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David R Jacobs

Publications and source records attributed to David R Jacobs.

At least 37 records · Page 2Linked to original sources

Comparison of the serum ferritin and percentage of transferrin saturation as exposure markers of iron-driven oxidative stress-related disease outcomes.

BACKGROUND: Iron-catalyzed oxidative stress may be the primary mechanism for the pathogenesis of diseases related to iron excess. We hypothesized previously that certain markers of iron in bound form that are commonly used in epidemiologic studies might be inappropriate for investigating iron-related adverse health effects because oxidative stress requires iron in redox-active form. METHODS: To study aspects of this hypothesis, we examined the association between levels of serum ferritin or the percentage of transferrin saturation (%TS) and levels of serum antioxidant vitamins and C-reactive protein (CRP). This cross-sectional analysis included 11245 adults aged 20 years or older who participated in the Third National Health and Nutrition Examination Survey. RESULTS: Adjusted concentrations of serum alpha-carotene, beta-carotene, beta-cryptoxanthin, and lycopene were inversely correlated with the serum ferritin concentration (P for trend < .01), even within the lower deciles of the serum ferritin. In contrast, the %TS was significantly and positively associated with beta-cryptoxanthin, vitamin C, and vitamin E. In addition, the serum ferritin was positively associated but the %TS was strongly and inversely associated with the serum CRP (P for trend < .01). CONCLUSIONS: The serum ferritin and %TS showed contrasting associations with serum antioxidant vitamin levels and CRP although they have been used interchangeably in epidemiologic studies as markers of body iron. These results suggest that the %TS may not be a valid marker of exposure to iron-related oxidative stress. It appears that the serum ferritin is the preferred marker for assessment of clinical outcomes presumed to be caused by iron-related oxidative stress.

Adult↗

Trends in blood pressure, hypertension control, and stroke mortality: the Minnesota Heart Survey.

OBJECTIVE: The study's objective was to determine population trends in blood pressure, hypertension prevalence, hypertension control, and stroke mortality. METHODS: We performed population-based surveys of 2906 to 5630 adults from 1980 to 1982, 1985 to 1987, 1990 to 1992, 1995 to 1997, and 2000 to 2002, and stroke mortality from 1980 to 2002, in the Minneapolis/St Paul, Minn metropolitan area (2.63 million population according to the 2000 census). Randomly selected resident adults aged 25 to 74 years (n = 21773) were each screened once. The main outcome measures were standardized measures of blood pressure, treatment and control of hypertension, and stroke mortality rates. RESULTS: The mean systolic blood pressure adjusted for age decreased in men (-1.5 mm Hg [95% confidence interval -0.3 to -2.7], P <.01) and women (-1.8 mm Hg [95% confidence interval -0.5 to -3.0], P <.001) from 1980 to 1982 and 2000 to 2002. The mean diastolic blood pressure was unchanged for men (0 mm Hg) and women (-0.4 mm Hg, not significant). The proportion of the population taking antihypertensive medications decreased in the 1990s but returned to 1980s levels from 2000 to 2002. The use of other methods to decrease blood pressure (diet, exercise, and weight loss) peaked in the 1990 to 1992 survey and then decreased. Proportions of hypertensive patients in the aware, treated, and/or controlled categories leveled in the 1980s and 1990s, but improved substantially from 1995 to 1997 and 2000 to 2002 with blood pressure controlled at the less than 140 and/or 90 mm Hg criteria in 44% of the men and 55% of the women. Population mortality trends for stroke paralleled those for hypertension control. CONCLUSIONS: Population data beginning in 1980 to 1982 from the Minnesota Heart Survey indicate a leveling in the detection and control of hypertension in the 1990s followed by improvement from 2000 to 2002.

Adult↗

Reliability and validity of a brief questionnaire to assess calcium intake of middle-school-aged children.

