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Lu F, Liu Y, Xiao Z, Wu S, Wu Q, Lin K, Yang K, Li X. Study on the effects of different postprandial positions on blood pressure and heart rate in older adults with primary hypertension and postprandial hypotension. Geriatr Nurs 2022; 46:199-205. [PMID: 35749864 DOI: 10.1016/j.gerinurse.2022.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/29/2022] [Accepted: 05/30/2022] [Indexed: 12/01/2022]
Abstract
This randomized controlled trial explored the effects of a supine position or a semi-fowler position on postprandial blood pressure (BP) of older adults with primary hypertension and postprandial hypotension (PPH). Ninety-six participants were divided into the supine group, the semi-fowler group, and the control group with block-randomization. After a meal, the patients were placed in a supine position, a 45° semi-fowler position, or allowed daily activities, respectively. BP, heart rate and PPH symptoms were measured 5 times in 120 minutes after the meal. Repeated measurement analysis showed no statistical difference in BP, heart rate and PPH symptom scores among the three groups. BP in all groups decreased rapidly at the 30-minute point, and then moved steadily downward. Taking a supine position or semi-fowler position after meals had no effect on postprandial BP and heart rate after meals in older adults with hypertension and PPH.
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Affiliation(s)
- Fengling Lu
- School of Nursing, Beijing University of Chinese Medicine, No.11 Bei San Huan Dong Lu, Chaoyang District, Beijing, 100029 China.
| | - Yu Liu
- School of Nursing, Beijing University of Chinese Medicine, No.11 Bei San Huan Dong Lu, Chaoyang District, Beijing, 100029 China.
| | - Zhu Xiao
- Department of Cardiology, China-Japan Friendship Hospital, No.2 Yinghuayuan East Street, Chaoyang District, Beijing, 100029 China.
| | - Shishi Wu
- School of Nursing, Beijing University of Chinese Medicine, No.11 Bei San Huan Dong Lu, Chaoyang District, Beijing, 100029 China.
| | - Quanying Wu
- Department of Endocrinology, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, No.1 Dongdan Dahua Road, Dongcheng District, Beijing, China.
| | - Keke Lin
- School of Nursing, Beijing University of Chinese Medicine, No.11 Bei San Huan Dong Lu, Chaoyang District, Beijing, 100029 China.
| | - Kailian Yang
- Department of Nursing, Zhaoqing Medical College, No.6 Xijiang South Road, Duanzhou District, Zhaoqing, Guangdong, 526020 China.
| | - Xiao Li
- School of Nursing, Beijing University of Chinese Medicine, No.11 Bei San Huan Dong Lu, Chaoyang District, Beijing, 100029 China.
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Parsons IT, Hockin BCD, Taha OM, Heeney ND, Williams EL, Lucci VEM, Lee RHY, Stacey MJ, Gall N, Chowienczyk P, Woods DR, Claydon VE. The effect of water temperature on orthostatic tolerance: a randomised crossover trial. Clin Auton Res 2022; 32:131-141. [PMID: 35461434 PMCID: PMC9064858 DOI: 10.1007/s10286-022-00860-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/17/2022] [Indexed: 11/04/2022]
Abstract
Purpose Bolus water drinking, at room temperature, has been shown to improve orthostatic tolerance (OT), probably via sympathetic activation; however, it is not clear whether the temperature of the water bolus modifies the effect on OT or the cardiovascular responses to orthostatic stress. The aim of this study was to assess whether differing water temperature of the water bolus would alter time to presyncope and/or cardiovascular parameters during incremental orthostatic stress. Methods Fourteen participants underwent three head-up tilt (HUT) tests with graded lower body negative pressure (LBNP) continued until presyncope. Fifteen minutes prior to each HUT, participants drank a 500 mL bolus of water which was randomised, in single-blind crossover fashion, to either room temperature water (20 °C) (ROOM), ice-cold water (0–3 °C) (COLD) or warm water (45 °C) (WARM). Cardiovascular parameters were monitored continuously. Results There was no significant difference in OT in the COLD (33 ± 3 min; p = 0.3321) and WARM (32 ± 3 min; p = 0.6764) conditions in comparison to the ROOM condition (31 ± 3 min). During the HUT tests, heart rate and cardiac output were significantly reduced (p < 0.0073), with significantly increased systolic blood pressure, stroke volume, cerebral blood flow velocity and total peripheral resistance (p < 0.0054), in the COLD compared to ROOM conditions. Conclusions In healthy controls, bolus cold water drinking results in favourable orthostatic cardiovascular responses during HUT/LBNP without significantly altering OT. Using a cold water bolus may result in additional benefits in patients with orthostatic intolerance above those conferred by bolus water at room temperature (by ameliorating orthostatic tachycardia and enhancing vascular resistance responses). Further research in patients with orthostatic intolerance is warranted.
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Madden KM, Feldman B, Meneilly GS. Baroreflex function and postprandial hypotension in older adults. Clin Auton Res 2020; 31:273-280. [PMID: 32062813 DOI: 10.1007/s10286-020-00671-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/07/2020] [Indexed: 10/25/2022]
Abstract
PURPOSE Postprandial hypotension (PPH) is a common but poorly understood etiology for fainting in older adults. One potential mechanism is age-related baroreflex dysfunction. We examined baroreflex function in older adults with PPH and without PPH (noPPH) during a standardized meal test. METHODS 57 adults (age ≥ 65; 24 PPH, 33 noPPH, mean age 77.9 ± 0.9 years, 54% female) were recruited and had meal tests performed. The baroreflex effectiveness index (BEI, %) and baroreflex sensitivity (BRS, ms/mm Hg) were calculated using the sequence method. RESULTS Baseline BEI (22 ± 2 versus 23 ± 2 percent, t = - 0.411, p = 0.682) and BRS (14.1 ± 2.4 versus 13.8 ± 2.5 ms/mm of Hg, t = - 0.084, p = 0.933) were similar in PPH and noPPH subjects. During the meal test PPH subjects showed significantly lower BEI as compared to noPPH subjects (time × PPH, F = 2.791, p = 0.042), while there was no difference in the postprandial change in BRS (time, F = 0.618, p = 0.605). CONCLUSION Patients with PPH demonstrated an acute postprandial decrease in baroreflex effectiveness during meal testing as compared with normal subjects, suggesting a potential contributing mechanism for this condition.
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Affiliation(s)
- Kenneth M Madden
- Gerontology and Diabetes Research Laboratory, Division of Geriatric Medicine, Department of Medicine, University of British Columbia, Vancouver, BC, Canada. .,Centre for Hip Health and Mobility, University of British Columbia, Vancouver, BC, Canada. .,Allan M. McGavin Chair in Geriatric Medicine, Room 7185, Gordon and Leslie Diamond Health Care Centre, 2775 Laurel St., Vancouver, BC, V5Z 1M9, Canada.
| | - Boris Feldman
- Gerontology and Diabetes Research Laboratory, Division of Geriatric Medicine, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Graydon S Meneilly
- Gerontology and Diabetes Research Laboratory, Division of Geriatric Medicine, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
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TSUCHIE H, MIYAKOSHI N, MASUTANI N, TAKAHASHI K, KOBAYASHI A, HONGO M, KASUKAWA Y, INOUE H, SHIMADA Y. Impact of spinal kyphosis on gastric myoelectrical activity in elderly patients with osteoporosis. Biomed Res 2019; 40:215-223. [DOI: 10.2220/biomedres.40.215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Hiroyuki TSUCHIE
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
| | - Naohisa MIYAKOSHI
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
| | - Norimitsu MASUTANI
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
| | - Keita TAKAHASHI
- Department of Electrical and Electronic Engineering, Akita University Graduate School of Engineering and Resource Science
| | - Akira KOBAYASHI
- Honobono-En, the Health Care Facility for the Elderly, Seiwa-Kai Medical Corporation
| | - Michio HONGO
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
| | - Yuji KASUKAWA
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
| | - Hiroshi INOUE
- Department of Electrical and Electronic Engineering, Akita University Graduate School of Engineering and Resource Science
| | - Yoichi SHIMADA
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine
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Kazadi LC, Fletcher J, Barrow PA. Gastric cooling and menthol cause an increase in cardiac parasympathetic efferent activity in healthy adult human volunteers. Exp Physiol 2018; 103:1302-1308. [PMID: 30070742 DOI: 10.1113/ep087058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/31/2018] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? How do gastric stretch and gastric cooling stimuli affect cardiac autonomic control? What is the main finding and its importance? Gastric stretch causes an increase in cardiac sympathetic activity. Stretch combined with cold stimulation result in an elimination of the sympathetic response to stretch and an increase in cardiac parasympathetic activity, in turn resulting in a reduction in heart rate. Gastric cold stimulation causes a shift in sympathovagal balance towards parasympathetic dominance. The cold-induced bradycardia has the potential to decrease cardiac workload, which might be significant in individuals with cardiovascular pathologies. ABSTRACT Gastric distension increases blood pressure and heart rate in young, healthy humans, but little is known about the effect of gastric stretch combined with cooling. We used a randomized crossover study to assess the cardiovascular responses to drinking 300 ml of ispaghula husk solution at either 6 or 37°C in nine healthy humans (age 24.08 ± 9.36 years) to establish the effect of gastric stretch with and without cooling. The effect of consuming peppermint oil capsules to activate cold thermoreceptors was also investigated. The ECG, respiratory movements and continuous blood pressure were recorded during a 5 min baseline period, followed by a 115 min post-drink period, during which 5 min epochs of data were recorded. Cardiac autonomic activity was assessed using time and frequency domain analyses of respiratory sinus arrhythmia to quantify parasympathetic autonomic activity, and corrected QT (QTc) interval analysis to quantify sympathetic autonomic activity. Gastric stretch only caused a significant reduction in QTc interval lasting up to 15 min, with a concomitant but non-significant increase in heart rate, indicating an increased sympathetic cardiac tone. The additional effect of gastric cold stimulation was significantly to reduce heart rate for up to 15 min, elevate indicators of cardiac parasympathetic tone and eliminate the reduction in QTc interval seen with gastric stretch only. Stimulation of gastric cold thermoreceptors with menthol also caused a significant reduction in heart rate and concomitant increase in the root mean square of successive differences. These findings indicate that gastric cold stimulation causes a shift in the sympathovagal balance of cardiac control towards a more parasympathetic dominant pattern.
