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Smith PJ, Sherwood A, Hinderliter AL, Mabe S, Watkins LL, Craighead L, Ingle K, Tyson C, Avorgbedor F, Lin PH, Kraus WE, Liao L, Blumenthal JA. Lifestyle modification and cognitive function among individuals with resistant hypertension: cognitive outcomes from the TRIUMPH trial. J Hypertens 2022; 40:1359-68. [PMID: 35703293 DOI: 10.1097/HJH.0000000000003151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Resistant hypertension is associated with increased risk of cognitive decline, stroke, and dementia. Lifestyle modification has been suggested to improve cognitive function through its salutary effects on vascular function. METHODS Participants included 140 patients with resistant hypertension participating in the TRIUMPH trial. Participants were randomized to a cardiac rehabilitation-based lifestyle program (C-LIFE) or a standardized education and physician advice condition (SEPA). Participants completed a 45-min cognitive test battery consisting of tests of Executive Functioning and Learning, Memory, and Processing Speed. Biomarkers of vascular [flow mediated dilation of the brachial artery (FMD)], microvascular, and cerebrovascular function were also collected, in addition to weight, fitness, and ambulatory blood pressure. RESULTS Participants averaged 63 years of age, 48% women, 59% black, and obese [mean BMI = 36 kg/m 2 (SD = 4)]. Cognitive performance improved across the entire cohort during the 4-month trial [ t -scores pretreatment = 48.9 (48, 50) vs. posttreatment = 50.0 (49, 51), P < 0.001]. Postintervention Executive Function/Learning composite performance was higher for participants in C-LIFE compared to SEPA ( d = 0.37, P = 0.039). C-LIFE intervention effects on Memory and Processing Speed were moderated by sex and baseline stroke risk, respectively ( P = 0.026 and P = 0.043 for interactions), such that males and participants with greater stroke risk showed the greatest cognitive changes. FMD [C-LIFE: +0.3% (-0.3, 1.0) vs. SEPA: -1.4% (-2.5, -0.3), P = 0.022], and microvascular function [C-LIFE: 97 (65, 130) vs. SEPA: 025 (-75, 23), P < 0.001] were improved in C-LIFE compared with SEPA, whereas cerebrovascular reactivity was not [C-LIFE: -0.2 (-0.4, 0) vs. SEPA: 0.1 (-0.2, 0.4), P = 0.197). Mediation analyses suggested that increased executive function/learning was associated with reduced ambulatory SBP levels secondary to weight loss [indirect effect: B = 0.25 (0.03, 0.71)]. CONCLUSION Lifestyle modification individuals with resistant hypertension improves cognition, which appeared to be associated with reduced ambulatory SBP changes through weight loss. Cognitive improvements were accompanied by parallel improvements in endothelial and microvascular function.
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Smith PJ, Sherwood A, Hinderliter AL, Mabe S, Tyson C, Avorgbedor F, Watkins LL, Lin PH, Kraus WE, Blumenthal JA. Cerebrovascular Function, Vascular Risk, and Lifestyle Patterns in Resistant Hypertension. J Alzheimers Dis 2022; 87:345-357. [PMID: 35275539 DOI: 10.3233/jad-215522] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Impaired cerebrovascular reactivity (CVR) and blunted cerebral hemodynamic recruitment are thought to be important mechanisms linking hypertension to cerebrovascular and cognitive outcomes. Few studies have examined cardiovascular or dietary correlates of CVR among hypertensives. OBJECTIVE To delineate associations between cardiometabolic risk, diet, and cerebrovascular functioning among individuals with resistant hypertension from the TRIUMPH trial (n = 140). METHODS CVR was assessed by examining changes in tissue oxygenation (tissue oxygenation index [TOI] and oxygenated hemoglobin [HBO2]) using functional near-infrared spectroscopy (fNIRS) during a breath holding test, a standardized CVR assessment to elicit a hypercapnic response. Participants also underwent fNIRS during three cognitive challenge tasks. Vascular function was assessed by measurement of brachial artery flow mediated dilation and hyperemic flow response. Cardiometabolic fitness was assessed from peak VO2 on an exercise treadmill test and body mass index. Dietary patterns were quantified using the DASH eating score. Cognitive function was assessed using a 45-minute test battery assessing Executive Function, Processing Speed, and Memory. RESULTS Greater levels fitness (B = 0.30, p = 0.011), DASH compliance (B = 0.19, p = 0.045), and lower obesity (B = -0.30, p = 0.004), associated with greater changes in TOI, whereas greater flow-mediated dilation (B = 0.19, p = 0.031) and lower stroke risk (B = -0.19, p = 0.049) associated with greater HBO2. Similar associations were found for cerebral hemodynamic recruitment, and associations between CVR and cognition were moderated by duration of hypertension. CONCLUSION Impaired CVR elevated cardiometabolic risk, obesity, vascular function, and fitness among hypertensives.
