Murad, M. Hassan

Abstract Mind body therapies appear to reduce morbidity and mortality in patients with cardiovascular diseases, but there is limited understanding of the mechanisms that mediate this effect. Vascular endothelial dysfunction is a central feature of atherogenesis that is adversely impacted by mental stress. We conducted a systematic review and meta-analysis of the effect of mind body therapies on peripheral endothelial function in patients with and without established cardiovascular disease. The search included Medline, Cochrane Library, Scopus and Embase to identify studies up to November 2009. Eligible studies were randomized controlled trials that compared the effects of mind body therapies and placebo on endothelial function. Two reviewers extracted data on study characteristics, methods, and outcomes. Disagreement was resolved by consensus. Three eligible trials enrolled a total of 258 patients. Sixty one (24 percent) were women and 53 percent had established cardiovascular disease. The trials had good methodological quality. Meta-analysis using random-effects model showed a non significant improvement of endothelial function by mind body therapies (standardized mean difference 0.15; 95% CI, -0.36 to 0.67, P=0.56). The analysis was underpowered due to small sample size. Circumstantial evidence indicates that mind body therapies may have a therapeutic benefit on endothelial dysfunction, however, the aggregate data from the three small randomized trials to date do not support this hypothesis. This biologically plausible effect requires additional investigation in adequately powered studies.

Background— Atrial fibrillation (AF) is a common finding in patients with myocardial infarction (MI). Atrial fibrillation is not generally perceived by clinicians as a critical event during the acute phase of MI; however, its prognostic influence in MI remains controversial. Furthermore, contradictory data exist concerning the risk of death according to AF timing. This article, a systematic review and first meta-analysis, aims to quantify the mortality risk associated with AF in MI patients and its timing. Methods and Results— A comprehensive search of several electronic databases (1970 to 2010; adults, any language) identified MI studies that evaluated mortality related to AF. Evidence was reviewed by 2 blinded reviewers with a formal assessment of the methodological quality of the studies. Adjusted odds ratios were pooled across studies using the random-effects model. The I 2 statistic was used to assess heterogeneity. In the 43 included studies (278 854 subjects), the mortality odds ratio associated with AF was 1.46 (95% confidence interval, 1.35 to 1.58; I 2 =76%; 23 studies). This worse prognosis persisted regardless of the timing of AF; the odds ratio of mortality for new AF with no prior history of AF was 1.37 (95% confidence interval, 1.26 to 1.49), I 2 =28%, 9 studies), and for prior AF was 1.28 (95% confidence interval, 1.16 to 1.40; I 2 =24%; 4 studies). The sensitivity analysis of new AF studies adjusting for confounding factors did not show a decrease in risk of death. Conclusions— Atrial fibrillation is associated with increased risk of mortality in MI patients. New AF with no history of AF before MI remained associated with an increased risk of mortality even after adjustment for several important AF risk factors. These subsequent increases in mortality suggest that AF can no longer be considered a nonsevere event during MI.

OBJECTIVE The negative results of two randomized controlled trials (RCTs) have challenged current guideline recommendations for using aspirin for primary prevention of cardiovascular events among patients with diabetes. We therefore sought to determine if the effect of aspirin for primary prevention of cardiovascular events and mortality differs between patients with and without diabetes. RESEARCH DESIGN AND METHODS We conducted a systematic search of MEDLINE, EMBASE, Cochrane Library, Web of Science, and Scopus since their inceptions until November 2008 for RCTs of aspirin for primary prevention of cardiovascular events. Blinded pairs of reviewers evaluated studies and extracted data. Random-effects meta-analysis and Bayesian logistic regression were used to estimate the ratios of relative risks (RRs) of outcomes of interest among patients with and without diabetes. A 95% CI that crosses 1.00 indicates that the effect of aspirin does not differ between patients with and without diabetes. RESULTS Nine RCTs with moderate to high methodological quality contributed data to the analyses. The ratios of RRs comparing the benefit of aspirin among patients with diabetes compared with patients without diabetes for mortality, myocardial infarction, and ischemic stroke were 1.12 (95% CI 0.92–1.35), 1.19 (0.82–1.17), and 0.70 (0.25–1.97), respectively. CONCLUSIONS Whereas estimates of benefit among patients with diabetes remain imprecise, our analysis suggests that the relative benefit of aspirin is similar in patients with and without diabetes.

