1
|
Rios FJ, Montezano AC, Camargo LL, Touyz RM. Impact of Environmental Factors on Hypertension and Associated Cardiovascular Disease. Can J Cardiol 2023; 39:1229-1243. [PMID: 37422258 DOI: 10.1016/j.cjca.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/24/2023] [Accepted: 07/02/2023] [Indexed: 07/10/2023] Open
Abstract
Hypertension is the primary cause of cardiovascular diseases and is responsible for nearly 9 million deaths worldwide annually. Increasing evidence indicates that in addition to pathophysiologic processes, numerous environmental factors, such as geographic location, lifestyle choices, socioeconomic status, and cultural practices, influence the risk, progression, and severity of hypertension, even in the absence of genetic risk factors. In this review, we discuss the impact of some environmental determinants on hypertension. We focus on clinical data from large population studies and discuss some potential molecular and cellular mechanisms. We highlight how these environmental determinants are interconnected, as small changes in one factor might affect others, and further affect cardiovascular health. In addition, we discuss the crucial impact of socioeconomic factors and how these determinants influence diverse communities with economic disparities. Finally, we address opportunities and challenges for new research to address gaps in knowledge on understanding molecular mechanisms whereby environmental factors influence development of hypertension and associated cardiovascular disease.
Collapse
Affiliation(s)
- Francisco J Rios
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.
| | - Augusto C Montezano
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Livia L Camargo
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Rhian M Touyz
- Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.
| |
Collapse
|
2
|
Timpka S, Melander O, Engström G, Elmståhl S, Nilsson PM, Lind L, Pihlsgård M, Enhörning S. Short-term association between outdoor temperature and the hydration-marker copeptin: a pooled analysis in five cohorts. EBioMedicine 2023; 95:104750. [PMID: 37556945 PMCID: PMC10432996 DOI: 10.1016/j.ebiom.2023.104750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Whereas outdoor temperature is linked to both mortality and hydration status, the hormone vasopressin, measured through the surrogate copeptin, is a marker of cardiometabolic risk and hydration. We recently showed that copeptin has a seasonal pattern with higher plasma concentration in winter. Here, we aimed to investigate the association between outdoor temperature and copeptin. METHODS Copeptin was analysed in fasting plasma from five cohorts in Malmö, Sweden (n = 26,753, 49.7% men, age 18-86 years). We utilized a multivariable adjusted non-linear spline model with four knots to investigate the association between short-term temperature (24 h mean apparent) and log copeptin z-score. FINDINGS We found a distinct non-linear association between temperature and log copeptin z-score, with both moderately low and high temperatures linked to higher copeptin concentration (p < 0.0001). Between 0 °C and nadir at the 75th temperature percentile (corresponding to 14.3 °C), log copeptin decreased 0.13 z-scores (95% CI 0.096; 0.16), which also inversely corresponded to the increase in z-score log copeptin between the nadir and 21.3 °C. INTERPRETATION The J-shaped association between short-term temperature and copeptin resembles the J-shaped association between temperature and mortality. Whereas the untangling of temperature from other seasonal effects on hydration warrants further study, moderately increased water intake constitutes a feasible intervention to lower vasopressin and might mitigate adverse health effects of both moderately cold and hot outdoor temperatures. FUNDING Swedish Research Council, Å Wiberg, M Stephen, A Påhlsson, Crafoord and Swedish Heart-Lung Foundations, Swedish Society for Medical Research and Swedish Society of Medicine.
Collapse
Affiliation(s)
- Simon Timpka
- Perinatal and Cardiovascular Epidemiology, Lund University Diabetes Centre, Department of Clinical Sciences in Malmö, Lund University, Malmö, Sweden; Department of Obstetrics and Gynecology, Skåne University Hospital, Malmö, Sweden
| | - Olle Melander
- Department of Clinical Sciences in Malmö, Lund University, Malmö, Sweden; Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
| | - Gunnar Engström
- Department of Clinical Sciences in Malmö, Lund University, Malmö, Sweden
| | - Sölve Elmståhl
- Department of Clinical Sciences in Malmö, Division of Geriatric Medicine, Lund University, Malmö, Sweden
| | - Peter M Nilsson
- Internal Medicine - Epidemiology, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Lars Lind
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Mats Pihlsgård
- Perinatal and Cardiovascular Epidemiology, Lund University Diabetes Centre, Department of Clinical Sciences in Malmö, Lund University, Malmö, Sweden
| | - Sofia Enhörning
- Perinatal and Cardiovascular Epidemiology, Lund University Diabetes Centre, Department of Clinical Sciences in Malmö, Lund University, Malmö, Sweden; Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden.