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Affiliation(s)
- Patrick J Smith
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Andrew Sherwood
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Alan L Hinderliter
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Stephanie Mabe
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Crystal Tyson
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Forgive Avorgbedor
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Lana L Watkins
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
| | - Pao-Hwa Lin
- Department of Medicine and Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, USA
| | - William E Kraus
- Department of Medicine and Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, USA
| | - James A Blumenthal
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
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Senzaki K, Okada Y, Ochi H, Ochi M, Takei SI, Miura S, Igase M, Ohyagi Y. Vascular endothelial dysfunction associated with severity in multiple sclerosis. Mult Scler Relat Disord 2021; 54:103135. [PMID: 34274738 DOI: 10.1016/j.msard.2021.103135] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Impairment of cerebrovascular reactivity (CVR) has been reported in patients with multiple sclerosis (MS). Chronic inflammation and endothelial dysfunction are possible mechanisms underlying this hemodynamic impairment. This study aimed to evaluate CVR and endothelial function in patients with MS and explore their relationships with disease progression using functional sonographic procedures. METHODS Patients with MS and age-/sex-matched healthy controls were assessed for endothelial function, determined by flow-mediated dilation (FMD), and CVR, measured using the breath-holding index (BHI). RESULTS Twenty-seven patients with MS and 24 healthy controls were enrolled. FMD was significantly lower in MS subjects than in control subjects (6.0 ± 0.6 vs. 8.6 ± 0.7, p = 0.006); furthermore, BHI was similarly lower in MS than in controls, but insignificant. Remarkably, FMD was significantly lower in secondary progressive MS subjects than in relapse-remitting MS subjects (3.7 ± 1.3 vs. 6.7 ± 0.7, p = 0.045). In addition, FMD was inversely correlated with the disability score as per the expanded disability status scale (R2 = 0.170, p = 0.033) and modified Rankin scale (R2 = 0.187, p = 0.027). CONCLUSION In patients with MS, endothelial dysfunction was more noticeable than CVR impairment, correlating with the severity and progression of MS.
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Li N, Liu Y, Zhao Y, Wu X, Tong J, Hua Y. Cerebrovascular reactivity in young and old patients with obstructive sleep apnea. Sleep Med 2020; 73:125-129. [PMID: 32827884 DOI: 10.1016/j.sleep.2020.04.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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] [Received: 12/02/2019] [Revised: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Impaired cerebrovascular reactivity (CVR) in patients with obstructive sleep apnea syndrome (OSAS) increases the risk of ischemic stroke. CVR also decreases with age in normal individuals. However, it is unclear whether OSAS affects CVR differently in young and old patients. The aim of this study was to compare CVR in old and young patients with OSAS via transcranial Doppler (TCD) measurements of changes in cerebral blood flow velocity in the middle cerebral artery (MCAmv) during breath holding and hyperventilation. METHODS A total of 20 old patients (≥65 y) and 40 young patients (<65 y) with similar distributions of sex and OSAS severity were recruited for this study. The breath-holding index (BHI) and the hyperventilation index (HVI) were calculated to measure CVR. RESULTS No differences were found in MCAmv at baseline, apnea or hyperventilation between the two groups with different OSAS severities. However, reduced BHI (P < 0.01) and HVI (P < 0.01) were found in the young group with increasing severity of OSAS. Notably, the decline in BHI and HVI associated with OSAS severity was steeper in young patients than in old patients (P < 0.01). CONCLUSIONS These findings suggest that CVR in young patients is more impacted by OSAS severity than that in old patients, suggesting the existence of age-related cerebrovascular susceptibility to OSAS.
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Affiliation(s)
- Na Li
- Department of Vascular Ultrasonography, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Yumei Liu
- Department of Vascular Ultrasonography, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China; Center of Vascular Ultrasonography, Beijing Institute of Brain Disorders, Beijing, 100053 China
| | - Ying Zhao
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Xiaoguang Wu
- Evidence-based Medicine Center, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Junyao Tong
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China
| | - Yang Hua
- Department of Vascular Ultrasonography, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China; Center of Vascular Ultrasonography, Beijing Institute of Brain Disorders, Beijing, 100053 China.
