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Reddin C, Murphy R, Hankey GJ, Wang X, Langhorne P, Oveisgharan S, Xavier D, Judge C, Rosengren A, Iversen HK, Czlonkowska A, Lanas F, Oguz A, Ryglewicz D, Wasay M, Smyth A, Yusuf S, O'Donnell M. Blood pressure variability in acute stroke: Risk factors and association with functional outcomes at 1 month. Eur J Neurol 2024; 31:e16314. [PMID: 38738545 PMCID: PMC11235980 DOI: 10.1111/ene.16314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 05/14/2024]
Abstract
BACKGROUND AND PURPOSE Blood pressure variability, in acute stroke, may be an important modifiable determinant of functional outcome after stroke. In a large international cohort of participants with acute stroke, it was sought to determine the association of blood pressure variability (in the early period of admission) and functional outcomes, and to explore risk factors for increased blood pressure variability. PATIENTS AND METHODS INTERSTROKE is an international case-control study of risk factors for first acute stroke. Blood pressure was recorded at the time of admission, the morning after admission and the time of interview in cases (median time from admission 36.7 h). Multivariable ordinal regression analysis was employed to determine the association of blood pressure variability (standard deviation [SD] and coefficient of variance) with modified Rankin score at 1-month follow-up, and logistic regression was used to identify risk factors for blood pressure variability. RESULTS Amongst 13,206 participants, the mean age was 62.19 ± 13.58 years. When measured by SD, both systolic blood pressure variability (odds ratio 1.13; 95% confidence interval 1.03-1.24 for SD ≥20 mmHg) and diastolic blood pressure variability (odds ratio 1.15; 95% confidence interval 1.04-1.26 for SD ≥10 mmHg) were associated with a significant increase in the odds of poor functional outcome. The highest coefficient of variance category was not associated with a significant increase in risk of higher modified Rankin score at 1 month. Increasing age, female sex, high body mass index, history of hypertension, alcohol use, and high urinary potassium and low urinary sodium excretion were associated with increased blood pressure variability. CONCLUSION Increased blood pressure variability in acute stroke, measured by SD, is associated with an increased risk of poor functional outcome at 1 month. Potentially modifiable risk factors for increased blood pressure variability include low urinary sodium excretion.
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Affiliation(s)
- Catriona Reddin
- HRB Clinical Research Facility Galway, School of MedicineUniversity of GalwayGalwayIreland
- Wellcome Trust‐HRB, Irish Clinical Academic TrainingDublinIreland
| | - Robert Murphy
- HRB Clinical Research Facility Galway, School of MedicineUniversity of GalwayGalwayIreland
| | - Graeme J. Hankey
- Perron Institute Chair in Stroke Research, Medical SchoolUniversity of Western AustraliaPerthWestern AustraliaAustralia
- Perron Institute for Neurological and Translational SciencePerthWestern AustraliaAustralia
| | - Xingyu Wang
- Beijing Hypertension League InstituteBeijingChina
| | - Peter Langhorne
- Academic Section of Geriatric Medicine, Glasgow Royal InfirmaryUniversity of GlasgowGlasgowUK
| | - Shahram Oveisgharan
- Rush Alzheimer Disease Research CenterRush University Medical CenterChicagoIllinoisUSA
| | - Denis Xavier
- St Johns Medical CollegeBangaloreIndia
- St Johns Research InstituteBangaloreIndia
| | - Conor Judge
- HRB Clinical Research Facility Galway, School of MedicineUniversity of GalwayGalwayIreland
| | - Annika Rosengren
- Sahlgrenska University Hospital and Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Helle K. Iversen
- Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | | | - Fernando Lanas
