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Dixon-Woods M, Cavers D, Agarwal S, Annandale E, Arthur A, Harvey J, Hsu R, Katbamna S, Olsen R, Smith L, Riley R, Sutton AJ. Conducting a critical interpretive synthesis of the literature on access to healthcare by vulnerable groups. BMC Med Res Methodol 2006; 6:35. [PMID: 16872487 PMCID: PMC1559637 DOI: 10.1186/1471-2288-6-35] [Citation(s) in RCA: 1000] [Impact Index Per Article: 52.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Accepted: 07/26/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Conventional systematic review techniques have limitations when the aim of a review is to construct a critical analysis of a complex body of literature. This article offers a reflexive account of an attempt to conduct an interpretive review of the literature on access to healthcare by vulnerable groups in the UK METHODS: This project involved the development and use of the method of Critical Interpretive Synthesis (CIS). This approach is sensitised to the processes of conventional systematic review methodology and draws on recent advances in methods for interpretive synthesis. RESULTS Many analyses of equity of access have rested on measures of utilisation of health services, but these are problematic both methodologically and conceptually. A more useful means of understanding access is offered by the synthetic construct of candidacy. Candidacy describes how people's eligibility for healthcare is determined between themselves and health services. It is a continually negotiated property of individuals, subject to multiple influences arising both from people and their social contexts and from macro-level influences on allocation of resources and configuration of services. Health services are continually constituting and seeking to define the appropriate objects of medical attention and intervention, while at the same time people are engaged in constituting and defining what they understand to be the appropriate objects of medical attention and intervention. Access represents a dynamic interplay between these simultaneous, iterative and mutually reinforcing processes. By attending to how vulnerabilities arise in relation to candidacy, the phenomenon of access can be better understood, and more appropriate recommendations made for policy, practice and future research. DISCUSSION By innovating with existing methods for interpretive synthesis, it was possible to produce not only new methods for conducting what we have termed critical interpretive synthesis, but also a new theoretical conceptualisation of access to healthcare. This theoretical account of access is distinct from models already extant in the literature, and is the result of combining diverse constructs and evidence into a coherent whole. Both the method and the model should be evaluated in other contexts.
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Research Support, Non-U.S. Gov't |
19 |
1000 |
2
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Matthews FE, Arthur A, Barnes LE, Bond J, Jagger C, Robinson L, Brayne C. A two-decade comparison of prevalence of dementia in individuals aged 65 years and older from three geographical areas of England: results of the Cognitive Function and Ageing Study I and II. Lancet 2013; 382:1405-12. [PMID: 23871492 PMCID: PMC3906607 DOI: 10.1016/s0140-6736(13)61570-6] [Citation(s) in RCA: 680] [Impact Index Per Article: 56.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The prevalence of dementia is of interest worldwide. Contemporary estimates are needed to plan for future care provision, but much evidence is decades old. We aimed to investigate whether the prevalence of dementia had changed in the past two decades by repeating the same approach and diagnostic methods as used in the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS) in three of the original study areas in England. METHODS Between 1989 and 1994, MRC CFAS investigators did baseline interviews in populations aged 65 years and older in six geographically defined areas in England and Wales. A two stage process, with screening followed by diagnostic assessment, was used to obtain data for algorithmic diagnoses (geriatric mental state-automated geriatric examination for computer assisted taxonomy), which were then used to estimate dementia prevalence. Data from three of these areas--Cambridgeshire, Newcastle, and Nottingham--were selected for CFAS I. Between 2008 and 2011, new fieldwork was done in the same three areas for the CFAS II study. For both CFAS I and II, each area needed to include 2500 individuals aged 65 years and older to provide power for geographical and generational comparison. Sampling was stratified according to age group (65-74 years vs ≥75 years). CFAS II used identical sampling, approach, and diagnostic methods to CFAS I, except that screening and assessement were combined into one stage. Prevalence estimates were calculated using inverse probability weighting methods to adjust for sampling design and non-response. Full likelihood Bayesian models were used to investigate informative non-response. FINDINGS 7635 people aged 65 years or older were interviewed in CFAS I (9602 approached, 80% response) in Cambridgeshire, Newcastle, and Nottingham, with 1457 being diagnostically assessed. In the same geographical areas, the CFAS II investigators interviewed 7796 individuals (14,242 approached, 242 with limited frailty information, 56% response). Using CFAS I age and sex specific estimates of prevalence in individuals aged 65 years or older, standardised to the 2011 population, 8·3% (884,000) of this population would be expected to have dementia in 2011. However, CFAS II shows that the prevalence is lower (6·5%; 670,000), a decrease of 1·8% (odds ratio for CFAS II vs CFAS I 0·7, 95% CI 0·6-0·9, p=0·003). Sensitivity analyses suggest that these estimates are robust to the change in response. INTERPRETATION This study provides further evidence that a cohort effect exists in dementia prevalence. Later-born populations have a lower risk of prevalent dementia than those born earlier in the past century. FUNDING UK Medical Research Council.