OBJECTIVE: Evaluate the validity and reliability of a short (10-item) calcium food frequency questionnaire (FFQ) for use with middle-school-aged (11 to 14 years of age) children. DESIGN: The calcium FFQ was completed twice, with 1 week between administrations. Three 24-hour dietary recalls were collected from each participant after the second administration of the calcium FFQ. SUBJECTS/SETTING: Students in an ethnically diverse middle school in Minneapolis, MN (n=248). MAIN OUTCOME MEASURES: Calcium intake estimates from the calcium FFQ and dietary recalls. STATISTICAL ANALYSES: Correlations between calcium intake estimates from the first and second questionnaire administrations of the calcium FFQ were calculated and paired t tests were conducted to compare mean calcium intake estimates from each questionnaire administration. Mean intake estimates from the calcium FFQ and the dietary recalls were compared. Also, correlations between intake estimates from the calcium FFQ and the recalls were calculated. RESULTS: Correlation between calcium intake estimates derived from the first and second administration of the calcium FFQ was 0.74. Mean calcium intake estimates from the calcium FFQ and the average of the three dietary recalls were 856 mg/day and 993 mg/day, respectively (P<0.001). The correlation between calcium intake estimates derived from the calcium FFQ and the average of the recalls was 0.43. CONCLUSIONS: Reliability of the FFQ was found to be good while validity was weaker, with calcium intake from the calcium FFQ moderately associated with estimates from dietary recalls. Where a brief instrument for assessing calcium intake of middle-school-aged children is needed, the calcium FFQ evaluated in this study may be useful.

Adolescent↗

Prevalence of age-related macular degeneration in 4 racial/ethnic groups in the multi-ethnic study of atherosclerosis.

OBJECTIVE: To describe the prevalence of age-related macular degeneration (AMD) in 4 racial/ethnic groups (white, black, Hispanic, and Chinese) that participated in the second examination of the Multi-ethnic Study of Atherosclerosis (MESA). DESIGN: Prospective cohort study. PARTICIPANTS: Six thousand one hundred seventy-six 45- to 85-year-old subjects selected from 6 United States communities. METHODS: Fundus images were taken using a 45 degrees digital camera through dark-adapted pupils and were graded for drusen size, type, area, increased retinal pigment, retinal pigment epithelial depigmentation, neovascular lesions, and geographic atrophy using the modified Wisconsin Age-Related Maculopathy Grading System. MAIN OUTCOME MEASURE: Age-related macular degeneration. RESULTS: Prevalences of AMD were 2.4% (black), 4.2% (Hispanic), 4.6% (Chinese), to 5.4% (white) (P<0.001 for any differences among groups). The highest prevalence of any AMD occurred in those 75 to 84 years old, varying from 7.4% in blacks to 15.8% in whites and Chinese (P = 0.03). Estimated prevalences of late AMD were 0.3% (black), 0.2% (Hispanic), 0.6% (white), and 1.0% (Chinese). These differences were marginally significant (age and gender adjusted, P = 0.08). The frequency of exudative AMD was highest in Chinese (age- and gender-adjusted odds ratio, 4.30; 95% confidence interval, 1.30-14.27) compared with whites. Differences in age, gender, pupil size, body mass index, smoking, alcohol drinking history, diabetes, and hypertension status did not explain the variability among the 4 racial/ethnic groups. CONCLUSIONS: Low prevalences of AMD were found in the MESA cohort in all groups. A lower prevalence of AMD was found in blacks compared with whites. The higher prevalence of exudative AMD in Chinese needs further study.

Age Distribution↗

Health benefits of nuts: potential role of antioxidants.

A diet rich in fruits, vegetables and minimally refined cereals is associated with lower risk for chronic degenerative diseases. Since oxidative stress is common in chronic degenerative disease, it has been assumed that dietary antioxidants may explain this protective effect. Every dietary plant contains numerous types of antioxidants with different properties. Many of these antioxidants cooperate in oxidative stress reduction in plants, and we hypothesize that many different antioxidants may also be needed for the proper protection of animal cells. To test this hypothesis, it is useful to identify dietary plants with high total antioxidant content. Several nuts are among the dietary plants with the highest content of total antioxidants. Of the tree nuts, walnuts, pecans and chestnuts have the highest contents of antioxidants. Walnuts contain more than 20 mmol antioxidants per 100 g, mostly in the walnut pellicles. Peanuts (a legume) also contribute significantly to dietary intake of antioxidants. These data are in accordance with our present extended analysis of an earlier report on nut intake and death attributed to various diseases in the Iowa Women's Health Study. We observed that the hazard ratio for total death rates showed a U-shaped association with nut/peanut butter consumption. Hazard ratio was 0.89 (CI = 0.81-0.97) and 0.81 (CI = 0.75-0.88) for nut/peanut butter intake once per week and 1-4 times per week, respectively. Death attributed to cardiovascular and coronary heart diseases showed strong and consistent reductions with increasing nut/peanut butter consumption. Further studies are needed to clarify whether antioxidants contribute to this apparent beneficial health effect of nuts.