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Zhao XN, Song HP, Yang F, Wu DJ, Gong WQ, Zhang Y, Sun X, Zheng MJ. Ultrasonic Characteristics of Cardiovascular Changes in Children with Hutchinson-Gilford Progeria Syndrome: A Comparative Study with Normal Children and Aging People. Biomed Res Int 2020; 2020:9631851. [PMID: 32382582 DOI: 10.1155/2020/9631851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 02/15/2020] [Indexed: 11/25/2022]
Abstract
Background The cardiovascular characteristics of children with Hutchinson-Gilford progeria syndrome (HGPS) remain unclear. The present study is aimed at evaluating the cardiovascular changes with ultrasound examination in children with HGPS and compared these with those in normal children and older people. Methods Seven HGPS children, 21 age-matched healthy children, and 14 older healthy volunteers were evaluated by three-dimensional echocardiography (including strain analysis) and carotid elasticity examination with the echo-tracking technique. Results Children with HGPS had higher left ventricular ejection fraction (LVEF) and global longitudinal strain, when compared to older healthy volunteers (P < 0.05). However, these parameters were not significantly different, when compared to those in healthy children. Furthermore, children with HGPS had lower average peak times in the left ventricle, when compared with the other two groups. For the structure of the carotid artery detected by ultrasound, the abnormality rates were similar between children with HGPS and older healthy volunteers (83.3% vs. 71.4%). The elastic parameters, elastic modulus, stiffness parameter, and pulsed wave transmittal velocity of children with HGPS were lower, when compared to those in older healthy volunteers (P < 0.05), while they were higher with arterial compliance (P > 0.05). Furthermore, no significant difference existed among the vascular elastic parameters between HGPS and normal children. Conclusion HGPS children had impaired left ventricular (LV) synchrony, when compared to normal children, although the difference in LVEF was not statistically significant. Furthermore, the structural abnormality of the carotid artery in HGPS children was similar to that in older people, although the index of elasticity appears to be more favorable. These results suggest that the cardiovascular system in HGPS children differs from natural aging.
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Hussein A, Matthews JL, Syme C, Macgowan C, MacIntosh BJ, Shirzadi Z, Pausova Z, Paus T, Chen JJ. The association between resting-state functional magnetic resonance imaging and aortic pulse-wave velocity in healthy adults. Hum Brain Mapp 2020; 41:2121-2135. [PMID: 32034832 PMCID: PMC7268071 DOI: 10.1002/hbm.24934] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [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: 10/09/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 12/11/2022] Open
Abstract
Resting‐state functional magnetic resonance imaging (rs‐fMRI) is frequently used to study brain function; but, it is unclear whether BOLD‐signal fluctuation amplitude and functional connectivity are associated with vascular factors, and how vascular‐health factors are reflected in rs‐fMRI metrics in the healthy population. As arterial stiffening is a known age‐related cardiovascular risk factor, we investigated the associations between aortic stiffening (as measured using pulse‐wave velocity [PWV]) and rs‐fMRI metrics. We used cardiac MRI to measure aortic PWV (an established indicator of whole‐body vascular stiffness), as well as dual‐echo pseudo‐continuous arterial‐spin labeling to measure BOLD and CBF dynamics simultaneously in a group of generally healthy adults. We found that: (1) higher aortic PWV is associated with lower variance in the resting‐state BOLD signal; (2) higher PWV is also associated with lower BOLD‐based resting‐state functional connectivity; (3) regions showing lower connectivity do not fully overlap with those showing lower BOLD variance with higher PWV; (4) CBF signal variance is a significant mediator of the above findings, only when averaged across regions‐of‐interest. Furthermore, we found no significant association between BOLD signal variance and systolic blood pressure, which is also a known predictor of vascular stiffness. Age‐related vascular stiffness, as measured by PWV, provides a unique scenario to demonstrate the extent of vascular bias in rs‐fMRI signal fluctuations and functional connectivity. These findings suggest that a substantial portion of age‐related rs‐fMRI differences may be driven by vascular effects rather than directly by brain function.
