Developments on a SEM-based X-ray tomography system: Stabilization scheme and performance evaluation

Recent improvements in a SEM-based X-ray tomography system are described. In this type of equipment, X-rays are generated through the interaction between a highly focused electron-beam and a geometrically confined anode target. Unwanted long-term drifts of the e-beam can lead to loss of X-ray flux or decrease of spatial resolution in images. To circumvent this issue, a closed-loop control using FFT-based image correlation is integrated to the acquisition routine, in order to provide an in-line drift correction. The X-ray detection system consists of a state-of-the-art scientific CMOS camera (indirect detection), featuring high quantum efficiency (∼60%) and low read-out noise (∼1.2 electrons). The system performance is evaluated in terms of resolution, detectability, and scanning times for applications covering three different scientific fields: microelectronics, technical textile, and material science.

Main nutrient patterns are associated with prospective weight change in adults from 10 European countries

PURPOSE

Various food patterns have been associated with weight change in adults, but it is unknown which combinations of nutrients may account for such observations. We investigated associations between main nutrient patterns and prospective weight change in adults.

METHODS

This study includes 235,880 participants, 25-70 years old, recruited between 1992 and 2000 in 10 European countries. Intakes of 23 nutrients were estimated from country-specific validated dietary questionnaires using the harmonized EPIC Nutrient DataBase. Four nutrient patterns, explaining 67 % of the total variance of nutrient intakes, were previously identified from principal component analysis. Body weight was measured at recruitment and self-reported 5 years later. The relationship between nutrient patterns and annual weight change was examined separately for men and women using linear mixed models with random effect according to center controlling for confounders.

RESULTS

Mean weight gain was 460 g/year (SD 950) and 420 g/year (SD 940) for men and women, respectively. The annual differences in weight gain per one SD increase in the pattern scores were as follows: principal component (PC) 1, characterized by nutrients from plant food sources, was inversely associated with weight gain in men (-22 g/year; 95 % CI -33 to -10) and women (-18 g/year; 95 % CI -26 to -11). In contrast, PC4, characterized by protein, vitamin B2, phosphorus, and calcium, was associated with a weight gain of +41 g/year (95 % CI +2 to +80) and +88 g/year (95 % CI +36 to +140) in men and women, respectively. Associations with PC2, a pattern driven by many micro-nutrients, and with PC3, a pattern driven by vitamin D, were less consistent and/or non-significant.

CONCLUSIONS

We identified two main nutrient patterns that are associated with moderate but significant long-term differences in weight gain in adults.

The influence of adjustment for energy misreporting on relations of cake and cookie intake with cardiometabolic disease risk factors

BACKGROUND/OBJECTIVES

Previous cohort studies elucidated unexpected inverse relations of cake and cookie (CC) consumption with chronic disease risk. We assessed CC intake in relation to cardiometabolic disease risk factors in a well-phenotyped population with emphasis on misreporting as the potential driving force behind inverse relations.

SUBJECTS/METHODS

In a cross-sectional EPIC-Potsdam sub-study individual usual CC intake was modeled by combining 24 h recall and food frequency questionnaire data. Cardiometabolic risk factors were anthropometry, blood lipids, blood pressure (BP), physical activity and fitness. Analysis of covariance models adjusted for (i) age/education/lifestyle and (ii) additionally for energy misreporting (ratio of energy intake over energy expenditure) were used to compute mean values of risk factors for quartiles of CC intake.

RESULTS

Adjustment for misreporting had considerable impact on relations of CC intake. Initial inverse links with anthropometry were reversed to direct associations. Misreporting adjustment also nullified inverse relations with triglycerides and with total cholesterol in women. Negligible associations with high density lipoprotein cholesterol turned inverse (men: cross-quartile difference (Δ_Q4-Q1)=-1.7 mg/dl; women: Δ_Q4-Q1=-3.6 mg/dl), so did fitness (men: Δ_Q4-Q1=-1.2 ml/kg/min; women: Δ_Q4-Q1=-0.9 ml/kg/min). Direct relations with total/low density lipoprotein cholesterol in men were not changed by misreporting (Δ_Q4-Q1 max. 7.5 or 11.3 mg/dl). Reduced BP was observed in females with increased CC intake; only systolic BP remained relevant after misreporting adjustment (Δ_Q4-Q1=-4.6 mmHg).

