Susanne Rautiainen

Total antioxidant capacity of diet and risk of stroke: a population-based prospective cohort of women.

Background and Purpose— Consumption of antioxidant-rich foods may reduce the risk of stroke by inhibition of oxidative stress and inflammation. Total antioxidant capacity (TAC) takes into account all antioxidants and the synergistic effects between them. We examined the association between dietary TAC and stroke incidence in cardiovascular disease (CVD)-free women and in women with CVD history at baseline. Methods— The study included women (31 035 CVD-free and 5680 with CVD history at baseline), aged 49 to 83 years, from the Swedish Mammography Cohort. Diet was assessed with a food frequency questionnaire. Dietary TAC was calculated using oxygen radical absorbance capacity values. Stroke cases were ascertained by linkage with the Swedish Hospital Discharge Registry. Results— During follow-up (September 1997 to December 2009), we identified 1322 stroke cases (988 cerebral infarctions, 226 hemorrhagic strokes, and 108 unspecified strokes) among CVD-free women and 1007 stroke cases (796 cerebral infarctions, 100 hemorrhagic strokes, and 111 unspecified strokes) among women with a CVD history. The multivariable hazard ratio of total stroke comparing the highest with the lowest quintile of dietary TAC was 0.83 (95% CI, 0.70–0.99; P for trend=0.04) in CVD-free women. Among women with a CVD history, the hazard ratios for the highest versus lowest quartile of TAC were 0.90 (95% CI, 0.75–1.07; P for trend=0.30) for total stroke and 0.55 (95% CI, 0.32–0.95; P for trend=0.03) for hemorrhagic stroke. Conclusions— These findings suggest that dietary TAC is inversely associated with total stroke among CVD-free women and hemorrhagic stroke among women with CVD history.

Total antioxidant capacity from diet and risk of myocardial infarction: a prospective cohort of women.

BACKGROUND There are no previous studies investigating the effect of all dietary antioxidants in relation to myocardial infarction. The total antioxidant capacity of diet takes into account all antioxidants and synergistic effects between them. The aim of this study was to examine how total antioxidant capacity of diet and antioxidant-containing foods were associated with incident myocardial infarction among middle-aged and elderly women. METHODS In the population-based prospective Swedish Mammography Cohort of 49-83-year-old women, 32,561 were cardiovascular disease-free at baseline. Women completed a food-frequency questionnaire, and dietary total antioxidant capacity was calculated using oxygen radical absorbance capacity values. Information on myocardial infarction was identified from the Swedish Hospital Discharge and the Cause of Death registries. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox proportional hazard models. RESULTS During the follow-up (September 1997-December 2007), we identified 1114 incident cases of myocardial infarction (321,434 person-years). In multivariable-adjusted analysis, the HR for women comparing the highest quintile of dietary total antioxidant capacity to the lowest was 0.80 (95% CI, 0.67-0.97; P for trend=0.02). Servings of fruit and vegetables and whole grains were nonsignificantly inversely associated with myocardial infarction. CONCLUSIONS These data suggest that dietary total antioxidant capacity, based on fruits, vegetables, coffee, and whole grains, is of importance in the prevention of myocardial infarction.

Vitamin C supplements and the risk of age-related cataract: a population-based prospective cohort study in women

BACKGROUND Experimental animal studies have shown adverse effects of high-dose vitamin C supplements on age-related cataract. OBJECTIVE We examined whether vitamin C supplements (approximately 1000 mg) and multivitamins containing vitamin C (approximately 60 mg) are associated with the incidence of age-related cataract extraction in a population-based, prospective cohort of women. DESIGN Our study included 24,593 women aged 49-83 y from the Swedish Mammography Cohort (follow-up from September 1997 to October 2005). We collected information on dietary supplement use and lifestyle factors with the use of a self-administrated questionnaire. Cataract extraction cases were identified by linkage to the cataract extraction registers in the geographical study area. RESULTS During the 8.2 y of follow-up (184,698 person-years), we identified 2497 cataract extraction cases. The multivariable hazard ratio (HR) for vitamin C supplement users compared with that for nonusers was 1.25 (95% CI: 1.05, 1.50). The HR for the duration of >10 y of use before baseline was 1.46 (95% CI: 0.93, 2.31). The HR for the use of multivitamins containing vitamin C was 1.09 (95% CI: 0.94, 1.25). Among women aged > or = 65 y, vitamin C supplement use increased the risk of cataract by 38% (95% CI: 12%, 69%). Vitamin C use among hormone replacement therapy users compared with that among nonusers of supplements or of hormone replacement therapy was associated with a 56% increased risk of cataract (95% CI: 20%, 102%). Vitamin C use among corticosteroid users compared with that among nonusers of supplements and corticosteroids was associated with an HR of 1.97 (95% CI: 1.35, 2.88). CONCLUSION Our results indicate that the use of vitamin C supplements may be associated with higher risk of age-related cataract among women.