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Affiliation(s)
- Lubobo-Claude Kazadi
- Department of Biomedical Science and Physiology, School of Sciences, Faculty of Science and Engineering, University of Wolverhampton, Wulfruna Street, Wolverhampton, UK
| | - Janine Fletcher
- Department of Biomedical Science and Physiology, School of Sciences, Faculty of Science and Engineering, University of Wolverhampton, Wulfruna Street, Wolverhampton, UK
| | - Paul A Barrow
- Department of Biomedical Science and Physiology, School of Sciences, Faculty of Science and Engineering, University of Wolverhampton, Wulfruna Street, Wolverhampton, UK
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Pham HT, Stevens JE, Rigda RS, Phillips LK, Wu T, Hausken T, Soenen S, Visvanathan R, Rayner CK, Horowitz M, Jones KL. Effects of intraduodenal administration of the artificial sweetener sucralose on blood pressure and superior mesenteric artery blood flow in healthy older subjects. Am J Clin Nutr 2018; 108:156-162. [PMID: 29878043 DOI: 10.1093/ajcn/nqy060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 03/12/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Postprandial hypotension (PPH) occurs frequently, particularly in older people and those with type 2 diabetes, and is associated with increased morbidity and mortality. The magnitude of the decrease in blood pressure (BP) induced by carbohydrate, fat, and protein appears to be comparable and results from the interaction of macronutrients with the small intestine, including an observed stimulation of mesenteric blood flow. It is not known whether artificial sweeteners, such as sucralose, which are widely used, affect BP. OBJECTIVE The aim of this study was to evaluate the effects of intraduodenal sucralose on BP and superior mesenteric artery (SMA) blood flow, compared with intraduodenal glucose and saline (control), in healthy older subjects. DESIGN Twelve healthy subjects (6 men, 6 women; aged 66-79 y) were studied on 3 separate occasions in a randomized, double-blind, crossover design. After an overnight fast, subjects had concurrent measurements of BP and heart rate (HR; automated device), SMA blood flow (Doppler ultrasound), and blood glucose (glucometer) during intraduodenal infusion of 1) glucose (25% wt:vol, ∼1400 mOsmol/L), 2) sucralose (4 mmol/L, ∼300 mOsmol/L), or 3) saline (0.9% wt:vol, ∼300 mOsmol/L) at a rate of 3 mL/min for 60 min followed by intraduodenal saline for a further 60 min. RESULTS There was a decrease in mean arterial BP (P < 0.001) during intraduodenal glucose [baseline (mean ± SEM): 91.7 ± 2.6 mm Hg compared with t = 60 min: 85.9 ± 2.8 mm Hg] but not during intraduodenal saline or intraduodenal sucralose. The HR (P < 0.0001) and SMA blood flow (P < 0.0001) also increased during intraduodenal glucose but not during intraduodenal saline or intraduodenal sucralose. As expected, blood glucose concentrations increased in response to glucose (P < 0.0001) but not saline or sucralose. CONCLUSIONS In healthy older subjects, intraduodenal administration of the artificial sweetener sucralose was not associated with changes in BP or SMA blood flow. Further studies are therefore warranted to determine the potential role for artificial sweeteners as a therapy for PPH. This trial was registered at http://www.ANZCTR.org.au as ACTRN12617001249347.
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Affiliation(s)
- Hung T Pham
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
| | - Julie E Stevens
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Rachael S Rigda
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
| | - Liza K Phillips
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
- Endocrine and Metabolic Unit
| | - Tongzhi Wu
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
| | - Trygve Hausken
- Department of Gastroenterology, Haukeland University Hospital, Bergen, Norway
| | - Stijn Soenen
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
| | - Renuka Visvanathan
- NHMRC Center of Research Excellence in Frailty, The University of Adelaide, Adelaide, South Australia, Australia
- Aged and Extended Care Services, Queen Elizabeth Hospital, Adelaide, South Australia, Australia
| | - Christopher K Rayner
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, South Australia, Australia
| | - Michael Horowitz
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
- Endocrine and Metabolic Unit
| | - Karen L Jones
- National Health and Medical Research Council (NHMRC) Centre of Research Excellence in Translating Nutritional Science to Good Health
- Endocrine and Metabolic Unit
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Tonneijck L, Muskiet MHA, Twisk JW, Kramer MHH, Danser AHJ, Joles JA, Smits MM, van Raalte DH. Lixisenatide Versus Insulin Glulisine on Fasting and Postbreakfast Systemic Hemodynamics in Type 2 Diabetes Mellitus Patients. Hypertension 2018; 72:314-322. [PMID: 29915021 DOI: 10.1161/hypertensionaha.117.10740] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/08/2018] [Accepted: 05/17/2018] [Indexed: 12/20/2022]
Abstract
The prolonged treatment effects of a short-acting GLP-1RA (glucagon-like peptide-1 receptor agonist), such as lixisenatide, on fasting and postprandial systemic hemodynamics in type 2 diabetes mellitus patients are unknown. In this secondary analysis, we included 34 overweight insulin glargine-treated type 2 diabetes mellitus patients (mean±SD age, 62±7 years; HbA1c, 8.0±0.9%; systolic blood pressure [BP], 133.9±16.1 mm Hg; diastolic BP, 75.4±8.39 mm Hg) that were randomized to once-daily lixisenatide 20 μg or once-daily titrated insulin glulisine for 8 weeks. Systemic hemodynamics (oscillometric device and finger photoplethysmography), arterial stiffness (applanation tonometry), and cardiac sympathovagal balance (heart rate variability) were measured in the fasting state and repetitively (up to minute 175) after a standardized mixed breakfast. Acetaminophen was given orally to estimate gastric emptying rate. Lixisenatide did not affect fasting systemic hemodynamics compared with insulin glulisine from baseline to week 8. Postbreakfast overall, lixisenatide compared with insulin glulisine tended to increase systolic BP by 5.2±2.9 mm Hg (P=0.087) and increased diastolic BP by 5.4±1.4 mm Hg (P<0.001), with respective maximal differences of +10.2±3.7 mm Hg (P=0.007) and +7.2±1.5 mm Hg (P<0.001). Lixisenatide increased systemic vascular resistance (P<0.001) and arterial stiffness (P=0.007). No between-group differences in overall postbreakfast heart rate, cardiac output, or cardiac sympathovagal balance, and circulating catecholamines, angiotensin II, or aldosterone were observed. Both treatments lowered HbA1c similarly, whereas lixisenatide achieved greater reductions in postbreakfast plasma glucose excursions. Lixisenatide slowed gastric emptying rate, which statistically explained changes in postbreakfast BP. Lixisenatide compared with once-daily titrated insulin glulisine for 8 weeks does not affect fasting but increases postbreakfast BP in insulin glargine-treated type 2 diabetes mellitus patients. This effect could, at least in part, be explained by reduced passage rate of nutrients and water and activation of the gastrovascular reflex.
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Affiliation(s)
- Lennart Tonneijck
- From the Department of Internal Medicine, Diabetes Center (L.T., M.H.A.M., M.H.H.K., M.M.S., D.H.v.R.)
| | - Marcel H A Muskiet
- From the Department of Internal Medicine, Diabetes Center (L.T., M.H.A.M., M.H.H.K., M.M.S., D.H.v.R.)
| | - Jos W Twisk
- Department of Epidemiology and Biostatistics (J.W.T.)
| | - Mark H H Kramer
- From the Department of Internal Medicine, Diabetes Center (L.T., M.H.A.M., M.H.H.K., M.M.S., D.H.v.R.)
| | - A H Jan Danser
- VU University Medical Center, Amsterdam, The Netherlands; Division of Pharmacology and Vascular Medicine, Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands (A.H.J.D.)
| | - Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center, Utrecht, The Netherlands (J.A.J.)
| | - Mark M Smits
- From the Department of Internal Medicine, Diabetes Center (L.T., M.H.A.M., M.H.H.K., M.M.S., D.H.v.R.)
| | - Daniël H van Raalte
- From the Department of Internal Medicine, Diabetes Center (L.T., M.H.A.M., M.H.H.K., M.M.S., D.H.v.R.)
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Trahair LG, Wu T, Feinle‐Bisset C, Marathe CS, Rayner CK, Horowitz M, Jones KL. Comparative effects of small intestinal glucose on blood pressure, heart rate, and noradrenaline responses in obese and healthy subjects. Physiol Rep 2018; 6:e13610. [PMID: 29446224 PMCID: PMC5812881 DOI: 10.14814/phy2.13610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 01/12/2018] [Indexed: 02/07/2023] Open
Abstract
Meal consumption leads to an increase in sympathetic output to compensate for hemodynamic changes and maintain blood pressure (BP). Obesity is associated with a blunting of the sympathetic response to meal ingestion, but interpretation of studies investigating these responses is compromised by their failure to account for the rate of gastric emptying, which is an important determinant of postprandial cardiovascular and sympathetic responses and, in both health and obesity, exhibits a wide interindividual variation. We sought to determine the effects of intraduodenal glucose infusion, bypassing gastric emptying, on BP, heart rate (HR), and noradrenaline responses in obese and healthy control subjects. 12 obese subjects (age 36.6 ± 3.9 years, body mass index (BMI) 36.1 ± 1.3 kg/m2 ) and 23 controls (age 27.8 ± 2.4 years, BMI 22.4 ± 0.5 kg/m2 ) received intraduodenal infusions of glucose at 1 or 3 kcal/min, or saline, for 60 min (t = 0-60 min), followed by intraduodenal saline (t = 60-120 min). BP and HR were measured with an automatic cuff, and blood samples collected for measurement of plasma noradrenaline. Intraduodenal glucose at 1 kcal/min was associated with a fall in diastolic BP in the control subjects only (P < 0.01), with no change in systolic BP, HR or noradrenaline in either group. In both groups, intraduodenal glucose at 3 kcal/min was associated with a fall in diastolic (P < 0.01), but not systolic, BP, and rises in HR (P < 0.001) and plasma noradrenaline (P < 0.01), with no difference in responses between the groups. We conclude that cardiovascular and sympathetic responses to intraduodenal glucose infusion are comparable between obese and control subjects, and dependent on the rate of glucose delivery.