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Comparative Study |
12 |
680 |
3
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Coupland C, Dhiman P, Morriss R, Arthur A, Barton G, Hippisley-Cox J. Antidepressant use and risk of adverse outcomes in older people: population based cohort study. BMJ 2011; 343:d4551. [PMID: 21810886 PMCID: PMC3149102 DOI: 10.1136/bmj.d4551] [Citation(s) in RCA: 522] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES To investigate the association between antidepressant treatment and risk of several potential adverse outcomes in older people with depression and to examine risks by class of antidepressant, duration of use, and dose. DESIGN Cohort study of people aged 65 and over diagnosed as having depression. SETTING 570 general practices in the United Kingdom supplying data to the QResearch primary care database. PARTICIPANTS 60,746 patients diagnosed as having a new episode of depression between the ages of 65 and 100 years from 1 January 1996 to 31 December 2007 and followed up until 31 December 2008. MAIN OUTCOME MEASURES Hazard ratios associated with antidepressant use for all cause mortality, attempted suicide/self harm, myocardial infarction, stroke/transient ischaemic attack, falls, fractures, upper gastrointestinal bleeding, epilepsy/seizures, road traffic accidents, adverse drug reactions, and hyponatraemia, adjusted for a range of potential confounding variables. Hazard ratios were calculated for antidepressant class (tricyclic and related antidepressants, selective serotonin reuptake inhibitors, other antidepressants), dose, and duration of use and for commonly prescribed individual drugs. RESULTS 54,038 (89.0%) patients received at least one prescription for an antidepressant during follow-up. A total of 1,398,359 antidepressant prescriptions were issued: 764,659 (54.7%) for selective serotonin reuptake inhibitors, 442,192 (31.6%) for tricyclic antidepressants, 2203 (0.2%) for monoamine oxidase inhibitors, and 189,305 (13.5%) for the group of other antidepressants. The associations with the adverse outcomes differed significantly between the antidepressant classes for seven outcomes. Selective serotonin reuptake inhibitors were associated with the highest adjusted hazard ratios for falls (1.66, 95% confidence interval 1.58 to 1.73) and hyponatraemia (1.52, 1.33 to 1.75) compared with when antidepressants were not being used. The group of other antidepressants was associated with the highest adjusted hazard ratios for all cause mortality (1.66, 1.56 to 1.77), attempted suicide/self harm (5.16, 3.90 to 6.83), stroke/transient ischaemic attack (1.37, 1.22 to 1.55), fracture (1.64, 1.46 to 1.84), and epilepsy/seizures (2.24, 1.60 to 3.15), compared with when antidepressants were not being used. Tricyclic antidepressants did not have the highest hazard ratio for any of the outcomes. Significantly different associations also existed between the individual drugs for the same seven outcomes; trazodone (tricyclic antidepressant), mirtazapine, and venlafaxine (both in the group of other antidepressants) were associated with the highest rates for some of these outcomes. Absolute risks over 1 year for all cause mortality were 7.04% for patients while not taking antidepressants, 8.12% for those taking tricyclic antidepressants, 10.61% for selective serotonin reuptake inhibitors, and 11.43% for other antidepressants. CONCLUSIONS Selective serotonin reuptake inhibitors and drugs in the group of other antidepressants were associated with an increased risk of several adverse outcomes compared with tricyclic antidepressants. Among individual drugs, trazodone, mirtazapine, and venlafaxine were associated with the highest risks for some outcomes. As this is an observational study, it is susceptible to confounding by indication, channelling bias, and residual confounding, so differences in characteristics between patients prescribed different antidepressant drugs that could account for some of the associations between the drugs and the adverse outcomes may remain. Further research is needed to confirm these findings, but the risks and benefits of different antidepressants should be carefully evaluated when these drugs are prescribed to older people.
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research-article |
14 |
522 |
4
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Zannettino ACW, Paton S, Arthur A, Khor F, Itescu S, Gimble JM, Gronthos S. Multipotential human adipose-derived stromal stem cells exhibit a perivascular phenotype in vitro and in vivo. J Cell Physiol 2007; 214:413-21. [PMID: 17654479 DOI: 10.1002/jcp.21210] [Citation(s) in RCA: 395] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mesenchymal stem-like cells identified in different tissues reside in a perivascular niche. In the present study, we investigated the putative niche of adipose-derived stromal/stem cells (ASCs) using markers, associated with mesenchymal and perivascular cells, including STRO-1, CD146, and 3G5. Immunofluorescence staining of human adipose tissue sections, revealed that STRO-1 and 3G5 co-localized with CD146 to the perivascular regions of blood vessels. FACS was used to determine the capacity of the CD146, 3G5, and STRO-1 specific monoclonal antibodies to isolate clonogenic ASCs from disassociated human adipose tissue. Clonogenic fibroblastic colonies (CFU-F) were found to be enriched in those cell fractions selected with either STRO-1, CD146, or 3G5. Flow cytometric analysis revealed that cultured ASCs exhibited similar phenotypic profiles in relation to their expression of cell surface markers associated with stromal cells (CD44, CD90, CD105, CD106, CD146, CD166, STRO-1, alkaline phosphatase), endothelial cells (CD31, CD105, CD106, CD146, CD166), haematopoietic cells (CD14, CD31, CD45), and perivascular cells (3G5, STRO-1, CD146). The immunoselected ASCs populations maintained their characteristic multipotential properties as shown by their capacity to form Alizarin Red positive mineralized deposits, Oil Red O positive lipid droplets, and Alcian Blue positive proteoglycan-rich matrix in vitro. Furthermore, ASCs cultures established from either STRO-1, 3G5, or CD146 selected cell populations, were all capable of forming ectopic bone when transplanted subcutaneously into NOD/SCID mice. The findings presented here, describe a multipotential stem cell population within adult human adipose tissue, which appear to be intimately associated with perivascular cells surrounding the blood vessels.
