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Community-wide programs to collect blood for a research serum bank were carried out in Washington County, Maryland in 1974 and 1989. Of the 8395 persons who participated in both programs, 64 were controls in a nested case-control study of the association of antioxidant micronutrients with subsequent breast cancer, and 30 and 166 were controls in similar studies of lung and prostate cancer. Assay results for five carotenoids, two retinoids, and two tocopherols in samples of blood collected 15 years apart were thus available for comparisons of micronutrient concentrations. The mean Spearman rank order correlation coefficient for all comparisons was 0.44, with two coefficients greater than 0.60 and two less than 0.30. Blood pressure readings at the two blood collections had a mean rank order correlation coefficient of 0.46. Because blood pressure readings in 1974 were shown to be significantly predictive of atherosclerosis 15-18 years later, the present results suggest that ranked concentrations of antioxidant micronutrients from a single sample are sufficiently representative to be used as predictors of subsequent concentrations and are thus suitable for assessment as risk factors for subsequent illnesses.

Background: Selenium and alpha-tocopherol, the major form of vitamin E in supplements, appear to have a protective effect against prostate cancer. However, little attention has been paid to the possible role of gamma-tocopherol, a major component of vitamin E in the U.S. diet and the second most common tocopherol in human serum. A nested case-control study was conducted to examine the associations of alpha-tocopherol, gamma-tocopherol, and selenium with incident prostate cancer., Methods: In 1989, a total of 10,456 male residents of Washington County, MD, donated blood for a specimen bank. A total of 117 of 145 men who developed prostate cancer and 233 matched control subjects had toenail and plasma samples available for assays of selenium, alpha-tocopherol, and gamma-tocopherol. The association between the micronutrient concentrations and the development of prostate cancer was assessed by conditional logistic regression analysis. All statistical tests were two-sided., Results: The risk of prostate cancer declined, but not linearly, with increasing concentrations of alpha-tocopherol (odds ratio (highest versus lowest fifth) = 0.65; 95% confidence interval = 0.32--1.32; P(trend) =.28). For gamma-tocopherol, men in the highest fifth of the distribution had a fivefold reduction in the risk of developing prostate cancer than men in the lowest fifth (P:(trend) =.002). The association between selenium and prostate cancer risk was in the protective direction with individuals in the top four fifths of the distribution having a reduced risk of prostate cancer compared with individuals in the bottom fifth (P(trend) =.27). Statistically significant protective associations for high levels of selenium and alpha-tocopherol were observed only when gamma-tocopherol concentrations were high., Conclusions: The use of combined alpha- and gamma- tocopherol supplements should be considered in upcoming prostate cancer prevention trials, given the observed interaction between alpha-tocopherol, gamma-tocopherol, and selenium.

Background: The associations observed between passive smoking and adverse health outcomes have generated controversy. In part, this could be because the diets of passive smokers, like those of active smokers, differ from those of persons who are not exposed to cigarette smoke, especially with regard to antioxidants., Objective: Our objective was to assess the relation between household exposure to passive smoking and serum concentrations of retinol, tocopherols, and carotenoids., Design: A cross-sectional study was conducted in Washington County, MD, to compare exposure to passive smoking at home, recorded in a private census of county residents in 1975, with micronutrient concentrations assayed in serum collected in 1974. This comparison was possible for 1590 control subjects in nested case-control studies conducted between 1986 and 1998., Results: Among persons who were not current smokers, those who lived with smokers tended to have lower serum total carotenoid, alpha-carotene, ss-carotene, and cryptoxanthin concentrations than did those who lived in households with no smokers. There was little evidence that exposure to passive smoking was associated with reduced serum concentrations of lutein and zeaxanthin, lycopene, retinol, alpha-tocopherol, or gamma-tocopherol., Conclusions: Among nonsmokers, exposure to passive smoking tended to be associated with lower serum concentrations of the carotenoids most strongly associated with active smoking (total carotenoids, alpha-carotene, ss-carotene, and cryptoxanthin). The associations were weaker for passive smoking than for active smoking. The consistency of the associations observed for active and passive smoking indicates that exposure to passive smoking may result in decreased circulating concentrations of selected micronutrients.

