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Jahn LA, Hartline LM, Nguyen T, Aylor K, Horton WB, Liu Z, Barrett EJ. Empagliflozin improves vascular insulin sensitivity and muscle perfusion in persons with type 2 diabetes. Am J Physiol Endocrinol Metab 2024; 326:E258-E267. [PMID: 38170166 PMCID: PMC11193530 DOI: 10.1152/ajpendo.00267.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 12/14/2023] [Accepted: 12/21/2023] [Indexed: 01/05/2024]
Abstract
Sodium glucose cotransporter 2 inhibitors (SGLT2is) improved major adverse cardiovascular events (MACE), heart failure, and renal outcomes in large trials; however, a thorough understanding of the vascular physiological changes contributing to these responses is lacking. We hypothesized that SGLT2i therapy would diminish vascular insulin resistance and improve hemodynamic function, which could improve clinical outcomes. To test this, we treated 11 persons with type 2 diabetes for 12 wk with 10 mg/day empagliflozin and measured vascular stiffness, endothelial function, peripheral and central arterial pressures, skeletal and cardiac muscle perfusion, and vascular biomarkers before and at 120 min of a euglycemic hyperinsulinemic clamp at weeks 0 and 12. We found that before empagliflozin treatment, insulin infusion lowered peripheral and central aortic systolic pressure (P < 0.05) and muscle microvascular blood flow (P < 0.01), but showed no effect on other vascular measures. Following empagliflozin, insulin infusion improved endothelial function (P = 0.02), lowered peripheral and aortic systolic (each P < 0.01), diastolic (each P < 0.05), mean arterial (each P < 0.01), and pulse pressures (each P < 0.02), altered endothelial biomarker expression, and decreased radial artery forward and backward pressure amplitude (each P = 0.02). Empagliflozin also improved insulin-mediated skeletal and cardiac muscle microvascular perfusion (each P < 0.05). We conclude that empagliflozin enhances insulin's vascular actions, which could contribute to the improved cardiorenal outcomes seen with SGLT2i therapy.NEW & NOTEWORTHY The physiological underpinnings of the cardiovascular benefits of SGLT2 inhibitors remain uncertain. We tested whether empagliflozin mitigates vascular insulin resistance in patients with type 2 diabetes. Aortic and peripheral systolic, diastolic, mean and pulse pressures, endothelial function, vascular stiffness, and heart and muscle microvascular perfusion were measured before and during an insulin infusion at baseline and after 12 wk of empagliflozin. After empagliflozin, vascular responses to insulin improved dramatically.
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Affiliation(s)
- Linda A Jahn
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - Lee M Hartline
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - Thi Nguyen
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - Kevin Aylor
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - William B Horton
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - Zhenqi Liu
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
| | - Eugene J Barrett
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
- Department of Pharmacology, University of Virginia, School of Medicine, Charlottesville, Virginia, United States
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Jahn LA, Hartline L, Liu Z, Barrett EJ. Metformin improves skeletal muscle microvascular insulin resistance in metabolic syndrome. Am J Physiol Endocrinol Metab 2022; 322:E173-E180. [PMID: 34957859 PMCID: PMC8858665 DOI: 10.1152/ajpendo.00287.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 12/16/2021] [Accepted: 12/20/2021] [Indexed: 11/22/2022]
Abstract