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Research Support, Non-U.S. Gov't |
18 |
395 |
5
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Robinson CM, Goudie EB, Murray IR, Jenkins PJ, Ahktar MA, Read EO, Foster CJ, Clark K, Brooksbank AJ, Arthur A, Crowther MA, Packham I, Chesser TJ. Open reduction and plate fixation versus nonoperative treatment for displaced midshaft clavicular fractures: a multicenter, randomized, controlled trial. J Bone Joint Surg Am 2013; 95:1576-84. [PMID: 24005198 DOI: 10.2106/jbjs.l.00307] [Citation(s) in RCA: 278] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND There is a growing trend to treat displaced midshaft clavicular fractures with primary open reduction and plate fixation; whether such treatment results in improved patient outcomes is debatable. The aim of this multicenter, single-blinded, randomized controlled trial was to compare union rates, functional outcomes, and economic costs for displaced midshaft clavicular fractures that were treated with either primary open reduction and plate fixation or nonoperative treatment. METHODS In a prospective, multicenter, stratified, randomized controlled trial, 200 patients between sixteen and sixty years of age who had an acute displaced midshaft clavicular fracture were randomized to receive either primary open reduction and plate fixation or nonoperative treatment. Functional assessment was conducted at six weeks, three months, six months, and one year with use of the Disabilities of the Arm, Shoulder and Hand (DASH) and Constant scores. Union was evaluated with use of three-dimensional computed tomography. Complications were recorded, and an economic evaluation was performed. RESULTS The rate of nonunion was significantly reduced after open reduction and plate fixation (one nonunion) as compared with nonoperative treatment (sixteen nonunions) (relative risk = 0.07; p = 0.007). Group allocation to nonoperative treatment was independently predictive of the development of nonunion (p = 0.0001). Overall, DASH and Constant scores were significantly better after open reduction and plate fixation than after nonoperative treatment at the time of the one-year follow-up (DASH score, 3.4 versus 6.1 [p = 0.04]; Constant score, 92.0 versus 87.8 [p = 0.01]). However, when patients with nonunion were excluded from analysis, there were no significant differences in the Constant scores or DASH scores at any time point. Patients were less dissatisfied with symptoms of shoulder droop, local bump at the fracture site, and shoulder asymmetry in the open reduction and plate fixation group (p < 0.0001). The cost of treatment was significantly greater after open reduction and plate fixation (p < 0.0001). CONCLUSIONS Open reduction and plate fixation reduces the rate of nonunion after acute displaced midshaft clavicular fracture compared with nonoperative treatment and is associated with better functional outcomes. However, the improved outcomes appear to result from the prevention of nonunion by open reduction and plate fixation. Open reduction and plate fixation is more expensive and is associated with implant-related complications that are not seen in association with nonoperative treatment. The results of the present study do not support routine primary open reduction and plate fixation for the treatment of displaced midshaft clavicular fractures.
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Multicenter Study |
12 |
278 |
6
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Richardson K, Fox C, Maidment I, Steel N, Loke YK, Arthur A, Myint PK, Grossi CM, Mattishent K, Bennett K, Campbell NL, Boustani M, Robinson L, Brayne C, Matthews FE, Savva GM. Anticholinergic drugs and risk of dementia: case-control study. BMJ 2018; 361:k1315. [PMID: 29695481 PMCID: PMC5915701 DOI: 10.1136/bmj.k1315] [Citation(s) in RCA: 271] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/07/2018] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To estimate the association between the duration and level of exposure to different classes of anticholinergic drugs and subsequent incident dementia. DESIGN Case-control study. SETTING General practices in the UK contributing to the Clinical Practice Research Datalink. PARTICIPANTS 40 770 patients aged 65-99 with a diagnosis of dementia between April 2006 and July 2015, and 283 933 controls without dementia. INTERVENTIONS Daily defined doses of anticholinergic drugs coded using the Anticholinergic Cognitive Burden (ACB) scale, in total and grouped by subclass, prescribed 4-20 years before a diagnosis of dementia. MAIN OUTCOME MEASURES Odds ratios for incident dementia, adjusted for a range of demographic and health related covariates. RESULTS 14 453 (35%) cases and 86 403 (30%) controls were prescribed at least one anticholinergic drug with an ACB score of 3 (definite anticholinergic activity) during the exposure period. The adjusted odds ratio for any anticholinergic drug with an ACB score of 3 was 1.11 (95% confidence interval 1.08 to 1.14). Dementia was associated with an increasing average ACB score. When considered by drug class, gastrointestinal drugs with an ACB score of 3 were not distinctively linked to dementia. The risk of dementia increased with greater exposure for antidepressant, urological, and antiparkinson drugs with an ACB score of 3. This result was also observed for exposure 15-20 years before a diagnosis. CONCLUSIONS A robust association between some classes of anticholinergic drugs and future dementia incidence was observed. This could be caused by a class specific effect, or by drugs being used for very early symptoms of dementia. Future research should examine anticholinergic drug classes as opposed to anticholinergic effects intrinsically or summing scales for anticholinergic exposure. TRIAL REGISTRATION Registered to the European Union electronic Register of Post-Authorisation Studies EUPAS8705.
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research-article |
7 |
271 |
7
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Arthur A, Sherratt D. Dissection of the transposition process: a transposon-encoded site-specific recombination system. MOLECULAR & GENERAL GENETICS : MGG 1979; 175:267-74. [PMID: 392228 DOI: 10.1007/bf00397226] [Citation(s) in RCA: 183] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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46 |
183 |
8
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Avis M, Bond M, Arthur A. Satisfying solutions? A review of some unresolved issues in the measurement of patient satisfaction. J Adv Nurs 1995; 22:316-22. [PMID: 7593953 DOI: 10.1046/j.1365-2648.1995.22020316.x] [Citation(s) in RCA: 167] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The measurement of patient satisfaction has been encouraged by a growing consumer orientation in health care, especially since it yields information about consumers' views in a form which can be used for comparison and monitoring. However, drawing on literature from a variety of sources, this paper suggests that there remain several unresolved issues relating to the measurement of satisfaction, and some serious questions about the validity of the concept. It is argued that current approaches to measuring satisfaction may not be grounded in the values and experiences of patients; therefore satisfaction surveys could be denying patients the opportunity to have their opinions included in the planning and evaluation of health care services.