| |
Collapse
|
3
|
Sixtus RP, Gray C, Berry MJ, Dyson RM. Preterm-born individuals: a vulnerable population at risk of cardiovascular morbidity and mortality during thermal extremes? Exp Physiol 2023; 108:1011-1025. [PMID: 37084061 PMCID: PMC10988436 DOI: 10.1113/ep091152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 04/03/2023] [Indexed: 04/22/2023]
Abstract
NEW FINDINGS What is the topic of this review? Thermal extremes disproportionately affect populations with cardiovascular conditions. Preterm birth, across all gestational age ranges below 37 weeks, has been identified as a non-modifiable risk factor for cardiovascular disease. The hypothesis is presented that individuals born preterm are at an increased risk of cardiovascular morbidity and mortality during thermal extremes. What advances does it highlight? Cardiovascular stress tests performed in preterm-born populations, from infancy through adulthood, highlight a progression of cardiovascular dysfunction accelerating through adolescence and adulthood. This dysfunction has many similarities with populations known to be at risk in thermal extremes. ABSTRACT Preterm-born individuals are a uniquely vulnerable population. Preterm exposure to the extrauterine environment and the (mal)adaptations that occur during the transitional period can result in alterations to their macro- and micro-physiological state. The physiological adaptations that increase survival in the short term may place those born preterm on a trajectory of lifelong dysfunction and later-life decompensation. Cardiovascular compensation in children and adolescents, which masks this trajectory of dysfunction, is overcome under stress, such that the functional cardiovascular capacity is reduced and recovery impaired following physiological stress. This has implications for their response to thermal stress. As the Anthropocene introduces greater changes in our environment, thermal extremes will impact vulnerable populations as yet unidentified in the climate change context. Here, we present the hypothesis that individuals born preterm are a vulnerable population at an increased risk of cardiovascular morbidity and mortality during thermal extremes.
Collapse
Affiliation(s)
- Ryan Phillip Sixtus
- Department of Paediatrics and Child HealthUniversity of OtagoWellingtonNew Zealand
| | - Clint Gray
- Department of Paediatrics and Child HealthUniversity of OtagoWellingtonNew Zealand
| | - Mary Judith Berry
- Department of Paediatrics and Child HealthUniversity of OtagoWellingtonNew Zealand
| | - Rebecca Maree Dyson
- Department of Paediatrics and Child HealthUniversity of OtagoWellingtonNew Zealand
| |
Collapse
|
4
|
Sixtus RP, Berry MJ, Gray CL, Dyson RM. A novel whole-body thermal stress test for monitoring cardiovascular responses in Guinea pigs. J Therm Biol 2023; 113:103500. [PMID: 37055107 DOI: 10.1016/j.jtherbio.2023.103500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 01/27/2023] [Accepted: 02/04/2023] [Indexed: 03/12/2023]
Abstract
Cardiovascular disease is a leading cause of morbidity and mortality worldwide. Stress tests are frequently employed to expose early signs of cardiovascular dysfunction or disease and can be employed, for example, in the context of preterm birth. We aimed to establish a safe and effective thermal stress test to examine cardiovascular function. Guinea pigs were anaesthetized using a 0.8% isoflurane, 70% N2O mix. ECG, non-invasive blood pressure, laser Doppler flowmetry, respiratory rate, and an array of skin and rectal thermistors were applied. A physiologically relevant heating and a cooling thermal stress test was developed. Upper and lower thermal limits for core body temperature were set at 41.5 OC and 34 OC, for the safe recovery of animals. This protocol therefore presents a viable thermal stress test for use in guinea pig models of health and disease that facilitates exploration of whole-system cardiovascular function.
Collapse
Affiliation(s)
- Ryan P Sixtus
- Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand.
| | - Mary J Berry
- Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand
| | - Clint L Gray
- Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand
| | - Rebecca M Dyson
- Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand
| |
Collapse
|
5
|
Abstract
The pathogenesis of metabolic diseases such as obesity and type 2 diabetes are characterized by a progressive dysregulation in energy partitioning, often leading to end-organ complications. One emerging approach proposed to target this metabolic dysregulation is the application of mild cold exposure. In healthy individuals, cold exposure can increase energy expenditure and whole body glucose and fatty acid utilization. Repeated exposures can lower fasting glucose and insulin levels and improve dietary fatty acid handling, even in healthy individuals. Despite its apparent therapeutic potential, little is known regarding the effects of cold exposure in populations for which this stimulation could benefit the most. The few studies available have shown that both acute and repeated exposures to the cold can improve insulin sensitivity and reduce fasting glycemia in individuals with type 2 diabetes. However, critical gaps remain in understanding the prolonged effects of repeated cold exposures on glucose regulation and whole body insulin sensitivity in individuals with metabolic syndrome. Much of the metabolic benefits appear to be attributable to the recruitment of shivering skeletal muscles. However, further work is required to determine whether the broader recruitment of skeletal muscles observed during cold exposure can confer metabolic benefits that surpass what has been historically observed from endurance exercise. In addition, although cold exposure offers unique cardiovascular responses for a physiological stimulus that increases energy expenditure, further work is required to determine how acute and repeated cold exposure can impact cardiovascular responses and myocardial function across a broader scope of individuals.
