1
|
Gronewold J, Jokisch M, Schramm S, Jockwitz C, Miller T, Lehmann N, Moebus S, Jöckel KH, Erbel R, Caspers S, Hermann DM. Association of Blood Pressure, Its Treatment, and Treatment Efficacy With Volume of White Matter Hyperintensities in the Population-Based 1000BRAINS Study. Hypertension 2021; 78:1490-1501. [PMID: 34628935 DOI: 10.1161/hypertensionaha.121.18135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Janine Gronewold
- Department of Neurology, University Hospital Essen, Germany (J.G., M.J., D.M.H.)
| | - Martha Jokisch
- Department of Neurology, University Hospital Essen, Germany (J.G., M.J., D.M.H.)
| | - Sara Schramm
- Institute for Medical Informatics, Biometry and Epidemiology (S.S., N.L., K.-H.J., R.E.), University Hospital Essen, University Duisburg-Essen, Germany
| | - Christiane Jockwitz
- Institute of Neuroscience and Medicine, Research Centre Jülich, Germany (C.J., T.M., S.C.).,Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Germany (C.J., T.M., S.C.)
| | - Tatiana Miller
- Institute of Neuroscience and Medicine, Research Centre Jülich, Germany (C.J., T.M., S.C.).,Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Germany (C.J., T.M., S.C.)
| | - Nils Lehmann
- Institute for Medical Informatics, Biometry and Epidemiology (S.S., N.L., K.-H.J., R.E.), University Hospital Essen, University Duisburg-Essen, Germany
| | - Susanne Moebus
- Centre for Urban Epidemiology, Institute for Medical Informatics, Biometry and Epidemiology (S.M.), University Hospital Essen, University Duisburg-Essen, Germany
| | - Karl-Heinz Jöckel
- Institute for Medical Informatics, Biometry and Epidemiology (S.S., N.L., K.-H.J., R.E.), University Hospital Essen, University Duisburg-Essen, Germany
| | - Raimund Erbel
- Institute for Medical Informatics, Biometry and Epidemiology (S.S., N.L., K.-H.J., R.E.), University Hospital Essen, University Duisburg-Essen, Germany
| | - Svenja Caspers
- Institute of Neuroscience and Medicine, Research Centre Jülich, Germany (C.J., T.M., S.C.).,Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University, Germany (C.J., T.M., S.C.)
| | - Dirk M Hermann
- Department of Neurology, University Hospital Essen, Germany (J.G., M.J., D.M.H.)
| | | |
Collapse
|
2
|
Leong SL, Robertson IH, Lawlor B, Vanneste S. Associations between Hypertension, Treatment, and Cognitive Function in the Irish Longitudinal Study on Ageing. J Clin Med 2020; 9:jcm9113735. [PMID: 33233792 PMCID: PMC7699900 DOI: 10.3390/jcm9113735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 11/18/2022] Open
Abstract
Epidemiological studies have produced conflicting results regarding the associations between the use of different hypertensive drugs and cognition. Data from the Irish Longitudinal Study on Ageing (TILDA), a nationwide prospective longitudinal study of adults aged 50 or more years, was used to explore the associations between hypertensive status, categories of antihypertensive and cognitive function controlling for age, education, and other demographic and lifestyle factors. The study sample included 8173 participants. ANCOVAs and multivariate regressions were used to assess the cross-sectional and longitudinal associations between cognitive function and hypertension status and the different categories of hypertensive medication. Hypertension was not associated with decline in global cognitive and executive functions and were fully explained by age and education. Different hypertensive medications were not associated with cognitive function. Consistent with previous studies, changes in cognition can largely be explained by age and education. The use of antihypertensive medications is neither harmful nor protective for cognition.
Collapse
Affiliation(s)
- Sook Ling Leong
- Global Brain Health Institute & Trinity Institute of Neuroscience, Trinity College Dublin, DO2 PN40 Dublin, Ireland; (S.L.L.); (I.H.R.); (B.L.)