Microvascular insulin resistance is present in metabolic syndrome and may contribute to increased cardiovascular disease risk and the impaired metabolic response to insulin observed. Metformin improves metabolic insulin resistance in humans. Its effects on macro and microvascular insulin resistance have not been defined. Eleven subjects with nondiabetic metabolic syndrome were studied four times (before and after 12 wk of treatment with placebo or metformin) using a crossover design, with an 8-wk washout interval between treatments. On each occasion, we measured three indices of large artery function [pulse wave velocity (PWV), radial pulse wave separation analysis (PWSA), brachial artery endothelial function (flow-mediated dilation-FMD)] as well as muscle microvascular perfusion [contrast-enhanced ultrasound (CEU)] before and at 120 min into a 150 min, 1 mU/min/kg euglycemic insulin clamp. Metformin decreased body mass index (BMI), fat weight, and % body fat (P < 0.05, each), however, placebo had no effect. Metformin (not placebo) improved metabolic insulin sensitivity, (clamp glucose infusion rate, P < 0.01), PWV, and FMD after insulin were unaffected by metformin treatment. PWSA improved with insulin only after metformin P < 0.01). Insulin decreased muscle microvascular blood volume measured by contrast ultrasound both before and after placebo and before metformin (P < 0.02 for each) but not after metformin. Short-term metformin treatment improves both metabolic and muscle microvascular response to insulin. Metformin's effect on microvascular insulin responsiveness may contribute to its beneficial metabolic effects. Metformin did not improve aortic stiffness or brachial artery endothelial function, but enhanced radial pulse wave properties consistent with relaxation of smaller arterioles.NEW & NOTEWORTHY Metformin, a first-line treatment for type 2 diabetes, is often used in patients with insulin resistance and metabolic syndrome. Here, we provide the first evidence for metformin improving muscle microvascular insulin sensitivity in insulin-resistant humans. Simultaneously, metformin improved muscle glucose disposal, supporting a close relationship between insulin's microvascular and its metabolic actions in muscle. Whether enhanced microvascular insulin sensitivity contributes to metformin's ability to decrease microvascular complications in diabetes remains to be resolved.
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Affiliation(s)
- Linda A Jahn
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
| | - Lee Hartline
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
| | - Zhenqi Liu
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
| | - Eugene J Barrett
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
- Department of Pharmacology, University of Virginia, School of Medicine, Charlottesville, Virginia
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Stoner L, Barone Gibbs B, Meyer ML, Fryer S, Credeur D, Paterson C, Stone K, Hanson ED, Kowalsky RJ, Horiuchi M, Mack CP, Dave G. A Primer on Repeated Sitting Exposure and the Cardiovascular System: Considerations for Study Design, Analysis, Interpretation, and Translation. Front Cardiovasc Med 2021; 8:716938. [PMID: 34485414 PMCID: PMC8415972 DOI: 10.3389/fcvm.2021.716938] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/16/2021] [Indexed: 11/24/2022] Open
Abstract
Sedentary behavior, particularly sitting, is ubiquitous in many contemporary societies. This is a major societal concern considering the evidence for a strong association between sitting behavior and cardiovascular disease morbidity and mortality. Unsurprisingly, leading public health agencies have begun to advocate “reduction” in sitting behavior. Though, the guidelines are typically vague and non-specific. The lack of specific guidelines for prolonged sitting is attributable to the absence of available evidence to facilitate guideline development. To inform policy, well-designed randomized controlled trials are required to test the efficacy of specific and translatable sitting reduction strategies. To guide the design of randomized controlled trials, this review postulates that several gaps in the literature first need to be filled. Following a general discussion of the importance of sitting behavior to contemporary societies, each of the following are discussed: (i) acute sitting exposure and systems physiology; (ii) recommendations for a systems physiology toolbox; (iii) study design considerations for acute sitting exposure; and (iv) translation of sitting-focused research.