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Affiliation(s)
- Ahmad Hussein
- Rotman Research Institute, Baycrest Health Sciences, Toronto, Canada
| | - Jacob L Matthews
- Rotman Research Institute, Baycrest Health Sciences, Toronto, Canada
| | - Catriona Syme
- SickKids Hospital, Toronto, Canada.,Department of Physiology, University of Toronto, Toronto, Canada
| | - Christopher Macgowan
- SickKids Hospital, Toronto, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Bradley J MacIntosh
- Department of Medical Biophysics, University of Toronto, Toronto, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada
| | - Zahra Shirzadi
- Department of Medical Biophysics, University of Toronto, Toronto, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada
| | - Zdenka Pausova
- SickKids Hospital, Toronto, Canada.,Department of Physiology, University of Toronto, Toronto, Canada
| | - Tomáš Paus
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Canada.,Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Canada
| | - J Jean Chen
- Rotman Research Institute, Baycrest Health Sciences, Toronto, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Canada
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Torjesen A, Cooper LL, Rong J, Larson MG, Hamburg NM, Levy D, Benjamin EJ, Vasan RS, Mitchell GF. Relations of Arterial Stiffness With Postural Change in Mean Arterial Pressure in Middle-Aged Adults: The Framingham Heart Study. Hypertension 2017; 69:685-690. [PMID: 28264924 DOI: 10.1161/hypertensionaha.116.08116] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [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: 07/04/2016] [Revised: 07/20/2016] [Accepted: 01/29/2017] [Indexed: 11/16/2022]
Abstract
Impaired regulation of blood pressure on standing can lead to adverse outcomes, including falls, syncope, and disorientation. Mean arterial pressure (MAP) typically increases on standing; however, an insufficient increase or a decline in MAP on standing may result in decreased cerebral perfusion. Orthostatic hypotension has been reported in older people with increased arterial stiffness, whereas the association between orthostatic change in MAP and arterial stiffness in young- to middle-aged individuals has not been examined. We analyzed orthostatic blood pressure response and comprehensive hemodynamic data in 3205 participants (1693 [53%] women) in the Framingham Heart Study Third Generation cohort. Participants were predominantly middle aged (mean age: 46±9 years). Arterial stiffness was assessed using carotid-femoral pulse wave velocity, forward pressure wave amplitude, and characteristic impedance of the aorta. Adjusting for standard cardiovascular disease risk factors, orthostatic change in MAP (6.9±7.7 mm Hg) was inversely associated with carotid-femoral pulse wave velocity (partial correlation, rp=-0.084; P<0.0001), forward wave amplitude (rp=-0.129; P<0.0001), and characteristic impedance (rp=-0.094; P<0.0001). The negative relation between forward wave amplitude and change in MAP on standing was accentuated in women (P=0.002 for sex interaction). Thus, higher aortic stiffness was associated with a blunted orthostatic increase in MAP, even in middle age. The clinical implications of these findings warrant further study.
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Affiliation(s)
- Alyssa Torjesen
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Leroy L Cooper
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Jian Rong
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Martin G Larson
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Naomi M Hamburg
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Daniel Levy
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Emelia J Benjamin
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Ramachandran S Vasan
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.)
| | - Gary F Mitchell
- From the Cardiovascular Engineering, Inc, Norwood, MA (A.T., L.L.C., G.F.M.); Cardiovascular Research Center, Rhode Island Hospital, W. Alpert Medical School of Brown University, Providence (L.L.C.); National Heart, Lung, and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA (J.R., M.G.L., D.L., E.J.B., R.S.V.); Department of Biostatistics, Boston University School of Public Health, MA (M.G.L.); Evans Department of Medicine (N.M.H., E.J.B., R.S.V.), Whitaker Cardiovascular Institute (N.M.H., E.J.B., R.S.V.), and Preventive Medicine and Cardiology Sections (E.J.B., R.S.V.), Boston University School of Medicine, MA; and National Heart, Lung, and Blood Institute, Bethesda, MD (D.L.).