- Faculty of MedicineUniversidad de La FronteraTemucoChile
| | - Aytekin Oguz
- Department of Internal Medicine, Faculty of MedicineIstanbul Medeniyet University, Dumlupinar MahallesiIstanbulTurkey
- Faculty of MedicineIstanbul Medeniyet UniversityIstanbulTurkey
| | | | - Mohammad Wasay
- Department of MedicineAga Khan UniversityKarachiPakistan
| | - Andrew Smyth
- HRB Clinical Research Facility Galway, School of MedicineUniversity of GalwayGalwayIreland
| | - Salim Yusuf
- Population Health Research InstituteHamilton Health Sciences and McMaster UniversityHamiltonOntarioCanada
| | - Martin O'Donnell
- HRB Clinical Research Facility Galway, School of MedicineUniversity of GalwayGalwayIreland
- Population Health Research InstituteHamilton Health Sciences and McMaster UniversityHamiltonOntarioCanada
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Abiri A, Chou EF, Shen W, Fisher MJ, Khine M. Changes in beat-to-beat blood pressure and pulse rate variability following stroke. Sci Rep 2023; 13:19245. [PMID: 37935766 PMCID: PMC10630489 DOI: 10.1038/s41598-023-45479-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 10/19/2023] [Indexed: 11/09/2023] Open
Abstract
Associations between cerebrovascular disease and impaired autonomic function and cerebrovascular reactivity have led to increased interest in variability of heart rate (HRV) and blood pressure (BPV) following stroke. In this study, beat-to-beat pulse rate variability (PRV) and BPV were measured in clinically stable stroke patients (6 ischemic, 2 hemorrhagic) at least one year after their last cerebrovascular event. Beat-to-beat blood pressure (BP) measurements were collected from subjects while resting in the sitting position for one hour. Compared with healthy controls, stroke patients exhibited significantly greater time-domain (standard deviation, coefficient of variation, average real variability) and normalized high-frequency BPV (all p < 0.05). Stroke patients also exhibited lower LF:HF ratios than control subjects (p = 0.003). No significant differences were observed in PRV between the two groups, suggesting that BPV may be a more sensitive biomarker of cerebrovascular function in long-term post-stroke patients. Given a paucity of existing literature investigating beat-to-beat BPV in clinically stable post-stroke patients long (> 1 year) after their cerebrovascular events, this pilot study can help inform future studies investigating the mechanisms and effects of BPV in stroke. Elucidating this physiology may facilitate long-term patient monitoring and pharmacological management to mitigate the risk for recurrent stroke.
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Affiliation(s)
- Arash Abiri
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA
| | - En-Fan Chou
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA
| | - Weining Shen
- Department of Statistics, University of California Irvine, Irvine, CA, USA
| | - Mark J Fisher
- Department of Neurology, Irvine Medical Center, University of California, Orange, CA, USA
| | - Michelle Khine
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, USA.
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O'Brien MW, Nardone M, Foster M, Coovadia Y, Usselman CW, Taylor CE, Millar PJ, Kimmerly DS. Higher sympathetic transduction is independently associated with greater very short-term diastolic blood pressure variability in young healthy males and females. Clin Auton Res 2023; 33:529-532. [PMID: 37243873 DOI: 10.1007/s10286-023-00949-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 04/29/2023] [Indexed: 05/29/2023]
Affiliation(s)
- Myles W O'Brien
- School of Physiotherapy (Faculty of Health) and Department of Medicine (Faculty of Medicine), Dalhousie University, Halifax, NS, Canada.
- Geriatric Medicine Research, Dalhousie University and Nova Scotia Health, Halifax, NS, Canada.