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Affiliation(s)
- Laurence G. Trahair
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
| | - Tongzhi Wu
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
| | - Christine Feinle‐Bisset
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
| | - Chinmay S. Marathe
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
| | - Christopher K. Rayner
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
- Department of Gastroenterology and HepatologyRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Michael Horowitz
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
| | - Karen L. Jones
- School of MedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good HealthAdelaideSouth AustraliaAustralia
- Endocrine and Metabolic UnitRoyal Adelaide HospitalAdelaideSouth AustraliaAustralia
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Trahair LG, Rajendran S, Visvanathan R, Chapman M, Stadler D, Horowitz M, Jones KL. Comparative effects of glucose and water drinks on blood pressure and cardiac function in older subjects with and without postprandial hypotension. Physiol Rep 2017; 5:5/13/e13341. [PMID: 28684639 PMCID: PMC5506527 DOI: 10.14814/phy2.13341] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 05/30/2017] [Indexed: 02/07/2023] Open
Abstract
Postprandial hypotension (PPH) occurs frequently and is thought to reflect an inadequate increase in cardiac output to compensate for the rise in splanchnic blood flow after a meal. Gastric distension by water attenuates the postprandial fall in blood pressure (BP). Cardiac hemodynamics (stroke volume (SV), cardiac output (CO), and global longitudinal strain (GLS)) have hitherto not been measured in PPH We sought to determine the comparative effects of water and glucose drinks on cardiac hemodynamics in healthy older subjects and individuals with PPH Eight healthy older subjects (age 71.0 ± 1.7 years) and eight subjects with PPH (age 75.5 ± 1.0 years) consumed a 300 mL drink of either water or 75 g glucose (including 150 mg 13C-acetate) in randomized order. BP and heart rate (HR) were measured using an automatic device, SV, CO, and GLS by transthoracic echocardiography and gastric emptying by measurement of 13CO2 In both groups, glucose decreased systolic BP (P < 0.001) and increased HR, SV, and CO (P < 0.05 for all). The fall in systolic BP was greater (P < 0.05), and increase in HR less (P < 0.05), in the PPH group, with no difference in SV or CO Water increased systolic BP (P < 0.05) in subjects with PPH and, in both groups, decreased HR (P < 0.05) without affecting SV, CO, or GLS In subjects with PPH, the hypotensive response to glucose and the pressor response to water were related (R = -0.75, P < 0.05). These observations indicate that, in PPH, the hypotensive response to oral glucose is associated with inadequate compensatory increases in CO and HR, whereas the pressor response to water ingestion is maintained and, possibly, exaggerated.
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Affiliation(s)
- Laurence G Trahair
- Discipline of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide, Adelaide, South Australia, Australia
| | - Sharmalar Rajendran
- Discipline of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- Cardiology Unit, The Queen Elizabeth Hospital Central Adelaide Local Health Network, Woodville South, South Australia, Australia
- Cardiology Unit, Lyell McEwin Hospital Northern Local Health Network, Elizabeth Vale, South Australia, Australia
| | - Renuka Visvanathan
- Discipline of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide, Adelaide, South Australia, Australia
- Aged and Extended Care Services, The Queen Elizabeth Hospital Central Adelaide Local Health Network, Woodville South, South Australia, Australia
- Adelaide Geriatrics Training and Research with Aged Care (G-TRAC) Centre School of Medicine The University of Adelaide, Adelaide, South Australia, Australia
| | - Matthew Chapman
- Cardiology Unit, The Queen Elizabeth Hospital Central Adelaide Local Health Network, Woodville South, South Australia, Australia
| | - Daniel Stadler
- Cardiology Unit, The Queen Elizabeth Hospital Central Adelaide Local Health Network, Woodville South, South Australia, Australia
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide, Adelaide, South Australia, Australia
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- NHMRC Centre of Research Excellence in Translating Nutritional Science to Good Health The University of Adelaide, Adelaide, South Australia, Australia
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Nguyen TAN, Abdelhamid YA, Phillips LK, Chapple LS, Horowitz M, Jones KL, Deane AM. Nutrient stimulation of mesenteric blood flow - implications for older critically ill patients. World J Crit Care Med 2017; 6:28-36. [PMID: 28224105 PMCID: PMC5295167 DOI: 10.5492/wjccm.v6.i1.28] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 12/16/2016] [Accepted: 01/02/2017] [Indexed: 02/06/2023] Open
Abstract
Nutrient ingestion induces a substantial increase in mesenteric blood flow. In older persons (aged ≥ 65 years), particularly those with chronic medical conditions, the cardiovascular compensatory response may be inadequate to maintain systemic blood pressure during mesenteric blood pooling, leading to postprandial hypotension. In older ambulatory persons, postprandial hypotension is an important pathophysiological condition associated with an increased propensity for syncope, falls, coronary vascular events, stroke and death. In older critically ill patients, the administration of enteral nutrition acutely increases mesenteric blood flow, but whether this pathophysiological response is protective, or precipitates mesenteric ischaemia, is unknown. There are an increasing number of older patients surviving admission to intensive care units, who are likely to be at increased risk of postprandial hypotension, both during, and after, their stay in hospital. In this review, we describe the prevalence, impact and mechanisms of postprandial hypotension in older people and provide an overview of the impact of postprandial hypotension on feeding prescriptions in older critically ill patients. Finally, we provide evidence that postprandial hypotension is likely to be an unrecognised problem in older survivors of critical illness and discuss potential options for management.
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Endo MY, Fujihara C, Miura A, Kashima H, Fukuba Y. Effects of meal ingestion on blood pressure and regional hemodynamic responses after exercise. J Appl Physiol (1985) 2016; 120:1343-8. [DOI: 10.1152/japplphysiol.00842.2015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/22/2016] [Indexed: 11/22/2022] Open
Abstract
This study investigated the combined effects of consuming a meal during postexercise hypotension (PEH) on hemodynamics. Nine healthy young male subjects performed each of three trials in random order: 1) cycling at 50% of heart rate reserve for 60 min, 2) oral ingestion of a carbohydrate liquid meal (75 g glucose), or 3) carbohydrate ingestion at 40 min after cycling exercise. Blood pressure, heart rate, cardiac output, and blood flow in the superior mesenteric (SMA), brachial, and popliteal arteries were measured continuously before and after each trial. Regional vascular conductance (VC) was calculated as blood flow/mean arterial pressure. Blood pressure decreased relative to baseline values ( P < 0.05) after exercise cessation. Blood flow and VC in the calf and arm increased after exercise, whereas blood flow and VC in the SMA did not. Blood pressure did not change after meal ingestion; however, blood flow and VC significantly decreased in the brachial and popliteal arteries and increased in the SMA for 120 min after the meal ( P < 0.05). When the meal was ingested during PEH, blood pressure decreased below PEH levels and remained decreased for 40 min before returning to postexercise levels. The sustained increase in blood flow and VC in the limbs after exercise was reduced to baseline resting levels immediately after the meal, postprandial cardiac output was unchanged by the increased blood flow in the SMA, and total VC and SMA VC increased. Healthy young subjects can suppress severe hypotension by vasoconstriction of the limbs even when carbohydrate is ingested during PEH.
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Affiliation(s)
- Masako Yamaoka Endo
- Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Chizuko Fujihara
- Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Akira Miura
- Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Hideaki Kashima
- Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Yoshiyuki Fukuba
- Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
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Rocha TC, Ramos PDS, Ricardo DR. INGESTÃO DE ÁGUA NO SISTEMA NERVOSO AUTÔNOMO: UMA REVISÃO SISTEMÁTICA E META-ANÁLISE. REV BRAS MED ESPORTE 2016. [DOI: 10.1590/1517-869220162201154165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO Verificar, por meio de uma revisão sistemática, o efeito da ingestão de água (IA) no sistema nervoso autônomo (SNA) e variáveis hemodinâmicas em indivíduos adultos. Foram analisados estudos publicados entre 2000 e 2015, tendo como referência a base de dados Medline via Pubmed, sendo utilizado na construção da frase de pesquisa o MeSH. Foram estabelecidos os seguintes critérios de inclusão: ensaios clínicos controlados e randomizados (ECCR) realizados em humanos, na língua inglesa. Como critério de exclusão: intervenções pouco claras, mal descritas ou inadequadas e na forma de resumos. Utilizou-se as seguintes variáveis para a seleção dos estudos: frequência cardíaca (FC), pressão arterial (PA), componente de alta frequência (AF) e resistência vascular periférica (RVP). Foi usada a sistematização PRISMA para a elaboração desta revisão e a realização de uma meta-análise com o objetivo de evidenciar matematicamente os resultados da frequência cardíaca após a ingestão de água em sete estudos que avaliaram esta variável. Fizeram parte desta revisão 10 ECCR envolvendo 246 indivíduos com idade entre 19 a 64 anos, sendo que 34,55% do sexo masculino. A maioria dos ECCR analisados apresentou alterações após a IA. As alterações comumente observadas foram: diminuição da FC (estatisticamente significativa p < 0,001), aumento da AF e RVP. Contudo, em relação à PA, os resultados demonstraram-se conflitantes, com estudos que evidenciaram aumento e outros que não observaram diferença significativa. Esta revisão evidencia os efeitos da IA no SNA, em especial na FC, AF e RVP, não obstante em relação às alterações hemodinâmicas expressas pela PA permanece ainda um óbice em relação à comunidade científica.