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Melnikov VN, Divert VE, Komlyagina TG, Consedine NS, Krivoschekov SG. Baseline values of cardiovascular and respiratory parameters predict response to acute hypoxia in young healthy men. Physiol Res 2017; 66:467-479. [PMID: 28248531 DOI: 10.33549/physiolres.933328] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The majority of the available works have studied distinct hypoxic responses of respiratory and cardiovascular systems. This study examines how these systems interact while responding to hypoxia and whether baseline metrics moderate reactions to a hypoxic challenge. Central hemodynamic, aortic wave reflection, and gas exchange parameters were measured in 27 trained young men before and after 10-min normobaric isocapnic hypoxia (10 % O2). Associations were assessed by correlation and multiple regression analyses. Hypoxic changes in the parameters of pulse wave analysis such as augmentation index (-114 %, p=0.007), pulse pressure amplification (+6 %, p=0.020), time to aortic reflection wave (+21 %, p<0.001) report on the increase in arterial distensibility. Specifically, initially compliant arteries blunt the positive cardiac chronotropic response to hypoxia and facilitate the myocardial workload. The degree of blood oxygen desaturation is directly correlated with both baseline values and hypoxic responses of aortic and peripheral blood pressures. The hypoxia-induced gain in ventilation (VE), while controlling for basal VE and heart rate (HR), is inversely associated with deltaHR and deltasystolic blood pressure. The study suggests that cardiovascular and respiratory systems mutually supplement each other when responding to hypoxic challenge.
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Affiliation(s)
- V N Melnikov
- Institute of Physiology and Basic Medicine, Novosibirsk, Russia.
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Malojcic B, Giannakopoulos P, Sorond FA, Azevedo E, Diomedi M, Oblak JP, Carraro N, Boban M, Olah L, Schreiber SJ, Pavlovic A, Garami Z, Bornstein NM, Rosengarten B. Ultrasound and dynamic functional imaging in vascular cognitive impairment and Alzheimer's disease. BMC Med 2017; 15:27. [PMID: 28178960 PMCID: PMC5299782 DOI: 10.1186/s12916-017-0799-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/21/2017] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND The vascular contributions to neurodegeneration and neuroinflammation may be assessed by magnetic resonance imaging (MRI) and ultrasonography (US). This review summarises the methodology for these widely available, safe and relatively low cost tools and analyses recent work highlighting their potential utility as biomarkers for differentiating subtypes of cognitive impairment and dementia, tracking disease progression and evaluating response to treatment in various neurocognitive disorders. METHODS At the 9th International Congress on Vascular Dementia (Ljubljana, Slovenia, October 2015) a writing group of experts was formed to review the evidence on the utility of US and arterial spin labelling (ASL) as neurophysiological markers of normal ageing, vascular cognitive impairment (VCI) and Alzheimer's disease (AD). Original articles, systematic literature reviews, guidelines and expert opinions published until September 2016 were critically analysed to summarise existing evidence, indicate gaps in current knowledge and, when appropriate, suggest standards of use for the most widely used US and ASL applications. RESULTS Cerebral hypoperfusion has been linked to cognitive decline either as a risk or an aggravating factor. Hypoperfusion as a consequence of microangiopathy, macroangiopathy or cardiac dysfunction can promote or accelerate neurodegeneration, blood-brain barrier disruption and neuroinflammation. US can evaluate the cerebrovascular tree for pathological structure and functional changes contributing to cerebral hypoperfusion. Microvascular pathology and hypoperfusion at the level of capillaries and small arterioles can also be assessed by ASL, an MRI signal. Despite increasing evidence supporting the utility of these methods in detection of microvascular pathology, cerebral hypoperfusion, neurovascular unit dysfunction and, most importantly, disease progression, incomplete standardisation and missing validated cut-off values limit their use in daily routine. CONCLUSIONS US and ASL are promising tools with excellent temporal resolution, which will have a significant impact on our understanding of the vascular contributions to VCI and AD and may also be relevant for assessing future prevention and therapeutic strategies for these conditions. Our work provides recommendations regarding the use of non-invasive imaging techniques to investigate the functional consequences of vascular burden in dementia.
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Affiliation(s)
- Branko Malojcic
- Department of Neurology, University Hospital Center Zagreb, Zagreb School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia.