- School of Psychology, Trinity College Dublin, DO2 PN40 Dublin, Ireland
| | - Ian H. Robertson
- Global Brain Health Institute & Trinity Institute of Neuroscience, Trinity College Dublin, DO2 PN40 Dublin, Ireland; (S.L.L.); (I.H.R.); (B.L.)
| | - Brian Lawlor
- Global Brain Health Institute & Trinity Institute of Neuroscience, Trinity College Dublin, DO2 PN40 Dublin, Ireland; (S.L.L.); (I.H.R.); (B.L.)
| | - Sven Vanneste
- Global Brain Health Institute & Trinity Institute of Neuroscience, Trinity College Dublin, DO2 PN40 Dublin, Ireland; (S.L.L.); (I.H.R.); (B.L.)
- School of Psychology, Trinity College Dublin, DO2 PN40 Dublin, Ireland
- Correspondence:
| |
Collapse
|
3
|
Zhuang S, Wang HF, Wang X, Li J, Xing CM. The association of renin-angiotensin system blockade use with the risks of cognitive impairment of aging and Alzheimer's disease: A meta-analysis. J Clin Neurosci 2016; 33:32-38. [PMID: 27475317 DOI: 10.1016/j.jocn.2016.02.036] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/08/2016] [Accepted: 02/14/2016] [Indexed: 10/21/2022]
Abstract
A quantitative meta-analysis was performed to evaluate the association of renin-angiotensin system blockade (RASB) use with the incidence of cognitive impairment of aging and Alzheimer's disease (AD). Pubmed, Embase, and Cochrane Library databases were searched up to October 2015. Ten studies that assessed the relationship between RASB use and the incidence of cognitive impairment of aging or AD were included. When randomized trials and observational studies were combined, the use of RASB was significantly associated with a reduced risk of AD (risk ratio [RR], 0.80; 95% confidence interval [CI] 0.68-0.92) and cognitive impairment of aging (RR, 0.65; 95% CI 0.35-0.94) compared no use of RASB. Meanwhile, in an analysis of subgroups, both subjects with angiotensin converting enzyme inhibitor (ACEI) and angiotensin receptor blocker (ARB) use were lower incidence of AD (RR, 0.87; 95% CI 0.74-1.00; RR, 0.69; 95% CI 0.44-0.93, respectively) than those without, whereas, indirect comparison between ACEI and ARB revealed no significance in the risk of AD (RR, 1.27, 95% CI 0.85-1.89, p=0.245). In an analysis of cognitive impairment of aging, ARB use (RR, 0.40; 95% CI 0.02-0.78), rather than ACEI use (RR, 0.72; 95% CI 0.36-1.09), was shown to decrease the risk of cognitive impairment of aging. In conclusion, RASB treatments, regardless of the drug class, have benefits on prevention of AD, and the effects of ACEI may analogous to ARB. However, the benefit differs according to drug classes for cognitive impairment of aging, with ARB use, rather than ACEI use, being a potential treatment for reducing the incidence of cognitive impairment of aging.
Collapse
Affiliation(s)
- Shan Zhuang
- Department of Neurology, Longkou People's Hospital, Longkou, Yantai, Shandong Province, China; Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, No.5 Donghai Middle Road, Qingdao, Shandong Province, China
| | - Hai-Feng Wang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, No.5 Donghai Middle Road, Qingdao, Shandong Province, China
| | - Xin Wang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, No.5 Donghai Middle Road, Qingdao, Shandong Province, China
| | - Jun Li
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, No.5 Donghai Middle Road, Qingdao, Shandong Province, China
| | - Cheng-Ming Xing
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, No.5 Donghai Middle Road, Qingdao, Shandong Province, China.
