The Effect of Water Carbonation on Orthostatic Tolerance

Обзор

The primary purpose of this investigation is to determine whether water carbonation can improve orthostatic tolerance in healthy control volunteers. Orthostatic tolerance refers to the ability to maintain an adequate blood pressure when standing. In some individuals blood pressure can fall when standing, predisposing to dizzy spells or fainting episodes. Drinking water can boost blood pressure and making fainting episodes less likely. However, it is not clear whether the carbonation of the water has any further impact on the blood pressure response. This is important because it may be that carbonated water expands the stomach (gastric distension), provoking an increase in sympathetic activity. The increase in sympathetic nervous system activity boosts blood pressure. Resolving this question would have important implications for patients with syncope. This study will test whether carbonated water will have any further impact on blood pressure than the already known effect of non-carbonated water.

Подробное описание

The primary purpose of this investigation is to determine whether water carbonation can improve orthostatic tolerance in healthy control volunteers. Orthostatic tolerance refers to the ability to maintain an adequate blood pressure when standing \[1\]. In some individuals blood pressure can fall when standing, predisposing to dizzy spells or fainting episodes \[1\]. Drinking water can boost blood pressure and making fainting episodes less likely \[2-8\]. However, it is not clear whether the carbonation of the water has any further impact on the blood pressure response \[9,10\]. This is important because it may be that carbonated water expands the stomach (gastric distension), provoking an increase in sympathetic activity. The increase in sympathetic nervous system activity boosts blood pressure. Resolving this question would have important implications for patients with syncope. This study will test whether carbonated water will have any further impact on blood pressure than the already known effect of non-carbonated water.

Volunteers (n=25) will be asked to undergo a "tilt test" to assess cardiovascular reflex control and orthostatic tolerance (measured as time to presyncope, or near fainting, in minutes). It has been previously shown that this technique to be reproducible, reliable, and to have high sensitivity and specificity for differentiating persons with differing orthostatic tolerance, or for examining the effects of interventions aimed at improving orthostatic tolerance \[4,6,11-18\].

Volunteers will undergo this test on three separate days. On each day participants will be asked to drink a glass of water: either a 50ml drink of room temperature water (control condition), a 500ml drink of flat (non-carbonated) room temperature water, or a 500ml drink of carbonated room temperature water. The study will be conducted in a randomised, single-blind fashion. The investigator responsible for terminating the test will be blinded as to the water condition on each test day, rendering the study single blind. It will not be possible to blind participants as to the carbonation of the water, however, participants will not be informed as to the hypothesised impact of the water conditions.

Вмешательства

• Другое 500mL carbonated water
  Drink 500mL carbonated water immediately prior to head-up tilt test
• Другое 500mL still water
  Drink 500mL still water immediately prior to head-up tilt test
• Другое 50mL still water
  Drink 50mL still water immediately prior to head-up tilt test

Первичные конечные точки

• Orthostatic tolerance [Срок оценки: 0-50 minutes]

Критерии участия

Критерии включения

• healthy, English-speaking

Критерии исключения

• pregnancy or suspected pregnancy, history of cardiovascular disease, history of neurological disease, history of recurrent fainting (≥ 2 episodes of fainting with loss of consciousness in the prior 6 months)

Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.

Здоровые добровольцы: Да

Дизайн исследования

Распределение

Рандомизированное

Модель

Перекрёстный дизайн

Маскирование

Простое слепое

Основная цель

Лечение

Центры проведения

Канада · 1 центр

• Simon Fraser University — Burnaby

Публикации

• Hainsworth R, Claydon V E. Syncope and fainting: classification and physiological basis. In: Bannister R, Mathias CJ, eds. Autonomic failure: a textbook of clinical disorders of the autonomic nervous system. Oxford: Oxford University Press, 2006
• Mathias CJ. A 21st century water cure. Lancet. 2000 Sep 23;356(9235):1046-8. doi: 10.1016/S0140-6736(00)02723-9. PMID 11009136
• Mathias CJ, Young TM. Water drinking in the management of orthostatic intolerance due to orthostatic hypotension, vasovagal syncope and the postural tachycardia syndrome. Eur J Neurol. 2004 Sep;11(9):613-9. doi: 10.1111/j.1468-1331.2004.00840.x. PMID 15379740
• Schroeder C, Bush VE, Norcliffe LJ, Luft FC, Tank J, Jordan J, Hainsworth R. Water drinking acutely improves orthostatic tolerance in healthy subjects. Circulation. 2002 Nov 26;106(22):2806-11. doi: 10.1161/01.cir.0000038921.64575.d0. PMID 12451007
• Brown CM, Barberini L, Dulloo AG, Montani JP. Cardiovascular responses to water drinking: does osmolality play a role? Am J Physiol Regul Integr Comp Physiol. 2005 Dec;289(6):R1687-92. doi: 10.1152/ajpregu.00205.2005. Epub 2005 Jul 21. PMID 16037127
• Claydon VE, Schroeder C, Norcliffe LJ, Jordan J, Hainsworth R. Water drinking improves orthostatic tolerance in patients with posturally related syncope. Clin Sci (Lond). 2006 Mar;110(3):343-52. doi: 10.1042/CS20050279. PMID 16321141
• Lu CC, Diedrich A, Tung CS, Paranjape SY, Harris PA, Byrne DW, Jordan J, Robertson D. Water ingestion as prophylaxis against syncope. Circulation. 2003 Nov 25;108(21):2660-5. doi: 10.1161/01.CIR.0000101966.24899.CB. Epub 2003 Nov 17. PMID 14623807
• Boschmann M, Steiniger J, Hille U, Tank J, Adams F, Sharma AM, Klaus S, Luft FC, Jordan J. Water-induced thermogenesis. J Clin Endocrinol Metab. 2003 Dec;88(12):6015-9. doi: 10.1210/jc.2003-030780. PMID 14671205

Идентификаторы

NCT: NCT05621460 · 30000955

Первоисточники (государственные реестры)

• ClinicalTrials.gov (NIH, США)

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