Collapse
Affiliation(s)
- Yoanna M Ivanova
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Denis P Blondin
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada.,Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| |
Collapse
|
6
|
Dillon GA, Lichter ZS, Alexander LM, Vianna LC, Wang J, Fadel PJ, Greaney JL. Reproducibility of the neurocardiovascular responses to common laboratory-based sympathoexcitatory stimuli in young adults. J Appl Physiol (1985) 2020; 129:1203-1213. [PMID: 32940559 DOI: 10.1152/japplphysiol.00210.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The magnitude of blood pressure (BP) and muscle sympathetic nerve activity (MSNA) responses to laboratory stressors is commonly used to compare neurocardiovascular responsiveness between groups and conditions. However, no studies have rigorously examined the reproducibility of BP and MSNA responsiveness. Here, we assess the within-visit reproducibility of BP (finger photoplethysmography) and MSNA (microneurography) responses to isometric handgrip (HG) and postexercise ischemia (PEI) in young healthy adults (n = 30). In a subset (n = 21), we also examined the between-visit reproducibility of responsiveness to HG, PEI, and the cold pressor test (CPT). Intraclass correlation coefficients (ICCs) were used as a primary reproducibility measure (e.g., ICC >0.75 is considered very good). Within a visit, the increase in mean arterial pressure during HG [ICC = 0.85 (0.69-0.93); P < 0.001] and PEI [ICC = 0.85 (0.69-0.93); P < 0.001] demonstrated very good reproducibility. Furthermore, the between-visit reproducibility of the pressor response to HG [ICC = 0.85 (0.62-0.94); P < 0.001], PEI [ICC = 0.84 (CI = 0.58-0.94); P < 0.001], and the CPT [ICC = 0.89 (0.72-0.95) P < 0.001]) were also very good. However, there was greater variability in both the within- [HG: ICC = 0.58 (-0.22-0.85), P = 0.001; PEI: ICC = 0.33 (-0.24-0.69), P = 0.042] and between-visit reproducibility of MSNA responsiveness [HG: ICC = 0.87 (0.53-0.96), P = 0.001; PEI: ICC = 0.24 (-0.62-0.78), P = 0.27; CPT: ICC = 0.77 (0.29-0.93), P = 0.007]. The magnitude of the BP response to several standard laboratory stimuli was very good, whereas the variability of the MSNA response to these perturbations was generally less consistent, particularly during PEI. These data provide novel insight for both study design and data interpretation when comparing neurocardiovascular responsiveness between different conditions, groups, or studies, as well as before and after interventions/treatments.NEW & NOTEWORTHY The magnitude of the increases in blood pressure and muscle sympathetic nerve activity in response to sympathoexcitatory stimuli such as static handgrip, postexercise ischemia, and the cold pressor test are commonly used to assess neurocardiovascular responsiveness. However, limited studies have comprehensively examined the reproducibility of these responses. We demonstrate that the reproducibility of the pressor response to these perturbations was very good within an individual, whereas the reproducibility of the MSNA response was less consistent.
Collapse
Affiliation(s)
- Gabrielle A Dillon
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania
| | - Zachary S Lichter
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania
| | - Lacy M Alexander
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania
| | - Lauro C Vianna
- NeuroV̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Brazil
| | - Jing Wang
- College of Nursing, The University of Texas at Arlington, Arlington, Texas
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | - Jody L Greaney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania.,Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| |
Collapse
|
7
|
Mejía-Mejía E, Budidha K, Abay TY, May JM, Kyriacou PA. Heart Rate Variability (HRV) and Pulse Rate Variability (PRV) for the Assessment of Autonomic Responses. Front Physiol 2020; 11:779. [PMID: 32792970 PMCID: PMC7390908 DOI: 10.3389/fphys.2020.00779] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 06/15/2020] [Indexed: 12/29/2022] Open
Abstract
Introduction: Heart Rate Variability (HRV) and Pulse Rate Variability (PRV), are non-invasive techniques for monitoring changes in the cardiac cycle. Both techniques have been used for assessing the autonomic activity. Although highly correlated in healthy subjects, differences in HRV and PRV have been observed under various physiological conditions. The reasons for their disparities in assessing the degree of autonomic activity remains unknown. Methods: To investigate the differences between HRV and PRV, a whole-body cold exposure (CE) study was conducted on 20 healthy volunteers (11 male and 9 female, 30.3 ± 10.4 years old), where PRV indices were measured from red photoplethysmography signals acquired from central (ear canal, ear lobe) and peripheral sites (finger and toe), and HRV indices from the ECG signal. PRV and HRV indices were used to assess the effects of CE upon the autonomic control in peripheral and core vasculature, and on the relationship between HRV and PRV. The hypotheses underlying the experiment were that PRV from central vasculature is less affected by CE than PRV from the peripheries, and that PRV from peripheral and central vasculature differ with HRV to a different extent, especially during CE. Results: Most of the PRV time-domain and Poincaré plot indices increased during cold exposure. Frequency-domain parameters also showed differences except for relative-power frequency-domain parameters, which remained unchanged. HRV-derived parameters showed a similar behavior but were less affected than PRV. When PRV and HRV parameters were compared, time-domain, absolute-power frequency-domain, and non-linear indices showed differences among stages from most of the locations. Bland-Altman analysis showed that the relationship between HRV and PRV was affected by CE, and that it recovered faster in the core vasculature after CE. Conclusion: PRV responds to cold exposure differently to HRV, especially in peripheral sites such as the finger and the toe, and may have different information not available in HRV due to its non-localized nature. Hence, multi-site PRV shows promise for assessing the autonomic activity on different body locations and under different circumstances, which could allow for further understanding of the localized responses of the autonomic nervous system.