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Affiliation(s)
- Lee Stoner
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Bethany Barone Gibbs
- Department of Health and Human Development and Clinical and Translational Science, University of Pittsburgh, Pittsburgh, PA, United States
| | - Michelle L Meyer
- Department of Emergency Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Simon Fryer
- School of Sport and Exercise, University of Gloucestershire, Gloucester, United Kingdom
| | - Daniel Credeur
- Department of Biology, Ave Maria University, Ave Maria, FL, United States
| | - Craig Paterson
- School of Sport and Exercise, University of Gloucestershire, Gloucester, United Kingdom
| | - Keeron Stone
- School of Sport and Exercise, University of Gloucestershire, Gloucester, United Kingdom
| | - Erik D Hanson
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Robert J Kowalsky
- Department of Health and Kinesiology, Texas A&M University-Kingsville, Kingsville, TX, United States
| | - Masahiro Horiuchi
- Division of Human Environmental Science, Mount Fuji Research Institute, Yamanashi, Japan
| | - Christopher P Mack
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Gaurav Dave
- Division of General Medicine and Clinical Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Abdolhosseini P, Lark S, Wadsworth D, Stoner L. The Effects of Acute Bouts of Whole Body Vibration on Central Hemodynamics in Frail Older Adults: A Pilot Study. PHYSICAL & OCCUPATIONAL THERAPY IN GERIATRICS 2019. [DOI: 10.1080/02703181.2019.1622621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Sally Lark
- School of Sport, Exercise and Nutrition, Massey University, Wellington, New Zealand
| | - Daniel Wadsworth
- School of Sport, Exercise and Nutrition, Massey University, Wellington, New Zealand
- School of Nursing, Midwifery and Paramedicine, University of the Sunshine Coast, Australia
| | - Lee Stoner
- Department of Exercise and Sport Science, University of North Carolina, 209 Fetzer Hall, Chapel Hill, NC, USA
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Cardiorespiratory fitness predicts cardiovascular health in breast cancer survivors, independent of body composition, age and time post-treatment completion. Breast Cancer 2019; 26:729-737. [PMID: 31087274 DOI: 10.1007/s12282-019-00975-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/06/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND Breast cancer treatment may increase non-cancer related mortality risk due to unintended cardiovascular consequences. The aim of this study was to investigate the strongest correlate of cardiovascular health (CVH) in female breast cancer survivors, cardiorespiratory fitness or fatness. METHODS Fifty-one women (59 ± 9 years, BMI 26.4 ± 4.8 kg/m2) previously diagnosed and treated for primary breast cancer were assessed using pulse wave analysis to determine central arterial wave reflection (augmentation index, AIx) and central systolic blood pressure (cSBP). A composite Z score calculated which incorporated central double product and AIx, as an indicator of CVH. Dual energy X-ray absorptiometry was used to obtain total body fat percentage (BF%). Cardiorespiratory fitness was determined using the single-stage walk test to predict maximal oxygen uptake ([Formula: see text]). RESULTS Linear regression analysis revealed that fitness was associated with AIx after adjusting for BF %, age and time post-treatment completion (β = - 0.271, p = 0.010). A significant association between BF% and AIx after adjusting for fitness and age was found (β = 0.166, p = 0.0005); however, this association was lost when time post-treatment was included in the model (β = 0.166, p = 0.167). Both fitness (β = - 0.347, p = 0.0005) and BF% (β = 0.333, p = 0.013) were independently associated with CVH in the fully adjusted model. CONCLUSIONS This study provides evidence for an association between cardiorespiratory fitness and cardiovascular health in female breast cancer survivors. While fatness may be associated with cardiovascular health, it appears to be more strongly associated with age.