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Prevalence of and risk factors for postprandial hypotension in older Chinese men. JOURNAL OF GERIATRIC CARDIOLOGY : JGC 2016; 12:600-4. [PMID: 26788035 PMCID: PMC4712364 DOI: 10.11909/j.issn.1671-5411.2015.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Objective To assess the prevalence of and risk factors for postprandial hypotension (PPH) among old and very old Chinese men. Methods The study included 349 Chinese men aged 65 and older, grouped into two age categories: group 1 (old) included 163 men aged 65 to 80 years; group 2 (very old) included 186 men aged over 80 years. Blood pressure changes after meals were assessed every 15 min by ambulatory blood pressure monitoring. Symptoms after meal ingestion and after standing up and changes in the baseline condition relative to blood pressure changes were observed continuously. Additional baseline data included body mass index, medical history, and medication use. Results The prevalence of PPH was 59.3% overall and was significantly higher in group 2 than group 1 (63.4% vs. 54.6%, P < 0.05). In group 2, the prevalence of PPH after breakfast (33.8%) and lunch (32.1%) were higher than that after supper (20.9%), P < 0.05. Hypertension and age were significant risk factors for PPH (OR = 2.188, 95% CI: 1.134−4.223, P = 0.02; OR = 1.86, 95% CI: 1.112−3.11, P = 0.018, respectively). In contrast, acarbose use was protective against PPH (OR = 0.4, 95% CI: 0.189−0.847, P = 0.017). The decrease in blood pressure during PPH was 20−40 mmHg and the maximum was 90 mmHg. PPH usually occurred at 30−60 min after a meal and lasted 30−120 min. Conclusions These findings demonstrate that the prevalence of PPH in men aged over 80 years is significantly higher than those in men aged 65 to 80 years, and the blood pressure decline is also higher for men aged over 80 years. In addition, hypertension and age were main risk factors for PPH in the older men, which suggest that preventing and treating PPH is worthwhile.
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Thazhath SS, Wu T, Bound MJ, Checklin HL, Jones KL, Willoughby S, Horowitz M, Rayner CK. Changes in meal composition and duration affect postprandial endothelial function in healthy humans. Am J Physiol Gastrointest Liver Physiol 2014; 307:G1191-7. [PMID: 25342049 DOI: 10.1152/ajpgi.00323.2014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Endothelial function, measured by flow-mediated dilatation (FMD), predicts cardiovascular events and is impaired postprandially. The objective of this study was to evaluate the effects of changes in composition or duration of ingestion of a meal, which slows gastric emptying and/or small intestinal nutrient exposure, on postprandial endothelial function. Twelve healthy subjects (6 male, 6 female; 33 ± 6 yr) were each studied on three occasions, in a randomized crossover design. After an overnight fast, subjects consumed a [(13)C]octanoic acid-labeled mashed potato meal ("meal 1"), or meal 1 mixed with 9 g guar ("meal 2") within 10 min, or meal 1 divided into 12 equal portions over 60 min ("meal 3"). Brachial artery FMD was measured every 30 min for 120 min. Blood glucose, serum insulin, and gastric emptying (breath test) were evaluated for 240 min. Data are means ± SE. Compared with meal 1, meal 2 was associated with slower gastric emptying (half-emptying time 285 ± 27 vs. 208 ± 15 min, P < 0.05), lower postprandial blood glucose and insulin (P < 0.001 for both), and a delayed, but more sustained, suppression of FMD (P < 0.001). After meal 3, both glycemic increment and reduction in FMD were less than after meal 2 (P < 0.05 for both). The decrement in FMD was directly related to the increment in blood glucose (r = 0.46, P = 0.02). We conclude that, in health, postprandial FMD is influenced by perturbation of gastric emptying and the duration of meal consumption, which also impact on glycemia.
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Affiliation(s)
- Sony S Thazhath
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Tongzhi Wu
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Michelle J Bound
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Helen L Checklin
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Karen L Jones
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Scott Willoughby
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre for Heart Rhythm Disorders, The University of Adelaide and Royal Adelaide Hospital, Adelaide, Australia
| | - Michael Horowitz
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
| | - Christopher K Rayner
- Discipline of Medicine, The University of Adelaide, Royal Adelaide Hospital, Adelaide, Australia; Centre of Research Excellence in Translating Nutritional Science to Good Health, The University of Adelaide, Adelaide, Australia; and
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McMullen MK, Whitehouse JM, Whitton PA, Towell A. Bitter tastants alter gastric-phase postprandial haemodynamics. JOURNAL OF ETHNOPHARMACOLOGY 2014; 154:719-727. [PMID: 24802704 DOI: 10.1016/j.jep.2014.04.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 04/20/2014] [Accepted: 04/27/2014] [Indexed: 06/03/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Since Greco-Roman times bitter tastants have been used in Europe to treat digestive disorders, yet no pharmacological mechanism has been identified which can account for this practice. This study investigates whether the bitter tastants, gentian root (Gentian lutea L.) and wormwood herb (Artemisia absinthium L.), stimulate cephalic and/or gut receptors to alter postprandial haemodynamics during the gastric-phase of digestion. MATERIALS AND METHODS Normal participants ingested (1) 100 mL water plus capsules containing either cellulose (placebo-control) or 1000 mg of each tastant (n=14); or (2) 100mL of water flavoured with 500 or 1500 mg of each tastant (a) gentian (n=12) and (b) wormwood (n=12). A single beat-to-beat cardiovascular recording was obtained for the entire session. Pre/post-ingestion contrasts with the control were analysed for (1) the encapsulated tastants, in the "10 to 15" minute post-ingestion period, and (2) the flavoured water in the "5 to 10" minute post-ingestion period. RESULTS Water, the placebo-control, increased cardiac contraction force and blood pressure notwithstanding heart rate decreases. Encapsulated tastants did not further alter postprandial haemodynamics. In contrast gentian (500 and 1500 mg) and wormwood (1500 mg) flavoured water elicited increased peripheral vascular resistance and decreased cardiac output, primarily by reducing stroke volume rather than heart rate. CONCLUSIONS Drinking 100mL water elicits a pressor effect during the gastric-phase of digestion due to increased cardiac contraction force. The addition of bitter tastants to water elicits an additional and parallel pressor effect due to increased peripheral vascular resistance; yet the extent of the post-prandial blood pressure increases are unchanged, presumably due to baroreflex buffering. The vascular response elicited by bitter tastants can be categorised as a sympathetically-mediated cephalic-phase response. A possible mechanism by which bitter tastants could positively influence digestion is altering gastric-phase postprandial haemodynamics and supporting postprandial hyperaemia.
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Affiliation(s)
- Michael K McMullen
- Division of Complementary Medicine, University of Westminster, London, UK.
| | - Julie M Whitehouse
- Division of Complementary Medicine, University of Westminster, London, UK
| | | | - Anthony Towell
- Department of Psychology, University of Westminster, Westminster, UK
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The effect of percutaneous renal denervation on muscle sympathetic nerve activity in hypertensive patients. Int J Cardiol 2014; 176:8-12. [PMID: 25027168 DOI: 10.1016/j.ijcard.2014.06.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 05/27/2014] [Accepted: 06/20/2014] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The rationale of percutaneous renal denervation (RDN) is based on extensive studies suggesting that renal nerves contribute to hypertension and that they comprise a sensible treatment target. Muscle sympathetic nerve activity (MSNA) is considered to be one of the few reliable methods to quantify central sympathetic activity. The aim of this current study is to determine the effect of RDN on MSNA in a standardized fashion. METHODS MSNA was determined in 13 patients before and 6months after RDN. Anti-hypertensive medication was stopped before MSNA. If cessation of medication was considered unsafe, a patient was instructed to use the exact same medication on both occasions. RESULTS Ten sets of MSNA recordings were of good quality for analysis. Mean age was 57 ± 3 years and mean eGFR was 85 ± 18 mL/min/1.73 m(2). MSNA was determined twice during a medication free interval in 5 patients; 1 patient used the exact same medication twice, and 4 patients used different drugs. Mean BP changed from 206 ± 7 over 116 ± 4 mmHg, to 186 ± 6 over 106 ± 3 mmHg, 6 months after RDN (p=0.06 for systolic BP, p=0.04 for diastolic BP). Mean resting heart rate did not change (p=0.44). MSNA did not change after RDN: 37 ± 4 bursts/min and 43 ± 4 bursts/min (p=0.11) at baseline and after RDN, respectively. In the 6 patients with standardized medication use during the MSNA sessions, results were comparable. CONCLUSIONS Treatment with RDN did not result in a change in MSNA. Changes in BP did not correlate with changes in MSNA.
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Trahair LG, Horowitz M, Jones KL. Postprandial hypotension: a systematic review. J Am Med Dir Assoc 2014; 15:394-409. [PMID: 24630686 DOI: 10.1016/j.jamda.2014.01.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 02/07/2023]
Abstract
BACKGROUND Postprandial hypotension (PPH) is an important clinical problem, which has received inappropriately little attention. METHODS A systematic search of the databases PubMed, Embase, Cochrane Library, and Web of Knowledge, from their inception to the present time, was conducted to identify studies relevant to the epidemiology, pathophysiology, and/or management of PPH. RESULTS A total of 417 full-text papers were retrieved from database searching and, following screening, 248 were retained. Of these, 167 papers were considered eligible for inclusion. CONCLUSIONS PPH occurs commonly in older people and represents a major cause of morbidity. Although the pathophysiology of PPH remains poorly defined, diverse factors, including impairments in sympathetic and baroreflex function, release of vasodilatory peptides, the rate of small intestinal nutrient delivery, gastric distension, and splanchnic blood pooling, appear important. Current pharmacologic and nonpharmacologic management is suboptimal. Research into the pathophysiology of PPH represents a priority so that management can be targeted more effectively.
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Affiliation(s)
- Laurence G Trahair
- Discipline of Medicine, University of Adelaide, Adelaide, Australia; NHMRC Center of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, Australia
| | - Michael Horowitz
- Discipline of Medicine, University of Adelaide, Adelaide, Australia; NHMRC Center of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, Australia
| | - Karen L Jones
- Discipline of Medicine, University of Adelaide, Adelaide, Australia; NHMRC Center of Research Excellence in Translating Nutritional Science to Good Health, University of Adelaide, Adelaide, Australia.
