41 research outputs found

    Influence of Calendar Period on the Association Between BMI and Coronary Heart Disease: A Meta-Analysis of 31 Cohorts

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    Objective: The association between obesity and coronary heart disease (CHD) may have changed over time, for example due to improved pharmacological treatment of CHD risk factors. This meta-analysis of 31 prospective cohort studies explores the influence of calendar period on CHD risk associated with body mass index (BMI). Design and Methods: The relative risks (RRs) of CHD for a five-BMI-unit increment and BMI categories were pooled by means of random effects models. Meta-regression analysis was used to examine the influence of calendar period (>1985 v 1985) in univariate and multivariate analyses (including mean population age as a covariate). Results: The age, sex, and smoking adjusted RR (95% confidence intervals) of CHD for a five-BMI-unit increment was 1.28(1.22:1.34). For underweight, overweight and obesity, the RRs (compared to normal weight) were 1.11(0.91:1.36), 1.31(1.22:1.41), and 1.78(1.55:2.04), respectively. The univariate analysis indicated 31% (95%CI: 56:0) lower RR of CHD associated with a five-BMI-unit increment and a 51% (95%CI: 78: 14)) lower RR associated with obesity in studies starting after 1985 (n ¼ 15 and 10, respectively) compared to studies starting in or before 1985 (n ¼ 16 and 10). However, in the multivariate analysis, only mean population age was independently associated with the RRs for a five-BMI-unit increment and obesity ( 29(95%CI: 55: 5)) and 31(95%CI: 66:3), respectively) per 10-year increment in mean age). Conclusion: This study provides no consistent evidence for a difference in the association between BMI and CHD by calendar period. The mean population age seems to be the most important factor that modifies the association between the risk of CHD and BMI, in which the RR decreases with increasing age

    Systematically missing confounders in individual participant data meta-analysis of observational cohort studies.

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    One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154,012 participants in 31 cohort

    Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

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    The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

    Reactions of pulmonary emphysema patients before and after VRS - Forcusing on the rehabilitation, activity, surgery -

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    今まで内科的治療が主体であった肺気腫に対して,近年外科的治療(Volume Reduction Surgery 以後VRSと略す)が行われるようになった。VRSを受ける患者の看護では,手術前後において, リハビリテーション(以後リハビリと略す)や機能回復に向けてのケアが必要不可欠とされる。そこで,本研究は肺気腫患者の適切な看護援助を検討するために,手術前後に示す肺気腫患者のリハビリや活動に対する反応を明らかにすることを目的とした。対象者は当病棟に入院している肺気腫患者8名(VRS手術前8名,手術後はそのうちの6名である)で, リハビリ, 日常生活活動,呼吸,手術などについて,面接ならびに観察による調査を行った。分析の結果,手術前においてリハビリでは≪義務感≫,頑張って行えば呼吸が楽になるという≪期待感≫,≪サポート≫,≪不安≫が,活動では≪活動の制限≫,手術では呼吸が楽になるのではという≪期待感≫,≪おまかせ≫,≪いちかばちかの賭け≫,≪不安≫,≪回復に向けての欲求の高まり≫が明らかになった。手術後においてリハビリでは≪呼吸が楽になるための手段≫が, 日常生活活動では≪今の状態よりは良くなると いう期待感≫が,手術では≪達成感≫ と≪身体的苦痛≫が,将来については≪ささやかな欲求≫が明らかになった。Pulmonary emphysema has been mainly treated with medicine, but recently VRS(volume reduction surgery) has been receiving much attention. In nursing care for VRS patients, it is important to help the patient improve his/her daily activities and recover physical function smoothly after surgery. The purpose of this study is to clarify the reactions of pulmonary emphysema patients before and after VRS for appropriate nursing. The subjects were eight pulmonary emphysema patients at a ward in Okayama University Hospital, but six of them completed both before and after VRS data collection. The data were collected by interview and observation, and from medical and nursing records. Contents of the interview included rehabilitation, daily activities, respiratory symptoms, operative stress, and so on. The results were as follows : , , , and on rehabilitation, on activity, , , , , and on surgery were extracted as pre-operative patients's reactions. on rehabilitation, on activity, and on surgery, on future were extracted as post-operative patients's reactions
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