| |
Collapse
|
4
|
Manso-Calderón R, González-Sarmiento R. Genetic susceptibility to vascular cognitive impairment: a pathophysiological view. FUTURE NEUROLOGY 2016. [DOI: 10.2217/fnl-2016-0002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The heterogeneity of the vascular cognitive impairment (VCI) creates challenges for research on its genetic basis and pathophysiology. Despite well-known monogenic forms may be useful to understand some pathogenic mechanisms leading to VCI, most of VCIs are sporadic disorders resulting from the interaction between environmental, vascular and genetic factors. Genetic investigation for VCI may encompass both candidate genes that affect critical biological processes to VCI and common and rare genetic variants identified across the entire genome study technology, thereby enabling us to confirm or expose new biological mechanisms in VCI and develop new therapeutic and preventive approaches. Notwithstanding genetic susceptibility to VCI remains largely unknown owing to methodological issues. Collaborative efforts emerge as an interesting strategy to overcome these problems.
Collapse
Affiliation(s)
- Raquel Manso-Calderón
- Department of Neurology, University Hospital of Salamanca, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca-CSIC-SACYL, Salamanca, Spain
| | - Rogelio González-Sarmiento
- Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca-CSIC-SACYL, Salamanca, Spain
- Molecular Medicine Unit, Department of Medicine & Institute of Molecular & Cellular Biology of Cancer (IBMCC). University of Salamanca-CSIC, Salamanca, Spain
| |
Collapse
|
5
|
Schuch JB, Constantin PC, da Silva VK, Korb C, Bamberg DP, da Rocha TJ, Fiegenbaum M, de Oliveira A, Tisser LA, de Andrade FM. ACE polymorphism and use of ACE inhibitors: effects on memory performance. AGE (DORDRECHT, NETHERLANDS) 2014; 36:9646. [PMID: 24696269 PMCID: PMC4082601 DOI: 10.1007/s11357-014-9646-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 03/18/2014] [Indexed: 05/19/2023]
Abstract
Memory is an important cognition function, being fundamental to the development and independence of individuals. Our aim was to investigate the influence apolipoprotein E (APOE) and angiotensin I-converting enzyme (ACE) polymorphism and ACE inhibitors use, besides their interaction on memory performance of healthy subjects over 50 years. The sample consisted of 205 subjects assessed for five types of episodic memory, using Wechsler Memory Scale-Revised (WMS-R), who answered a questionnaire about drug use and were assessed for the ACE insertion/deletion polymorphism and APOE polymorphism. We found no influence of the APOE gene. The use of ACE inhibitors beneficially influenced learning ability scores (p = 0.02). Besides, I allele carriers of ACE polymorphism showed higher verbal memory scores compared with homozygous DD. Also, we observed an interaction influencing learning ability between the ACE polymorphism and the use of inhibitors, the beneficial influence of the I allele was present only in individuals who make use of ACE inhibitors. We conclude that the ACE gene has influence on memory performance, and that this influence is modulated by ACE inhibitors use.
Collapse
Affiliation(s)
- Jaqueline B. Schuch
- />Institute of Health Sciences, Universidade Feevale, Novo Hamburgo, RS Brazil
| | | | - Vanessa K. da Silva
- />Institute of Health Sciences, Universidade Feevale, Novo Hamburgo, RS Brazil
| | - Camila Korb
- />Institute of Health Sciences, Universidade Feevale, Novo Hamburgo, RS Brazil
| | - Daiani P. Bamberg
- />Institute of Human Sciences, Letters and Arts, Universidade Feevale, Novo Hamburgo, RS Brazil
| | - Tatiane J. da Rocha
- />Basic Health Sciences Department, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Rio Grande do Sul Brazil
| | - Marilu Fiegenbaum
- />Basic Health Sciences Department, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Rio Grande do Sul Brazil
| | - Alcyr de Oliveira