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Review |
30 |
167 |
9
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Lee LL, Arthur A, Avis M. Using self-efficacy theory to develop interventions that help older people overcome psychological barriers to physical activity: a discussion paper. Int J Nurs Stud 2008; 45:1690-9. [PMID: 18501359 DOI: 10.1016/j.ijnurstu.2008.02.012] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 12/22/2007] [Accepted: 02/28/2008] [Indexed: 11/19/2022]
Abstract
BACKGROUND Only a fifth of older people undertake a level of physical activity sufficient to lead to health benefit. Misconceptions about the ageing process and beliefs about the costs and benefits of exercise in late life may result in unnecessary self-imposed activity restriction. Thus, adhering to a physical activity can be difficult particularly when the benefits of exercise are often not immediate. Many of the barriers to engaging in physical activity among older people are attitudinal. It is therefore important to take account of the non-physical aspects of physical activity intervention programmes, such as increasing confidence. Self-efficacy is a widely applied theory used to understand health behaviour and facilitate behavioural modification, such as the increase of physical activity. AIM This paper aims to examine the ways in which self-efficacy theory might be used in intervention programmes designed to overcome psychological barriers for increasing physical activity among older people. CONCLUSION A number of studies have demonstrated that exercise self-efficacy is strongly associated with the amount of physical activity undertaken. Evidence from some trials supports the view that incorporating the theory of self-efficacy into the design of a physical activity intervention is beneficial. Physical activity interventions aimed at improving the self perception of exercise self-efficacy can have positive effects on confidence and the ability to initiate and maintain physical activity behaviour. There are a number of ways for nurses to facilitate older people to draw on the four information sources of self-efficacy: performance accomplishments, vicarious learning, verbal encouragement, and physiological and affective states. Research challenges that future studies need to address include the generalisability of exercise setting, the role of age as an effect modifier, and the need for more explicit reporting of how self-efficacy is operationalised in interventions.
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Review |
17 |
142 |
10
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Jagger C, Matthews FE, Wohland P, Fouweather T, Stephan BCM, Robinson L, Arthur A, Brayne C. A comparison of health expectancies over two decades in England: results of the Cognitive Function and Ageing Study I and II. Lancet 2016; 387:779-86. [PMID: 26680218 PMCID: PMC4761658 DOI: 10.1016/s0140-6736(15)00947-2] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Whether rises in life expectancy are increases in good-quality years is of profound importance worldwide, with population ageing. We investigate how various health expectancies have changed in England between 1991 and 2011, with identical study design and methods in each decade. METHODS Baseline data from the Cognitive Function and Ageing Studies in populations aged 65 years or older in three geographically defined centres in England (Cambridgeshire, Newcastle, and Nottingham) provided prevalence estimates for three health measures: self-perceived health (defined as excellent-good, fair, or poor); cognitive impairment (defined as moderate-severe, mild, or none, as assessed by Mini-Mental State Examination score); and disability in activities of daily living (defined as none, mild, or moderate-severe). Health expectancies for the three regions combined were calculated by the Sullivan method, which applies the age-specific and sex-specific prevalence of the health measure to a standard life table for the same period. FINDINGS Between 1991 and 2011, gains in life expectancy at age 65 years (4·5 years for men and 3·6 years for women) were accompanied by equivalent gains in years free of any cognitive impairment (4·2 years [95% CI 4·2-4·3] for men and 4·4 years [4·3-4·5] for women) and decreased years with mild or moderate-severe cognitive impairment. Gains were also identified in years in excellent or good self-perceived health (3·8 years [95% CI 3·5-4·1] for men and 3·1 years [2·7-3·4] for women). Gains in disability-free years were much smaller than those in excellent-good self-perceived health or those free from cognitive impairment, especially for women (0·5 years [0·2-0·9] compared with 2·6 years [2·3-2·9] for men), mostly because of increased mild disability. INTERPRETATION During the past two decades in England, we report an absolute compression (ie, reduction) of cognitive impairment, a relative compression of self-perceived health (ie, proportion of life spent healthy is increasing), and dynamic equilibrium of disability (ie, less severe disability is increasing but more severe disability is not). Reasons for these patterns are unknown but might include increasing obesity during previous decades. Our findings have wide-ranging implications for health services and for extension of working life. FUNDING UK Medical Research Council.
