CAlgary SAlt for Postural Orthostatic Tachycardia Syndrome Study
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 50
- 试验地点
- 2
- 主要终点
- Upright Heart Rate
研究概览
简要总结
Many patients with postural orthostatic tachycardia syndrome (POTS) have decreased plasma volume. Current POTS guidelines recommend ~10 g of salt and 2-3 L of fluid per day. Despite this recommendation, there is no long term data evaluating the use of salt in POTS. This randomized, placebo-controlled cross-over trial will evaluate a high salt diet, compared to a normal salt diet over a period of 3 months. Participants will complete 3 in lab evaluations including autonomic function testing, tilt table testing, blood volume and urine sodium evaluation, plasma catecholamine measurements and and cytokine measurements.
详细描述
Background and Rationale:
Postural Orthostatic Tachycardia Syndrome (POTS) is a form of autonomic cardiovascular disease, primarily in women, that is often disabling. The investigators and others have found that many patients with postural tachycardia have decreased plasma volume. Current POTS guidelines recommend ~10 g of salt and 2-3 L of fluid per day. In a proof of concept dietary salt study, the investigators recently showed 6 days of a high salt diet (300 mEq/d), compared to a low salt diet, increases plasma volume, reduced standing plasma norepinephrine, and reduced HR. The high salt diet reduced the median orthostatic tachycardia by 14 bpm. Currently there is only evidence showing the benefits of supplemental salt-intake over one week. It is unknown whether the increased blood volume from high dietary salt intake will persist over several weeks, or if an "escape mechanism" will reduce blood volumes back to baseline levels. This longer-term clinical trial of high dietary salt and water will address this "escape mechanism" and ongoing dietary compliance in POTS.
Research Question & Objectives:
Primary Hypothesis: The primary hypothesis is that after 6 weeks of a moderate dietary salt plus additional salt diet, the upright HR will be lower than after 6 weeks on a moderate dietary salt alone diet.
Secondary hypotheses: The secondary hypotheses include:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
盲法说明
Study participants and investigators will be blinded throughout the duration of the study.
入排标准
- 年龄范围
- 18 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Physician Diagnosis of POTS as defined by the CCS Consensus Statement and as follows:
- •Sustained, excessive orthostatic tachycardia ≥ 30 bpm within 10 minutes standing.
- •Absence of orthostatic hypotension (>20/10 mmHg decrease) within 3 minutes standing.
- •Chronic orthostatic symptoms that improve with recumbence.
- •Age 18-60 years old.
- •Ability to attend the Calgary Autonomic Research Clinic in Calgary.
- •Resident of Canada
排除标准
- •Overt cause for postural tachycardia (i.e., acute dehydration, thyroid disease)
- •Participants with somatization or severe anxiety symptoms will be excluded
- •Pregnant (self-reported)
- •Underlying causes of tachycardia including acute hypovolemia, endocrinopathy, anemia, anxiety, medication effects, recreational drug effects, and prolonged bedrest.
- •Other factors which in the investigator's opinion would prevent the participant from completing the protocol, including poor compliance during previous studies
- •Fludrocortisone use (due to effects on renal Na+ handling)
- •Patients who have received IV saline in the 2 months preceding the study or who plan to receive it during the course of the study
结局指标
主要结局
Upright Heart Rate
时间窗: 10 Minutes
Upright heart rate measured during the tilt table test at the end of the moderate dietary salt plus additional salt arm compared to the tilt table test at the end of the moderate dietary salt alone arm
次要结局
- Vanderbilt Orthostatic Symptom Score (VOSS)(10 Minutes)
- Systolic Blood Pressure(10 Minutes)
- Diastolic Blood Pressure(10 minutes)
- Stroke volume(10 minutes)