- />Psychology Department, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Rio Grande do Sul Brazil
| | - Luciana A. Tisser
- />Institute of Human Sciences, Letters and Arts, Universidade Feevale, Novo Hamburgo, RS Brazil
| | - Fabiana M. de Andrade
- />Institute of Health Sciences, Universidade Feevale, Novo Hamburgo, RS Brazil
- />Institute of Human Sciences, Letters and Arts, Universidade Feevale, Novo Hamburgo, RS Brazil
- />Pró-Reitoria de Pesquisa e Inovação – PROPI, sala 201 F, Universidade Feevale, RS 239, no. 2755, Novo Hamburgo, RS 93352-000 Brazil
| |
Collapse
|
6
|
Naffah-Mazzacoratti MDG, Gouveia TLF, Simões PSR, Perosa SR. What have we learned about the kallikrein-kinin and renin-angiotensin systems in neurological disorders? World J Biol Chem 2014; 5:130-140. [PMID: 24921004 PMCID: PMC4050108 DOI: 10.4331/wjbc.v5.i2.130] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 02/10/2014] [Accepted: 03/18/2014] [Indexed: 02/05/2023] Open
Abstract
The kallikrein-kinin system (KKS) is an intricate endogenous pathway involved in several physiological and pathological cascades in the brain. Due to the pathological effects of kinins in blood vessels and tissues, their formation and degradation are tightly controlled. Their components have been related to several central nervous system diseases such as stroke, Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, epilepsy and others. Bradykinin and its receptors (B1R and B2R) may have a role in the pathophysiology of certain central nervous system diseases. It has been suggested that kinin B1R is up-regulated in pathological conditions and has a neurodegenerative pattern, while kinin B2R is constitutive and can act as a neuroprotective factor in many neurological conditions. The renin angiotensin system (RAS) is an important blood pressure regulator and controls both sodium and water intake. AngII is a potent vasoconstrictor molecule and angiotensin converting enzyme is the major enzyme responsible for its release. AngII acts mainly on the AT1 receptor, with involvement in several systemic and neurological disorders. Brain RAS has been associated with physiological pathways, but is also associated with brain disorders. This review describes topics relating to the involvement of both systems in several forms of brain dysfunction and indicates components of the KKS and RAS that have been used as targets in several pharmacological approaches.
Collapse
|
7
|
Marmarelis VZ, Shin DC, Orme ME, Zhang R. Model-based quantification of cerebral hemodynamics as a physiomarker for Alzheimer's disease? Ann Biomed Eng 2013; 41:2296-317. [PMID: 23771298 PMCID: PMC3992829 DOI: 10.1007/s10439-013-0837-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 05/29/2013] [Indexed: 01/27/2023]
Abstract
Previous studies have found that Alzheimer's disease (AD) impairs cerebral vascular function, even at early stages of the disease. This offers the prospect of a useful diagnostic method for AD, if cerebral vascular dysfunction can be quantified reliably within practical clinical constraints. We present a recently developed methodology that utilizes a data-based dynamic nonlinear closed-loop model of cerebral hemodynamics to compute "physiomarkers" quantifying the state of cerebral flow autoregulation to pressure-changes (CA) and cerebral CO2 vasomotor reactivity (CVMR) in each subject. This model is estimated from beat-to-beat measurements of mean arterial blood pressure, mean cerebral blood flow velocity and end-tidal CO2, which can be made reliably and non-invasively under resting conditions. This model may also take an open-loop form and comparisons are made with the closed-loop counterpart. The proposed model-based physiomarkers take the form of two indices that quantify the gain of the CA and CVMR processes in each subject. It was found in an initial set of clinical data that the CVMR index delineates AD patients from control subjects and, therefore, may prove useful in the improved diagnosis of early-stage AD.