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Nakata-Fukuda M, Hirata T, Keto Y, Yamano M, Yokoyama T, Uchiyama Y. Inhibitory effect of the selective serotonin 5-HT₃ receptor antagonist ramosetron on duodenal acidification-induced gastric hypersensitivity in rats. Eur J Pharmacol 2014; 731:88-92. [PMID: 24632457 DOI: 10.1016/j.ejphar.2014.02.040] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 02/19/2014] [Accepted: 02/28/2014] [Indexed: 12/20/2022]
Abstract
Irritable bowel syndrome (IBS) and functional dyspepsia (FD) are both functional gastrointestinal disorders and frequently co-occur in patients. While one cause of FD appears to be gastric hypersensitivity, whether the hypersensitivity is affected by IBS treatments remains unclear, given the lack of appropriate animal models for testing. Here, we established an experimental model of duodenal acidification-induced gastric hypersensitivity in conscious rats. The model involved duodenal acidification induced by the infusion of hydrochloric acid into the proximal duodenum, with the nociceptive response being determined as the change in mean arterial pressure (MAP) during gastric distension via an indwelling latex balloon. Using our model we evaluated the effects of duodenal acidification, increased distension pressure, and orally administered therapeutic agents for IBS with diarrhea (IBS-D). Duodenal acidification enhanced the pressor response during gastric distension, and pretreatment with the opioid κ-receptor agonist fedotozine (10mg/kg, intra-arterial) inhibited the pressor response. Pressure levels of 15-60 mm Hg increased MAP in response to gastric distension. The serotonin 5-HT3 receptor antagonist ramosetron (30 μg/kg) inhibited MAP increase induced by duodenal acidification, with no other IBS-D therapeutic agents showing any effect. In contrast, the serotonin 5-HT3 receptor agonist m-chlorophenylbiguanide (1mg/kg) significantly enhanced the pressor response during gastric distension. These findings indicate that the serotonin 5-HT3 receptor plays a key role in duodenal acidification-induced gastric hypersensitivity in rats, suggesting that ramosetron may reduce FD symptoms by ameliorating sensitized gastric perception.
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Affiliation(s)
- Mari Nakata-Fukuda
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan; Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
| | - Takuya Hirata
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan
| | - Yoshihiro Keto
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan
| | - Mayumi Yamano
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan
| | - Toshihide Yokoyama
- Pharmacology Research Labs., Drug Discovery Research, Astellas Pharma Inc., 21 Miyukigaoka, Tsukuba, Ibaraki 305-8585, Japan
| | - Yasuo Uchiyama
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
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Mochel JP, Fink M, Peyrou M, Desevaux C, Deurinck M, Giraudel JM, Danhof M. Chronobiology of the renin-angiotensin-aldosterone system in dogs: relation to blood pressure and renal physiology. Chronobiol Int 2013; 30:1144-59. [DOI: 10.3109/07420528.2013.807275] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Taubel J, Wong AH, Naseem A, Ferber G, Camm AJ. Shortening of the QT Interval After Food Can Be Used to Demonstrate Assay Sensitivity in Thorough QT Studies. J Clin Pharmacol 2013; 52:1558-65. [DOI: 10.1177/0091270011419851] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Kocełak P, Żak-Gołąb A, Rzemieniuk A, Smętek J, Sordyl R, Tyrka A, Sosnowski M, Zahorska-Markiewicz B, Chudek J, Olszanecka-Glinianowicz M. The influence of oral water load on energy expenditure and sympatho-vagal balance in obese and normal weight women. Arch Med Sci 2012; 8:1003-8. [PMID: 23319974 PMCID: PMC3542490 DOI: 10.5114/aoms.2012.32406] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 11/26/2011] [Accepted: 12/16/2011] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Oral water load may increase the energy expenditure (EE) by stimulation of sympathetic dependent thermogenesis. Thus, drinking of water may be helpful in weight reduction. The aim of the study is to assess the influence of water load on energy expenditure and sympathetic activity in obese and normal weight women. MATERIAL AND METHODS Forty-five women were included. Energy expenditure was measured twice, in the morning and after oral water load, by the indirect calorimetric method. The heart rate variability parameters low frequency (LF), high frequency (HF), LF/HF index, standard deviation of normal RR intervals (SDNN) and root mean square difference among successive RR normal intervals (rMSSD) were used for the indirect assessment of the sympatho-vagal balance. RESULTS Resting energy expenditure (REE) was significantly higher in obese than in normal weight women (1529 ±396 kcal/day vs. 1198 ±373 kcal/day; p = 0.02). In both study groups after water load EE increased significantly (by 20% and by 12%, corresponding to 8.6 kcal/h and 5.2 kcal/h respectively), while, LF/HF index increased simultaneously. The increase of energy expenditure (EE) did not exceed the energetic cost of water heating, from room to body temperature - 15 kcal/1000 ml. There was no correlation between changes of energy expenditure (EE) and heart rate variability (HRV) parameters. CONCLUSIONS The increase of EE induced by water load is mostly related to the heating of the consumed water to body temperature. The assessment of autonomic balance by means of standard HRV indices had been found insufficient for detection of actually operating mechanisms.
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Affiliation(s)
- Piotr Kocełak
- Health Promotion and Obesity Management Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Agnieszka Żak-Gołąb
- Pathophysiology Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Anna Rzemieniuk
- Student Scientific Association, Health Promotion and Obesity Management Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Joanna Smętek
- Student Scientific Association, Health Promotion and Obesity Management Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Ryszard Sordyl
- Student Scientific Association, Health Promotion and Obesity Management Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Agata Tyrka
- Student Scientific Association, Health Promotion and Obesity Management Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
| | - Maciej Sosnowski
- 3 Division of Cardiology, Medical University of Silesia, Unit of Noninvasive Cardiovascular Diagnostics, Upper-Silesian Medical Centre, Katowice, Poland
| | | | - Jerzy Chudek
- Pathophysiology Unit, Department of Pathophysiology, Medical University of Silesia, Katowice, Poland
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Vanis L, Gentilcore D, Lange K, Gilja OH, Rigda RS, Trahair LG, Feinle-Bisset C, Rayner CK, Horowitz M, Jones KL. Effects of variations in intragastric volume on blood pressure and splanchnic blood flow during intraduodenal glucose infusion in healthy older subjects. Am J Physiol Regul Integr Comp Physiol 2012; 302:R391-9. [PMID: 22129616 DOI: 10.1152/ajpregu.00464.2011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The postprandial reduction in blood pressure (BP) is triggered by the interaction of nutrients with the small intestine and associated with an increase in splanchnic blood flow. Gastric distension may attenuate the postprandial fall in BP. The aim of this study was to determine the effects of differences in intragastric volume, including distension at a low (100 ml) volume, on BP and superior mesenteric artery (SMA) blood flow responses to intraduodenal glucose in healthy older subjects. BP and heart rate (HR; automated device), SMA blood flow (Doppler ultrasound), mesenteric vascular resistance (MVR), and plasma norepinephrine of nine male subjects (65-75 yr old) were measured after an overnight fast on 4 separate days in random order. On each day, subjects were intubated with a nasoduodenal catheter, incorporating a duodenal infusion port, and orally with a second catheter, incorporating a barostat bag, positioned in the fundus. Each subject received a 60-min (t = 0-60 min) intraduodenal glucose infusion (3 kcal/min) and gastric distension at a volume of 1) 0 ml (V0), 2) 100 ml (V100), 3) 300 ml (V300), or 4) 500 ml (V500). Systolic BP fell (P < 0.05) during V0, but not during V100, V300, or V500. In contrast, HR (P < 0.01) and SMA blood flow (P < 0.001) increased and MVR decreased (P < 0.05) comparably on all 4 days. Plasma norepinephrine rose (P < 0.01) in response to intraduodenal glucose, with no difference between the four treatments. There was a relationship between the areas under the curve for the change in systolic BP from baseline with intragastric volume (r = 0.60, P < 0.001). In conclusion, low-volume (≤100 ml) gastric distension has the capacity to abolish the fall in BP induced by intraduodenal glucose in healthy older subjects without affecting SMA blood flow or MVR. These observations support the concept that nonnutrient gastric distension prior to a meal has potential therapeutic applications in the management of postprandial hypotension.
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Affiliation(s)
- Lora Vanis
- Univ. of Adelaide Discipline of Medicine, Royal Adelaide Hospital, North Terrace, Adelaide, Australia
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Tsuchie H, Fukata C, Takahashi K, Miyakoshi N, Kobayashi A, Kasukawa Y, Shimada Y, Inoue H. Impact of lumbar kyphosis on gastric myoelectrical activity and heart rate variability in a model using flexion posture in healthy young adults. ACTA ACUST UNITED AC 2012; 32:271-8. [PMID: 21878734 DOI: 10.2220/biomedres.32.271] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Relationship between lumbar kyphotic deformity and gastroesophageal reflux disease has been indicated in recent years. But it remains unclear whether kyphotic deformity of the lumbar vertebrae affects gastric motility. Healthy young adults (n = 20) were analyzed by recording the electrogastrography (EGG) and heart rate variability (HRV) before and after meal with flexion and neutral postures. Dominant power (DP) and dominant frequency (DF) of EGG and low frequency (LF) and high frequency (HF) of HRV were analyzed in blocks of 10 minutes' duration. In neutral posture, DPs of all postprandial durations were significantly higher than those during fasting in two channels (P < 0.05, P < 0.01). However, in flexion posture, only DP at postprandial 20 (10-20 minutes after eating) in a channel was significantly higher than that during fasting (P < 0.05). DF in neutral posture was significantly higher than that in flexion posture at postprandial 20 in a channel (P < 0.05). The standard deviation of DF at postprandial 10 in flexion posture was significantly higher than that during fasting in a channel (P < 0.05). LF/HF in neural posture was significantly higher than that in flexion posture at postprandial 10 (P < 0.05). These findings suggest that inhibition of stomach myoelectrical activity was induced in the flexion posture in this lumbar kyphotic model, and autonomic activity as assessed by HRV did not accord with that expected from EGG.