Collapse
Affiliation(s)
- Elisa Mejía-Mejía
- Research Centre for Biomedical Engineering (RCBE), School of Mathematics, Engineering and Computer Science, University of London, London, United Kingdom
| | - Karthik Budidha
- Research Centre for Biomedical Engineering (RCBE), School of Mathematics, Engineering and Computer Science, University of London, London, United Kingdom
| | - Tomas Ysehak Abay
- Research Centre for Biomedical Engineering (RCBE), School of Mathematics, Engineering and Computer Science, University of London, London, United Kingdom
| | - James M May
- Research Centre for Biomedical Engineering (RCBE), School of Mathematics, Engineering and Computer Science, University of London, London, United Kingdom
| | - Panayiotis A Kyriacou
- Research Centre for Biomedical Engineering (RCBE), School of Mathematics, Engineering and Computer Science, University of London, London, United Kingdom
| |
Collapse
|
8
|
Knight EL, Giuliano RJ, Shank SW, Clarke MM, Almeida DM. Parasympathetic and sympathetic nervous systems interactively predict change in cognitive functioning in midlife adults. Psychophysiology 2020; 57:e13622. [PMID: 32598489 DOI: 10.1111/psyp.13622] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 12/18/2022]
Abstract
The two branches of the autonomic nervous system (ANS) have been individually linked to changes in cognitive functioning: The parasympathetic nervous system (PNS) has been associated with healthy cognitive aging, whereas excessive sympathetic nervous system (SNS) activity has been linked to heightened cognitive decline. Despite these separate findings and despite the integrative nature of the ANS, little work has examined the two branches simultaneously to better understand their interactive effects on changes in cognitive functioning in midlife adults. We examined cognitive change in two waves of the Midlife in the United States (MIDUS) study cognitive project and indexed PNS and SNS activity from heart rate variability and epinephrine levels, respectively, from the MIDUS biomarker project (minimum n = 843, 57.9% female, mean age at first wave = 53.8 years). Our findings indicate that greater PNS responsivity (i.e., greater withdrawal and greater recovery) in response to cognitive challenge is associated with attenuated cognitive decline, but only among individuals with low SNS levels; at higher SNS levels, the effects of the PNS on cognitive decline are attenuated. These results suggest that future research targeting the ANS and cognitive aging should consider both ANS branch's effects simultaneously.
Collapse
Affiliation(s)
- Erik L Knight
- Center for Healthy Aging, Pennsylvania State University, University Park, PA, USA.,Department of Biobehavioral Health, Pennsylvania State University, University Park, PA, USA
| | - Ryan J Giuliano
- Department of Psychology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sean W Shank
- Department of Kinesiology, Pennsylvania State University, University Park, PA, USA
| | - Megan M Clarke
- Department of Kinesiology, Pennsylvania State University, University Park, PA, USA
| | - David M Almeida
- Center for Healthy Aging, Pennsylvania State University, University Park, PA, USA.,Department of Human Development and Family Studies, Pennsylvania State University, University Park, PA, USA
| |
Collapse
|
9
|
Limberg JK, Casey DP, Trinity JD, Nicholson WT, Wray DW, Tschakovsky ME, Green DJ, Hellsten Y, Fadel PJ, Joyner MJ, Padilla J. Assessment of resistance vessel function in human skeletal muscle: guidelines for experimental design, Doppler ultrasound, and pharmacology. Am J Physiol Heart Circ Physiol 2019; 318:H301-H325. [PMID: 31886718 DOI: 10.1152/ajpheart.00649.2019] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The introduction of duplex Doppler ultrasound almost half a century ago signified a revolutionary advance in the ability to assess limb blood flow in humans. It is now widely used to assess blood flow under a variety of experimental conditions to study skeletal muscle resistance vessel function. Despite its pervasive adoption, there is substantial variability between studies in relation to experimental protocols, procedures for data analysis, and interpretation of findings. This guideline results from a collegial discussion among physiologists and pharmacologists, with the goal of providing general as well as specific recommendations regarding the conduct of human studies involving Doppler ultrasound-based measures of resistance vessel function in skeletal muscle. Indeed, the focus is on methods used to assess resistance vessel function and not upstream conduit artery function (i.e., macrovasculature), which has been expertly reviewed elsewhere. In particular, we address topics related to experimental design, data collection, and signal processing as well as review common procedures used to assess resistance vessel function, including postocclusive reactive hyperemia, passive limb movement, acute single limb exercise, and pharmacological interventions.