Aged↗

Adiponectin, visceral fat, oxidative stress, and early macrovascular disease: the Coronary Artery Risk Development in Young Adults Study.

OBJECTIVE: Adiponectin is a collagen-like product of visceral fat that offers apparent protection against macrovascular disease. We evaluated the relationships of concentrations of adiponectin with oxidative stress and the major risk factors for and/or the presence of macrovascular disease. RESEARCH METHODS AND PROCEDURES: Adiponectin was measured by radioimmunoassay in serum from 3045 fasting participants (ages 33 to 45) of the Coronary Artery Risk Development in Young Adults Study. Cross-sectional correlation of the concentrations of adiponectin with F2-isoprostane concentrations (a marker of systemic oxidative damage), coronary artery calcification (CAC; an estimate of early macrovascular disease), and several macrovascular risk factors was analyzed. RESULTS: F2-isoprostanes and CAC were unrelated to adiponectin after minimal adjustment for gender, race, and center. After additional adjustment for insulin resistance and waist circumference and other macrovascular risk factors, adiponectin correlated positively with high-density lipoprotein-cholesterol (p < 0.0001), F2-isoprostanes (p < 0.0001), and CAC (less strongly, p < 0.01) and negatively with triglycerides (p < 0.0001) and C-reactive protein (marking inflammation, p = 0.01). DISCUSSION: Although these data are consistent with reduced cardiovascular disease risk imparted by adiponectin, the higher circulating levels of adiponectin present with oxidative stress and CAC (adjusting for waist and insulin resistance) may indicate an enhanced adiponectin secretory response of adipose tissue to the metabolic environment present in the early development of macrovascular disease. Thus, the elevated levels of adiponectin may comprise an attempt to alleviate risk for additional development and progression of macrovascular disease in an at-risk environment.

Adiponectin↗

Longitudinal associations between body mass index and serum carotenoids: the CARDIA study.

Cross-sectional studies report an inverse association between BMI and serum carotenoid concentration. The present study examined the prospective association between BMI and the serum concentration of five carotenoids in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Serum carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene), BMI, dietary intake, physical activity and dietary supplement use were measured at years 0 and 7 in 3071 black and white male and female participants, who were either persistent smokers or non-smokers. Among non-smokers, year 0 BMI predicted year 7 serum carotenoid levels: obese subjects (BMI > or =30 kg/m2) had an average concentration of the sum of four carotenoids (alpha-carotene +beta-carotene + zeaxanthin/lutein+beta-cryptoxanthin) that was 22 % lower than the concentration among subjects with a BMI of less than 22 kg/m2. In contrast, the sum of carotenoids among smokers was only 6 % lower. Relationships between BMI and serum lycopene were weak. The change from year 0 to year 7 in serum carotenoids, except for lycopene, was inversely associated with the change in BMI among non-smokers but not among smokers. Parallel findings were observed for BMI and serum gamma-glutamyl transferase level. In summary, the observation that BMI predicted the evolution of serum carotenoids during a 7-year follow-up among young non-smoking adults is consistent with the hypothesis that carotenoids are decreased in protecting against oxidative stress generated by adipose tissue, while smokers maintain a minimal level of serum carotenoids independent of adiposity. The results for lycopene were, however, discordant from those of the other carotenoids.

Adult↗

Consumption of coffee is associated with reduced risk of death attributed to inflammatory and cardiovascular diseases in the Iowa Women's Health Study.