Oxidative DNA damage may be important in mutagenic, carcinogenic, and aging processes. Although it is plausible that antioxidant vitamins may reduce oxidative DNA damage, evidence from human studies has been sparse and inconsistent. We determined the short-term effects of vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) supplements on oxidative DNA damage in a double-masked, placebo-controlled, 2x2 factorial trial in 184 nonsmoking adults. Mean duration of supplementation was 2 months. Oxidative DNA damage was measured by 24-h urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG). At baseline, urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was associated with race (15.6 +/- 0.8 in African Americans versus 20.3 +/- 1.2 in Caucasians, P = 0.001), prior antioxidant supplement use (18.6 +/- 0.8 in users versus 13.8 +/- 1.5 in non-users, P = 0.007), and regular exercise (19.2 +/- 1.1 in exercisers versus 16.6 +/- 0.9 in non-exercisers, P = 0.04). Fruit and vegetable intake and serum ascorbic acid were inversely associated with urinary 8-OHdG (P-trend = 0.02 and 0.016, respectively). The benefits of fruit and vegetable intake became evident with the consumption being at least three servings/day. At the end of supplementation, change from baseline in urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was -0.6 +/- 1.4 (P = 0.61), 0.6 +/- 1.1 (P = 0.59), 0.5 +/- 1.0 (P = 0.61), and 1.6 +/- 1.4 (P = 0.27) in the placebo, vitamin C alone, vitamin E alone, and combined vitamins C and E groups, respectively. In overall and subgroup analyses, there was no significant main effect or interaction effect of the supplements on urinary 8-OHdG. In conclusion, supplementation of diet with vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) had no significant main effect or interaction effect on oxidative DNA damage as measured by urinary 8-OHdG in nonsmoking adults. However, several aspects of a healthy lifestyle were associated with lower oxidative DNA damage.

Lung cancer cases diagnosed during the period 1975 through 1993 and matched controls were identified in the rosters of Washington County, Maryland residents who had donated blood for a serum bank in 1974 or 1989. Plasma from participants in the 1989 project was assayed for ascorbic acid; serum or plasma was assayed for participants in either project for alpha- and beta-carotene, cryptoxanthin, lutein/zeaxanthin, lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity. Among the total group of 258 cases and 515 controls, serum/plasma concentrations were significantly lower among cases than controls for cryptoxanthin, beta-carotene, and lutein/zeaxanthin with case-control differences of -25.5, -17.1, and -10.1%, respectively. Modest nonsignificant case-control differences in a protective direction were noted for alpha-carotene and ascorbic acid. There were only trivial differences for lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity. Findings are reported for males and females and for persons who had never smoked cigarettes, former smokers, and current smokers at baseline. These results and those from previous studies suggest that beta-carotene is a marker for some protective factor(s) against lung cancer; that cryptoxanthin, alpha-carotene, and ascorbic acid need to be investigated further as potentially protective factors or associates of a protective factor; and that lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity are unlikely to be associated with lung cancer risk. Until specific preventive factors are identified, the best protection against lung cancer is still the avoidance of airborne carcinogens, especially tobacco smoke; second best is the consumption of a diet rich in fruits and vegetables.

Aliquots from 40 plasma pools preserved with metaphosphoric acid were assayed for their ascorbic acid values after 12, 24, and 42 months of storage at -70 degrees C. Similarly, aliquots from 16 plasma pools were assayed for values of retinol, several carotenoids, and two tocopherols at 15.5, 27.5, and 51.5 months of storage at -70 degrees C. There were no indications of important losses of these antioxidant micronutrients during storage from the first to the last assay.

A literature review of the effects of long-term freezer storage on concentrations of antioxidant micronutrients in serum or plasma showed that a high proportion of the studies that compared the concentrations of retinol, beta-carotene, or alpha-tocopherol in fresh and stored serum were deficient because of small numbers of observations, imprecise descriptions of procedures, and short periods of storage. Data from nested case-control studies of the associations of these micronutrients with cancer are confounded by differences in the study populations. Nevertheless, the overall impression is strong that retinol is stable at storage temperatures as warm as -20 degrees C for at least 15 years, that moderate losses of alpha-tocopherol occur at temperatures above -40 degrees C during that period, and that only a small proportion of beta-carotene persists at storage temperatures above -40 degrees C. At -70 degrees C or colder, all three micronutrients appear to be stable for at least 15 years.