| | | | - Farzaneh A Sorond
- Department of Neurology, Northwestern University Feinberg School of Medicine Chicago, Chicago, IL, USA
| | - Elsa Azevedo
- Department of Neurology, São João Hospital Center and Faculty of Medicine of University of Porto, Porto, Portugal
| | - Marina Diomedi
- Cerebrovascular Disease Center, Stroke Unit, University of Rome Tor Vergata, Rome, Italy
| | - Janja Pretnar Oblak
- Department of Vascular Neurology and Intensive Therapy, University Medical Center Ljubljana, Ljubljana, Slovenia
| | - Nicola Carraro
- Department of Medical Sciences, Clinical Neurology-Stroke Unit, University Hospital, University of Trieste, Trieste, Italy
| | - Marina Boban
- Department of Neurology, University Hospital Center Zagreb, Zagreb School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia
| | - Laszlo Olah
- Department of Neurology, University of Debrecen, Debrecen, Hungary
| | - Stephan J Schreiber
- Department of Neurology, Charite - Universitätsmedizin Berlin, Berlin, Germany
| | - Aleksandra Pavlovic
- Neurology Clinic, Clinical Center of Serbia, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Zsolt Garami
- Methodist DeBakey Heart and Vascular Center, Houston, TX, USA
| | - Nantan M Bornstein
- Neurology Department, Tel Aviv Sourasky Medical Centre, Tel Aviv, Israel
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10
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Tan CH, Low KA, Schneider-Garces N, Zimmerman B, Fletcher MA, Maclin EL, Chiarelli AM, Gratton G, Fabiani M. Optical measures of changes in cerebral vascular tone during voluntary breath holding and a Sternberg memory task. Biol Psychol 2016; 118:184-194. [PMID: 27235126 PMCID: PMC9906974 DOI: 10.1016/j.biopsycho.2016.05.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 05/20/2016] [Accepted: 05/20/2016] [Indexed: 12/24/2022]
Abstract
The human cerebral vasculature responds to changes in blood pressure and demands for oxygenation via cerebral autoregulation. Changes in cerebrovascular tone (vasoconstriction and vasodilation) also mediate the changes in blood flow measured by the BOLD fMRI signal. This cerebrovascular reactivity is known to vary with age. In two experiments, we demonstrate that cerebral pulse parameters measured using optical imaging can quantify changes in cerebral vascular tone, both globally and locally. In experiment 1, 51 older adults (age range=55-87) performed a voluntary breath-holding task while cerebral pulse amplitude measures were taken. We found significant pulse amplitude variations across breath-holding periods, indicating vasodilation during, and vasoconstriction after breath holding. The breath-holding index (BHI), a measure of cerebrovascular reactivity (CVR) was derived and found to correlate with age. BHI was also correlated with performance in the Modified Mini-Mental Status Examination, even after controlling for age and education. In experiment 2, the same participants performed a Sternberg task, and changes in regional pulse amplitude between high (set-size 6) and low (set-size 2) task loads were compared. Only task-related areas in the fronto-parietal network (FPN) showed significant reduction in pulse amplitude, indicating vasodilation. Non-task-related areas such as the somatosensory and auditory cortices did not show such reductions. Taken together, these experiments suggest that optical pulse parameters can index changes in brain vascular tone both globally and locally, using both physiological and cognitive load manipulations.
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Affiliation(s)
- Chin Hong Tan
- Department of Psychology, University of Illinois at Urbana-Champaign, United States,Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | - Kathy A. Low
- Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | | | - Benjamin Zimmerman
- Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | - Mark A. Fletcher
- Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | - Edward L. Maclin
- Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | | | - Gabriele Gratton
- Department of Psychology, University of Illinois at Urbana-Champaign, United States,Beckman Institute, University of Illinois at Urbana-Champaign, United States
| | - Monica Fabiani
- Department of Psychology, University of Illinois at Urbana-Champaign, United States; Beckman Institute, University of Illinois at Urbana-Champaign, United States.