Total Antioxidant Capacity of Diet and Risk of Heart Failure: A Population-based Prospective Cohort of Women

BACKGROUND Few studies have investigated the association between individual antioxidants and risk of heart failure. No previous study has investigated the role of all antioxidants present in diet in relation to heart failure. The aim of this study was to assess the association between total antioxidant capacity of diet, which reflects all of the antioxidant compounds in food and the interactions between them, and the incidence of heart failure among middle-aged and elderly women. METHODS In September 1997, 33,713 women (aged 49-83 years) from the Swedish Mammography Cohort completed a food-frequency questionnaire. Estimates of dietary total antioxidant capacity were based on the Oxygen Radical Absorbance Capacity assay measurements of foods. Women were followed for incident heart failure (hospitalization or mortality of heart failure as the primary cause) through December 2009 using administrative health registries. Cox proportional hazard models were used to calculate relative risks and 95% confidence intervals. RESULTS During 11.3 years of follow-up (394,059 person-years), we identified 894 incident cases of heart failure. Total antioxidant capacity of diet was inversely associated with heart failure (the multivariable-adjusted relative risk in the highest quintile compared with the lowest was 0.58 [95% confidence interval, 0.47-0.72; P for trend<.001]). The crude incidence rate was 18/10,000 person-years in the highest quintile versus 34/10,000 person-years in the lowest quintile. CONCLUSIONS The total antioxidant capacity of diet, an estimate reflecting all antioxidants in diet, was associated with lower risk of heart failure. These results indicate that a healthful diet high in antioxidants may help prevent heart failure.

Multivitamin use and the risk of myocardial infarction: a population-based cohort of Swedish women

BACKGROUND Dietary supplements are widely used in industrialized countries. OBJECTIVE The objective was to examine the association between multivitamin use and myocardial infarction (MI) in a prospective, population-based cohort of women. DESIGN The study included 31,671 women with no history of cardiovascular disease (CVD) and 2262 women with a history of CVD aged 49-83 y from Sweden. Women completed a self-administered questionnaire in 1997 regarding dietary supplement use, diet, and lifestyle factors. Multivitamins were estimated to contain nutrients close to recommended daily allowances: vitamin A (0.9 mg), vitamin C (60 mg), vitamin D (5 μg), vitamin E (9 mg), thiamine (1.2 mg), riboflavin (1.4 mg), vitamin B-6 (1.8 mg), vitamin B-12 (3 μg), and folic acid (400 μg). RESULTS During an average of 10.2 y of follow-up, 932 MI cases were identified in the CVD-free group and 269 cases in the CVD group. In the CVD-free group, use of multivitamins only, compared with no use of supplements, was associated with a multivariable-adjusted hazard ratio (HR) of 0.73 (95% CI: 0.57, 0.93). The HR for multivitamin use together with other supplements was 0.70 (95% CI: 0.57, 0.87). The HR for use of supplements other than multivitamins was 0.93 (95% CI: 0.81, 1.08). The use of multivitamins for ≥5 y was associated with an HR of 0.59 (95% CI: 0.44, 0.80). In the CVD group, use of multivitamins alone or together with other supplements was not associated with MI. CONCLUSIONS The use of multivitamins was inversely associated with MI, especially long-term use among women with no CVD. Further prospective studies with detailed information on the content of preparations and the duration of use are needed to confirm or refute our findings.

High-Dose Supplements of Vitamins C and E, Low-Dose Multivitamins, and the Risk of Age-related Cataract: A Population-based Prospective Cohort Study of Men

We examined the associations of high-dose supplements of vitamins C and E and low-dose multivitamins with the risk of age-related cataract among 31,120 Swedish men, aged 45-79 years, in a population-based prospective cohort. Dietary supplement use was assessed from a questionnaire at baseline in 1998. During follow-up (January 1998-December 2006), 2,963 incident age-related cataract cases were identified. The multivariable-adjusted hazard ratio for men using vitamin C supplements only was 1.21 (95% confidence interval (CI): 1.04, 1.41) in a comparison with that of non-supplement users. The hazard ratio for long-term vitamin C users (≥10 years before baseline) was 1.36 (95% CI: 1.02, 1.81). The risk of cataract with vitamin C use was stronger among older men (>65 years) (hazard ratio = 1.92, 95% CI: 1.41, 2.60) and corticosteroid users (hazard ratio = 2.11, 95% CI: 1.48, 3.02). The hazard ratio for vitamin E use only was 1.59 (95% CI: 1.12, 2.26). Use of multivitamins only or multiple supplements in addition to vitamin C or E was not associated with cataract risk. These results suggest that the use of high-dose (but not low-dose) single vitamin C or E supplements may increase the risk of age-related cataract. The risk may be even higher among older men, corticosteroid users, and long-term users.

