6 resultados para Pooled analysis
em Aston University Research Archive
Resumo:
Purpose: Atrial fibrillation (AF) is the most common heart arrhythmia and is associated with an increased risk of stroke. Stroke risk is commonly treated with oral anticoagulation (OAC) with a narrow therapeutic range (INR 2.0 to 3.0); which is poorly controlled in practice. Barriers to adherence include poor knowledge, and inaccurate perceptions surrounding illness and medications. Trial registration: ISRCTN93952605. Systematic review: Seven trials of educational, self-monitoring and decision aid interventions were included in a systematic review. Pooled analysis suggested education OR, 95% CI 7.89 (5.54-10.24) and self monitoring OR (95% CI) 5.47(2.55-8.39) significantly improve TTR; whereas decision aids are no more effective in reducing decision conflict than usual care, OR (95% CI) -0.10 (-0.17 to -0.02). Intervention development: The intervention was theoretically-driven (utilising the common sense and beliefs about medication models) and developed with expert patient feedback. Described using behavioural change techniques, the one-off group session included an educational booklet, ‘expert-patient’ focussed DVD, and worksheet. Methods: Ninety seven warfarin-naïve AF patients were randomised to receive the intervention (n=43), or usual care (n=54). The primary endpoint was time within therapeutic range (TTR), secondary endpoints included knowledge, quality of life (AF-QoL-18), beliefs about medication (BMQ), illness perceptions (IPQ-B), and anxiety and depression (HADS). Results: Intervention group had significantly higher TTR than usual care (78.5% vs. 66.7%; p=0.01). Knowledge changed significantly across time (F (3, 47) = 6.4; p<0.01), but not between groups (F (1, 47) = 3.3; p = 0.07). At six months knowledge predicted TTR (r=0.245; p=0.04). Illness concern negatively correlated with TTR (r= - 0.199; p=0.05). General Harm scores at one month predicted TTR (F (1, 72) = 4.08; p=0.048). There were significant differences in emotional representations (F (3, 49) = 3.3 (3, 49); p= 0.03), anxiety (F (3, 46) = 25.2; p<0.01) and depression (F (3, 46) = 37.7; p<0.01) across time. Conclusion: A theory-driven educational intervention can improve TTR in AF patients and potentially reduce the risk of adverse clinical outcomes. Improving education provision for AF patients is essential to ensure efficacious treatment.
Resumo:
This paper examines the source country determinants of FDI into Japan. The paper highlights certain methodological and theoretical weaknesses in the previous literature and offers some explanations for hitherto ambiguous results. Specifically, the paper highlights the importance of panel data analysis, and the identification of fixed effects in the analysis rather than simply pooling the data. Indeed, we argue that many of the results reported elsewhere are a feature of this mis-specification. To this end, pooled, fixed effects and random effects estimates are compared. The results suggest that FDI into Japan is inversely related to trade flows, such that trade and FDI are substitutes. Moreover, the results also suggest that FDI increases with home country political and economic stability. The paper also shows that previously reported results, regarding the importance of exchange rates, relative borrowing costs and labour costs in explaining FDI flows, are sensitive to the econometric specification and estimation approach. The paper also discusses the importance of these results within a policy context. In recent years Japan has sought to attract FDI, though many firms still complain of barriers to inward investment penetration in Japan. The results show that cultural and geographic distance are only of marginal importance in explaining FDI, and that the results are consistent with the market-seeking explanation of FDI. As such, the attitude to risk in the source country is strongly related to the size of FDI flows to Japan. © 2007 The Authors Journal compilation © 2007 Blackwell Publishing Ltd.
Resumo:
The term "pharmacogenetics" has been defined as the scientific study of inherited factors that affect the human drug response. Many pharmacogenetie studies have been published since 1995 and have focussed on the principal enzyme family involved in drug metabolism, the cytochrome P450 family, particularly cytochrome P4502C9 and 2C19. In order to investigate the pharmacogenetic aspect of pharmacotherapy, the relevant studies describing the association of pharmacogenetic factor(s) in drug responses must be retrieved from existing literature using a systematic review approach. In addition, the estimation of variant allele prevalence for the gene under study between different ethnic populations is important for pharmacogenetic studies. In this thesis, the prevalence of CYP2C9/2C19 alleles between different ethnicities has been estimated through meta-analysis and the population genetic principle. The clinical outcome of CYP2C9/2C19 allelic variation on the pharmacotherapy of epilepsy has been investigated; although many new antiepileptic drugs have been launched into the market, carbamazepine, phenobarbital and phenytoin are still the major agents in the pharmacotherapy of epilepsy. Therefore, phenytoin was chosen as a model AED and the effect of CYP2C9/2C19 genetic polymorphism on phenytoin metabolism was further examined.An estimation of the allele prevalence was undertaken for three CYP2C9/2C19 alleles respectively using a meta-analysis of studies that fit the Hardy-Weinberg equilibrium. The prevalence of CYP2C9*1 is approximately 81%, 96%, 97% and 94% in Caucasian, Chinese, Japanese, African populations respectively; the pooled prevalence of CYP2C19*1 is about 86%, 57%, 58% and 85% in these ethnic populations respectively. However, the studies of association between CYP2C9/2C19 polymorphism and phenytoin metabolism failed to achieve any qualitative or quantitative conclusion. Therefore, mephenytoin metabolism was examined as a probe drug for association between CYP2C19 polymorphism and mephenytoin metabolic ratio. Similarly, analysis of association between CYP2C9 polymorphism and warfarin dose requirement was undertaken.It was confirmed that subjects carrying two mutated CYP2C19 alleles have higher S/R mephenytoin ratio due to deficient CYP2C19 enzyme activity. The studies of warfarin and CYP2C9 polymorphism did not provide a conclusive result due to poor comparability between studies.The genetic polymorphism of drug metabolism enzymes has been studied extensively, however other genetic factors, such as multiple drug resistance genes (MDR) and genes encoding ion channels, which may contribute to variability in function of drug transporters and targets, require more attention in future pharmacogenetic studies of antiepileptic drugs.