CONCLUSIONS

The strong impact of energy misreporting on relations of CC intake with risk factors emphasizes a careful analysis and interpretation of nutritional data. We showed that apparent favorable relations of CC intake changed with a different model specification, highlighting proper modeling considerations when analyzing diet-disease relations.

Diet Quality Scores and Prediction of All-Cause, Cardiovascular and Cancer Mortality in a Pan-European Cohort Study

Scores of overall diet quality have received increasing attention in relation to disease aetiology; however, their value in risk prediction has been little examined. The objective was to assess and compare the association and predictive performance of 10 diet quality scores on 10-year risk of all-cause, CVD and cancer mortality in 451,256 healthy participants to the European Prospective Investigation into Cancer and Nutrition, followed-up for a median of 12.8y. All dietary scores studied showed significant inverse associations with all outcomes. The range of HRs (95% CI) in the top vs. lowest quartile of dietary scores in a composite model including non-invasive factors (age, sex, smoking, body mass index, education, physical activity and study centre) was 0.75 (0.72-0.79) to 0.88 (0.84-0.92) for all-cause, 0.76 (0.69-0.83) to 0.84 (0.76-0.92) for CVD and 0.78 (0.73-0.83) to 0.91 (0.85-0.97) for cancer mortality. Models with dietary scores alone showed low discrimination, but composite models also including age, sex and other non-invasive factors showed good discrimination and calibration, which varied little between different diet scores examined. Mean C-statistic of full models was 0.73, 0.80 and 0.71 for all-cause, CVD and cancer mortality. Dietary scores have poor predictive performance for 10-year mortality risk when used in isolation but display good predictive ability in combination with other non-invasive common risk factors.

Gaussian Graphical Models Identify Networks of Dietary Intake in a German Adult Population

BACKGROUND

Data-reduction methods such as principal component analysis are often used to derive dietary patterns. However, such methods do not assess how foods are consumed in relation to each other. Gaussian graphical models (GGMs) are a set of novel methods that can address this issue.

OBJECTIVE

We sought to apply GGMs to derive sex-specific dietary intake networks representing consumption patterns in a German adult population.

METHODS

Dietary intake data from 10,780 men and 16,340 women of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort were cross-sectionally analyzed to construct dietary intake networks. Food intake for each participant was estimated using a 148-item food-frequency questionnaire that captured the intake of 49 food groups. GGMs were applied to log-transformed intakes (grams per day) of 49 food groups to construct sex-specific food networks. Semiparametric Gaussian copula graphical models (SGCGMs) were used to confirm GGM results.

RESULTS

In men, GGMs identified 1 major dietary network that consisted of intakes of red meat, processed meat, cooked vegetables, sauces, potatoes, cabbage, poultry, legumes, mushrooms, soup, and whole-grain and refined breads. For women, a similar network was identified with the addition of fried potatoes. Other identified networks consisted of dairy products and sweet food groups. SGCGMs yielded results comparable to those of GGMs.

CONCLUSIONS

GGMs are a powerful exploratory method that can be used to construct dietary networks representing dietary intake patterns that reveal how foods are consumed in relation to each other. GGMs indicated an apparent major role of red meat intake in a consumption pattern in the studied population. In the future, identified networks might be transformed into pattern scores for investigating their associations with health outcomes.

Plasma Ascorbic Acid, A Priori Diet Quality Score, and Incident Hypertension: A Prospective Cohort Study