Abstract Context: Hypoglycemia limits the efficacy of intensive insulin therapy. The extent to which continuous insulin infusion (CSII) overcomes this limitation is unclear. Objective: The aim was to summarize evidence on the effect of CSII and multiple daily injections (MDIs) on glycemic control and hypoglycemia. Data Sources: We searched electronic databases between 2002 and March 2008. Study Selection: We selected published randomized trials of CSII vs. MDI. Data Extraction: Reviewers working in duplicate and independently extracted study characteristics and quality and differences in glycosylated hemoglobin (HbA1c) and hypoglycemic events. Data Synthesis: We found 15 eligible randomized trials of moderate quality, with elevated baseline and end-of-study HbA1c levels. Patients with type 1 diabetes using CSII had slightly lower HbA1c [random-effects weighted mean difference, −0.2%; 95% confidence interval (CI), −0.3, −0.1, compared with MDI], with no significant difference in severe (pooled odds ratio, 0.48; 95% CI, 0.23, 1.00) or nocturnal hypoglycemia (pooled odds ratio 0.82, 95% CI 0.33, 2.03). Adolescents and adults with type 1 diabetes enrolled in crossover trials had nonsignificantly fewer minor hypoglycemia episodes per patient per week (−0.08; 95% CI, −0.21, 0.06) with CSII than MDI; children enrolled in parallel trials had significantly more episodes (0.68; 95% CI, 0.16, 1.20; Pinteraction = 0.03). Outcomes were not different in patients with type 2 diabetes. Conclusions: Contemporary evidence indicates that compared to MDI, CSII slightly reduced HbA1c in adults with type 1 diabetes, with unclear impact on hypoglycemia. In type 2 diabetes, CSII and MDI had similar outcomes. The effect in patients with hypoglycemia unawareness or recurrent severe hypoglycemia remains unclear because of lack of data.

Abstract Context: The diagnosis of Cushing’s syndrome (CS) requires the use of tests of unregulated hypercortisolism that have unclear accuracy. Objective: Our objective was to summarize evidence on the accuracy of common tests for diagnosing CS. Data Sources: We searched electronic databases (MEDLINE, EMBASE, Web of Science, Scopus, and citation search for key articles) from 1975 through September 2007 and sought additional references from experts. Study Selection: Eligible studies reported on the accuracy of urinary free cortisol (UFC), dexamethasone suppression test (DST), and midnight cortisol assays vs. reference standard in patients suspected of CS. Data Extraction: Reviewers working in duplicate and independently extracted study characteristics and quality and data to estimate the likelihood ratio (LR) and the 95% confidence interval (CI) for each result. Data Synthesis: We found 27 eligible studies, with a high prevalence [794 (9.2%) of 8631 patients had CS] and severity of CS. The tests had similar accuracy: UFC (n = 14 studies; LR+ 10.6, CI 5.5–20.5; LR− 0.16, CI 0.08–0.33), salivary midnight cortisol (n = 4; LR+ 8.8, CI 3.5–21.8; LR− 0.07, CI 0–1.2), and the 1-mg overnight DST (n = 14; LR+ 16.4, CI 9.3–28.8; LR− 0.06, CI 0.03–0.14). Combined testing strategies (e.g. a positive result in both UFC and 1-mg overnight DST) had similar diagnostic accuracy (n = 3; LR+ 15.4, CI 0.7–358; LR− 0.11, CI 0.007–1.57). Conclusions: Commonly used tests to diagnose CS appear highly accurate in referral practices with samples enriched with patients with CS. Their performance in usual clinical practice remains unclear.