BACKGROUND: Coffee is the major source of dietary antioxidants. The association between coffee consumption and risk of death from diseases associated with inflammatory or oxidative stress has not been studied. OBJECTIVE: We studied the relation of coffee drinking with total mortality and mortality attributed to cardiovascular disease, cancer, and other diseases with a major inflammatory component. DESIGN: A total of 41,836 postmenopausal women aged 55-69 y at baseline were followed for 15 y. After exclusions for cardiovascular disease, cancer, diabetes, colitis, and liver cirrhosis at baseline, 27,312 participants remained, resulting in 410,235 person-years of follow-up and 4265 deaths. The major outcome measure was disease-specific mortality. RESULTS: In the fully adjusted model, similar to the relation of coffee intake to total mortality, the hazard ratio of death attributed to cardiovascular disease was 0.76 (95% CI: 0.64, 0.91) for consumption of 1-3 cups/d, 0.81 (95% CI: 0.66, 0.99) for 4-5 cups/d, and 0.87 (95% CI: 0.69, 1.09) for > or =6 cups/d. The hazard ratio for death from other inflammatory diseases was 0.72 (95% CI: 0.55, 0.93) for consumption of 1-3 cups/d, 0.67 (95% CI: 0.50, 0.90) for 4-5 cups/d, and 0.68 (95% CI: 0.49, 0.94) for > or =6 cups/d. CONCLUSIONS: Consumption of coffee, a major source of dietary antioxidants, may inhibit inflammation and thereby reduce the risk of cardiovascular and other inflammatory diseases in postmenopausal women.

Aged↗

Dietary patterns are associated with biochemical markers of inflammation and endothelial activation in the Multi-Ethnic Study of Atherosclerosis (MESA).

BACKGROUND: Dietary patterns may influence cardiovascular disease risk through effects on inflammation and endothelial activation. OBJECTIVE: We examined relations between dietary patterns and markers of inflammation and endothelial activation. DESIGN: At baseline, diet (food-frequency questionnaire) and concentrations of C-reactive protein (CRP), interleukin 6 (IL-6), homocysteine, soluble intercellular adhesion molecule-1 (sICAM-1), and soluble E selectin were assessed in 5089 nondiabetic participants in the Multi-Ethnic Study of Atherosclerosis. RESULTS: Four dietary patterns were derived by using factor analysis. The fats and processed meats pattern (fats, oils, processed meats, fried potatoes, salty snacks, and desserts) was positively associated with CRP (P for trend < 0.001), IL-6 (P for trend < 0.001), and homocysteine (P for trend = 0.002). The beans, tomatoes, and refined grains pattern (beans, tomatoes, refined grains, and high-fat dairy products) was positively related to sICAM-1 (P for trend = 0.007). In contrast, the whole grains and fruit pattern (whole grains, fruit, nuts, and green leafy vegetables) was inversely associated with CRP, IL-6, homocysteine (P for trend < or = 0.001), and sICAM-1 (P for trend = 0.034), and the vegetables and fish pattern (fish and dark-yellow, cruciferous, and other vegetables) was inversely related to IL-6 (P for trend = 0.009). CRP, IL-6, and homocysteine relations across the fats and processed meats and whole grains and fruit patterns were independent of demographics and lifestyle factors and were not modified by race-ethnicity. CRP and homocysteine relations were independent of waist circumference. CONCLUSIONS: These results corroborate previous findings that empirically derived dietary patterns are associated with inflammation and show that these relations in an ethnically diverse population with unique dietary habits are similar to findings in more homogeneous populations.

Aged↗

Content of redox-active compounds (ie, antioxidants) in foods consumed in the United States.

BACKGROUND: Supplements containing ascorbic acid, alpha-tocopherol, or beta-carotene do not protect against oxidative stress-related diseases in most randomized intervention trials. We suggest that other redox-active phytochemicals may be more effective and that a combination of different redox-active compounds (ie, antioxidants or reductants) may be needed for proper protection against oxidative damage. OBJECTIVE: We aimed to generate a ranked food table with values for total content of redox-active compounds to test this alternative antioxidant hypothesis. DESIGN: An assay that measures the total concentration of redox-active compounds above a certain cutoff reduction potential was used to analyze 1113 food samples obtained from the US Department of Agriculture National Food and Nutrient Analysis Program. RESULTS: Large variations in the content of antioxidants were observed in different foods and food categories. The food groups spices and herbs, nuts and seeds, berries, and fruit and vegetables all contained foods with very high antioxidant contents. Most food categories also contained products almost devoid of antioxidants. Of the 50 food products highest in antioxidant concentrations, 13 were spices, 8 were in the fruit and vegetables category, 5 were berries, 5 were chocolate-based, 5 were breakfast cereals, and 4 were nuts or seeds. On the basis of typical serving sizes, blackberries, walnuts, strawberries, artichokes, cranberries, brewed coffee, raspberries, pecans, blueberries, ground cloves, grape juice, and unsweetened baking chocolate were at the top of the ranked list. CONCLUSION: This ranked antioxidant food table provides a useful tool for investigations into the possible health benefit of dietary antioxidants.