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Comparative Study |
9 |
114 |
11
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Szmania S, Galloway A, Bruorton M, Musk P, Aubert G, Arthur A, Pyle H, Hensel N, Ta N, Lamb L, Dodi T, Madrigal A, Barrett J, Henslee-Downey J, van Rhee F. Isolation and expansion of cytomegalovirus-specific cytotoxic T lymphocytes to clinical scale from a single blood draw using dendritic cells and HLA-tetramers. Blood 2001; 98:505-12. [PMID: 11468143 DOI: 10.1182/blood.v98.3.505] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cytomegalovirus (CMV) reactivation in immunocompromised recipients of allogeneic stem cell transplantation is a cause of morbidity and mortality from viral pneumonitis. Antiviral drugs given to reactivating patients have reduced the mortality from CMV but have toxic side effects and do not always prevent late CMV disease. Cellular immunotherapy to prevent CMV disease is less toxic and could provide prolonged protection. However, a practical approach to generating sufficient quantities of CMV-specific cytotoxic T cells (CTLs) is required. This study describes a system for generating sufficient CMV-specific CTLs for adoptive immunotherapy of HLA-A*0201 bone marrow transplant recipients from 200 mL donor blood. Donor monocytes are used to generate dendritic cells (DCs) in medium with autologous plasma, interleukin 4, granulocyte-macrophage colony-stimulating factor, and CD40 ligand. The DCs are pulsed with the immunodominant HLA-A*0201-restricted CMV peptide pp65(495-503), and incubated with donor T cells. These cultures are restimulated twice with peptide-pulsed lymphoblastoid cell lines (LCLs) or CD40-ligated B cells and purified with phycoerythrin (PE)-labeled pp65(495-503)/HLA-A*0201 tetramers by flow sorting, or with anti-PE paramagnetic beads. The pure tetramer-positive population is then rapidly expanded to obtain sufficient cells for clinical immunotherapy. The expanded CTLs are more than 80% pure, of memory phenotype, with a Tc1 cytokine profile. They efficiently kill CMV-infected fibroblasts and express the integrin VLA-4, suggesting that the CTLs could cross endothelial barriers. This technique is reproducible and could be used for generating CMV-specific CTLs to prevent CMV disease after allogeneic blood and marrow transplantation. (Blood. 2001;98:505-512)
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24 |
109 |
12
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Guo P, East L, Arthur A. A preoperative education intervention to reduce anxiety and improve recovery among Chinese cardiac patients: A randomized controlled trial. Int J Nurs Stud 2012; 49:129-37. [DOI: 10.1016/j.ijnurstu.2011.08.008] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 08/11/2011] [Accepted: 08/22/2011] [Indexed: 11/24/2022]
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13 |
107 |
13
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Avis M, Bond M, Arthur A. Questioning patient satisfaction: An empirical investigation in two outpatient clinics. Soc Sci Med 1997. [DOI: 10.1016/s0277-9536(96)00140-2] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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28 |
106 |
14
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Savva GM, Arthur A. Who has undiagnosed dementia? A cross-sectional analysis of participants of the Aging, Demographics and Memory Study. Age Ageing 2015; 44:642-7. [PMID: 25758406 DOI: 10.1093/ageing/afv020] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 01/07/2015] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND delays in diagnosing dementia may lead to suboptimal care, yet around half of those with dementia are undiagnosed. Any strategy for case finding should be informed by understanding the characteristics of the undiagnosed population. We used cross-sectional data from a population-based sample with dementia aged 71 years and older in the United States to describe the undiagnosed population and identify factors associated with non-diagnosis. METHODS the Aging, Demographics and Memory Study (ADAMS) Wave A participants (N = 856) each underwent a detailed neuropsychiatric investigation. Informants were asked whether the participant had ever received a doctor's diagnosis of dementia. We used multiple logistic regression to identify factors associated with informant report of a prior dementia diagnosis among those with a study diagnosis of dementia. RESULTS of those with a study diagnosis of dementia (n = 307), a prior diagnosis of dementia was reported by 121 informants (weighted proportion = 42%). Prior diagnosis was associated with greater clinical dementia rating (CDR), from 26% (CDR = 1) to 83% (CDR = 5). In multivariate analysis, those aged 90 years or older were less likely to be diagnosed (P = 0.008), but prior diagnosis was more common among married women (P = 0.038) and those who had spent more than 9 years in full-time education (P = 0.043). CONCLUSIONS people with dementia who are undiagnosed are older, have fewer years in education, are more likely to be unmarried, male and have less severe dementia than those with a diagnosis. Policymakers and clinicians should be mindful of the variation in diagnosis rates among subgroups of the population with dementia.
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Multicenter Study |
10 |
97 |
15
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Imperato-McGinley J, Peterson RE, Gautier T, Cooper G, Danner R, Arthur A, Morris PL, Sweeney WJ, Shackleton C. Hormonal evaluation of a large kindred with complete androgen insensitivity: evidence for secondary 5 alpha-reductase deficiency. J Clin Endocrinol Metab 1982; 54:931-41. [PMID: 6801078 DOI: 10.1210/jcem-54-5-931] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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43 |
91 |
16
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Spiers N, Jagger C, Clarke M, Arthur A. Are gender differences in the relationship between self-rated health and mortality enduring? Results from three birth cohorts in Melton Mowbray, United Kingdom. THE GERONTOLOGIST 2003; 43:406-11; discussion 372-5. [PMID: 12810905 DOI: 10.1093/geront/43.3.406] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
PURPOSE The purpose of this study was to assess whether there is an enduring gender difference in the ability of self-rated health to predict mortality and investigate whether self-reported physical health problems account for this difference. DESIGN AND METHODS Cox models for 4-year survival were fitted to data from successive cohorts aged 75-81 years registered with a primary care practice in the U.K. Midlands surveyed in 1981, 1988, and 1993-1995. RESULTS Self-rated health was consistently a stronger predictor in men (hazard ratio [HR] = 2.7; 95% confidence interval [CI] = 2.1-3.5) than it was in women (HR = 1.9; 95% CI = 1.5-2.4). Women surveyed in 1993-1995 were more likely than men to report problems that were disabling but not life-threatening, whereas men were more likely to report potentially life-threatening problems. However, these differences did not explain the association of self-rated health with mortality. More than half of those who reported a potentially life-threatening problem said that their health was good. IMPLICATIONS Self-rated health is more strongly associated with mortality in men, but this is unlikely to be explained by differences in the nature of their physical health problems.