Collapse
Affiliation(s)
- Jacqueline K Limberg
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri
| | - Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,François M. Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Fraternal Order of Eagles Diabetes Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | | | - D Walter Wray
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Michael E Tschakovsky
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Daniel J Green
- School of Human Sciences (Exercise and Sport Science), University of Western Australia, Perth, Western Australia, Australia
| | - Ylva Hellsten
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, Texas
| | | | - Jaume Padilla
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| |
Collapse
|
10
|
Yang HH, Li XL, Zhang WG, Figueroa A, Chen LH, Qin LQ. Effect of oral L-citrulline on brachial and aortic blood pressure defined by resting status: evidence from randomized controlled trials. Nutr Metab (Lond) 2019; 16:89. [PMID: 31889969 PMCID: PMC6933755 DOI: 10.1186/s12986-019-0415-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 12/12/2019] [Indexed: 02/06/2023] Open
Abstract
Background Experimental evidence indicates that oral L-citrulline (L-Cit) may reduce resting blood pressure (BP) as well as BP responses to exercise and cold exposure (non-resting). However, results from human intervention trials are inconsistent. This study aims to summarize the clinical evidence regarding the effects of L-Cit supplementation on brachial systolic blood pressure (SBP), brachial diastolic blood pressure (DBP), in addition to aortic SBP and aortic DBP at rest and non-resting conditions. Methods Multiple databases including PubMed, Embase, Cochrane library, Web of Science, and Clinical Trials were searched systematically. Randomized controlled trials of human participants were quantitatively meta-analyzed. Results Fourteen trials contained in eight studies were available for quantitative syntheses for brachial BP. Results showed that L-Cit supplementation significantly reduced both brachial SBP (− 4.490 mmHg, 95% CI: − 7.332 to − 1.648, P = 0.002) and brachial DBP (− 3.629 mmHg, 95% CI: − 5.825 to − 1.434, P = 0.001). Nine of the trials were meta-analyzed for aortic BP which showed that L-Cit intervention significantly reduced aortic SBP (− 6.763 mmHg, 95% CI: − 10.991 to − 2.534, P = 0.002), but not aortic DBP (− 3.396 mmHg, 95% CI: − 7.418 to 0.627, P = 0.098). The observed reducing effects of L-Cit appeared stronger for non-resting than for resting brachial SBP (P for difference = 0.044). Conclusion L-Cit supplementation significantly decreased non-resting brachial and aortic SBP. Brachial DBP was significantly lowered by L-Cit regardless of resting status. Given the relatively small number of available trials in the stratified analyses and the potential limitations of these trials, the present findings should be interpreted cautiously and need to be confirmed in future well-designed trials with a larger sample size.