In 1974 and 1975, serum specimens were collected from 25,802 volunteers in Washington County, Maryland. The serum was kept frozen at -73 degrees C until the time of assay. Prediagnostic samples from 436 cancer cases and 765 matched control subjects have been assayed. Nine sites have been studied: colon, rectum, pancreas, lung, melanoma, basal cell of skin, breast, prostate, and bladder. Serum beta-carotene levels showed a strong protective association with lung cancer, suggestive protective associations with melanoma and bladder cancer, and a suggestive but nonprotective association with rectal cancer. Serum vitamin E levels had a protective association with lung cancer; none of the other sites showed impressive associations. Low levels of serum lycopene were strongly associated with pancreatic cancer and less strongly associated with cancer of the bladder and rectum.

To examine the association between serum nutrients and the development of bladder cancer we measured selenium, alpha-tocopherol, lycopene, beta-carotene, retinol, and retinol-binding protein in serum collected from 25,802 persons in Washington County, MD, in 1974. Serum samples were kept frozen at -70 degrees C. In the subsequent 12-year period, 35 cases of bladder cancer developed among participants. Comparisons of serum levels in 1974 among cases and two matched controls for each case showed that selenium was significantly lower among cases than controls (P = 0.03), lycopene was lower among cases at a borderline level of significance (P = 0.07), and alpha-tocopherol was nonsignificantly lower (P = 0.13). For selenium there was a nearly linear increase in risk with decreasing serum levels (P = 0.03). When examined by tertiles, the odds ratio associated with the lowest tertile of selenium compared to the highest tertile was 2.06. Serum levels of retinol, retinol-binding protein, and beta-carotene were similar among cases and controls. These results support a role for selenium in the prevention of bladder cancer.

Background: Selenium and alpha-tocopherol, the major form of vitamin E in supplements, appear to have a protective effect against prostate cancer. However, little attention has been paid to the possible role of gamma-tocopherol, a major component of vitamin E in the U.S. diet and the second most common tocopherol in human serum. A nested case-control study was conducted to examine the associations of alpha-tocopherol, gamma-tocopherol, and selenium with incident prostate cancer.Methods: In 1989, a total of 10,456 male residents of Washington County, MD, donated blood for a specimen bank. A total of 117 of 145 men who developed prostate cancer and 233 matched control subjects had toenail and plasma samples available for assays of selenium, alpha-tocopherol, and gamma-tocopherol. The association between the micronutrient concentrations and the development of prostate cancer was assessed by conditional logistic regression analysis. All statistical tests were two-sided.Results: The risk of prostate cancer declined, but not linearly, with increasing concentrations of alpha-tocopherol (odds ratio (highest versus lowest fifth) = 0.65; 95% confidence interval = 0.32--1.32; P(trend) =.28). For gamma-tocopherol, men in the highest fifth of the distribution had a fivefold reduction in the risk of developing prostate cancer than men in the lowest fifth (P:(trend) =.002). The association between selenium and prostate cancer risk was in the protective direction with individuals in the top four fifths of the distribution having a reduced risk of prostate cancer compared with individuals in the bottom fifth (P(trend) =.27). Statistically significant protective associations for high levels of selenium and alpha-tocopherol were observed only when gamma-tocopherol concentrations were high.Conclusions: The use of combined alpha- and gamma- tocopherol supplements should be considered in upcoming prostate cancer prevention trials, given the observed interaction between alpha-tocopherol, gamma-tocopherol, and selenium. [ABSTRACT FROM AUTHOR]

Objectives: Because oxidative damage has been implicated in the pathogenesis of rheumatoid arthritis and systemic lupus erythematosus, this study was designed to see if serum concentrations of alpha tocopherol, beta carotene, and retinol, substances believed to be involved in the prevention or repair of oxidative damage, might be lower among persons who develop rheumatoid arthritis or systemic lupus erythematosus than among those who do not.Methods: For this prospective case-control study, persons with rheumatoid arthritis and systemic lupus erythematosus that developed two to 15 years after donating blood for a serum bank in 1974 were designated as cases. For each case, four controls were selected from the serum bank donors, matched for race, sex, and age. Stored serum samples from cases and controls were assayed for alpha tocopherol, beta carotene, and retinol.Results: Cases of both diseases had lower serum concentrations of alpha tocopherol, beta carotene, and retinol in 1974 than their matched controls. For rheumatoid arthritis, the difference for beta carotene (-29%) was statistically significant.Conclusions: These findings support those of a previous study that low antioxidant status is a risk factor for rheumatoid arthritis. They suggest a similar association for systemic lupus erythematosus. [ABSTRACT FROM AUTHOR]