Arch Intern Med issue: pdfs availed, free DASH paper

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Hi All, The free full-text (1) paper on the DASH diet from the current Archives of Internal Medicine issue was among the pdf-availed papers. The (2,3) comments regarding the paper PMID: 17698683 http://tinyurl.com/4a74mh were also noted. Contents in the current issue of the journal can be viewed at: http://archinte.ama-assn.org/current.dtl In This Issue of Archives of Internal Medicine 1. Adherence to a DASH-Style Diet and Risk of Coronary Heart Disease and Stroke in Women T. Fung; E. Chiuve; Marjorie L. McCullough; M. Rexrode; Giancarlo Logroscino; B. HuArch Intern Med. 2008;168(7):713-720.http://archinte.ama-assn.org/cgi/content/full/168/7/713http://archinte.ama-assn.org/cgi/reprint/168/7/713 ABSTRACT Background The Dietary Approaches to Stop Hypertension (DASH) diet has been shown to lower blood pressure, but little is known about its long-term effect on cardiovascular end points. Our objective was to assess the association between a DASH-style diet adherence score and risk of coronary heart disease (CHD) and stroke in women. Methods In this prospective cohort study, diet was assessed 7 times during 24 years of follow-up (1980-2004) with validated food frequency questionnaires. A DASH score based on 8 food and nutrient components (fruits, vegetables, whole grains, nuts and legumes, low-fat dairy, red and

processed meats, sweetened beverages, and sodium) was calculated. Lifestyle and medical information was collected biennially with a questionnaire. The proportional hazard model was used to adjust for potential confounders. The study population comprised 88 517 female nurses aged 34 to 59 years without a history of cardiovascular disease or diabetes in 1980. The main outcome measures were the numbers of confirmed incident cases of nonfatal myocardial infarction, CHD death, and stroke. Results We documented 2129 cases of incident nonfatal myocardial infarction, 976 CHD deaths, and 3105 cases of stroke. After adjustment for age, smoking, and other cardiovascular risk factors, the relative risks of CHD across quintiles of the DASH score were 1.0, 0.99, 0.86, 0.87, and 0.76 (95% confidence interval, 0.67-0.85) (P < .001 for trend). The magnitude of risk difference was similar for nonfatal myocardial infarction and fatal CHD. The DASH

score was also significantly associated with lower risk of stroke (multivariate relative risks across quintiles of the DASH score were 1.0, 0.92, 0.91, 0.89, and 0.82) (P = .002 for trend). Cross-sectional analysis in a subgroup of women with blood samples showed that the DASH score was significantly associated with lower plasma levels of C-reactive protein (P = .008 for trend) and interleukin 6 (P = .04 for trend). Conclusion Adherence to the DASH-style diet is associated with a lower risk of CHD and stroke among middle-aged women during 24 years of follow-up. 2. Niki Katsiki; Christos Manes. Arch Intern Med. 2008;168(7):773. COMMENTS & OPINIONS Clinical Trials of Antioxidant Supplementation in the Prevention of Cardiovascular Events. The Women's Antioxidant Cardiovascular Study (WACS) was conducted to evaluate the effects of antioxidant vitamins

on the risk of cardiovascular events.1 Regarding the limitations of this study, apart from the lack of complete follow-up and compliance reported by the authors, some other points should have been discussed. First, only women were included in the trial. No information about premenopausal or postmenopausal status of the study population was given. Moreover, dietary habits of the participants were not taken into account, despite the fact that antioxidant clinical studies should investigate the impact of a rich-in-antioxidant-nutrients diet in conjunction with the administration of vitamin supplements, as mentioned in the introduction. Furthermore, the dose of vitamin E (600 IU every other day) may be responsible for the observed neutral results, since it is lower than the one (400 or 600 IU/d) used in the majority of the antioxidant trials, some of which report positive results.2-3 In addition, this is the first study to report vitamin E

supplementation every other day, and this point should have been discussed. It is thought by Jialal and Devaraj4 that there is a threshold dose of vitamin E that might be effective, and that dose was stated to be 800 IU/d. The findings of the WACS were consistent with the literature, since they reported no overall effect of vitamin C, vitamin E, or beta carotene, alone or in combination, on the primary or secondary outcomes of myocardial infarction, stroke, coronary revascularization, or cardiovascular disease death. No detrimental effects of any of the supplements on total or cardiovascular disease mortality were reported. Interestingly, a significant reduction in the primary end point in the subgroup of women with prior cardiovascular disease was observed (P = .04), possibly suggesting that those participants with elevated levels of oxidative stress may benefit more from antioxidant supplementation. This

finding was in accordance with the results reported by Fang et al5 and those of other prospective randomized controlled clinical trials (Cambridge Heart Antioxidant Study [CHAOS], Secondary Prevention with Antioxidants of Cardiovascular Disease in End-stage Renal Disease [sPACE], Indian Experiment of Infarct Survival Study—3 [iEISS], and Cholesterol Lowering Atherosclerosis Study [CLAS]) showing that the administration of antioxidants reduced the risk of cardiovascular disease. It should be pointed out that another trial (Antioxidant Supplementation in Atherosclerosis Prevention [ASAP]6) evaluated the effect of vitamin E and C supplementation, alone or in combination, on the progression of carotid atherosclerosis. The proportion of men with progression but not of postmenopausal women with progression was reduced by 74% (P = .003) in the combination group compared with the placebo group. Finally, WACS was the

first trial to our knowledge to report fewer strokes in those randomized to both active ascorbic acid and vitamin E supplementation (P = .03). REFERENCES 1. Cook NR, Albert CM, Gaziano JM, Zaharris E, MacFadyen J, son E, Buring JE, Manson JE.A randomized factorial trial of vitamins C and E and beta carotene in the secondary prevention of cardiovascular events in women: results from the Women's Antioxidant Cardiovascular Study.Arch Intern Med. 2007 Aug 13-27;167(15):1610-8. PMID: 17698683 http://tinyurl.com/4a74mh2. Kritharides L, Stocker R. The use of antioxidant supplements in coronary heart disease. Atherosclerosis. 2002;164(2):211-219. FULL TEXT | ISI | PUBMED 3. Eidelman RS, Hollar D, Hebert PR, Lamas GA, Hennekens CH. Randomized trials of vitamin E in the treatment and prevention of cardiovascular disease. Arch Intern Med.

