Alterations of Attention in Patients With Postural Tachycardia Syndrome and Healthy Controls Depending on Body Position and Hydration
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- Numerical variables reaction time and/or hits resp. misses in the subtests "alertness" from the automated test battery "Test of Attentional Performance, mobility version"
研究概览
简要总结
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)
详细描述
Background
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 diagnosis requests a HR increment of at least 40 beats/min. The increment in HR when moving to an upright posture is often caused by a reduction in venous return because of excessive blood pooling in the lower limbs. Clinical symptoms present in POTS vary greatly. Typical symptoms are palpitations, lightheadedness, dizziness, blurred vision, mental clouding ("brain fog") or cognitive dysfunction . Additional symptoms consist of postural headaches, nausea, but also non-orthostatic symptoms such as 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 make simple daily activities difficult. Typically symptoms exacerbate in the mornings, after physical activity, after eating and during menstruation. The onset of the syndrome is associated with a variety of possible causes, e.g. a recent viral illness or autonomic neuropathy.
As mentioned above, some of the most frequent reported symptoms are concentration- and attentional problems so called "brain fog" or "mental clouding". Previous research indicates an actual deficit in cognitive functioning, which is, same as other POTS symptoms, exclusive to the upright position. However, there is no overall accepted and recognized definition of what "brain fog" is or what components it consists of. The majority of studies examined, amongst other things, aspects of attention and working memory. Ross et al. compared it to mental fatigue and showed that 67% of all POTS patients experience this symptom on a daily basis, which indicates that routine daily activities and consequent quality of life are reduced even further.
Conservative therapy in POTS consists in a high intake of water (2-3L) and salt on a daily basis, wearing compression stockings and regular endurance training. Severely affected patients may profit from additional drug treatment. A previous research group of the investigators' unit showed in 2010 the improvement of OI in POTS after acute water and clear soup intake.
Objective:
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •For patients:
- •Informed consent
- •Patients with diagnosed POTS (for criteria, see above)
- •Age: ≥18 years and ≤ 60 years
- •For healthy volunteers:
- •Informed consent
- •Age: ≥18 years and ≤ 60 years
排除标准
- •For patients:
- •Pregnancy and Breastfeeding
- •Due to clinical reasons the current medication for POTS can not be discontinued
- •For healthy volunteers:
- •Pregnancy and Breastfeeding
- •Intake of vasoactive medication or known, non-treated arterial hypertension
- •Known vasovagal syncope in medical history
结局指标
主要结局
Numerical variables reaction time and/or hits resp. misses in the subtests "alertness" from the automated test battery "Test of Attentional Performance, mobility version"
时间窗: 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"
时间窗: 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"
时间窗: 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
次要结局
- Blood pressure(After change body position and 5dl of water, up to 30 minutes)
- Brain perfusion measured with NIRS(After change body position and 5dl of water, up to 30 minutes)
- Diameter of the optic nerve(After change body position and 5dl of water, up to 30 minutes)
- Heart rate(After change body position and 5dl of water, up to 30 minutes)
- Pupil diameter(After change body position and 5dl of water, up to 30 minutes)