Dietary supplements and disease prevention — a global overview

Dietary supplements are widely used and offer the potential to improve health if appropriately targeted to those in need. Inadequate nutrition and micronutrient deficiencies are prevalent conditions that adversely affect global health. Although improvements in diet quality are essential to address these issues, dietary supplements and/or food fortification could help meet requirements for individuals at risk of deficiencies. For example, supplementation with vitamin A and iron in developing countries, where women of reproductive age, infants and children often have deficiencies; with folic acid among women of reproductive age and during pregnancy; with vitamin D among infants and children; and with calcium and vitamin D to ensure bone health among adults aged ≥65 years. Intense debate surrounds the benefits of individual high-dose micronutrient supplementation among well-nourished individuals because the alleged beneficial effects on chronic diseases are not consistently supported. Daily low-dose multivitamin supplementation has been linked to reductions in the incidence of cancer and cataracts, especially among men. Baseline nutrition is an important consideration in supplementation that is likely to modify its effects. Here, we provide a detailed summary of dietary supplements and health outcomes in both developing and developed countries to help guide decisions about dietary supplement recommendations.

Confirmed hypertension and plasma 25(OH)D concentrations amongst elderly men

Abstract.  Burgaz A, Byberg L, Rautiainen S, Orsini N, Håkansson N, Ärnlöv J, Sundström J, Lind L, Melhus H, Michaëlsson K, Wolk A (Institute of Environmental Medicine, Karolinska Institiute, Stockholm; Department of Surgical Sciences, Section of Orthopaedics; Department of Public Health and Caring Sciences/Geriatrics, Uppsala University, Uppsala; School of Health and Social Studies, Dalarna University, Falun; and Department of Medical Sciences, Uppsala University Hospital, Uppsala, Sweden). Confirmed hypertension and plasma 25(OH)D concentrations among elderly men. J Intern Med 2011; 269: 211–218.

Total antioxidant capacity of the diet and risk of age-related cataract: a population-based prospective cohort of women.

IMPORTANCE To our knowledge, no previous epidemiologic study has investigated the association between all antioxidants in the diet and age-related cataract. The total antioxidant capacity (TAC) concept aims to measure the capacity from all antioxidants in the diet by also taking synergistic effects into account. OBJECTIVE To investigate the association between the TAC of the diet and the incidence of age-related cataract in a population-based prospective cohort of middle-aged and elderly women. DESIGN, SETTING, AND PARTICIPANTS Questionnaire-based nutrition survey within the prospective Swedish Mammography Cohort study, which included 30,607 women (aged 49-83 years) who were observed for age-related cataract incidence for a mean of 7.7 years. EXPOSURE The TAC of the diet was estimated using a database of foods analyzed with the oxygen radical absorbance capacity assay. MAIN OUTCOMES AND MEASURES Information on incident age-related cataract diagnosis and extraction was collected through linkage to registers in the study area. RESULTS There were 4309 incident cases of age-related cataracts during the mean 7.7 years of follow-up (234,371 person-years). The multivariable rate ratio in the highest quintile of the TAC of the diet compared with the lowest was 0.87 (95% CI, 0.79-0.96; P for trend = .03). The main contributors to dietary TAC in the study population were fruit and vegetables (44.3%), whole grains (17.0%), and coffee (15.1%). CONCLUSIONS AND RELEVANCE Dietary TAC was inversely associated with the risk of age-related cataract. Future studies examining all antioxidants in the diet in relation to age-related cataract are needed to confirm or refute our findings.

The Role of Calcium in the Prevention of Cardiovascular Disease—A Review of Observational Studies and Randomized Clinical Trials

Calcium is a mineral that is important for bone health and has also been suggested to play a role in the prevention of cardiovascular disease (CVD). Lately, the potential effects of both inadequate and excessive calcium intake have received growing attention. In this review, we summarize the evidence from experimental, epidemiologic, and clinical studies investigating the role of calcium intake, either from the diet or from supplements, as well as blood concentrations, in relation to the risk of CVD in adults. In vitro and in vivo laboratory studies suggest that calcium may be involved in CVD development through multiple pathways, including blood cholesterol, insulin secretion and sensitivity, vasodilation, inflammatory profile, thrombosis, obesity, and vascular calcification. Several prospective epidemiologic studies have examined how dietary or supplemental calcium intake is associated with CVD incidence or mortality in middle-aged and older adults, and the results are inconsistent. Prospective studies investigating blood concentrations of calcium have also reported mixed results. However, changes in blood calcium concentrations may reflect a disturbed calcium phosphate balance, which is associated with increased risk of CVD. To date there is no randomized clinical trial that has been designed specifically to test the effect of calcium supplementation on the risk of CVD as the primary end point. Existing trials have performed secondary analyses, and most of them have been conducted among postmenopausal women. These trials suggest that calcium supplementation has no effect on CVD development; however, they do not allow a definitive conclusion to be drawn. The average daily intake of calcium is low in many populations; however, the evidence for a potential role of dietary or supplemental calcium in the prevention of CVD remains insufficient and inconclusive. Only large-scale randomized trials designed to investigate the effects of calcium supplementation on CVD events as the primary end point, as well as short-term trials investigating the effect on coronary biomarkers, can provide a definitive answer.