Resumo:
Objective: To determine the efficacy of cholinesterase inhibitors (ChEIs) in improving the behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer’s disease (AD). Data sources: We searched MEDLINE, Cochrane Registry, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from 1966 to 2007. We limited our search to English Language, full text, published articles and human studies. Data extraction: We included randomized, double-blind, placebo-controlled trials evaluating the efficacy of donepezil, rivastigmine, or galantamine in managing BPSD displayed by AD patients. Using the United States Preventive Services Task Force (USPSTF) guidelines, we critically appraised all studies and included only those with an attrition rate of less than 40%, concealed measurement of the outcomes, and intention to treat analysis of the collected data. All data were imputed into pre-defined evidence based tables and were pooled using the Review Manager 4.2.1 software for data synthesis. Results: We found 12 studies that met our inclusion criteria but only nine of them provided sufficient data for the meta-analysis. Among patients with mild to severe AD and in comparison to placebo, ChEIs as a class had a beneficial effects on reducing BPSD with a standard mean difference (SMD) of -0.10 (95% confidence interval [CI]; -0.18, -0.01) and a weighted mean difference (WMD) of -1.38 neuropsychiatry inventory point (95% CI; -2.30, -0.46). In studies with mild AD patients, the WMD was -1.92 (95% CI; -3.18, -0.66); and in studies with severe AD patients, the WMD was -0.06 (95% CI; -2.12, +0.57). Conclusion: Cholinesterase inhibitors lead to a statistical significant reduction in BPSD among patients with AD, yet the clinical relevance of this effect remains unclear.
Resumo:
Objectives: Are behavioural interventions effective in reducing the rate of sexually transmitted infections (STIs) among genitourinary medicine (GUM) clinic patients? Design: Systematic review and meta-analysis of published articles. Data sources: Medline, CINAHL, Embase, PsychINFO, Applied Social Sciences Index and Abstracts, Cochrane Library Controlled Clinical Trials Register, National Research Register (1966 to January 2004). Review methods: Randomised controlled trials of behavioural interventions in sexual health clinic patients were included if they reported change to STI rates or self reported sexual behaviour. Trial quality was assessed using the Jadad score and results pooled using random effects meta-analyses where outcomes were consistent across studies. Results: 14 trials were included; 12 based in the United States. Experimental interventions were heterogeneous and most control interventions were more structured than typical UK care. Eight trials reported data on laboratory confirmed infections, of which four observed a greater reduction in their intervention groups (in two cases this result was statistically significant, p<0.05). Seven trials reported consistent condom use, of which six observed a greater increase among their intervention subjects. Results for other measures of sexual behaviour were inconsistent. Success in reducing STIs was related to trial quality, use of social cognition models, and formative research in the target population. However, effectiveness was not related to intervention format or length. Conclusions: While results were heterogeneous, several trials observed reductions in STI rates. The most effective interventions were developed through extensive formative research. These findings should encourage further research in the United Kingdom where new approaches to preventing STIs are urgently required.
Resumo:
INTRODUCTION: Statin use inadvertently during pregnancy and proposed use of statins for the treatment of preeclampsia, led us to question the evidence behind their current contraindicated status. Several studies have evaluated the relationship between statin use in pregnancy with fetal outcome but their results have not been quantitatively assessed by meta-analysis. Our objective was to undertake a systematic review of all published clinical evidence to assess the effects of statin use in pregnancy on subsequent fetal wellbeing. METHODS: A comprehensive search strategy was performed of all electronic databases and the Merck reporting database for studies published from 1966 to 2014. Two reviewers independently screened citations and undertook study quality assessment and data extraction. We obtained summary estimates of adverse fetal events that were classified as potentially fatal, clinically significant morbidity or minor adverse event. We identified 602 titles and reviewed 30 articles for inclusion and exclusion criteria. Meta-analysis was performed on seven studies (3 cohort, 3 case-series and 1 case-control). RESULTS: Of the 922 cases of statin exposure in pregnancy, 27 exposures were associated with lethal or clinically significant fetal morbidity and 10 with minor adverse events. Statin exposure was limited to the first trimester in all but two cases. The pooled rate of lethal or clinically significant fetal abnormalities in pregnant women exposed to statins was 0.01 (95% CI 0.00-0.04), less than the European rate of 0.026 (95% CI 2.54- 2.57)EUROCAT. The rate of fetal abnormality for simvastatin was 0.03 (95% CI 0.00-0.08), atorvostatin 0.11 (95% CI 0.00-0.52), pravastatin 0.01 (95% CI 0.00-0.2) and lovastatin use 0.04 (95% CI 0.00-0.28). Systems based anomalies were also calculated, congenital heart disease was 0.8 (95% CI 0.02-0.12) compared with the background rate of 0.79 (95% CI 0.78- 0.80). CONCLUSIONS: The published data suggests that statins may not be teratogenic when given inadvertently during pregnancy and prospective studies such as The StAmP Trial may provide more data