Collapse
Affiliation(s)
- V Z Marmarelis
- University of Southern California, Los Angeles, CA, USA,
| | | | | | | |
Collapse
|
8
|
Soares LM, Cachioni M, Falcão DVDS, Batistoni SST, Lopes A, Neri AL, Yassuda MS. Determinants of cognitive performance among community dwelling older adults in an impoverished sub-district of São Paulo in Brazil. Arch Gerontol Geriatr 2012; 54:e187-92. [PMID: 22222381 DOI: 10.1016/j.archger.2011.11.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Revised: 11/27/2011] [Accepted: 11/28/2011] [Indexed: 10/14/2022]
Abstract
Determinants of cognitive performance in old age have received limited attention in Latin America. We investigated the association of socio-demographic and health-related variables with cognitive performance in a sample of older adults with limited educational experience living in a poor sub-district of the city of São Paulo. This was a cross-sectional population-based study which included a sample of 384 seniors 65 years and older. Cognition was assessed by the Mini-Mental State Examination (MMSE) and the Brief Cognitive Screening Battery (BCSB) (episodic memory test with 10 pictures, verbal fluency (VF), Clock Drawing Test (CDT)). Results indicated that age, sex, schooling, depressive symptoms, and systolic blood pressure (SBP) level had a significant impact on the cognitive performance of the sample. Therefore, pharmacological and psychosocial interventions with a focus on improving mood and controlling hypertension may have beneficial effects on cognition among seniors with similar socio-demographic characteristics.
Collapse
|
9
|
Abstract
The relationship between blood pressure (BP) and cognitive outcomes in elderly adults has implications for global health care. Both hypertension and hypotension affect brain perfusion and worsen cognitive outcomes. The presence of hypertension and other vascular risk factors has been associated with decreased performance in executive function and attention tests. Cerebrovascular reserve has emerged as a potential biomarker for monitoring pressure-perfusion-cognition relationships. A decline in vascular reserve capacity can lead to impaired neurovascular coupling and decreased cognitive ability. Endothelial dysfunction, microvascular disease, and mascrovascular disease in midlife could also have an important role in the manifestations and severity of multiple medical conditions underlying cognitive decline late in life. However, questions remain about the role of antihypertensive therapies for long-term prevention of cognitive decline. In this Review, we address the underlying pathophysiology and the existing evidence supporting the role of vascular factors in late-life cognitive decline.
Collapse
Affiliation(s)
- Vera Novak
- Division of Gerontology, Beth Israel Deaconess Medical Center and Harvard Medical School, 110 Francis Street, LMOB Suite 1b, Boston, MA 02215, USA.
| | | |
Collapse
|
10
|
Gustafson DR, Melchior L, Eriksson E, Sundh V, Blennow K, Skoog I. The ACE Insertion Deletion polymorphism relates to dementia by metabolic phenotype, APOEepsilon4, and age of dementia onset. Neurobiol Aging 2008; 31:910-6. [PMID: 18838196 DOI: 10.1016/j.neurobiolaging.2008.07.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 06/24/2008] [Accepted: 07/19/2008] [Indexed: 10/21/2022]
Abstract
The renin-angiotensin system (RAS) may play a role in dementia pathogenesis because of its effects on vascular and metabolic homeostasis, amyloid metabolism, and learning and memory. The angiotensin-converting enzyme (ACE), a pivotal RAS protein, is encoded for by a gene containing a functional ID variant, which has been related to dementia risk. We examined the relationship between the ACE Insertion Deletion (ACE ID) variant and dementia with consideration for metabolic phenotypes, age and APOEepsilon4 using a population-based, cross-sectional sample of 891 Swedish women and men aged 70-92 years, of whom 61 people were demented. The odds of dementia was two-fold higher among those with ACE II genotype, and ranged from 2.18 to 4.35 among those with dementia onset <or=70 years, an APOEepsilon4 allele, systolic blood pressure <160 mmHg, body mass index <25 kg/m(2), and in women only, waist circumference <or=88 cm and hip circumference <101 cm. Variations among reports on the relationship between the ACE ID polymorphism and dementia may be due to lack of consideration for gene-gene and gene-phenotype associations.
Collapse
Affiliation(s)
- D R Gustafson
- Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Sweden.
| | | | | | | | | | | |
Collapse
|
11
|
Tang J, Wan JY, Bailey JE. Performance of Comorbidity Measures to Predict Stroke and Death in a Community-Dwelling, Hypertensive Medicaid Population. Stroke 2008; 39:1938-44. [DOI: 10.1161/strokeaha.107.504688] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
The Charlson and Elixhauser comorbidities are widely used to control for differences in comorbidity in epidemiological studies but have not been validated for outpatient studies of hypertension. This study sought that validation using death and stroke outcomes.