| | - Massimo Nardone
- Human Cardiovascular Physiology Laboratory, Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Monique Foster
- School of Health Sciences, Western Sydney University, Sydney, NSW, Australia
| | - Yasmine Coovadia
- Cardiovascular Health and Autonomic Regulation Laboratory, McGill University, Montreal, QC, Canada
| | - Charlotte W Usselman
- Cardiovascular Health and Autonomic Regulation Laboratory, McGill University, Montreal, QC, Canada
| | - Chloe E Taylor
- School of Health Sciences, Western Sydney University, Sydney, NSW, Australia
| | - Philip J Millar
- Human Cardiovascular Physiology Laboratory, Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Derek S Kimmerly
- Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, NS, Canada
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Abiri A, Chou EF, Qian C, Rinehart J, Khine M. Intra-beat biomarker for accurate continuous non-invasive blood pressure monitoring. Sci Rep 2022; 12:16772. [PMID: 36202815 PMCID: PMC9537243 DOI: 10.1038/s41598-022-19096-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/24/2022] [Indexed: 11/10/2022] Open
Abstract
Accurate continuous non-invasive blood pressure (CNIBP) monitoring is the holy grail of digital medicine but remains elusive largely due to significant drifts in signal and motion artifacts that necessitate frequent device recalibration. To address these challenges, we developed a unique approach by creating a novel intra-beat biomarker (Diastolic Transit Time, DTT) to achieve highly accurate blood pressure (BP) estimations. We demonstrated our approach’s superior performance, compared to other common signal processing techniques, in eliminating stochastic baseline wander, while maintaining signal integrity and measurement accuracy, even during significant hemodynamic changes. We applied this new algorithm to BP data collected using non-invasive sensors from a diverse cohort of high acuity patients and demonstrated that we could achieve close agreement with the gold standard invasive arterial line BP measurements, for up to 20 min without recalibration. We established our approach's generalizability by successfully applying it to pulse waveforms obtained from various sensors, including photoplethysmography and capacitive-based pressure sensors. Our algorithm also maintained signal integrity, enabling reliable assessments of BP variability. Moreover, our algorithm demonstrated tolerance to both low- and high-frequency motion artifacts during abrupt hand movements and prolonged periods of walking. Thus, our approach shows promise in constituting a necessary advance and can be applied to a wide range of wearable sensors for CNIBP monitoring in the ambulatory and inpatient settings.
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Affiliation(s)
- Arash Abiri
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, 92697, USA
| | - En-Fan Chou
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, 92697, USA
| | - Chengyang Qian
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, 92697, USA
| | - Joseph Rinehart
- Department of Anesthesiology & Perioperative Care, University of California, Irvine Medical Center, Orange, CA, USA
| | - Michelle Khine
- Department of Biomedical Engineering, University of California Irvine, Irvine, CA, 92697, USA.
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Webb AJS, Wartolowska KA, Li L, Mazzucco S, Rothwell PM. Consistencies and Differences in Intermediate Physiological Phenotypes of Vascular Ageing between Ischaemic Stroke Aetiologies. Cerebrovasc Dis 2022; 52:194-201. [PMID: 35998558 PMCID: PMC7615998 DOI: 10.1159/000525764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 03/24/2022] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Arterial stiffness, cerebral pulsatility, and beat-to-beat blood pressure variability partly mediate the relationship between hypertension and stroke, but it is unknown if these intermediate phenotypes of vascular ageing differ between stroke aetiologies. We therefore aimed to characterize differences in these intermediate cardiovascular phenotypes between patients presenting with strokes of different aetiologies. METHODS In consecutive patients on best medical management 1 month after TIA or nondisabling stroke (Oxford Vascular Study), arterial stiffness (PWV) was measured by applanation tonometry (Sphygmocor), middle cerebral blood flow velocity, and pulsatility index (MCA-PI) were measured by transcranial ultrasound (TCD, DWL Doppler Box), and beat-to-beat BP variability was measured with a Finometer. Differences between patients with large artery (LAS), small vessel (SVD), cardioembolic (CE), or undetermined events were derived, including adjustment for cardiovascular risk factors. Relationships were characterized by mixed linear models. RESULTS In 909 eligible patients, MCA-PI, PWV, and SBPV were all positively skewed. Mean values were greatest in LAS than CE and lowest in SVD (p < 0.001). However, after adjustment for age, sex, and risk factors, PI was greatest in LAS and lowest in CE stroke, whilst PWV was greatest in SVD and undetermined stroke (p < 0.001). In multivariate linear models, age was more strongly associated with PWV and PI in patients with small vessel stroke than other aetiologies, particularly under the age of 65, but SBPV was only weakly associated with demographic indices in all stroke subtypes. CONCLUSIONS Intermediate cardiovascular phenotypes of vascular ageing had similar demographic associations between stroke aetiologies, but these were particularly strong in patients with small vessel stroke under the age of 65, implying a potential role of these phenotypes in increasing stroke risk in this patient group.
