Concentration and Attentional Deficits in POTS and Other Autonomic Neuropathies

Study Overview
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Brief Summary
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People with POTS, autoimmune autonomic neuropathy (AAN), pure autonomic failure (PAF), SFN and Ehlers Danlos Syndrome (EDS) do not only suffer from orthostatic symptoms such as dizziness, headache, neck pain, blurred vision or (pre-) syncope. They also experience deficits in attention and concentration (more precisely deficits in selective perspective, operating speed, executive functions and memory performance) mainly in upright position. Only few studies concerning cognitive impairment in autonomic neuropathies, their frequency, aetiology and therapy exist. Many patients concerned, especially with POTS, report attention deficits and brain fog with problems in their everyday life and work, predominantly in upright posture. Specific symptomatic or medical therapies do not exist. Medical treatment with Modafinil is discussed and part of a current study at Vanderbilt Autonomic Dysfunction Centre (1-5). The investigators want to investigate if problems of concentration, attention and/or cognitive dysfunction exist in people with POTS, AAN, SFN and EDS compared to healthy controls (HC). Thus the investigators use detailed clinical, autonomic and neuropsychological tests in different body positions (lying, sitting and standing) as also acute therapy (leg crossing).

Detailed Description
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We are still recruting healthy controls and patients with autoimmune autonomic neuropathy in order to perform titl table examination and laboratory testing on day one, ono an empty stomach, without morning medication. Cognitive testing is performed on day two after randomization in three groups: lying, standing and standing with legs crossed.

Official Title
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Understanding Impaired Concentration, Attentional Deficits and Their Pathophysiology in Postural Orthostatic Tachycardia Syndrome (POTS) and Other Autonomic Neuropathies (POTSKog-Study Aachen)

Conditions
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Autonomic Failure, Dysautonomia, Cognitive Impairment, Ehlers-Danlos Syndrome, Postural Tachycardia Syndrome, Pure Autonomic Failure

Intervention / Treatment
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* Procedure: leg crossing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: AAN, SFN, hEDS, POTS or healthy control diagnosis in our clinic on the basis of anamnesis, clinical data as neurological examination, tilt table, QST, skin biopsy, norepinephrine values, vitamine B12, antibodies Exclusion Criteria: for all participants pregnancy, nonage,severe heart insufficiency, deep brain Stimulation, pace maker, drug consumption, large fibre polyneuropathy for controls medication influencing blood pressure, psychiatric disease, synkopes or dizziness, neurological disorders esp. polyneuropathy, dementia, vitamine or iron deficiency

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: lying<br>cognitive tests are performed during lying in all groups (SFN, AAN, EDS, POTS and controls) | |
| No Intervention: standing<br>cognitive tests are performed during active Standing in all groups (SFN, AAN, EDS, POTS and controls) | |
| Experimental: crossed legs<br>cognitive tests are performed during leg crossing in all groups (SFN, AAN, EDS, POTS and controls) | Procedure: leg crossing<br>* As Counter maneuvre legs will be crossed and cognitive tests will be performed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| cognitive function: Stroop, TMT A und B | Change of results of cognitive function tests lying compared to standing and leg crossing | during intervention (Leg crossing) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood pressure Change (mmHg) | Change between blood pressure lying compared to compared to standing and leg crossing | during intervention (Leg crossing) | 
| Heart frequency Change (B/min) | Change between heart frequency lying compared to compared to standing and leg crossing | during intervention (Leg crossing) | 
| cerebral blood flow velocity | Change between cerebral blood flow compared to compared to standing and leg crossing | during intervention (Leg crossing) |