Collapse
Affiliation(s)
- Huan-Huan Yang
- 1Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, 215123 China
| | - Xin-Li Li
- 1Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, 215123 China
| | | | - Arturo Figueroa
- 3Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, TX 79409 USA
| | - Li-Hua Chen
- 1Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, 215123 China
| | - Li-Qiang Qin
- 1Department of Nutrition and Food Hygiene, School of Public Health, Soochow University, Suzhou, 215123 China
| |
Collapse
|
11
|
Peçanha T, Low D, de Brito LC, Fecchio RY, de Sousa PN, da Silva-Júnior ND, de Abreu AP, da Silva GV, Mion-Junior D, Forjaz CLDM. Effects of postexercise cooling on heart rate recovery in normotensive and hypertensive men. Clin Physiol Funct Imaging 2019; 40:114-121. [PMID: 31769592 DOI: 10.1111/cpf.12612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 11/23/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Postexercise heart rate recovery (HRR) is determined by cardiac autonomic restoration after exercise and is reduced in hypertension. Postexercise cooling accelerates HRR in healthy subjects, but its effects in a population with cardiac autonomic dysfunction, such as hypertensives (HT), may be blunted. This study assessed and compared the effects of postexercise cooling on HRR and cardiac autonomic regulation in HT and normotensive (NT) subjects. METHODS Twenty-three never-treated HT (43 ± 8 years) and 25 NT (45 ± 8 years) men randomly underwent two exercise sessions (30 min of cycling at 70% VO2peak ) followed by 15 min of recovery. In one randomly allocated session, a fan was turned on in front of the subject during the recovery (cooling), while in the other session, no cooling was performed (control). HRR was assessed by heart rate reductions after 60 s (HRR60s) and 300 s (HRR300s) of recovery, short-term time constant of HRR (T30) and the time constant of the HRR after exponential fitting (HRRτ). HRV was assessed using time- and frequency-domain indices. RESULTS HRR and HRV responses in the cooling and control sessions were similar between the HT and NT. Thus, in both groups, postexercise cooling equally accelerated HRR (HRR300s = 39±12 versus 36 ± 10 bpm, P≤0·05) and increased postexercise HRV (lnRMSSD = 1·8 ± 0·7 versus 1·6 ± 0·7 ms, P≤0·05). CONCLUSION Differently from the hypothesis, postexercise cooling produced similar improvements in HRR in HT and NT men, likely by an acceleration of cardiac parasympathetic reactivation and sympathetic withdrawal. These results suggest that postexercise cooling equally accelerates HRR in hypertensive and normotensive subjects.
Collapse
Affiliation(s)
- Tiago Peçanha
- Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - David Low
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Leandro Campos de Brito
- Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Rafael Yokoyama Fecchio
- Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Patrícia Nascimento de Sousa
- Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Natan Daniel da Silva-Júnior
- Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Andrea Pio de Abreu
- Hypertension Unit, General Hospital, University of São Paulo, São Paulo, Brazil
| | | | - Décio Mion-Junior
- Hypertension Unit, General Hospital, University of São Paulo, São Paulo, Brazil
| | | |
Collapse
|
12
|
Greaney JL, Stanhewicz AE, Kenney WL. Chronic statin therapy is associated with enhanced cutaneous vascular responsiveness to sympathetic outflow during passive heat stress. J Physiol 2019; 597:4743-4755. [PMID: 31397898 DOI: 10.1113/jp278237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 08/08/2019] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Impairments in both central sympathetic and peripheral microvascular function contribute to blunted reflex cutaneous vasodilatation during heat stress in healthy older adults. Hypercholesterolaemia is associated with decrements in neurovascular function; however, little is known about the impact of hypercholesterolaemia on the integrated responses to heat stress. Further, whether chronic statin therapy alters skin sympathetic outflow or its relation to cutaneous vascular conductance during heat stress is unknown. We demonstrate that reflex cutaneous vasodilatation is impaired in older hypercholesterolaemic adults but not in formerly hypercholesterolaemic adults currently treated with a statin compared to age-matched controls. Additionally, chronic statin treatment-induced improvements in reflex vasodilatation are mediated, in part, by increases in end-organ responsiveness to efferent sympathetic outflow during whole-body heating. These data add to the growing body of literature substantiating the beneficial pleiotropic neurovascular effects of chronic statin treatment and provide further support for the use of statins to confer additional cardioprotective benefits in older adults. ABSTRACT Attenuated reflex cutaneous vasodilatation in healthy human ageing is mediated by alterations in both central (sympathetic outflow) and peripheral (microvascular endothelial) function. Hypercholesterolaemia is associated with further impairments in neurovascular function. HMG-CoA reductase inhibitors (statins) improve cutaneous endothelium-dependent dilatation; however, whether statin therapy alters skin sympathetic nervous system activity (SSNA) or its relation to cutaneous vascular conductance (CVC) during passive heat stress is unknown. We hypothesized that (1) hypercholesterolaemic older adults would demonstrate blunted increases in both SSNA and CVC during passive heating and (2) chronic statin treatment would improve the response range and sensitivity of the SSNA:CVC relation. Reflex vasodilatation in response to a 1.0°C rise in oral temperature (Tor ; water perfused suit) was induced in 13 healthy normocholesterolaemic adults (62 ± 2 years; LDL = 113 ± 7 mg/dl), 10 hypercholesterolaemic adults (60 ± 1 years; LDL = 183 ± 2 mg/dl), and 10 previously hypercholesterolaemic adults (64 ± 1 years; LDL = 102 ± 2 mg/dl) treated with lipophilic statin (10-40 mg daily). SSNA (peroneal microneurography) and red cell flux (laser-Doppler flowmetry) in the innervated dermatome (dorsum of foot) were continuously measured. Reflex vasodilatation was blunted in hypercholesterolaemic adults, but not in statin-treated adults, compared to normocholesterolaemic adults (at ∆Tor = 1.0°C: normal = 36 ± 1%CVCmax , high = 32 ± 1%CVCmax , statin = 38 ± 1%CVCmax ; P < 0.01). ∆SSNA was not different (at ∆Tor = 1.0°C: normal: ∆ = 393 ± 96%, high: ∆ = 311 ± 120%, statin: ∆ = 256 ± 90%; P = 0.11). The slope of the SSNA:CVC relation was blunted in hypercholesterolaemic adults (0.02 ± 0.03%CVCmax /%baseline ) compared to both normocholesterolaemic (0.09 ± 0.02%CVCmax /%baseline ; P = 0.024) and statin-treated (0.12 ± 0.05%CVCmax /%baseline ; P = 0.03) adults. Chronic statin treatment improves reflex cutaneous vasodilatation in formerly hypercholesterolaemic older adults by increasing end-organ responsiveness to sympathetic outflow during passive heat stress.