Methods—
Using Cox models in a retrospective cohort study of 49 479 hypertensive patients, Modified Charlson Index was compared with 6 alternative approaches to assessing comorbidity: individual Charlson comorbidities, Elixhauser comorbidities, prior major cardiovascular disease event, traditional risk factors for cerebrovascular accident, healthcare utilization, and antihypertensive medication utilization. Comorbidity measures were calculated at baseline and for a period before occurrence of the study outcome of interest or study conclusion.
Results—
The Charlson comorbidities had the smallest Akaike information criterion value for both the stroke and death outcomes when baseline data were used. The Elixhauser comorbidities had the smallest Akaike information criterion value for both the stroke and death outcomes when follow-up data were used. Modified Charlson Index also predicted stroke and death, but alternative models were more robust.
Conclusion—
This study indicates that both the Charlson and Elixhauser comorbidities are valid prediction tools that could enable clinicians and health systems to better assess risk for stroke and death in patients with hypertension. However, the Charlson comorbidities perform better when comorbidities are assessed using baseline data, whereas the Elixhauser comorbidities perform better for short follow-up periods when comorbidities are assessed proximal to events of interest.
Collapse
Affiliation(s)
- Jun Tang
- From the Department of Preventive Medicine (J.T., J.Y.W.) and the Division of General Internal Medicine, Department of Medicine (J.E.B.), University of Tennessee Health Science Center, Memphis, Tenn
| | - Jim Y. Wan
- From the Department of Preventive Medicine (J.T., J.Y.W.) and the Division of General Internal Medicine, Department of Medicine (J.E.B.), University of Tennessee Health Science Center, Memphis, Tenn
| | - James E. Bailey
- From the Department of Preventive Medicine (J.T., J.Y.W.) and the Division of General Internal Medicine, Department of Medicine (J.E.B.), University of Tennessee Health Science Center, Memphis, Tenn
| |
Collapse
|
12
|
|
13
|
Kehoe PG, Wilcock GK. Is inhibition of the renin-angiotensin system a new treatment option for Alzheimer's disease? Lancet Neurol 2007; 6:373-8. [PMID: 17362841 DOI: 10.1016/s1474-4422(07)70077-7] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Findings from longitudinal and cross-sectional studies suggest an association between high blood pressure and dementia, and in turn the use of antihypertensives has been suggested to reduce incidence of dementia. Alzheimer's disease, the most common cause of dementia, is characterised in part by the deposition of amyloid beta protein (Abeta) in the brain. Reduction of Abeta load is now a major therapeutic strategy. In recent years the renin-angiotensin system, already of recognised importance in the pathogenesis of hypertension, has become a source of interest in the pathogenesis of Alzheimer's disease. This review explores molecular, genetic, and clinical studies that might help explain the relation between the renin-angiotensin system, hypertension, and Alzheimer's disease and whether treatment with angiotensin converting enzyme (ACE) inhibitors and similar treatment strategies have a part to play in the management of the disease.
Collapse
Affiliation(s)
- Patrick G Kehoe
- Dementia Research Group, Institute of Clinical Neurosciences, Department of Clinical Science at North Bristol, University of Bristol, Frenchay Hospital, Frenchay, Bristol.
