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Background. Oxidative stress is prevalent in dialysis patients and has been implicated in the pathogenesis of cardiovascular disease and anaemia. We conducted a systematic review and meta-analysis to examine the effect of Excebrane, a vitamin E-coated cellulose-based dialyser, on circulating biomarkers of lipid peroxidation, as surrogate markers of oxidative stress.Methods. The primary sources used to identify candidate studies included PubMed, the Cochrane Central Register of Controlled Trials, a bibliography provided by the dialyser manufacturer, and a manual search of abstracts from proceedings of scientific meetings and review articles. Studies were selected for analysis if their design included a comparator group (primarily within patient comparison, i.e. pre- and post-study evaluations). For the meta-analysis, we computed the overall change of the outcome from baseline using a random-effects model. A supplemental analysis was performed in which the absolute levels of these biomarkers of lipid peroxidation were converted to a common unit by calculating standardized effect sizes.Results. Fourteen peer-reviewed articles met the criteria. The studies consisted of 11 single arm, one randomized crossover and two randomized controlled trials, with a total of 37 to 158 evaluable patients, according to the outcome of interest analysed. Due to the paucity of randomized trials, the meta-analysis was limited to the Excebrane arm of each study. When the studies were combined according to similar measurement units, the overall mean decrease in malondialdehyde (MDA) level was -0.3 mM (95% CI, −0.5 to −0.1 mM; seven studies) and −0.8 nmol/mg low-density lipoprotein (LDL) (95% CI, −1.3 to −0.4 nmol/mg LDL; three studies), respectively. The summary estimate revealed a non-significant decrease in pre-dialysis thiobarbituric acid reactive substances (TBARS) level of 0.4 μM (95% CI, −1.2 to 0.4 μM; three studies). When the MDA and TBARS studies were combined using the standardized effect size, the mean decrease in these biomarkers of lipid peroxidation was statistically significant at −1.7 units (95% CI, −2.7, −0.7 units; 13 studies). A meta-analysis on the effect of Excebrane on pre-dialysis levels of oxidized-LDL could not be performed due to study heterogeneity.Conclusion. The conversion of dialysis patients to a vitamin E-coated dialyser is associated with an improvement in circulating biomarkers of lipid peroxidation, which is of potential clinical benefit. [ABSTRACT FROM AUTHOR]

Background. Intensive insulin therapy has been found to reduce mortality in some critically ill patients. We performed a systematic review and meta-analysis to ascertain the effect of intensive insulin therapy on the incidence of acute kidney injury (AKI) in adult critically ill patients. Methods. We searched MEDLINE, SCOPUS and the Cochrane Central Register of Controlled Trials for studies that compared ‘conventional’ vs ‘intensive’ insulin therapy in critically ill patients. Studies were combined with random effects model meta-analyses. Results. Five studies, three of which were randomized controlled trials, reported AKI as a secondary outcome. Two of the studies were non-concurrent prospective cohort studies. All were single-centre studies conducted in intensive care unit settings. By meta-analysis across all studies, intensive insulin therapy reduced the incidence of AKI by 38% [risk ratio (RR) 0.62; 95% confidence interval (CI) 0.47, 0.83; P = 0.001]. The findings of the randomized and cohort studies were similar and the studies were not statistically heterogeneous. Three studies reported the effect of insulin therapy on dialysis requirement. Overall, intensive insulin therapy reduced the incidence of dialysis requirement by 35%, however, this was not statistically significant (RR 0.65; 95% CI 0.40, 1.05; P = 0.08). The overall rate of hypoglycaemia in the conventional insulin therapy group was 1.3% (range 0.3–3.4%). Intensive insulin therapy was associated with a >4-fold increase in the risk of hypoglycaemia (RR 4.5; 95% CI 2.4, 8.5; P < 0.00001) Conclusion. There is evidence that intensive insulin therapy initiated in critically ill adult patients is associated with a reduction in the incidence of AKI in medical and surgical settings. A large trial primarily designed to examine the effect of insulin on the prevention of AKI is needed to confirm this finding. [ABSTRACT FROM AUTHOR]