Antioxidants↗

Dietary flavonoids and flavonoid-rich foods are not associated with risk of type 2 diabetes in postmenopausal women.

Flavonoids have anti-inflammatory and antioxidative effects and thus may protect against diabetes. Therefore, we hypothesized that consumption of flavonoids and specific food and beverage sources of flavonoids would be associated with reduced risk of incident diabetes. At baseline (1986), diet (by food frequency questionnaire) and health information were collected from 35,816 postmenopausal women free of diabetes. Self-reported incident diabetes was ascertained 5 times during the study (1987, 1989, 1992, 1997, and 2004). Cox proportional hazards regression was used to calculate hazard ratios for incident diabetes according to categories of total flavonoids and anthocyanidins, flavones, flavanones, flavonols, flavan-3-ol monomers, isoflavones, and proanthocyanidins. Hazard ratios according to intake categories of flavonoid-rich foods and beverages were also calculated (apples, pears, berries, broccoli, bran, citrus, tea, and red wine). Flavonoid consumption was not associated with diabetes risk after multivariable adjustment. Although other flavonoid-rich foods and beverages were not associated, red wine was inversely associated with diabetes. Women who reported drinking red wine >or=1 time/wk had a 16% reduced risk of diabetes than those drinking wine <1 time/wk [HR (95% CI): 0.84 (0.71, 0.99)], with parallel findings for white wine, beer, and liquor. In conclusion, these data do not support a diabetes-protective effect of flavonoids. The suggestive evidence of a protective effect of regular red wine consumption is shared with an inverse association between alcohol drinks in general and diabetes risk and may reflect the effects of nonflavonoid constituents that are common to all alcohol drinks.

Aged↗

Dairy products and ovarian cancer: a pooled analysis of 12 cohort studies.

BACKGROUND: Dairy foods and their constituents (lactose and calcium) have been hypothesized to promote ovarian carcinogenesis. Although case-control studies have reported conflicting results for dairy foods and lactose, several cohort studies have shown positive associations between skim milk, lactose, and ovarian cancer. METHODS: A pooled analysis of the primary data from 12 prospective cohort studies was conducted. The study population consisted of 553,217 women among whom 2,132 epithelial ovarian cases were identified. Study-specific relative risks and 95% confidence intervals were calculated by Cox proportional hazards models and then pooled by a random-effects model. RESULTS: No statistically significant associations were observed between intakes of milk, cheese, yogurt, ice cream, and dietary and total calcium intake and risk of ovarian cancer. Higher lactose intakes comparing > or = 30 versus <10 g/d were associated with a statistically significant higher risk of ovarian cancer, although the trend was not statistically significant (pooled multivariate relative risk, 1.19; 95% confidence interval, 1.01-1.40; P(trend) = 0.19). Associations for endometrioid, mucinous, and serous ovarian cancer were similar to the overall findings. DISCUSSION: Overall, no associations were observed for intakes of specific dairy foods or calcium and ovarian cancer risk. A modest elevation in the risk of ovarian cancer was seen for lactose intake at the level that was equivalent to three or more servings of milk per day. Because a new dietary guideline recommends two to three servings of dairy products per day, the relation between dairy product consumption and ovarian cancer risk at these consumption levels deserves further examination.

Calcium, Dietary↗

Population trends in leisure-time physical activity: Minnesota Heart Survey, 1980-2000.