| | | |
Collapse
|
14
|
Silvestrini M, Pasqualetti P, Baruffaldi R, Bartolini M, Handouk Y, Matteis M, Moffa F, Provinciali L, Vernieri F. Cerebrovascular Reactivity and Cognitive Decline in Patients With Alzheimer Disease. Stroke 2006; 37:1010-5. [PMID: 16497984 DOI: 10.1161/01.str.0000206439.62025.97] [Citation(s) in RCA: 197] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The aim of this study was to explore the possible contribution of alterations in cerebral hemodynamics to the evolution of cognitive impairment in patients with Alzheimer disease (AD). METHOD Fifty-three patients with AD were investigated. The evolution of cognitive decline over 12 months was evaluated by means of changes in Mini Mental State Examination (MMSE) and AD Assessment Scale for Cognition (ADAS-Cog) scores. Demographic characteristics, vascular risk profile, pharmacological treatment, and presence of white matter lesions were assessed at entry. Further, a basal evaluation of cerebrovascular reactivity to hypercapnia was measured with transcranial Doppler ultrasonography using the breath-holding index (BHI). RESULTS Of all the variables considered, both MMSE and ADAS-Cog changes had the highest correlation with BHI, followed by age and diabetes. After subdividing both cognitive measures reductions into bigger and smaller-than-average decline (2 points for MMSE; 5 points for ADAS-Cog), multiple logistic regression indicated BHI as the sole significant predictor of cognitive decline. CONCLUSIONS These results show an association between impaired cerebral microvessels functionality and unfavorable evolution of cognitive function in patients with AD. Further research is needed to fully establish whether altered cerebral hemodynamics may be considered an independent factor in sustaining cognitive decline progression or an effect of pathological processes involved in AD.
Collapse
Affiliation(s)
- Mauro Silvestrini
- Neurological Clinic, Polytechnic University of Marche, Ancona, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Roy S, Rauk A. Alzheimer's disease and the 'ABSENT' hypothesis: mechanism for amyloid beta endothelial and neuronal toxicity. Med Hypotheses 2005; 65:123-37. [PMID: 15893129 DOI: 10.1016/j.mehy.2004.08.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2004] [Accepted: 08/13/2004] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease [AD] is the most common cause of dementia among people age 65 and older. One of the biggest stumbling blocks in developing effective drug therapy for Alzheimer's disease has been the lack of a comprehensive hypothesis that explains the mechanism behind all of the histopathological changes seen in patients suffering from Alzheimer's disease. An overview of the currently popular 'amyloid' and 'vascular' hypotheses for AD demonstrates that neither hypothesis by itself can explain all the known histopathological and biochemical lesions seen in Alzheimer's disease. The paper presents a hypothesis that tries to explain the mechanism behind almost all the histopathological changes, and varying clinical manifestations seen in both diagnosed AD and Vascular Dementia [VaD]. The new hypothesis is based on the known dual toxicity of beta amyloid to both vascular and neuronal tissues, their synergy and the resultant net effect on the onset and progression of AD. The new hypothesis therefore will be known as the Amyloid Beta Synergistic Endothelial and Neuronal Toxicity [ABSENT] hypothesis. The ABSENT hypothesis will try to show the common chemical mechanism behind almost all of the pathological changes seen in AD. According to the ABSENT hypothesis, beta amyloid itself generates all the free radicals that cause both vascular dysfunction and the neuronal damage seen in AD. The chemical mechanism proposed is based on evidence from physical chemistry experiments, calculations as well as in vitro/in vivo experiments. The ABSENT hypothesis does not favor one mode of beta amyloid-induced brain damage over the other, rather it considers the net effects of the neuronal stress/damage caused by both the cerebrovascular dysfunction and direct neurotoxicity caused by beta amyloid. The hypothesis states that each patient has a different balance of predisposing factors that modulate the extent of neurotoxicity and cerebrovascular dysfunction caused by beta amyloid and thereby explains the wide range and mixed nature of damage and dysfunction seen in the studies done on patients diagnosed with AD, VaD or 'mixed dementias'. According to the hypothesis, beta amyloid peptides are necessary if not sufficient to cause AD, VaD and mixed senile dementias. The hypothesis, therefore, proposes the term Beta Amyloid Dementias [BAD] to describe the conditions currently covered by the diagnoses of 'AD', 'VaD' and 'Mixed [senile] Dementias'. Finally, the ABSENT hypothesis tries to put forth a direct chemical mechanism behind the apparent synergy and increased association between old age, pre- and coexisting vascular disease, diabetes and AD.
Collapse
Affiliation(s)
- Samir Roy
- Department of Chemistry, University of Calgary, 2500 University Drive, NW Alberta, Canada T2N 1N4.
| | | |
Collapse
|