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Affiliation(s)
| | | | - Linxin Li
- Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK
| | - Sara Mazzucco
- Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK
| | - Peter M Rothwell
- Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK
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Asmuje NF, Mat S, Myint PK, Tan MP. Blood Pressure Variability and Cognitive Function: a Scoping Review. Curr Hypertens Rep 2022; 24:375-383. [PMID: 35731334 DOI: 10.1007/s11906-022-01200-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE OF REVIEW To conduct a scoping review of articles which have evaluated BPV and cognitive function. Articles with keywords, titles or abstracts containing the terms 'cognitive' OR 'cognition' OR 'dementia' AND 'blood pressure variability' were identified from CINAHL, Medline, PMC and Web of Science. RECENT FINDINGS Methods of acquisition and analysis of BPV and cognitive measurements and their relationship were extracted from selected articles. Of 656 studies identified, 53 articles were selected. Twenty-five evaluated long-term (LTBPV), nine mid-term (MTBPV), 12 short-term (STBPV) and nine very short-term BPV (VSTBPV) with conflicting findings on the relationship between BPV and cognition. Variations existed in devices, period and procedure for acquisition. The studies also utilized a wide range of methods of BPV calculation. Thirteen cognitive assessment tools were used to measure global cognition or domain functions which were influenced by the population of interest. The interpretation of available studies was hence limited by heterogeneity. There is an urgent need for standardization of BPV assessments to streamline research on BPV and cognition. Future studies should also establish whether BPV could be a potential modifiable risk factor for cognitive decline, as well as a marker for treatment response.
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Affiliation(s)
- Nur Fazidah Asmuje
- Kolej Genius Insan, Universiti Sains Islam Malaysia, Negeri Sembilan, Malaysia. .,Ageing and Age-Associated Disorders Research Group, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Sumaiyah Mat
- Physiotherapy Programme and Center of Healthy Ageing and Wellness, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - Phyo Kyaw Myint
- Ageing Clinical & Experimental Research (ACER) Team, Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, UK.,Department of Medicine for the Elderly, NHS Grampian, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Maw Pin Tan
- Ageing and Age-Associated Disorders Research Group, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. .,Centre for Innovations in Medical Engineering, University of Malaya, Kuala Lumpur, Malaysia. .,Department of Medical Sciences, Faculty of Healthcare and Medical Sciences, Sunway University, Bandar Sunway, Malaysia.
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Webb AJ, Lawson A, Wartolowska K, Mazzucco S, Rothwell PM. Aortic Stiffness, Pulse Pressure, and Cerebral Pulsatility Progress Despite Best Medical Management: The OXVASC Cohort. Stroke 2022; 53:1310-1317. [PMID: 34852644 PMCID: PMC7612543 DOI: 10.1161/strokeaha.121.035560] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/26/2021] [Accepted: 10/06/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. METHODS In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), arterial stiffness (pulse wave velocity [PWV]) and aortic systolic, aortic diastolic, and aortic pulse pressures (aoPP) were measured by applanation tonometry (Sphygmocor), while middle cerebral artery (MCA) peak (MCA-PSV) and trough (MCA-EDV) flow velocity and Gosling pulsatility index (PI; MCA-PI) were measured by transcranial ultrasound (transcranial Doppler, DWL Doppler Box). Repeat assessments were performed at the 5-year follow-up visit after intensive medical treatment and agreement determined by intraclass correlation coefficients. Rates of progression and their determinants, stratified by age and sex, were determined by mixed-effects linear models, adjusted for age, sex, and cardiovascular risk factors. RESULTS In 188 surviving, eligible patients with repeat assessments after a median of 5.8 years. PWV, aoPP, and MCA-PI were highly reproducible (intraclass correlation coefficients, 0.71, 0.59, and 0.65, respectively), with progression of PWV (2.4%; P<0.0001) and aoPP (3.5%; P<0.0001) but not significantly for MCA-PI overall (0.93; P=0.22). However, PWV increased at a faster rate with increasing age (0.009 m/s per y/y; P<0.0001), while aoPP and MCA-PI increased significantly above the age of 55 years (aoPP, P<0.0001; MCA-PI, P=0.009). Higher aortic systolic blood pressure and diastolic blood pressure predicted a greater rate of progression of PWV and aoPP, but not MCA-PI, although current MCA-PI was particularly strongly associated with concurrent aoPP (P<0.001). CONCLUSIONS Arterial pulsatility and aortic stiffness progressed significantly after 55 years of age despite the best medical treatment. Progression of stiffness and aoPP was determined by high blood pressure, but MCA-PI predominantly reflected current aoPP. Treatments targetting cerebral pulsatility may need to principally target aortic stiffness and pulse pressure to have the potential to prevent cerebral small vessel disease.