PURPOSE: Twenty-year trends in lifestyle (leisure, household, and transportation related) physical activity and leisure-time physical activity (LTPA) were evaluated in the Minnesota Heart Survey (MHS), a population-based surveillance study to monitor trends in cardiovascular risk factor levels among residents of the Minneapolis-St. Paul metropolitan area. METHODS: The Minnesota LTPA questionnaire was administered to adult participants in one of five cross-sectional MHS surveys conducted in 1980 (N = 1626), 1985 (N = 2292), 1990 (N = 2552), 1995 (N = 2432), and 2000 (N = 3089). Occupational activity was queried in 1980, 1995, and 2000. Age-adjusted, gender-specific geometric means of lifestyle physical activity and LTPA and of light-, moderate-, and vigorous-intensity activities were calculated for each survey. The proportion of adults participating in regular physical activity for 30 and 60 min x d(-1) was reported. RESULTS: Male gender, younger age, higher educational status, and employment were characteristic of greater participation in physical activity. Daily energy expenditure from lifestyle physical activity and LTPA increased between 1980 and 2000 in both genders, and workplace activity decreased. Using direct questions, the prevalence of men and women participating in 30 or more minutes of physical activity at least five times per week ranged from 8 to 12%, with no time trend. Only 1% of participants participated 60 min daily. Overall, BMI was 1-2 kg x m(-2) lower among individuals who participated regularly in physical activity. CONCLUSIONS: Although energy expenditure was lower than national recommendations, greater physical activity was associated with lower body mass. Public health strategies are needed to facilitate participation in physical activity, especially for women, elderly, and less educated individuals.

Adult↗

Graded associations of blood lead and urinary cadmium concentrations with oxidative-stress-related markers in the U.S. population: results from the third National Health and Nutrition Examination Survey.

Although oxidative stress has been proposed as a mechanism of lead and cadmium toxicity mostly based on in vitro experiments or animal studies, it is uncertain whether this mechanism is relevant in the pathogenesis of lead- or cadmium-related diseases in the general population with low environmental exposure to lead and cadmium. We examined associations of blood lead and urinary cadmium levels with oxidative stress markers of serum gamma-glutamyltransferase (GGT), vitamin C, carotenoids, and vitamin E among 10,098 adult participants in the third U.S. National Health and Nutrition Examination Survey. After adjusting for race, sex, and age (plus serum total cholesterol in the case of serum carotenoids and vitamin E), blood lead and urinary cadmium levels both showed graded associations, positive with serum GGT and inverse with serum vitamin C, carotenoids, and vitamin E (p for trend < 0.01, respectively). These associations were consistently observed among most subgroups: non-Hispanic white, non-Hispanic black, men, women, all age groups, nondrinkers, drinkers, nonsmokers, ex-smokers, current smokers, and body mass index (< 25, 25-29.9, and > or = 30). The strong association of blood lead and urinary cadmium levels with oxidative stress markers in this population suggests that oxidative stress should be considered in the pathogenesis of lead- and cadmium-related diseases even among people with low environmental exposure to lead and cadmium.

Adult↗

A strong dose-response relation between serum concentrations of persistent organic pollutants and diabetes: results from the National Health and Examination Survey 1999-2002.

OBJECTIVE: Low-level exposure to some persistent organic pollutants (POPs) has recently become a focus because of their possible link with the risk of diabetes. RESEARCH DESIGN AND METHODS: Cross-sectional associations of the serum concentrations of POPs with diabetes prevalence were investigated in 2,016 adult participants in the National Health and Nutrition Examination Survey 1999-2002. Six POPs (2,2',4,4',5,5'-hexachlorobiphenyl, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin, oxychlordane, p,p'-dichlorodiphenyltrichloroethane, and trans-nonachlor) were selected, because they were detectable in >or=80% of participants. RESULTS: Compared with subjects with serum concentrations below the limit of detection, after adjustment for age, sex, race and ethnicity, poverty income ratio, BMI, and waist circumference, diabetes prevalence was strongly positively associated with lipid-adjusted serum concentrations of all six POPs. When the participants were classified according to the sum of category numbers of the six POPs, adjusted odds ratios were 1.0, 14.0, 14.7, 38.3, and 37.7 (P for trend < 0.001). The association was consistent in stratified analyses and stronger in younger participants, Mexican Americans, and obese individuals. CONCLUSIONS: There were striking dose-response relations between serum concentrations of six selected POPs and the prevalence of diabetes. The strong graded association could offer a compelling challenge to future epidemiologic and toxicological research.

Adult↗