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Stoner L, Stone K, Zieff G, Hanson ED, Credeur D, Faulkner J, Kucharska-Newton A, Fryer S. The impact of upper-limb position on estimated central blood pressure waveforms. J Hum Hypertens 2019; 33:444-453. [PMID: 30804459 DOI: 10.1038/s41371-019-0179-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 01/25/2019] [Accepted: 02/08/2019] [Indexed: 11/09/2022]
Abstract
Pulse wave analysis (PWA) utilizes arm blood pressure (BP) waveforms to estimate aortic waveforms. The accuracy of central BP waveform estimation may be influenced by assessment site local haemodynamics. This study investigated whether local haemodynamic changes, induced via arm tilting ±30° relative to heart level, affect estimated central systolic BP (cSBP) and arterial wave reflection (central augmentation index, cAIx; aortic backward pressure wave, Pb). In 20 healthy adults (26.7 years [SD 5.2], 10 F) brachial BP waveforms were simultaneously recorded on experimental and control arms. The experimental arm was randomly repositioned three times (heart level, -30° heart level, +30° heart level), while the control arm remained fixed at heart level. For the experimental arm, arm repositioning resulted in a large (partial eta-squared > 0.14) effect size (ES) change in SBP (ES = 0.75, P < 0.001), cSBP (ES = 0.81, P < 0.001), and cAIx (ES = 0.75, P = 0.002), but not Pb (ES = 0.06, P = 0.38). In the control arm, cAIx (ES = 0.22, P = 0.013) but not SBP or cSBP significantly changed. Change in experimental arm cSBP was partially explained by brachial systolic blood velocity (P = 0.026) and mean diameter (P = 0.012), while change in cAIx was associated with brachial retrograde blood velocity (P = 0.020) and beta stiffness (P = 0.038). In conclusion, manipulation of assessment site local haemodynamics, including the blood velocity profile and local arterial stiffness, had a large effect on estimated cSBP and cAIx, but not on Pb. These findings do not invalidate PWA devices but do suggest that the accuracy of the estimated aortic pressure waveform is dependent on stable peripheral haemodynamics.
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Affiliation(s)
- Lee Stoner
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Keeron Stone
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
| | - Gabriel Zieff
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - EriK D Hanson
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Daniel Credeur
- School of Kinesiology, University of Southern Mississippi, Hattiesburg, MS, USA
| | - James Faulkner
- Department of Sport & Exercise, University of Winchester, Winchester, UK
| | - Anna Kucharska-Newton
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Simon Fryer
- School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
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Mitchelmore A, Stoner L, Lambrick D, Sykes L, Eglinton C, Jobson S, Faulkner J. Oscillometric central blood pressure and central systolic loading in stroke patients: Short-term reproducibility and effects of posture and fasting state. PLoS One 2018; 13:e0206329. [PMID: 30383781 PMCID: PMC6211701 DOI: 10.1371/journal.pone.0206329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/05/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND This study examined the short-term reproducibility of non-invasive estimates of central and peripheral blood pressure and markers of central systolic loading (augmentation index [AIx; a measure of central systolic loading] and AIx75 [AIx standardised to 75 b·min-1 heart rate]) and the effect of posture and fasting state on these variables in patients with acute stroke. METHODS Twenty-two acute stroke patients (72 ± 10y) had blood pressure measured using the SphygmoCor XCEL in supine and seated postures and whilst fasted and non-fasted. RESULTS Acceptable short-term reproducibility (ICC >0.75) was reported for all peripheral and central variables in all conditions (ICC = 0.77-0.90) and for AIx and AIx75 in both fasted postures (ICC = 0.78-0.81). Food consumption significantly lowered all blood pressures (p <0.05; η2p = 0.20-0.55). The seated posture resulted in a significantly greater AIx than supine (p <0.05; η2p = 0.22). Fasting state had significant main effects on AIx and AIx75 (p <0.05; η2p = 0.14-0.22). CONSLUSIONS Oscillometric estimates of central blood pressure have high short-term reproducibility in different postures and fasting states but markers of systolic load should be assessed whilst fasted. Fasting state has a large effect on central and peripheral blood pressures and on measures of systolic loading. It is important for clinicians to be aware of optimal assessment conditions without this impacting on patient wellbeing. TRIAL REGISTRATION Clinical trial registry name: NCT02537652.