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Affiliation(s)
- Hiroyuki Tsuchie
- Department of Orthopedic Surgery, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
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Riganello F, Garbarino S, Sannita WG. Heart Rate Variability, Homeostasis, and Brain Function. J PSYCHOPHYSIOL 2012. [DOI: 10.1027/0269-8803/a000080] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Measures of heart rate variability (HRV) are major indices of the sympathovagal balance in cardiovascular research. These measures are thought to reflect complex patterns of brain activation as well and HRV is now emerging as a descriptor thought to provide information on the nervous system organization of homeostatic responses in accordance with the situational requirements. Current models of integration equate HRV to the affective states as parallel outputs of the central autonomic network, with HRV reflecting its organization of affective, physiological, “cognitive,” and behavioral elements into a homeostatic response. Clinical application is in the study of patients with psychiatric disorders, traumatic brain injury, impaired emotion-specific processing, personality, and communication disorders. HRV responses to highly emotional sensory inputs have been identified in subjects in vegetative state and in healthy or brain injured subjects processing complex sensory stimuli. In this respect, HRV measurements can provide additional information on the brain functional setup in the severely brain damaged and would provide researchers with a suitable approach in the absence of conscious behavior or whenever complex experimental conditions and data collection are impracticable, as it is the case, for example, in intensive care units.
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Affiliation(s)
- Francesco Riganello
- S. Anna Institute and RAN – Research in Advanced Neurorehabilitation, Crotone, Italy
| | - Sergio Garbarino
- Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Italy
| | - Walter G. Sannita
- Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Italy
- Department of Psychiatry, State University of New York, Stony Brook, NY, USA
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Hlebowicz J, Lindstedt S, Björgell O, Dencker M. The effect of endogenously released glucose, insulin, glucagon-like peptide 1, ghrelin on cardiac output, heart rate, stroke volume, and blood pressure. Cardiovasc Ultrasound 2011; 9:43. [PMID: 22206473 PMCID: PMC3280936 DOI: 10.1186/1476-7120-9-43] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 12/29/2011] [Indexed: 11/24/2022] Open
Abstract
Background Ingestion of a meal increases the blood flow to the gastrointestinal organs and affects the heart rate (HR), blood pressure and cardiac output (CO), although the mechanisms are not known. The aim of this study was to evaluate the effect of endogenously released glucose, insulin, glucagon-like peptide 1 (GLP-1), ghrelin on CO, HR, stroke volume (SV), and blood pressure. Methods Eleven healthy men and twelve healthy women ((mean ± SEM) aged: 26 ± 0.2 y; body mass index: 21.8 ± 0.1 kg/m2)) were included in this study. The CO, HR, SV, systolic and diastolic blood pressure, antral area, gastric emptying rate, and glucose, insulin, GLP-1 and ghrelin levels were measured. Results The CO and SV at 30 min were significantly higher, and the diastolic blood pressure was significantly lower, than the fasting in both men and women (P < 0.05). In men, significant correlations were found between GLP-1 level at 30 min and SV at 30 min (P = 0.015, r = 0.946), and between ghrelin levels and HR (P = 0.013, r = 0.951) at 110 min. Significant correlations were also found between the change in glucose level at 30 min and the change in systolic blood pressure (P = 0.021, r = -0.681), and the change in SV (P = 0.008, r = -0.748) relative to the fasting in men. The insulin 0-30 min AUC was significantly correlated to the CO 0-30 min AUC (P = 0.002, r = 0.814) in men. Significant correlations were also found between the 0-120 min ghrelin and HR AUCs (P = 0.007, r = 0.966) in men. No statistically significant correlations were seen in women. Conclusions Physiological changes in the levels of glucose, insulin, GLP-1 and ghrelin may influence the activity of the heart and the blood pressure. There may also be gender-related differences in the haemodynamic responses to postprandial changes in hormone levels. The results of this study show that subjects should not eat immediately prior to, or during, the evaluation of cardiovascular interventions as postprandial affects may affect the results, leading to erroneous interpretation of the cardiovascular effects of the primary intervention. Trial registration number NCT01027507
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Affiliation(s)
- Joanna Hlebowicz
- Center for Emergency, Department of Cardiology, Skåne University Hospital, Malmö, Lund University, Sweden.
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Min DK, Tuor UI, Chelikani PK. Gastric distention induced functional magnetic resonance signal changes in the rodent brain. Neuroscience 2011; 179:151-8. [PMID: 21284950 DOI: 10.1016/j.neuroscience.2011.01.051] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 01/14/2011] [Accepted: 01/23/2011] [Indexed: 12/29/2022]
Abstract
Investigating the localization of gastric sensation within the brain is important for understanding the neural correlates of satiety. Previous rodent studies have identified the brain-stem and hypothalamus as key mediators of gastric distention-induced satiation. Although, recent blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) studies in humans have identified a role for higher cortico-limbic structures in mediating the satiation effects of gastric distention, the role of these regions in rodents remains to be characterized. We determined the effects of gastric distention on global spatio-temporal BOLD fMRI signal changes in the rodent brain. Brain images were acquired with a high resolution 9.4 T magnet during gastric distention with continuous monitoring of blood pressure in adult male Sprague Dawley rats (n=8-10). Distention of the stomach with an intragastric balloon, at rates which mimicked the rate of consumption and emptying of a mixed nutrient liquid meal, resulted in robust reduction in food intake and increase in blood pressure. Gastric distention increased BOLD fMRI activity within homeostatic regions such as the hypothalamus and nucleus tractus solitarius, as well as non homeostatic regions including the hippocampus, amygdala, thalamus, cerebellum and the cortex (cingulate, insular, motor and sensory cortices). Further, the increase in BOLD fMRI activity following distention was strongly correlated to an increase in blood pressure. These results indicate that gastric distention, mimicking the rate of intake and emptying of a liquid meal, increases BOLD fMRI activity in both homeostatic and non homeostatic brain circuits which regulate food intake, and that these BOLD fMRI signal changes may in part be attributable to transient increases in blood pressure.
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Affiliation(s)
- D K Min
- Gastrointestinal Research Group, Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
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Van Orshoven NP, Jansen PAF, Oudejans I, Schoon Y, Oey PL. Postprandial hypotension in clinical geriatric patients and healthy elderly: prevalence related to patient selection and diagnostic criteria. J Aging Res 2010; 2010:243752. [PMID: 21152196 PMCID: PMC2989753 DOI: 10.4061/2010/243752] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 08/05/2010] [Accepted: 08/23/2010] [Indexed: 11/20/2022] Open
Abstract
The aims of this study were to find out whether Postprandial hypotension (PPH) occurs more frequently in patients admitted to a geriatric ward than in healthy elderly individuals, what the optimal interval between blood pressure measurements is in order to diagnose PPH and how often it is associated with symptoms.The result of this study indicates that PPH is present in a high number of frail elderly, but also in a few healthy older persons. Measuring blood pressure at least every 10 minutes for 60 minutes after breakfast will adequately diagnose PPH, defined as >20 mmHg systolic fall, in most patients. However with definition of PPH as >30 mmHg systolic fall, measuring blood pressure every 10 minutes will miss PPH in one of three patients. With the latter definition of PPH the presence of postprandial complaints is not associated with the existence of PPH.
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Affiliation(s)
- Narender P Van Orshoven
- Department of Neurology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands
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Vanis L, Gentilcore D, Hausken T, Pilichiewicz AN, Lange K, Rayner CK, Feinle-Bisset C, Meyer JH, Horowitz M, Jones KL. Effects of gastric distension on blood pressure and superior mesenteric artery blood flow responses to intraduodenal glucose in healthy older subjects. Am J Physiol Regul Integr Comp Physiol 2010; 299:R960-7. [PMID: 20554933 DOI: 10.1152/ajpregu.00235.2010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Postprandial hypotension occurs frequently and is associated with increased morbidity. Gastric distension may attenuate the postprandial fall in blood pressure (BP). Using a barostat, we sought to determine the effects of gastric distension on BP, heart rate (HR), and superior mesenteric artery (SMA) blood flow responses to intraduodenal glucose in eight (6 men, 2 women) healthy older (65-75 yr old) subjects. BP and HR were measured using an automated device and SMA blood flow was measured using Doppler ultrasound on 4 days in random order. SMA blood flow was calculated using the radius of the SMA and time-averaged mean velocity. Subjects were intubated with a nasoduodenal catheter incorporating a duodenal infusion port. On 2 of the 4 days, they were intubated orally with a second catheter, incorporating a barostat bag, positioned in the fundus and set at 8 mmHg above minimal distending pressure. Each subject received a 60-min (0-60 min) intraduodenal infusion of glucose (3 kcal/min) or saline (0.9%); therefore, the four study conditions were as follows: intraduodenal glucose + barostat (glucose + distension), intraduodenal saline + barostat (saline + distension), intraduodenal glucose (glucose), and intraduodenal saline (saline). Systolic and diastolic BP fell during glucose compared with saline (P = 0.05 and P = 0.003, respectively) and glucose + distension (P = 0.01 and P = 0.05, respectively) and increased during saline + distension compared with saline (P = 0.04 and P = 0.006, respectively). The maximum changes in systolic BP were -14 +/- 5, +11 +/- 2, -3 +/- 4, and +15 +/- 3 mmHg for glucose, saline, glucose + distension, and saline + distension, respectively. There was an increase in HR during glucose and glucose + distension (maximum rise = 14 +/- 2 and 14 +/- 3 beats/min, respectively), but not during saline or saline + distension. SMA blood flow increased during glucose and glucose + distension (2,388 +/- 365 and 1,673 +/- 187 ml/min, respectively), but not during saline, and tended to decrease during saline + distension (821 +/- 115 and 864 +/- 116 ml/min, respectively). In conclusion, gastric distension has the capacity to abolish the fall in BP and attenuate the rise in SMA blood flow induced by intraduodenal glucose in healthy older subjects.