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Coupland CAC, Dhiman P, Barton G, Morriss R, Arthur A, Sach T, Hippisley-Cox J. A study of the safety and harms of antidepressant drugs for older people: a cohort study using a large primary care database. Health Technol Assess 2011; 15:1-202, iii-iv. [PMID: 21810375 DOI: 10.3310/hta15280] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES The aim of this study was to establish the relative safety and balance of risks for antidepressant treatment in older people. The study objectives were to (1) determine relative and absolute risks of predefined adverse events in older people with depression, comparing classes of antidepressant drugs [tricyclic and related antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs) and other antidepressants] and commonly prescribed individual drugs with non-use of antidepressant drugs; (2) directly compare the risk of adverse events for SSRIs with TCAs; (3) determine associations with dose and duration of antidepressant medication; (4) describe patterns of antidepressant use in older people with depression; and (5) estimate costs of antidepressant medication and primary care visits. DESIGN A cohort study of patients aged 65 years and over diagnosed with depression. SETTING The study was based in 570 general practices in the UK supplying data to the QResearch database. PARTICIPANTS Patients diagnosed with a new episode of depression between the ages of 65 and 100 years, from 1 January 1996 to 31 December 2007. Participants were followed up until 31 December 2008. INTERVENTIONS The exposure of interest was treatment with antidepressant medication. Antidepressant drugs were grouped into the major classes and commonly prescribed individual drugs were identified. MAIN OUTCOME MEASURES There were 13 predefined outcome measures: all-cause mortality, sudden cardiac death, suicide, attempted suicide/self-harm, myocardial infarction, stroke/transient ischaemic attack (TIA), falls, fractures, upper gastrointestinal bleeding, epilepsy/seizures, road traffic accidents, adverse drug reactions and hyponatraemia. RESULTS In total, 60,746 patients were included in the study cohort. Of these, 54,038 (89.0%) received at least one prescription for an antidepressant during follow-up. The associations with the adverse outcomes were significantly different between the classes of antidepressant drugs for seven outcomes. SSRIs were associated with the highest adjusted hazard ratios (HRs) for falls [1.66, 95% confidence interval (CI) 1.58 to 1.73] and hyponatraemia (1.52, 95% CI 1.33 to 1.75), and the group of other antidepressants was associated with the highest HRs for all-cause mortality (1.66, 95% CI 1.56 to 1.77), attempted suicide/self-harm (5.16, 95% CI 3.90 to 6.83), stroke/TIA (1.37, 95% CI 1.22 to 1.55), fracture (1.63, 95% CI 1.45 to 1.83) and epilepsy/seizures (2.24, 95% CI 1.60 to 3.15) compared with when antidepressants were not being used. TCAs did not have the highest HR for any of the outcomes. There were also significantly different associations between the individual drugs for seven outcomes, with trazodone, mirtazapine and venlafaxine associated with the highest rates for several of these outcomes. The mean incremental cost (for all antidepressant prescriptions) ranged between £51.58 (amitriptyline) and £641.18 (venlafaxine) over the 5-year post-diagnosis period. CONCLUSIONS This study found associations between use of antidepressant drugs and a number of adverse events in older people. There was no evidence that SSRIs or drugs in the group of other antidepressants were associated with a reduced risk of any of the adverse outcomes compared with TCAs; however, they may be associated with an increased risk for certain outcomes. Among individual drugs trazodone, mirtazapine and venlafaxine were associated with the highest rates for some outcomes. Indication bias and residual confounding may explain some of the study findings. The risks of prescribing antidepressants need to be weighed against the potential benefits of these drugs. FUNDING The National Institute for Health Research Health Technology Assessment programme.
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Coupland C, Hill T, Morriss R, Arthur A, Moore M, Hippisley-Cox J. Antidepressant use and risk of suicide and attempted suicide or self harm in people aged 20 to 64: cohort study using a primary care database. BMJ 2015; 350:h517. [PMID: 25693810 PMCID: PMC4353276 DOI: 10.1136/bmj.h517] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To assess the associations between different antidepressant treatments and the rates of suicide and attempted suicide or self harm in people with depression. DESIGN Cohort study. SETTING Patients registered with UK general practices contributing data to the QResearch database. PARTICIPANTS 238,963 patients aged 20 to 64 years with a first diagnosis of depression between 1 January 2000 and 31 July 2011, followed up until 1 August 2012. EXPOSURES Antidepressant class (tricyclic and related antidepressants, selective serotonin reuptake inhibitors, other antidepressants), dose, and duration of use, and commonly prescribed individual antidepressant drugs. Cox proportional hazards models were used to calculate hazard ratios adjusting for potential confounding variables. MAIN OUTCOME MEASURES Suicide and attempted suicide or self harm during follow-up. RESULTS During follow-up, 87.7% (n = 209,476) of the cohort received one or more prescriptions for antidepressants. The median duration of treatment was 221 days (interquartile range 79-590 days). During the first five years of follow-up 198 cases of suicide and 5243 cases of attempted suicide or self harm occurred. The difference in suicide rates during periods of treatment with tricyclic and related antidepressants compared with selective serotonin reuptake inhibitors was not significant (adjusted hazard ratio 0.84, 95% confidence interval 0.47 to 1.50), but the suicide rate was significantly increased during periods of treatment with other antidepressants (2.64, 1.74 to 3.99). The hazard ratio for suicide was significantly increased for mirtazapine compared with citalopram (3.70, 2.00 to 6.84). Absolute risks of suicide over one year ranged from 0.02% for amitriptyline to 0.19% for mirtazapine. There was no significant difference in the rate of attempted suicide or self harm with tricyclic antidepressants (0.96, 0.87 to 1.08) compared with selective serotonin reuptake inhibitors, but the rate of attempted suicide or self harm was significantly higher for other antidepressants (1.80, 1.61 to 2.00). The adjusted hazard ratios for attempted suicide or self harm were significantly increased for three of the most commonly prescribed drugs compared with citalopram: venlafaxine (1.85, 1.61 to 2.13), trazodone (1.73, 1.26 to 2.37), and mirtazapine (1.70, 1.44 to 2.02), and significantly reduced for amitriptyline (0.71, 0.59 to 0.85). The absolute risks of attempted suicide or self harm over one year ranged from 1.02% for amitriptyline to 2.96% for venlafaxine. Rates were highest in the first 28 days after starting treatment and remained increased in the first 28 days after stopping treatment. CONCLUSION Rates of suicide and attempted suicide or self harm were similar during periods of treatment with selective serotonin reuptake inhibitors and tricyclic and related antidepressants. Mirtazapine, venlafaxine, and trazodone were associated with the highest rates of suicide and attempted suicide or self harm, but the number of suicide events was small leading to imprecise estimates. As this is an observational study the findings may reflect indication biases and residual confounding from severity of depression and differing characteristics of patients prescribed these drugs. The increased rates in the first 28 days of starting and stopping antidepressants emphasise the need for careful monitoring of patients during these periods.