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Affiliation(s)
- Andrew Mitchelmore
- Department of Sport, Exercise and Health, University of Winchester, Winchester, United Kingdom
| | - Lee Stoner
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Danielle Lambrick
- Faculty of Health Sciences, University of Southampton, Southampton, United Kingdom
| | - Lucy Sykes
- Hyper-Acute Stroke Unit, Hampshire Hospitals Foundation NHS Trust, Winchester, United Kingdom
| | - Charlotte Eglinton
- Hyper-Acute Stroke Unit, Hampshire Hospitals Foundation NHS Trust, Winchester, United Kingdom
| | - Simon Jobson
- Department of Sport, Exercise and Health, University of Winchester, Winchester, United Kingdom
| | - James Faulkner
- Department of Sport, Exercise and Health, University of Winchester, Winchester, United Kingdom
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Pierce DR, Doma K, Raiff H, Golledge J, Leicht AS. Influence of Exercise Mode on Post-exercise Arterial Stiffness and Pressure Wave Measures in Healthy Adult Males. Front Physiol 2018; 9:1468. [PMID: 30459633 PMCID: PMC6232940 DOI: 10.3389/fphys.2018.01468] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/28/2018] [Indexed: 12/14/2022] Open
Abstract
Background: Exercise mode has been reported to be an important determinant of arterial stiffness and wave reflection changes following a brief bout of exercise with inconsistent results to date. This study examined the impact of exercise mode on arterial stiffness and pressure wave measures following acute aerobic exercise (AER), resistance exercise (RES), and a control (CON) condition with no exercise. Methods: In a randomized, cross-over, repeated measures design, 21 healthy adult males (26.7 ± 7.2 years) undertook three experimental intervention sessions: AER (30-min cycle ergometry at 70-75% maximum heart rate), RES (3 × 10 repetitions of six upper and lower body exercises at 80-90% of 10-repetition maximum) and CON (30-min seated rest). Measures of arterial stiffness and pressure waves, such as carotid-femoral pulse wave velocity (cf-PWV), augmentation index (AIx), AIx corrected for heart rate of 75 (AIx75), and forward wave (Pf), backward wave (Pb) and reflection magnitude, were assessed at Rest and at 10-min intervals for 60 min after the intervention sessions. Comparisons between interventions and over time were assessed via repeated measures ANOVA and post-hoc Tukey's tests. Results: No significant differences in cf-PWV were noted between the three interventions at rest or post-intervention. However, RES led to significantly greater post-intervention AIx, AIx75, Pf, and Pb compared to AER and CON with AIx75 also remaining significantly elevated throughout the post-intervention period. In contrast, AER resulted in a brief, significant elevation of AIx75 and no change in cf-PWV, Pf, Pb, and reflection magnitude. Conclusions: Exercise mode, specifically RES and AER, significantly influenced the time course of pressure wave reflection responses following a brief bout of exercise in healthy adult males. Distinct adjustments during exercise including changes in blood pressure and vasomotor tone may be key modulators of post-exercise arterial function. Identification of modal differences may assist in understanding the impact of exercise on cardiovascular function and the mechanisms by which exercise benefits vascular health.
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Affiliation(s)
- Doris R Pierce
- Sport & Exercise Science, James Cook University, Cairns, QLD, Australia
| | - Kenji Doma
- Sport & Exercise Science, James Cook University, Townsville, QLD, Australia
| | - Hayleigh Raiff
- Department of Health and Sport Science, University of Dayton, Dayton, OH, United States
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, James Cook University, Townsville, QLD, Australia.,Department of Vascular and Endovascular Surgery, The Townsville Hospital, Townsville, QLD, Australia
| | - Anthony S Leicht
- Sport & Exercise Science, James Cook University, Townsville, QLD, Australia
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Perissiou M, Bailey TG, Windsor M, Leicht AS, Golledge J, Askew CD. Reliability of arterial stiffness indices at rest and following a single bout of moderate-intensity exercise in older adults. Clin Physiol Funct Imaging 2018; 39:42-50. [PMID: 29956874 DOI: 10.1111/cpf.12537] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 06/06/2018] [Indexed: 12/22/2022]
Abstract