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Affiliation(s)
- Lora Vanis
- University of Adelaide, Discipline of Medicine, Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000, Australia
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Gentilcore D, Nair NS, Vanis L, Rayner CK, Meyer JH, Hausken T, Horowitz M, Jones KL. Comparative effects of oral and intraduodenal glucose on blood pressure, heart rate, and splanchnic blood flow in healthy older subjects. Am J Physiol Regul Integr Comp Physiol 2009; 297:R716-22. [PMID: 19553500 DOI: 10.1152/ajpregu.00215.2009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Postprandial hypotension occurs frequently, particularly in the elderly. The magnitude of the fall in blood pressure (BP) and rise in heart rate (HR) in response to enteral glucose are greater when gastric emptying (GE) or small intestinal infusion are more rapid. Meal ingestion is associated with an increase in splanchnic blood flow. In contrast, gastric distension may attenuate the postprandial fall in BP. The aims of this study were to evaluate, in older subjects, the comparative effects of intraduodenal glucose infusion, at a rate similar to GE of oral glucose, on BP, HR, superior mesenteric artery (SMA) flow, and blood glucose. Eight healthy subjects (5 men, 3 women, age 66-75 yr) were studied on two occasions. On day 1, each subject ingested 300 ml of water containing 75 g glucose. GE was quantified by three-dimensional ultrasonography between time t = 0-120 min, and the rate of emptying (kcal/min) was calculated. On day 2, glucose was infused intraduodenally at the same rate as that on day 1. On both days, BP, HR, SMA flow, and blood glucose were measured. The mean GE of oral glucose was 1.3 +/- 0.1 kcal/min. Systolic BP (P < 0.01), SMA flow (P < 0.05), and blood glucose (P < 0.01) were greater and HR less (P < 0.01) after oral, compared with intraduodenal, glucose. There were comparable falls in diastolic BP during the study days (P < 0.01 for both). We conclude that the magnitude of the fall in systolic BP and rise in HR are less after oral, compared with intraduodenal, glucose, presumably reflecting the "protective" effect of gastric distension.
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Affiliation(s)
- Diana Gentilcore
- Univ. of Adelaide, Discipline of Medicine, Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000, Australia
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30
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Uchino M, Ito K, Kuwahara M, Ebukuro S, Tsubone H. Interactions of carotid sinus or aortic input with emetic signals from gastric afferents and vestibular system. Auton Neurosci 2008; 144:36-42. [DOI: 10.1016/j.autneu.2008.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2008] [Revised: 08/07/2008] [Accepted: 09/12/2008] [Indexed: 02/06/2023]
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Gentilcore D, Meyer JH, Rayner CK, Horowitz M, Jones KL. Gastric distension attenuates the hypotensive effect of intraduodenal glucose in healthy older subjects. Am J Physiol Regul Integr Comp Physiol 2008; 295:R472-7. [PMID: 18495838 DOI: 10.1152/ajpregu.00108.2008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Postprandial hypotension occurs frequently, and current management is suboptimal. Recent studies suggest that the magnitude of the fall in postprandial blood pressure (BP) may be attenuated by gastric distension. The aim of this study was to determine the effect of gastric distension on the hypotensive response to intraduodenal (ID) glucose. Eight healthy subjects (5 males, 3 females, aged 65-76 years) received an ID infusion of either 1) 50 g glucose in 300 ml saline (ID glucose) over 60 min (t=0-60 min), 2) 50 g glucose in 300 ml saline over 60 min and intragastric (4) infusion of 500 ml water between t=7-10 min (IG water and ID glucose), or 3) ID saline (0.9%) infusion over 60 min and IG infusion of 500 ml water (IG water and ID saline) all followed by ID saline infusion for another 60 min (t=60-120 min) on three separate days. BP and heart rate (HR) were measured. Gastric emptying (GE) of the IG water was quantified by two-dimensional ultrasonography. Between t=0-60 min, systolic and diastolic BP was greater (P<0.05 for both) with IG water and ID saline compared with IG water and ID glucose, and less (P<0.05 for both) with ID glucose compared with IG water and ID glucose. These effects were evident at relatively low IG volumes (approximately 300 ml). GE was faster with IG water and ID saline when compared with IG water and ID glucose. We conclude that, in healthy older subjects, IG administration of water markedly attenuates the hypotensive response to ID glucose, presumably as a result of gastric distension.
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Affiliation(s)
- Diana Gentilcore
- University of Adelaide, Discipline of Medicine, Royal Adelaide Hospital, North Terrace, Adelaide, SA, 5000, Australia
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32
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van Baak MA. Meal-induced activation of the sympathetic nervous system and its cardiovascular and thermogenic effects in man. Physiol Behav 2008; 94:178-86. [DOI: 10.1016/j.physbeh.2007.12.020] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 12/20/2007] [Accepted: 12/21/2007] [Indexed: 12/01/2022]
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Cantù P, Savojardo D, Barelli MV, Buonamici V, Bertinieri G, Penagini R. Cardiovascular effects of gastric intubation and distension in healthy humans. Neurogastroenterol Motil 2008; 20:304-10. [PMID: 18004986 DOI: 10.1111/j.1365-2982.2007.01032.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Few data exist on the effect of upper gut stimuli on the cardiovascular system. Aim of our study was to evaluate the cardiovascular effects of gastric intubation and distension. Eleven healthy subjects (eight men, aged 21-30 years) were studied and a non-invasive beat-to-beat cardiovascular monitoring system was used. After 15-min basal recording, a bag catheter was positioned in the proximal stomach and connected to a barostat. Recordings were first performed for 15 min with the bag deflated, then during inflation of air using a 100 mL per 2 min stepwise protocol until epigastric discomfort was reported, and finally for 15 min with the bag inflated at 75% of discomfort volume spared from the preceding period by 10 min with the bag deflated. Presence of the deflated bag catheter significantly increased mean arterial pressure. Stepwise distension progressively increased heart rate and cardiac index, while mean arterial pressure was affected only at discomfort volume. Peripheral resistances and systemic plasma catecholamines were unaffected. During prolonged distension, the effect on heart rate and cardiac index was transient. In conclusion, both gastric intubation and distension alter cardiovascular parameters, but the effect of distension undergoes rapid adaptation. Experimentally induced gastric distension is a valuable stimulus to study viscero-cardiovascular reflexes and their mechanisms using beat-to-beat measurements.
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Affiliation(s)
- P Cantù
- Cattedra di Gastroenterologia, Dipartimento di Scienze Mediche, University of Milan, Milan, Italy
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van Orshoven NP, van Schelven LJ, Akkermans LMA, Jansen PAF, Horowitz M, Feinle-Bisset C, van Huffelen AC, Oey PL. The effect of intraduodenal glucose on muscle sympathetic nerve activity in healthy young and older subjects. Clin Auton Res 2008; 18:28-35. [PMID: 18236004 DOI: 10.1007/s10286-008-0452-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Accepted: 11/19/2007] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The cardiovascular response to a meal is modulated by gastric distension and the interaction of nutrients, particularly carbohydrate, within the small intestine. We tested the hypothesis that the depressor effect of small intestinal glucose is greater in older than in young subjects, because the reflex increase in muscle sympathetic nerve activity (MSNA) is blunted by age. METHODS The effects of intraduodenal glucose infusion (IDGI) on blood pressure, heart rate and MSNA were evaluated in eight healthy young subjects (4 women; mean age +/- SEM: 28.8 +/- 3.4 years), eight healthy elderly (4 women; 75.3 +/- 1.6 years) and in two patients with symptomatic postprandial hypotension (PPH), one young (21 years), and one old (90 years). RESULTS In both young and elderly healthy subjects, IDGI decreased blood pressure (P < 0.05), but the fall in systolic blood pressure was greater in the older subjects (-17.0 +/- 4.1 vs. -6.5 +/- 1.6 mmHg, P < 0.03). MSNA increased similarly, after infusion in both young (9.0 +/- 3.4 bursts/min) and elderly (7.8 +/- 1.0 bursts/min) subjects. Baroreflex sensitivity for number of sympathetic bursts was attenuated in the elderly (P < 0.03). The increase in burst area in the young patient with PPH was attenuated (18 vs. 63% in the healthy young group). INTERPRETATION The fall in BP induced by IDGI was greater in healthy elderly compared to healthy young subjects. The reason for this is unclear, as they have similar increases in MSNA.
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Affiliation(s)
- Narender P van Orshoven
- Department of Clinical Neurophysiology, Rudolf Magnus Institute of Neuroscience, Utrecht, The Netherlands
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Vianna LC, Oliveira RB, Silva BM, Ricardo DR, Araújo CGS. Water intake accelerates post-exercise cardiac vagal reactivation in humans. Eur J Appl Physiol 2007; 102:283-8. [PMID: 17929050 DOI: 10.1007/s00421-007-0584-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2007] [Indexed: 11/28/2022]
Abstract
Post-exercise cardiac vagal reactivation is well-investigated; however, the effect of water intake during this period has not been well studied. Therefore, our aim was to assess the influence of water intake on the cardiac vagal reactivation after 30 min of a submaximal cycling exercise. Ten healthy subjects (eight men) aged 23-35 years were evaluated. A 3-day testing cycle duration, subjects were randomly chosen to drink either 500 ml (experimental visit) or 50 ml (control visit) of water immediately after the 30-min cycling exercise at a workload representing 80% of a previously measured anaerobic threshold. A cardiac vagal index (CVI) was obtained using the 4-s exercise test measured before and after (10 and 30 min) exercise at each testing day. Data analysis (2 x 3 ANOVA for repeated measures) showed higher cardiac vagal activity at the 30-min post-exercise period when 500 ml of water was ingested. CVI values for the 500 and 50 ml trials were 1.55 +/- 0.04 vs. 1.49 +/- 0.04, P = 0.003 (mean +/- SEM), respectively. Heart rate and blood pressure values were relatively the same. In conclusion, water intake of about 500 ml immediately after 30 min of cycling exercise accelerates post-exercise cardiac vagal reactivation. These results suggest that post-exercise hydration might be beneficial not only for thermoregulation, but also for vagal reactivation.