Collapse
Affiliation(s)
- Jody L Greaney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA.,Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, USA
| | - Anna E Stanhewicz
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
| | - W Larry Kenney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
| |
Collapse
|
13
|
Incognito AV, Duplea S, Lee JB, Sussman J, Shepherd AD, Doherty CJ, Cacoilo JA, Notay K, Millar PJ. Arterial baroreflex regulation of muscle sympathetic nerve activity at rest and during stress. J Physiol 2019; 597:4729-4741. [DOI: 10.1113/jp278376] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/31/2019] [Indexed: 12/31/2022] Open
Affiliation(s)
- Anthony V. Incognito
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Sergiu‐Gabriel Duplea
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Jordan B. Lee
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Jess Sussman
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Andrew D. Shepherd
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Connor J. Doherty
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | | | - Karambir Notay
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
| | - Philip J. Millar
- Department of Human Health and Nutritional SciencesUniversity of Guelph Guelph ON Canada
- Toronto General Research Institute Toronto ON Canada
| |
Collapse
|
14
|
Hissen SL, Sayed KE, Macefield VG, Brown R, Taylor CE. The Stability and Repeatability of Spontaneous Sympathetic Baroreflex Sensitivity in Healthy Young Individuals. Front Neurosci 2018; 12:403. [PMID: 29962929 PMCID: PMC6010576 DOI: 10.3389/fnins.2018.00403] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/25/2018] [Indexed: 01/18/2023] Open
Abstract
Spontaneous sympathetic baroreflex sensitivity (BRS) is a valuable tool for assessing how well the baroreflex buffers beat-to-beat changes in blood pressure. However, there has yet to be a study involving appropriate statistical tests to examine the stability of sympathetic BRS within an experimental session and the repeatability between separate sessions. The aim of this study was to use intra-class correlations, ordinary least products regression, and Bland–Altman analyses to examine the stability and repeatability of spontaneous sympathetic BRS assessment. In addition, the influence of recording duration on values of BRS was assessed. In eighty-four healthy young individuals (49 males, 35 females), continuous measurements of blood pressure, heart rate and muscle sympathetic nerve activity (MSNA) were recorded for 10 min. In a subgroup of 13 participants (11 male, 2 female) the measurements were repeated on a separate day. Sympathetic BRS was quantified using MSNA burst incidence (BRSinc) and total MSNA (BRStotal) for the first 5-min period, the second 5-min period, and a 2-min segment taken from the second 5-min period. Intra-class correlation coefficients indicated moderate stability in sympathetic BRSinc and BRStotal between the first and second 5-min periods in males (BRSincr = 0.63, BRStotalr = 0.78) and females (BRSincr = 0.61, BRStotalr = 0.47) with no proportional bias, but with fixed bias for BRSinc in females. When comparing the first 5-min with the 2-min period (n = 76), the intra-class correlation coefficient indicated poor to moderate repeatability in sympathetic BRSinc and BRStotal for males (BRSincr = -0.01, BRStotalr = 0.70) and females (BRSincr = 0.46, BRStotalr = 0.39). However, Bland–Altman analysis revealed a fixed bias for BRStotal in males and proportional bias for BRStotal in females, with lower BRS values for 5-min recordings. In the subgroup, intra-class correlations indicated moderate repeatability for measures of BRSinc (9 male, 2 female, r = 0.63) and BRStotal (6 male, 2 female, r = 0.68) assessed using 5-min periods recorded on separate days. However, Bland–Altman analysis indicated proportional bias for BRSinc and fixed bias for BRStotal. In conclusion, measures of spontaneous sympathetic BRS are moderately stable and repeatable within and between testing sessions in healthy young adults, provided that the same length of recording is used when making comparisons.