Short-term changes in arterial stiffness with exercise are proposed to better reflect vascular impairments than resting measures alone and are suggested as a prognostic indicator of cardiovascular risk in older adults. Arterial stiffness indices are reliable at rest, but the time-course and reliability of postexercise changes in arterial stiffness in older adults are unknown. The precision of postexercise changes in arterial stiffness should be determined prior to their use in large prospective trials. This study assessed the between-day reliability of the changes in pulse wave velocity (PWV), augmentation index (AIx75) and reflection magnitude (RM) following an exercise bout in older adults. Ten older adults (71 ± 5 years) were tested on three separate days, 7 days apart. PWV, AIx75 and RM were assessed at rest, immediately post and at 20, 40 and 60 min during recovery after moderate-intensity cycling. Intraclass correlation coefficient (ICC) and reliability coefficient (RC) were used to assess the relative and absolute reliability of arterial stiffness responses. PWV increased, and RM decreased immediately after exercise (P<0·05), and returned to baseline during recovery. AIx decreased during recovery (P<0·001). Resting ICC values were 0·91 (PWV), 0·72 (AIx75) and 0·40 (RM). Reliability of the immediate changes following exercise was high for PWV (ICC:0·87, RC:1·9 m s-1 ) and moderate for AIx75 (ICC:0·64, RC:7%) and RM (ICC:0·59, RC:9%). Reliability of the postexercise responses was similar to that at rest for all measures of arterial stiffness. These findings indicate that postexercise changes in arterial stiffness indices are reliable in healthy older adults and supports further investigation of the prognostic value of these responses.
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Affiliation(s)
- Maria Perissiou
- VasoActive Research Group, School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia
| | - Tom G Bailey
- VasoActive Research Group, School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia.,Centre for Research on Exercise, Physical Activity and Health, School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
| | - Mark Windsor
- VasoActive Research Group, School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia
| | - Anthony S Leicht
- Sport and Exercise Science, James Cook University, Townsville, Queensland, Australia
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, James Cook University, Townsville, Queensland, Australia.,Department of Vascular and Endovascular Surgery, The Townsville Hospital, Townsville, Queensland, Australia
| | - Christopher D Askew
- VasoActive Research Group, School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore, Australia
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Reliability of pulse waveform separation analysis responses to an orthostatic challenge. Hypertens Res 2018; 41:176-182. [PMID: 29335614 DOI: 10.1038/s41440-017-0005-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/17/2017] [Accepted: 08/04/2017] [Indexed: 11/08/2022]
Abstract
Cardiovascular autonomic nervous system function can be assessed using an orthostatic challenge to induce arterial wave reflection. While arterial reflection is typically estimated using a central augmentation index, a superior estimation can be obtained using pulse wave separation analysis to estimate the aortic backward pressure wave (Pb). However, to be of value in a clinical or research setting, an assessment tool must be precise (reliable). Therefore, this study sought to determine the measurement precision of Pb responses to a modified tilt-table test. Twenty healthy adults (26.4 year (SD 5.2), 24.7 kg/m2 (SD 3.8), 55% female) were tested in a fasted state on three different mornings separated by a maximum of seven days. Pressure waveforms were recorded on the left arm, and aortic waveforms were generated using a generalized transfer function. Subsequently, a physiologic flow waveform was assumed to separate the aortic pressure wave into its forward and timing-independent backward (Pb) components. The criterion intra-class correlation coefficient of ≥0.75 was exceeded at baseline (0.79), following a 5-min tilt (0.75), and following a 5-min recovery from tilt (0.75). The standard error of measurement was 7%. These findings indicate that in a healthy cohort, the Pb response to an orthostatic challenge can be assessed with acceptable precision. The next step is to determine the sensitivity (validity) of this technique in identifying cardiovascular autonomic dysfunction in patient groups.
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11
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Reliability of oscillometric central blood pressure responses to lower limb resistance exercise. Atherosclerosis 2018; 268:157-162. [DOI: 10.1016/j.atherosclerosis.2017.11.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/21/2017] [Accepted: 11/30/2017] [Indexed: 11/21/2022]
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