2004;164(14):1552-1556. FREE FULL TEXT 4. Jialal I, Devaraj S. Antioxidants and atherosclerosis: don't throw out the baby with the bath water. Circulation. 2003;107(7):926-928. FULL TEXT | ISI | PUBMED 5. Fang JC, Kinlay S, Beltrame J; et al. Effect of vitamins C and E on progression of transplant-associated arteriosclerosis: a randomised trial. Lancet. 2002;359(9312):1108-1113. FULL TEXT | ISI | PUBMED 6. Salonen JT, Nyyssonen K, Salonen R; et al. Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study: a randomized trial of the effect of vitamins E and C on 3-year progression of carotid atherosclerosis. J Intern Med. 2000;248(5):377-386. FULL TEXT | ISI | PUBMED 3. RELATED LETTER Clinical Trials of Antioxidant Supplementation in the Prevention of Cardiovascular Events—Reply R. Cook, M. Albert, JoAnn E. Manson, and for the WACS Investigator Group

Arch Intern Med. 2008;168(7):773-774. In reply We thank Katsiki and Manes for their interest in our study,1 which addresses the role of antioxidant vitamins, alone and in combination, in the prevention of cardiovascular events. Although our trial included only women, several antioxidant trials have been conducted in men or women separately, with similar results.2 We note that we provided information about the menopausal status of the study population in our article; this information is presented in Table 1, with subgroup effects by menopausal status given in Table 3.1 Participants in WACS represent a relatively well-nourished population of female health professionals. Women in the trial were asked to avoid taking supplements above the recommended daily allowance for these agents. The prevalence of multivitamin use at baseline is presented in

Table 11 and was similar across randomized treatment groups. While we did not explicitly examine effects by baseline dietary composition, we would expect that dietary habits also would be evenly distributed by intervention group owing to the randomization. This should minimize any confounding by baseline diet. Although effect modification by dietary intake cannot be ruled out, Table 31 indicates no appreciable effect modification by baseline multivitamin use. The dose of 600 IU administered every other day is more than 10 times higher than the recommended daily allowance. This is the same dosing regimen used in the recent Women's Health Study3 and should be adequate to inhibit low-density lipoprotein oxidation. Observational studies, such as the Nurses' Health Study, have, in fact, suggested coronary benefits at doses of 100 IU/d of vitamin E.4 While it is possible that higher doses may be more effective, other secondary prevention trials

with doses of 600 to 800 IU/d have yielded inconsistent results.2 A meta-analysis of randomized trials5 also suggested potential adverse effects on mortality with doses higher than 400 IU/d. While it is true that some previous trials (such as CHAOS and SPACE) showed a reduced risk of cardiovascular disease, these tended to be smaller and of shorter duration, as well as conducted in specialized populations.2 Larger trials, such as Heart Outcomes Prevention Evaluation (HOPE), Heart Protection Study (HPS), and Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarcto Miocardico (GISSI), demonstrated little effect on cardiovascular disease. While small trials assessing intermediate outcomes such as progression of atherosclerosis (including CLAS, the Harvard IVUS [intravascular ultrasonography] study, and ASAP) have suggested promising effects of antioxidants, such surrogate outcomes are not the same as clinical events. These data, though,

in conjunction with our observation that women randomly assigned to both vitamins C and E supplementation in our trial had a reduced risk of stroke, are interesting and warrant further investigation. In general, while questions remain, the totality of evidence available to date does not support widespread use of antioxidant vitamins in the prevention of cardiovascular disease. REFERENCES 1. Cook NR, Albert CM, Gaziano JM; et al. A randomized factorial trial of vitamins C and E and beta carotene in the secondary prevention of cardiovascular events in women. Arch Intern Med. 2007;167(15):1610-1618. FREE FULL TEXT 2. Bassuk SS, Manson JE, Gaziano JM. Antioxidant vitamins. In: Manson JE, Buring JE, Ridker PM, Gaziano JM, eds. Clinical Trials in Heart Disease. Philadelphia, PA: Elsevier; 2004:364-376. 3. Lee IM, Cook NR, Gaziano JM; et al. Vitamin E in the primary prevention of cardiovascular

disease and cancer: the Women's Health Study: a randomized controlled trial. JAMA. 2005;294(1):56-65. FREE FULL TEXT 4. Stampfer MJ, Hennekens CH, Manson JE; et al. Vitamin E consumption and the risk of coronary disease in women. N Engl J Med. 1993;328(20):1444-1449. FREE FULL TEXT 5. ER, Pastor-Barriuso R, Dalal D, Riemersma RA, Appel LJ, Guallar E. Meta-analysis: high dosage vitamin E supplementation may increase all-cause mortality. Ann Intern Med. 2005;142(1):37-46. FREE FULL TEXT -- Al Pater, alpater@...