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11
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Haratz S, Weinstein G, Molshazki N, Beeri MS, Ravona-Springer R, Marzeliak O, Goldbourt U, Tanne D. Impaired Cerebral Hemodynamics and Cognitive Performance in Patients with Atherothrombotic Disease. J Alzheimers Dis 2016; 46:137-44. [PMID: 25720410 DOI: 10.3233/jad-150052] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [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: 01/23/2023]
Abstract
BACKGROUND AND OBJECTIVE Patients with pre-existing atherothrombotic disease are prone to cognitive impairment. We tested whether impaired cerebrovascular reactivity (CVR), a marker of cerebral microvascular hemodynamic dysfunction, is associated with poorer cognitive scores among patients with and without carotid large-vessel disease. METHODS A subgroup of non-demented patients with chronic coronary heart disease followed-up for 15 ± 3 years was assessed for cognitive function (Neurotrax Computerized Cognitive Battery; scaled to an IQ style scale with a mean of 100 and SD of 15) and for CVR using the breath-holding index (BHI) with transcranial Doppler and for carotid plaques using ultrasound. We assessed cognitive scores in specific domains in patients with and without impaired CVR (BHI <0.47; bottom quartile). RESULTS Among 415 patients (mean age 71.7 ± 6.2 y) median BHI was 0.73 (25% 0.47, 75% 1.04). Impaired CVR was associated with diabetes and peripheral artery disease. Adjusting for potential confounders, impaired CVR was associated with lower executive function (p = 0.02) and global cognitive scores (p = 0.04). There was an interaction with carotid large-vessel disease for executive function (p < 0.001), memory (p = 0.03), and global cognitive scores (p = 0.02). In the carotid large-vessel disease group there were pronounced differences by CVR status in executive function (p < 0.001), memory (p = 0.02), attention (p < 0.001), and global cognitive scores (p = 0.001). CONCLUSION Impaired CVR, a marker of cerebral microvascular dysfunction, is associated with poorer cognitive functions and in particular executive dysfunction among non-demented patients with concomitant carotid large-vessel disease. These findings emphasize the importance of cerebral hemodynamics in cognitive performance.
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Affiliation(s)
- Salo Haratz
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel.,Department of Neurology, Hospital das Clínicas, São Paulo University, São Paulo, Brazil
| | - Galit Weinstein
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Noa Molshazki
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Michal Schnaider Beeri
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel.,Department of Psychiatry at the Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Oleg Marzeliak
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel
| | - Uri Goldbourt
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - David Tanne
- The Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel.,Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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Rucka D, Marek J, Rucklova Z, Lubanda JC, Havranek S, Skvaril J, Varejka P, Chochola M, Karetova D, Korinek J, Linhart A. Arterial stiffening contributes to impairment of cerebrovascular reactivity in patients with coronary artery disease without carotid stenosis. Physiol Res 2014; 64:335-43. [PMID: 25536320 DOI: 10.33549/physiolres.932837] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Impaired cerebrovascular reactivity (CVR), an important risk factor for future stroke, is affected by a presence carotid stenosis. However, in some cases CVR can be impaired in the absence of carotid stenosis due to several poorly characterized mechanisms. We hypothesized that arterial stiffening as observed in coronary heart disease (CHD) could be associated with alteration in CVR in CHD patients without carotid stenosis. The study population consisted of patients referred for coronary angiography without significant carotid stenosis (<50 %). CVR was evaluated by breath holding index (BHI) measured with transcranial color code duplex ultrasound. Arterial stiffness was assessed by pulse wave velocity (PWV) measured by the oscillometric method. The extent of coronary atherosclerosis was quantified by Gensini score (GS). Out of 186 subjects, sixty-two patients fulfilled the inclusion and exclusion criteria. BHI decreased with increasing PWV (r = -0.47, p<0.001). Decrease in BHI was significantly inversely associated with GS (r = -0.61, p<0.001). GS was associated with PWV (p<0.001). In conclusion, impaired CVR was associated with increased arterial stiffening in CHD patients in the absence of significant carotid stenosis. Thus, we speculate that increased arterial stiffness may at least partially contribute to the pathophysiology of CVR alteration in coronary artery disease.
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Affiliation(s)
- D Rucka
- Second Department of Internal Medicine - Cardiology and Angiology, General University Hospital, First School of Medicine, Charles University, Prague, Czech Republic.
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Prakash K, Chandran DS, Khadgawat R, Jaryal AK, Deepak KK. Correction for blood pressure improves correlation between cerebrovascular reactivity assessed by breath holding and 6% CO(2) breathing. J Stroke Cerebrovasc Dis 2013; 23:630-5. [PMID: 23830954 DOI: 10.1016/j.jstrokecerebrovasdis.2013.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [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: 01/31/2013] [Revised: 05/28/2013] [Accepted: 06/03/2013] [Indexed: 10/26/2022] Open
Abstract
BACKGROUND Changes in cerebral blood flow velocity to hypercapnia are associated with changes in systemic blood pressure (BP). These confounding BP-dependent changes in cerebral blood flow velocity cause misinterpretation of cerebrovascular reactivity (CVR) results. The objective of the study was to determine the relationship between CVR assessed by breath holding and 6% CO2 breathing after correcting for BP-dependent changes in cerebral blood flow velocity. METHODS In 33 patients of uncomplicated type 2 diabetes mellitus, CVR was assessed as percentage changes in cerebral blood flow velocity and cerebrovascular conductance index. RESULTS Percentage change in cerebral blood flow velocity during breath holding was positively correlated with that of during 6% CO2 breathing (r = .35; P = .0448). CVR during breath holding and 6% CO2 breathing were better correlated when expressed as percentage changes in cerebrovascular conductance index (r = .49; P = .0040). Similarly, breath-holding test results expressed as percentage changes in cerebral blood flow velocity correctly identified only 37.5% of the poor reactors to 6% CO2 breathing. However, when the breath-holding test results were expressed as percentage changes in cerebrovascular conductance index, 62.5% of the poor reactors to 6% CO2 breathing were correctly identified indicating a better agreement between the test results obtained by the 2 methods. CONCLUSION Cerebrovascular response to breath holding is better correlated with that of 6% CO2 breathing when changes in cerebral blood flow velocity were corrected for associated changes in BP.