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Affiliation(s)
- Alastair J.S. Webb
- Department of Clinical Neurosciences, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, United Kingdom
| | - Amy Lawson
- Department of Clinical Neurosciences, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, United Kingdom
| | - Karolina Wartolowska
- Department of Clinical Neurosciences, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, United Kingdom
| | - Sara Mazzucco
- Department of Clinical Neurosciences, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, United Kingdom
| | - Peter M. Rothwell
- Department of Clinical Neurosciences, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, United Kingdom
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Lee YK, Mazzucco S, Rothwell PM, Payne SJ, Webb AJS. Blood Pressure Complexity Discriminates Pathological Beat-to-Beat Variability as a Marker of Vascular Aging. J Am Heart Assoc 2022; 11:e022865. [PMID: 35043657 PMCID: PMC9238484 DOI: 10.1161/jaha.121.022865] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Background Beat‐to‐beat blood pressure variability (BPV) is associated with an increased risk of stroke but can be driven by both healthy physiological processes and failure of compensatory mechanisms. Blood pressure (BP) complexity measures structured, organized variations in BP, as opposed to random fluctuations, and its reduction may therefore identify pathological beat‐to‐beat BPV. Methods and Results In the prospective, population‐based OXVASC (Oxford Vascular Study) Phenotyped Cohort with transient ischemic attack or minor stroke, patients underwent at least 5 minutes of noninvasive beat‐to‐beat monitoring of BP (Finometer) and ECG to derive the following: BPV (coefficient of variation) and complexity (modified multiscale entropy) of systolic BP and diastolic BP, heart rate variability (SD of R‐R intervals), and baroreflex sensitivity (BRS; Welch's method), in low‐ (0.04–0.15 Hz) and high‐frequency (0.15–0.4 Hz) bands. Associations between BPV or BP complexity with autonomic indexes and arterial stiffness were determined (linear regression), unadjusted, and adjusted for age, sex, and cardiovascular risk factors. In 908 consecutive, consenting patients, BP complexity was inversely correlated with BPV coefficient of variation (P<0.001) and was similarly reduced in patients with hypertension or diabetes (P<0.001). However, although BPV coefficient of variation had a U‐shaped relationship with age, BP complexity fell systematically across age quintiles (quintile 1: 15.1 [14.0–16.1] versus quintile 5: 13.8 [12.4–15.1]) and was correlated with markers of autonomic dysfunction (heart rate variability SD of R‐R intervals: r = 0.20; BRS low frequency: 0.19; BRS high frequency: 0.26) and arterial stiffness (pulse wave velocity: −0.21; all P<0.001), even after adjustment for clinical variables (heart rate variability SD of R‐R intervals: 0.12; BRS low frequency and BRS high frequency: 0.13 and 0.17; and pulse wave velocity: −0.07; all P<0.05). Conclusions Loss of BP complexity discriminates BPV because of pathological failure of compensatory mechanisms and may represent a less confounded and potentially modifiable risk factor for stroke.
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Affiliation(s)
- Yun-Kai Lee
- Institute of Biomedical Engineering Department of Engineering Science University of Oxford UK
| | - Sara Mazzucco
- Wolfson Centre for Prevention of Stroke and DementiaNuffield Department of Clinical NeurosciencesJohn Radcliffe HospitalUniversity of Oxford UK
| | - Peter M Rothwell
- Wolfson Centre for Prevention of Stroke and DementiaNuffield Department of Clinical NeurosciencesJohn Radcliffe HospitalUniversity of Oxford UK
| | - Stephen J Payne
- Institute of Biomedical Engineering Department of Engineering Science University of Oxford UK
| | - Alastair J S Webb
- Wolfson Centre for Prevention of Stroke and DementiaNuffield Department of Clinical NeurosciencesJohn Radcliffe HospitalUniversity of Oxford UK
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