Collapse
Affiliation(s)
- Sarah L Hissen
- School of Science and Health, Western Sydney University, Sydney, NSW, Australia
| | - Khadigeh El Sayed
- School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Vaughan G Macefield
- School of Medicine, Western Sydney University, Sydney, NSW, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Neuroscience Research Australia, Sydney, NSW, Australia
| | - Rachael Brown
- School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Chloe E Taylor
- School of Science and Health, Western Sydney University, Sydney, NSW, Australia.,School of Medicine, Western Sydney University, Sydney, NSW, Australia
| |
Collapse
|
15
|
Abstract
Both acute and prolonged cold exposure affect cardiovascular responses, which may be modified by an underlying cardiovascular disease. In addition, exercise in a cold environment increases cardiovascular strain further, but its effects among persons with cardiovascular diseases are not well known. Controlled studies employing whole-body or local cold exposure demonstrate comparable or augmented increase in cardiac workload, but aggravated cutaneous vasoconstriction in persons with mild hypertension. A strong sympathetic stimulation of a cold pressor test, increases cardiac workload in persons with coronary artery disease (CAD), but does not markedly differ from those with less severe disease or healthy. However, cold exposure reduces myocardial oxygen supply in CAD, which may lead to ischemia. Exercise in cold often augments cardiac workload in persons with CAD more than when performed in thermoneutral conditions. At the same time, reduced myocardial perfusion may lead to earlier ischemia, angina and impaired performance. Also having a heart failure deteriorates submaximal and maximal performance in the cold. Antianginal medication is beneficial in the cold in lowering blood pressure, but does not affect the magnitude of cold-related cardiovascular responses in hypertension. Similarly, the use of blood pressure lowering medication improves exercise performance in cold both among persons with CAD and heart failure. Both the acute and seasonal effects of cold and added with exercise may contribute to the higher morbidity and mortality of those with cardiovascular diseases. Yet, more controlled studies for understanding the pathophysiological mechanisms behind the adverse cold-related health effects are warranted.
Collapse
Affiliation(s)
- Tiina M Ikäheimo
- Center For Environmental and Respiratory Health Research, University of Oulu, FI-90014 University of Oulu, Oulu, Finland.,Medical Research Center, University of Oulu and Oulu University Hospital, FI-90029 OYS, Oulu, Finland
| |
Collapse
|
16
|
Schlader ZJ, Coleman GL, Sackett JR, Sarker S, Chapman CL, Hostler D, Johnson BD. Behavioral thermoregulation in older adults with cardiovascular co-morbidities. Temperature (Austin) 2017; 5:70-85. [PMID: 29687045 PMCID: PMC5902208 DOI: 10.1080/23328940.2017.1379585] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 09/01/2017] [Accepted: 09/06/2017] [Indexed: 12/21/2022] Open
Abstract
We tested the hypotheses that older adults with cardiovascular co-morbidities will demonstrate greater changes in body temperature and exaggerated changes in blood pressure before initiating thermal behavior. We studied twelve healthy younger adults (Younger, 25 ± 4 y) and six older adults ('At Risk', 67 ± 4 y) taking prescription medications for at least two of the following conditions: hypertension, type II diabetes, hypercholesterolemia. Subjects underwent a 90-min test in which they voluntarily moved between cool (18.1 ± 1.8°C, RH: 29 ± 5%) and warm (40.2 ± 0.3°C, RH: 20 ± 0%) rooms when they felt 'too cool' (C→W) or 'too warm' (W→C). Mean skin and intestinal temperatures and blood pressure were measured. Data were analyzed as a change from pretest baseline. Changes in mean skin temperature were not different between groups at C→W (Younger: +0.2 ± 0.8°C, 'At Risk': +0.7 ± 1.8°C, P = 0.51) or W→C (Younger: +2.7 ± 0.6°C, 'At Risk': +2.9 ± 1.9°C, P = 0.53). Changes in intestinal temperature were not different at C→W (Younger: 0.0 ± 0.1°C, 'At Risk': +0.1 ± 0.2, P = 0.11), but differed at W→C (-0.1 ± 0.2°C vs. +0.1 ± 0.3°C, P = 0.02). Systolic pressure at C→W increased (Younger: +10 ± 9 mmHg, 'At Risk': +24 ± 17 mmHg) and at W→C decreased (Younger: -4 ± 13 mmHg, 'At Risk': -23 ± 19 mmHg) to a greater extent in 'At Risk' (P ≤ 0.05). Differences were also apparent for diastolic pressure at C→W (Younger: -2 ± 4 mmHg, 'At Risk': +17 ± 23 mmHg, P < 0.01), but not at W→C (Younger Y: +4 ± 13 mmHg, 'At Risk': -1 ± 6 mmHg, P = 0.29). Despite little evidence for differential control of thermal behavior, the initiation of behavior in 'at risk' older adults is preceded by exaggerated blood pressure responses.
Collapse
Affiliation(s)
- Zachary J. Schlader
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Gregory L. Coleman
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - James R. Sackett
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Suman Sarker
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Christopher L. Chapman
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - David Hostler
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Blair D. Johnson
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| |
Collapse
|