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Affiliation(s)
- Kiran Prakash
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - Dinu S Chandran
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
| | - Rajesh Khadgawat
- Department of Endocrinology and Metabolism, All India Institute of Medical Sciences, New Delhi, India
| | - Ashok Kumar Jaryal
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India.
| | - Kishore Kumar Deepak
- Department of Physiology, All India Institute of Medical Sciences, New Delhi, India
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14
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Vuletic V, Drenjancevic I, Rahelic D, Demarin V. Effect of indomethacin on cerebrovascular reactivity in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract 2013; 101:81-7. [PMID: 23684449 DOI: 10.1016/j.diabres.2013.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/21/2013] [Accepted: 04/22/2013] [Indexed: 10/26/2022]
Abstract
AIM Impaired cerebral vasoreactivity to endothelium-dependent stimuli were described in type 2 diabetes mellitus (T2DM), but the mechanisms underlying that impairment are still unclear. The aim of this study was to investigate the role of cyclooxygenases' metabolites in response to acute hypercapnic stimulus in cerebral vessels, in patients with T2DM. METHODS Vascular responses in the breath-holding test (BHT) were assessed in the absence/presence of a non-selective, reversible-inhibitor of cyclooxygenases, indomethacin (INDO), by functional transcranial Doppler sonography of the middle cerebral artery (N of patients=50; 33 men and 17 women). The functional hemodynamic parameter mean flow velocity (MFV) was assessed at rest, before and 90min after 100mg of INDO, and during the BHT. Breath holding index (BHI) [(MFV at the end of BHT minus MFV at rest)/MFV at rest)×100/s of breath-holding] was calculated after BHT performed before and 90min after INDO. RESULTS MFV at rest significantly decreased after INDO administration compared with a control condition before INDO (at rest before INDO from 49.36±15.09 to 36.72±8.45 after INDO, p<0.001) However, overall cerebral vessel vasoreactivity to hypercapnia, evaluated with BHI, was significantly improved after INDO administration compared with the BHI before INDO administration (from 0.68±0.4 to 1.27±0.42, p<0.001). CONCLUSIONS The improvement in cerebral vasoreactivity in response to BHT after INDO administration suggests that the production of a vasoconstrictor metabolite of cyclooxygenase in diabetic patients was reduced by indomethacin consumption.
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Affiliation(s)
- Vladimira Vuletic
- Department of Neurology, Dubrava University Hospital, Zagreb, Croatia.
| | - Ines Drenjancevic
- Department of Physiology and Immunology, Faculty of Medicine Osijek, University Josip, Juraj Strossmayer, Osijek, Croatia
| | - Dario Rahelic
- Department of Endocrinology, Diabetes and Metabolic Disorders, Dubrava University Hospital, Zagreb, Croatia
| | - Vida Demarin
- Medical Director, Medical Centre "Aviva", Zagreb, Croatia
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15
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Demarin V, Zavoreo I, Kes VB. Carotid artery disease and cognitive impairment. J Neurol Sci 2012; 322:107-11. [DOI: 10.1016/j.jns.2012.07.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 06/20/2012] [Accepted: 07/05/2012] [Indexed: 11/18/2022]
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Zavoreo I, Kes VB, Morović S, Šerić V, Demarin V. Breath holding index in detection of early cognitive decline. J Neurol Sci 2010; 299:116-9. [DOI: 10.1016/j.jns.2010.08.062] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 08/23/2010] [Accepted: 08/27/2010] [Indexed: 01/21/2023]
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