Meta-analysis studies cardiovascular disease

Stampfer MJ, Willett WC, Colditz GA, Speizer FE, Hennekens CH. Past use of oral contraceptives and cardiovascular disease a meta-analysis in the context of the Nurses Health Study. Am J Obstet Gynecol 1990 163(1 Pt 2) 285-91. 

Siri-Tarino, P. W., Sun, Q., Hu, F. B., and Krauss, R. M. (2010). Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am. J. Clin. Nutr. 91, 535-546. 

In case LDL oxidation is considered as an important risk factor, the dosage of vitamin E may be important to determine a clinical effect. However, with respect to inhibition of protein kinase-C and the release of proinflammatory cytokines the intracellular transfer of RRRT (natural vitamin E) by the tocopherol-associated protein may be a crucial point. Consequently, natural vitamin E is considered more effective than the synthetic one. Since the activity on LDL oxidation was pointed out as important for the prevention of cardiovascular disease, most of the long-term trials with vitamin E were conducted at dosages >200 mg/day (about 200 lU/d). In a recent meta-analysis the association of plasma levels and mortality was studied in 1168 elderly European men and women (25). No association was found between the plasma concentration and all-cause or cause-specific mortality. 

Danesh J, Whincup P, Walker M et al. (2000). Chlamydia pneumoniae IgG litres and coronary heart disease prospective study and metaanalysis. British Medical Journal 321 208-213 Danesh J, Whincup P, Walker M (2003). Chlamydia pneumoniae IgA litres and coronary heart disease prospective study and meta-analysis. European Heart Journal 24 881 Danesh J, Lewington S, Thompson SG et al. (2005). Plasma fibrinogen level and the risk of major cardiovascular diseases and non-vascular mortality an individual participant meta-analysis. Journal of American Medical Association 294 1799-1809 Diabetes Control and Complications Trial/ Epidemiology of Diabetes Interventions and Complications Research Group (2003). 

Casas JP, Hingorani AD, Bautista LE et al. (2004). Meta-analysis of genetic studies in ischemic stroke thirty-two genes involving approximately 18 000 cases and 58 000 controls. Archives of Neurology 61 1652-1661 Casas JP, Cavalleri CL, Bautista LE et al. (2006). Endothelial nitric oxide synthase gene polymorphisms and cardiovascular disease ... 

Erkkila AT, Lehto S, Pyorala K, Uusitupa MI. n-3 fatty acids and 5-y risks of death and cardiovascular disease events in patients with coronary artery disease. Am. J. CUn. Nutr. 2003 78 65-71. He K, Song Y, Daviglus ML, Liu K, Van Horn L, Dyer AR, Greenland P. Accumulated evidence on fish consumption and coronary heart disease mortaUty a meta-analysis of cohort studies. Circulation 2004 109 2705-2711. 

The best overall evidence of the safety of diuretics in old people comes from the large-scale outcome trials in hypertensive patients (11,13,15,17,18). These studies in over 10000 subjects aged over 60 years showed clearly that thiazide-based treatment reduces the risk of stroke, coronary heart disease events, and cardiovascular events in older hypertensive patients. A meta-analysis (163) of randomized trials lasting at least 1 year and involving 16164 individuals aged at least 60 years showed that diuretics were superior to beta-blockers with regard to all endpoints (stroke, coronary heart disease events, cardiovascular mortality, and all-cause mortality). The beneficial effects noted in these trials should dispel any doubts about the safety and efficacy of diuretics in old people. 

Elevated serum cholesterol levels and in particular LDL-cholesterol levels are strongly associated with cardiovascular mortality across the spectrum of epidemiologic studies and pharmacologic intervention studies in primary and secondary prevention trials (Ligure 4.4). In the Cholesterol Treatment Trialists Collaborators meta-analysis of >90,000 patients studied in 14 randomized trials of statin therapy, a reduction in LDL cholesterol of 1 mmol/L (39 mg/dL) was associated with a 12% proportional reduction in all-cause mortality, predominantly driven by a 19% proportional reduction in cardiovascular mortality (45). Among patients with pre-existing heart disease there were 14 fewer deaths per 1000 participants per mmol LDL cholesterol reduction, as well as an approximately 25% reduction in major adverse cardiac events. 

The healthy value of the MeD has from one side been attributed to its cardio-protective effects. The number of publications on this topic was large enough to allow a meta-analysis published by Sofi et al. in 2008. The studies included prospectively analyzed the association between adherence to MeD, mortality and incidence of diseases 12 studies, with a total of 1,574,299 subjects followed for a time ranging from three to 18 years were included. Data evaluating cardiovascular mortality in relation to MeD using dietary scores came from four studies including a total of 404,491 subjects and 3876 fatal events. Results supported the association of a two-point increase in the score indexes was associated with 9% reduction in mortality from CVDs. 

The subsequent evidence from the Homocysteine Studies Collaboration meta-analysis demonstrated the importance of homocysteine for cardiovascular risk was much less extreme than had been previously believed (Table 45.1). The Homocysteine Studies Collaboration meta-analysis did not adjust for the effects of creatinine, as these data were not available, and so was unable to assess the extent to which the assodation of homocysteine with vascular disease could have been confounded by renal function. 

Although the observational studies suggested modest associations of homocysteine with risk of vascular disease that were biologically plausible, such studies could not establish if these associations were causal. The randomized trials assessed the effectiveness of dietary supplementation with B vitamins to lower homocysteine levels on risk of cardiovascular morbidity and mortality. The initial trials were designed in the mid-1990s before the results of the Homocysteine Studies Collaboration meta-analysis (Homocysteine Studies Collaboration 2002) were reported in 2002. Consequently, few of the individual trials had sufficient statistical power to confirm or refute the 10% difference in... 

Currently, the most important factor is the nonrandomized clinical trial outcomes with tea. Epidemiological studies of tea are manifestly confused by the lifestyles of tea drinkers and nontea drinkers, background tea intake of the population, quality and quantity of the tea, among other factors. Considering the particular example of cardiovascular disease, the drug recommendation for its treatment is based on randomized clinical trials and meta-analysis of clinical trials. In studies with particular drugs, the control group can be randomized for zero... 

Cardiovascular The risk of cardiovascular disease from antiretroviral therapy for HIV was reviewed in a metaanalysis and systematic review [290 ]. Twenty-seven studies met the inclusion criteria and eight contributed to a formal meta-analysis with the final outcomes of myocardial infarction (MI), stroke and other cardiovascular events. Findings based on two observational studies indicated an increase in risk of MI for patients exposed to ABC (RR 1.92,95% Cl 1.51-2.42) and PI (RR 2.13,95% Cl 1.06-4.28), specifically indinavir (IDV) (RR 1.11,95% Cl 1.05-1.17) and LPV (RR 1.22, 95% Cl 1.01-1.47). As these results are in contrast to four published meta-analyses, further investigation is needed. 

The efficacy and safety of paricalcitol therapy in the management of chronic kidney disease has been evaluated. Nine studies with a total of 832 participants were included. There was no significant difference in the risk of hypercalcaemia between paricalcitol and control groups (RR=2.25 95% Cl 0.81-6.26 P = 0.12). Paricalcitol therapy was not associated with a significantly increased risk of cardiovascular and endocrine adverse events compared with controls (RR 1.07 95% Cl 0.84-1.36 P=0.58) [76 ]. No serious adverse events were reported in a meta-analysis of 12 studies examining the impact of vitamin D supplementation on chronic kidney disease in non-dialysis patients [77 ]. 

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