia Syndrome and Healthy Controls Depending on Body Position and Hydration|
|Actual Study Start Date :||September 11, 2017|
|Estimated Primary Completion Date :||October 31, 2021|
|Estimated Study Completion Date :||March 31, 2022|
Patients will drink 5dl of water.
Patient/ Healthy volunteer will drink 5dl of Water
Healthy volunteers will drink 5dl of water.
Patient/ Healthy volunteer will drink 5dl of Water
- Numerical variables reaction time and/or hits resp. misses in the subtests "alertness" from the automated test battery "Test of Attentional Performance, mobility version" [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]"Alertness" is designed to assess tonic alertness, which is defined as the ability to maintain a high level of responsiveness in anticipation of a test stimulus. The alertness test measures the simple reaction time in response to a visual stimulus (a cross presented on the monitor)
- Numerical variables reaction time and/or hits resp. misses in the subtest "Go/NoGo" from the automated test battery "Test of Attentional Performance, mobility version" [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]The "Go/NoGo" task for assessing the specific ability of subjects to suppress undesired responses. Reaction times and errors are recorded in a simple test with two stimuli
- Numerical variables reaction time and/or hits resp. misses in the subtest "divided attention" from the automated test battery "Test of Attentional Performance, mobility version" [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]In the Test of Attentional Performance a visual and an auditory task must be processed in parallel
- Diameter of the optic nerve [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]The diameter of the optic nerve is measured with a 7-15 MHz linear array transducer in transorbital B-mode ultrasound .
- Brain perfusion measured with NIRS [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]All parameters of brain perfusion will be assessed using NIRS.
- Heart rate [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]For autonomic function testing, beat-to-beat BP and HR are measured with the Finometer device.
- Blood pressure [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]For autonomic function testing, beat-to-beat BP and HR are measured with the Finometer device.
- Pupil diameter [ Time Frame: After change body position and 5dl of water, up to 30 minutes ]Determination of pupil size will be performed with a rubber cup covering the measured eye and the operator's hand covering the nonmeasured eye. A brief 2- to 3-second pause allows the pupil to dilate briefly at which time the measurement will be taken. Pupil size is the average diameter for the entire measurement time, which is typically 3 to 4 seconds.
- Scores of the questionnaires (composite endpoint) [ Time Frame: Through study completion an average of 1 day ]Beck's Depression Inventory II (BDI-II) for assessing depression, Short Form (36) Health Survey (SF-36) for assessing health-related quality of life, Pittsburgh Sleep Quality Index (PSQI) for assessing sleep quality, International Physical Activity Questionaire
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03253120
|Contact: Werner Z'Graggen, MDemail@example.com|
|Contact: Nicole Söllfirstname.lastname@example.org|
|Principal Investigator:||Werner Z'Graggen, MD||Inselspital Bern, Department of Neurosurgery and Neurology|