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Affiliation(s)
- Lauro C Vianna
- Programa de Pós-Graduação em Educação Física da Universidade Gama Filho, Rio de Janeiro, RJ, Brazil
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Newman B, Tommolino E, Andreozzi C, Joychan S, Pocedic J, Heringhausen J. The effect of a 473-mL (16-oz) water drink on vasovagal donor reaction rates in high-school students. Transfusion 2007; 47:1524-33. [PMID: 17655598 DOI: 10.1111/j.1537-2995.2007.01293.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Recent clinical studies found that a water drink prevented orthostatic hypotension in healthy subjects subjected to a tilt-table test. A water drink was tested as a method to decrease vasovagal donor reactions in high-school students. STUDY DESIGN AND METHODS A total of 8894 high-school donations in Fall 2004 and 2005 were assigned to groups receiving or not receiving a 473-mL water drink after acceptance for whole-blood donation. In addition, 4340 donations in 2004 were reduced to 2895 donations ("balanced 2004 group") with an algorithm that equally balanced the donors between the water and no water arms. RESULTS The donor reaction rate was 9.9 percent (349 reactions/3534 donations) in donors given a water drink versus 12.5 percent (668 reactions/5360 donations; p = 0.0002) in donors not given a water drink. Donors given a water drink had a 21 percent reduction in their donor reaction rate. The main benefit of water was in Caucasian, first-time donors. In the balanced 2004 group, the donor reaction rate was 10.6 percent (153 reactions/1438 donations) in donors given a water drink versus 14.8 percent (216 reactions/1457 donations; p = 0.0008) in donors not given a water drink. Donors given a water drink in the balanced 2004 group had a 28 percent reduction in their donor reaction rate. The use of water did not interfere with donor processing and was judged by collection staff as easy to implement. CONCLUSION A 473-mL water drink decreased the vasovagal donor reaction rate in high-school donors by 21 percent, but to varying degrees in different subpopulations.
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Affiliation(s)
- Bruce Newman
- American Red Cross Blood Services, Southeastern Michigan Region, 100 Mack Avenue, Detroit, MI 48201, USA.
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Catz A, Bluvshtein V, Pinhas I, Akselrod S, Gelernter I, Nissel T, Vered Y, Bornstein NM, Korczyn AD. Hemodynamic effects of liquid food ingestion in mid-thoracic paraplegia: is supine postprandial hypotension related to thoracic spinal cord damage? Spinal Cord 2006; 45:96-103. [PMID: 16850007 DOI: 10.1038/sj.sc.3101939] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Postprandial hypotension (PPH) appears in various conditions with autonomic failure and was symptomatic in a patient with thoracic paraplegia, but was not remarkable in patients with tetraplegia. OBJECTIVE To determine whether the pathology causing PPH may include a thoracic but not a cervical spinal cord lesion (SCL). DESIGN An experimental controlled study. SETTING The spinal research laboratory, Loewenstein Hospital, Raanana, Israel. SUBJECTS Thirteen healthy subjects, 10 patients with traumatic T(4)-T(6) paraplegia, and 11 patients with traumatic C(4)-C(7) tetraplegia. MAIN OUTCOME MEASURES Heart rate (HR), blood pressure (BP), HR and BP spectral components (LF, HF, LF/HF), cerebral blood flow velocity (CBFV), and cerebrovascular resistance index (CVRi). METHODS The effects of a standard liquid meal on the outcome measures were compared between the three subject groups monitored for HR, BP, and CBFV, from 55 min before to 45 min after the start of the meal. The recorded signals were digitized online and analyzed off-line in the time and frequency domains. RESULTS After meal, BP decreased only in the paraplegia group (P<0.01), HR increased more prominently in this group (P<0.01), CVRi tended to decrease only in the paraplegia group, CBFV did not change significantly in any group, and HR LF/HF increased (P<0.001) in all groups but tended to increase more in paraplegia. CONCLUSIONS Patients with mid-thoracic SCL may develop PPH. The pathology causing PPH can include a thoracic but not a cervical SCL. The normal hemodynamic reaction to liquid meal ingestion is mediated through the mid-thoracic spinal cord. The sympathovagal balance increases after food ingestion, more prominently in patients with PPH, and cerebrovascular resistance changes during PPH may help maintain the cerebral circulation.
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Affiliation(s)
- A Catz
- Department IV, Spinal Rehabilitation, Loewenstein Rehabilitation Hospital, 278 Achuza Street, Raanana 43100, Israel
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van Orshoven NP, Andriesse GI, van Schelven LJ, Smout AJ, Akkermans LMA, Oey PL. Subtle involvement of the parasympathetic nervous system in patients with irritable bowel syndrome. Clin Auton Res 2006; 16:33-9. [PMID: 16477493 DOI: 10.1007/s10286-006-0307-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Accepted: 06/18/2005] [Indexed: 12/23/2022]
Abstract
This study comprises assessment of autonomic function in irritable bowel syndrome (IBS) patients, focusing on meal-related changes. In 18 IBS patients (4 males, mean age 45+/-3.0 [SEM] years) and 19 healthy volunteers (6 males, mean age 41+/-3.5 years) blood pressure, heart rate, heart rate variability and muscle sympathetic nerve activity (MSNA) were assessed before, during and after consumption of a standardized meal. In pre- and postprandial phase Valsalva maneuver, cold pressor test (CPT) and deep breathing test were carried out and Visual Analog Scale (VAS) scores for nausea, bloating and pain were obtained. In the IBS group, the meal induced significantly higher VAS scores for pain (P=0.002) and bloating (P=0.02). During food intake, the increase in blood pressure, heart rate and MSNA was equal in patients and controls, but the increase of LF/HF ratio of heart rate variability was significantly higher in the IBS group (median [quartiles] 2.29 [1.14-3.00] versus 0.77 [0.25-1.81]; P=0.03). IBS patients scored lower on pre- and postprandial RRmax/RRmin ratio during deep breathing (DB ratio, P=0.03). The increase in MSNA (burst frequency) in response to CPT tended to be higher in the IBS patients (P=0.07). We conclude that reactivity to food intake, measured as muscle sympathetic nerve activity, is normal in IBS patients. The lower DB ratio and higher LF/HF ratio during food intake in IBS patients is an indication of a reduced parasympathetic reactivity. These results suggest that reduced baseline activity as well as responsiveness of the parasympathetic system could play a role in the pathogenesis of IBS.
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Affiliation(s)
- Narender P van Orshoven
- Rudolf Magnus Institute of Neuroscience, Dept. of Clinical Neurophysiology, University Medical Centre Utrecht, 3508 GA Utrecht, The Netherlands
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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; 110:343-52. [PMID: 16321141 DOI: 10.1042/cs20050279] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Water drinking improves OT (orthostatic tolerance) in healthy volunteers; however, responses to water in patients with PRS (posturally related syncope) are unknown. Therefore the aim of the present study was to examine whether water would improve OT in patients with PRS. In a randomized controlled cross-over fashion, nine patients with PRS ingested 500 ml and 50 ml (control) of water 15 min before tilting on two separate days. OT was determined using a combined test of head-up tilting and lower body suction and expressed as the time required to induce presyncope. We measured blood pressure and heart rate (using Portapres) and middle cerebral artery velocity (using transcranial Doppler). SV (stroke volume) and TPR (total peripheral resistance) were calculated using the Modelflow method. OT was significantly (P<0.02) greater after drinking 500 ml of water than after 50 ml (25.4+/-1.5 compared with 19.8+/-2.3 min respectively). After ingestion of 500 ml of water, blood pressure during tilting was higher, the tiltinduced reduction in SV was smaller and the increase in TPR was greater (all P<0.05). The correlation coefficient of the relationship between cerebral blood flow velocity and pressure was lower after 500 ml of water (0.43+/-0.1 compared with 0.73+/-0.1; P<0.05), indicating better autoregulation. In conclusion, drinking 500 ml of water increased OT and improved cardiovascular and cerebrovascular control during orthostasis. Patients with PRS should be encouraged to drink water before situations likely to precipitate a syncopal attack.
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Affiliation(s)
- Victoria E Claydon
- Institute for Cardiovascular Research, University of Leeds, Leeds LS2 9JT, UK.
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Gentilcore D, Doran S, Meyer JH, Horowitz M, Jones KL. Effects of intraduodenal glucose concentration on blood pressure and heart rate in healthy older subjects. Dig Dis Sci 2006; 51:652-6. [PMID: 16614984 DOI: 10.1007/s10620-006-3187-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2005] [Accepted: 07/12/2005] [Indexed: 02/07/2023]
Abstract
The aims of this study were to determine whether the hypotensive and heart rate responses to small intestinal glucose infusion are dependent on the glucose concentration. Eight healthy subjects, aged 65-78 years, were studied on 3 separate days in random order. Each subject received intraduodenal infusions of 50 g of glucose in either 300 mL (16.7%), 600 mL (8.3%), or 1200 mL (4.1%) of saline (0.9%) at a rate of 3 kcal/min for 60 minutes (t = 0-60 minutes), followed by saline (0.9%) for a further 60 minutes (t = 60-120 minutes). During the infusions, blood pressure (systolic and diastolic) and heart rate were measured every 3 minutes, and blood glucose concentrations every 15 minutes. Systolic and diastolic blood pressure fell (P < .0001), and heart rate and blood glucose increased (P = .0001 for both) over time, during all 3 infusions. Between t = -2-120 minutes, there was no difference in systolic blood pressure (P = .20), diastolic blood pressure (P = .61), or heart rate (P = .09) over the study days. There was also no significant difference in the glycemic response to the infusions. We conclude that in healthy older subjects, glucose concentration does not affect the blood pressure or heart rate responses to intraduodenal glucose and that, therefore, the magnitude of the postprandial fall in blood pressure induced by oral glucose is likely to depend primarily on the small intestinal glucose load.
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Affiliation(s)
- Diana Gentilcore
- Department of Medicine, University of Adelaide, Royal Adelaide Hospital, South Australia, Australia
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