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Imperato-McGinley J, Binienda Z, Arthur A, Mininberg DT, Vaughan ED, Quimby FW. The development of a male pseudohermaphroditic rat using an inhibitor of the enzyme 5 alpha-reductase. Endocrinology 1985; 116:807-12. [PMID: 3967629 DOI: 10.1210/endo-116-2-807] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Incomplete masculinization of the external genitalia occurred in male Sprague-Dawley rats treated with a potent inhibitor of enzyme 5 alpha-reductase at the critical period of sexual differentiation in utero. The studies were performed using the 5 alpha-reductase inhibitor, 4-methyl-4-aza-5-pregnan-3-one-20[s] carboxylate, one of a series of aza steroids known to competitively inhibit the enzyme 5 alpha-reductase. The degree of inhibition of male external genital development was dependent upon the dose of the inhibitor, and at a dose of 36 mg/kg X day, there was complete feminization of the external genitalia of the male animal with a urogenital sinus and a pseudovagina. These studies provide conclusive evidence for the hypothesis that 5 alpha-reductase activity and dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) formation are essential for normal differentiation of male external genitalia. Epididymidis, vasa deferentia, and seminal vesicles were present at all doses of the inhibitor, suggesting testosterone dependency. However, confirmation of the testosterone dependency of Wolffian ductal differentiation awaits further studies, particularly comparison studies with the rabbit and dog, since Wolffian ductal differentiation in the rat, unlike the rabbit and dog, is not abolished with the antiandrogen, cyproterone acetate. The presence of prostatic buds, despite complete external genital feminization, was unexpected and suggests that these structures may have different thresholds of response for dihydrotestosterone. Prostatic differentiation may have a much lower threshold, requiring less dihydrotestosterone for differentiation.
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Porter B, Arthur A, Savva GM. How do potentially inappropriate medications and polypharmacy affect mortality in frail and non-frail cognitively impaired older adults? A cohort study. BMJ Open 2019; 9:e026171. [PMID: 31092652 PMCID: PMC6530304 DOI: 10.1136/bmjopen-2018-026171] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES To test whether the use of potentially inappropriate central nervous system acting medications, proton pump inhibitors (PPIs) or polypharmacy are associated with mortality in cognitively impaired older adults and whether frailer people are at greater risk of harm. SETTING A cohort study nested within the Cognitive Function and Ageing Study II, a population representative cohort study of the older population in Cambridgeshire, Nottingham and Newcastle, UK. PARTICIPANTS A total of 1154 cognitively impaired participants, aged 65 years or older. EXPOSURES Any use of antipsychotics, antidepressants, other anticholinergic medication, benzodiazepines or PPIs, polypharmacy (5-9) and hyperpolypharmacy (≥10 reported medications) were ascertained at baseline. Frailty was assessed using the Fried criteria. PRIMARY OUTCOME Mortality up to 8 years follow-up. HRs associated with potentially inappropriate medication (PIM), frailty and their interaction were estimated adjusting for covariates. RESULTS Within the sample, 44% were taking one or more PIM. Apart from antipsychotics (adjusted HR=3.24, 95% CI 1.83 to 5.73), use of specific PIM was not associated with greater subsequent mortality. Polypharmacy (HR=1.17, 95% CI 0.95 to 1.45) and hyperpolypharmacy were associated with mortality (HR=1.60, 95% CI 1.16 to 2.22). Being frail (HR=1.90, 95% CI 1.32 to 2.72) or prefrail (HR=1.56, 95% CI 1.10 to 2.20) was associated with increased mortality. There was some evidence that the HR for polypharmacy on mortality was lower among frailer individuals, but the overall polypharmacy by frailty interaction was not statistically significant (p=0.102). CONCLUSIONS For those with cognitive impairment, greater concern should be afforded to the number of medications than the prescription of specific classes. Frailer individuals may have a lower relative risk of mortality associated with polypharmacy than less frail individuals.
