Article

Ye, Z. & Song, H. Antioxidant vitamins intake and the risk of coronary heart disease: meta-analysis of cohort studies. Eur. J. Cardiovasc. Prev. Rehabil. 15, 26-34

Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
European Journal of Cardiovascular Prevention and Rehabilitation (Impact Factor: 3.69). 03/2008; 15(1):26-34. DOI: 10.1097/HJR.0b013e3282f11f95
Source: PubMed

ABSTRACT

Many epidemiological studies have reported that antioxidant vitamin intake from diet or supplements are associated with a lower risk of coronary heart disease (CHD), the findings are, however, inconsistent. We undertook a meta-analysis of cohort studies to examine the relations between antioxidant vitamins (vitamins C, E, and beta-carotene) and CHD risk.
We included all the relevant cohort studies if they provided a relative risk and corresponding 95% confidence interval (CI) of CHD in relation to antioxidant vitamins intake from diet or supplement. Fifteen cohort studies were identified involving a total of 7415 incident CHD cases and 374,488 participants with a median follow-up of approximately 10, 8.5, and 15 years for vitamins C, E, and beta-carotene, respectively. Pooled estimates across studies were obtained by random-effects model. The potential sources of heterogeneity and publication bias were also estimated. For vitamins C, E, and beta-carotene, a comparison of individuals in the top third with those in the bottom third of baseline value yielded a combined relative risk of 0.84 (95% CI, 0.73-0.95), 0.76 (95% CI, 0.63-0.89), and 0.78 (95% CI, 0.53-1.04), respectively. Subgroup analyses show that dietary intake of vitamins C and E and supplement use of vitamin E have an inverse association with CHD risk, but supplement use of vitamin C has no significant association with CHD risk. In the dose-response meta-analysis, each 30 mg/day increase in vitamin C, 30 IU/day increase in vitamin E, and 1 mg/day increase in beta-carotene yielded the estimated overall relative risk for CHD of 1.01 (95% CI, 0.99-1.02), 0.96 (95% CI, 0.94-0.99), and 1.00 (95% CI, 0.88-1.14), respectively.
Our findings in this meta-analysis suggest that an increase in dietary intake of antioxidant vitamins has encouraging prospects for possible CHD prevention.

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    • "Instead, precise measurement of specific compounds is recommended. Regarding the " pro " #5, the situation does not seem entirely clear, as some published metastudies related to protective role of vitamin C in coronary heart disease showed some contradictions (better protection with dietary vitamin C versus synthetic vitamin C) (Ye and Song [23]; Knekt et al. [24]). "
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    ABSTRACT: Many 1,4-dihydropyridines (DHPs) possess redox properties. In this review DHPs are surveyed as protectors against oxidative stress (OS) and related disorders, considering the DHPs as specific group of potential antioxidants with bioprotective capacities. They have several peculiarities related to antioxidant activity (AOA). Several commercially available calcium antagonist, 1,4-DHP drugs, their metabolites, and calcium agonists were shown to express AOA. Synthesis, hydrogen donor properties, AOA, and methods and approaches used to reveal biological activities of various groups of 1,4-DHPs are presented. Examples of DHPs antioxidant activities and protective effects of DHPs against OS induced damage in low density lipoproteins (LDL), mitochondria, microsomes, isolated cells, and cell cultures are highlighted. Comparison of the AOA of different DHPs and other antioxidants is also given. According to the data presented, the DHPs might be considered as bellwether among synthetic compounds targeting OS and potential pharmacological model compounds targeting oxidative stress important for medicinal chemistry.
    Full-text · Article · Jan 2016 · Oxidative medicine and cellular longevity
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    • "The first report on efficacy of antioxidants on cardiovascular events in coronary artery disease patients [106] was later confirmed by further studies [107–110] (Table 3), but numerous subsequent randomized clinical trials failed to prove any benefit [111–126] (Table 4). Moreover, meta-analyses on this issue are discordant [127, 128]. "
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    • "Interestingly, this is not what is reported for subjects without diabetes2,17. A systematic review of 15 cohort studies with 374,488 subjects without DM showed an inverse association between higher intake of vitamin C (diet and supplement) and risk of coronary artery disease (RR 0.84; 95%CI 0.73-0.95)2, but the results were not confirmed with the use of supplemental vitamin C only in the same study2. "
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    ABSTRACT: Inverse associations between micronutrient intake and cardiovascular outcomes have been previously shown, but did not focus on diabetic patients. To systematically review the role of micronutrients in the development/presence of cardiovascular outcomes in patients with diabetes. We searched Medline, Embase, and Scopus (January/1949-March/2012) for observational studies that evaluated micronutrients and cardiovascular outcomes in patients with diabetes, and then selected and extracted the data (two independent reviewers). From the 15 658 studies identified, five were included, comprising three case-control and two cohorts, with a follow-up of 7-15 years. A meta-analysis was not performed due to the different antioxidant micronutrients (types and measurement methods) and outcomes evaluated. The micronutrients assessed were vitamin C intake in diet and/or supplementation, chromium and selenium in toenail samples, and α-tocopherol and zinc in serum levels. Intake of >300 mg of vitamin C through supplementation was associated with increased risk of cardiovascular disease, coronary artery disease (CAD), and stroke (RR 1.69-2.37). High levels of α-tocopherol in serum were associated with 30% lower CAD risk in another study (HR 0.71; 95%CI 0.53-0.94). Among minerals (zinc, selenium, and chromium), an inverse association between zinc and CAD was observed; levels lower than 14.1 µmol/L were associated with an increased risk for CAD (RR 1.70; 95%CI 1.21-2.38). The information available on this issue is scarce. Further prospective studies are needed to elucidate the role of these nutrients in the cardiovascular risk of patients with diabetes.
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