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Lee LL, Arthur A, Avis M. Evaluating a community-based walking intervention for hypertensive older people in Taiwan: a randomized controlled trial. Prev Med 2007; 44:160-6. [PMID: 17055561 DOI: 10.1016/j.ypmed.2006.09.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Revised: 09/01/2006] [Accepted: 09/01/2006] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To study the effect of a community-based walking intervention on blood pressure among older people. METHOD The study design was a randomized controlled trial conducted in a rural area of Taiwan between October 2002 and June 2003. A total of 202 participants aged 60 years and over with mild to moderate hypertension was recruited. Participants randomized to the intervention group (n=102) received a six-month community-based walking intervention based on self-efficacy theory. A public health nurse provided both face-to-face and telephone support designed to assist participants to increase their walking. Control group participants (n=100) received usual primary health care. Primary outcome was change in systolic blood pressure and secondary outcomes were exercise self-efficacy, self-reported walking and diastolic blood pressure. RESULTS At six-month follow-up the mean change in systolic blood pressure was a decrease of 15.4 mmHg and 8.4 mmHg in the intervention and control group, respectively. The difference in mean change between the two groups was -7.0 mmHg (95% CI, -11.5 to -2.5 mmHg, p=0.002). Improvement in exercise self-efficacy scores was greater among intervention group participants (mean difference 1.23, 95% CI, 0.5 to 2.0, p=0.001). Intervention group participants were more likely to report walking more (p<0.0005) but no differences were observed in diastolic blood pressure (p=0.19). CONCLUSIONS Among hypertensive older people, a six-month community-based walking intervention was effective in increasing their exercise self-efficacy and reducing systolic blood pressure.
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Clinical Trial |
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Lee LL, Perng SJ, Ho CC, Hsu HM, Lau SC, Arthur A. A preliminary reliability and validity study of the Chinese version of the self-efficacy for exercise scale for older adults. Int J Nurs Stud 2008; 46:230-8. [PMID: 18950769 DOI: 10.1016/j.ijnurstu.2008.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 08/16/2008] [Accepted: 09/04/2008] [Indexed: 11/17/2022]
Abstract
BACKGROUND Population ageing affects most undeveloped, developing and developed countries. Less than a quarter of older people undertake a level of physical activity worldwide that is sufficient to lead to health benefits. Understanding older people's confidence regarding engaging in exercise helps to structure physical activity interventions that motivate them to initiate and adhere to regular exercise. Estimates of the reliability and validity of the English version of the self-efficacy for exercise (SEE) scale has been widely tested and shown to be valid for use in various settings and among older people. The reliability and validity of a Chinese version of the SEE for older adults has not been tested. AIM To undertake a preliminary assessment of the reliability and validity of the SEE scale when applied to the older Chinese adults. METHODS The Chinese version of the self-efficacy for exercise (SEE-C) scale was tested on a sample of 192 older people from Taiwan with a mean age of 71.2 years recruited between October and December 2003. RESULTS There was acceptable internal consistency of the SEE-C scale. The fit of the measurement model to the data for the SEE-C scale was acceptable. There was evidence of validity of the measure based on hypothesis testing: health status predicted exercise self-efficacy, and exercise self-efficacy predicted physical activity. Those who exercised regularly (n=102) had a higher mean SEE-C score (5.3) than those who did not (2.9, n=90). CONCLUSION This preliminary validation study provided evidence for the reliability and validity of the Chinese version of the SEE scale. Future testing of the SEE-C scale needs to be carried out to see whether these results are generalisable to older Chinese people living in urban areas and with different characteristics. A test of the scale among younger adults for a wider use of the instrument is also warranted.
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Validation Study |
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Psaltis P, Paton S, See F, Arthur A, Martin S, Itescu S, Worthley S, Gronthos S, Zannettino A. Enrichment for STRO-1 expression enhances the cardiovascular paracrine activity of human bone marrow-derived mesenchymal cell populations. J Cell Physiol 2010; 223:530-40. [DOI: 10.1002/jcp.22081] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Caner HH, Kwan AL, Arthur A, Jeng AY, Lappe RW, Kassell NF, Lee KS. Systemic administration of an inhibitor of endothelin-converting enzyme for attenuation of cerebral vasospasm following experimental subarachnoid hemorrhage. J Neurosurg 1996; 85:917-22. [PMID: 8893732 DOI: 10.3171/jns.1996.85.5.0917] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The potent vasoconstrictor peptide, endothelin-1 (ET-1), has been implicated in the pathophysiology of cerebral vasospasm that occurs after subarachnoid hemorrhage (SAH). This peptide is synthesized as a large prepropeptide that requires a series of modifying steps for its activation. The last of these steps involves the proteolytic conversion of a relatively inactive propeptide, Big ET-1, to its active, 21-amino acid peptide form. The enzyme responsible for converting Big ET-1 to ET-1 is a metalloprotease called endothelin-converting enzyme (ECE). In the present study the authors examined the effects of a newly developed inhibitor of ECE on responses to ET peptides in the normal basilar artery and on pathophysiological constriction in the spastic basilar artery after SAH. In the first series of experiments the authors examined normal basilar arteries in the rabbit, which were exposed transclivally and measured on-line using videomicroscopy. Intravenous administration or topical application of an active inhibitor of ECE, CGS 26303, blocked vasoconstrictor responses to topically applied Big ET-1 but not to ET-1. In contrast, topical application of a structurally related compound that does not inhibit ECE, CGS 24592, was ineffective in blocking vasoconstriction that was elicited by a topical application of Big ET-1. These findings indicate that CGS 26303 when administered systemically is capable of blocking the conversion of Big ET-1 to ET-1 in the basilar artery without affecting the ability of the vessel to respond to ET-1. In the second series of experiments the authors examined the effects of the ECE inhibitor on cerebral vasospasm after experimental SAH. Intraperitoneal administration of CGS 26303 via osmotic minipumps significantly attenuated the delayed spastic response of the basilar artery to an intracisternal injection of autologous blood. This study provides the first evidence that systemic administration of an inhibitor of ECE is capable of preventing cerebral vasospasm after SAH. The results reinforce a growing body of evidence that ETs play a critical role in the development of spastic constriction after SAH. Moreover, the findings indicate that blocking the conversion of Big ET-1 to its active ET-1 form using CGS 26303 may represent a feasible strategy for ameliorating cerebral vasospasm.
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