Vitamin C may reduce risk of hypertension, either in itself or by marking a healthy diet pattern. We assessed whether plasma ascorbic acid and the a priori diet quality score relate to incident hypertension and whether they explain each other's predictive abilities. Data were from 2884 black and white adults (43% black, mean age 35 years) initially hypertension-free in the Coronary Artery Risk Development in Young Adults Study (study year 10, 1995-1996). Plasma ascorbic acid was assessed at year 10 and the diet quality score at year 7. Eight-hundred-and-forty cases of hypertension were documented between years 10 and 25. After multiple adjustments, each 12-point (1 SD) higher diet quality score at year 7 related to mean 3.7 μmol/L (95% CI 2.9 to 4.6) higher plasma ascorbic acid at year 10. In separate multiple-adjusted Cox regression models, the hazard ratio of hypertension per 19.6-μmol/L (1 SD) higher ascorbic acid was 0.85 (95% CI 0.79-0.92) and per 12-points higher diet score 0.86 (95% CI 0.79-0.94). These hazard ratios changed little with mutual adjustment of ascorbic acid and diet quality score for each other, or when adjusted for anthropometric variables, diabetes, and systolic blood pressure at year 10. Intake of dietary vitamin C and several food groups high in vitamin C content were inversely related to hypertension, whereas supplemental vitamin C was not. In conclusion, plasma ascorbic acid and the a priori diet quality score independently predict hypertension. This suggests that hypertension risk is reduced by improving overall diet quality and/or vitamin C status. The inverse association seen for dietary but not for supplemental vitamin C suggests that vitamin C status is preferably improved by eating foods rich in vitamin C, in addition to not smoking and other dietary habits that prevent ascorbic acid from depletion.

Fruit and Vegetable Consumption and Changes in Anthropometric Variables in Adult Populations: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

BACKGROUND

Randomized controlled trials provide conflicting results on the effects of increased fruit and vegetable consumption on changes in body weight. We aimed to perform a systematic review and meta-analysis of prospective cohort studies on fruit and vegetable consumption in relation to changes in anthropometric measures.

METHODS

PubMed and EMBASE were searched up to July 2015 for prospective studies reporting on habitual fruit and/or vegetable consumption in relation to changes in body weight or waist circumference or to risk of weight gain/overweight/obesity in adults. Random-effects meta-analysis was applied to pool results across studies.

FINDINGS

Seventeen cohort studies (from 20 reports) including 563,277 participants met our inclusion criteria. Higher intake of fruits was inversely associated with weight change (decrease) (beta-coefficient per 100-g increment, -13.68 g/year; 95% CI, -22.97 to -4.40). No significant changes could be observed for combined fruit and vegetable consumption or vegetable consumption. Increased intake of fruits was inversely associated with changes (decrease) in waist circumference (beta: -0.04 cm/year; 95% CI, -0.05 to -0.02). Comparing the highest combined fruit & vegetable, fruit, and vegetable intake categories were associated with a 9%, 17%, and 17% reduced risk of adiposity (odds ratio [OR]: 0.91, 95% CI, 0.84 to 0.99), (OR: 0.83, 95% CI, 0.71 to 0.99), and (OR: 0.83, 95% CI, 0.70 to 0.99), respectively.

CONCLUSION

This meta-analysis showed several inverse associations between fruit and vegetable intake and prospective improvements in anthropometric parameters, and risk of adiposity. The present meta-analysis seems to be limited by low study quality. Nevertheless, when combined with evolutionary nutrition and epidemiological modeling studies, these findings have public health relevance and support all initiatives to increase fruit and vegetable intake.

Potential Predictors of Plasma Fibroblast Growth Factor 23 Concentrations: Cross-Sectional Analysis in the EPIC-Germany Study

BACKGROUND

Increased fibroblast growth factor 23 (FGF23), a bone-derived hormone involved in the regulation of phosphate and vitamin D metabolism, has been related to the development of cardiovascular disease (CVD) in chronic kidney disease patients and in the general population. However, what determines higher FGF23 levels is still unclear. Also, little is known about the influence of diet on FGF23. The aim of this study was therefore to identify demographic, clinical and dietary correlates of high FGF23 concentrations in the general population.

METHODS

We performed a cross-sectional analysis within a randomly selected subcohort of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Germany comprising 2134 middle-aged men and women. The Human FGF23 (C-Terminal) ELISA kit was used to measure FGF23 in citrate plasma. Dietary data were obtained at baseline via validated food frequency questionnaires including up to 148 food items.

RESULTS

Multivariable adjusted logistic regression showed that men had a 66% lower and smokers a 64% higher probability of having higher FGF23 (≥ 90 RU/mL) levels compared, respectively, with women and nonsmokers. Each doubling in parathyroid hormone, creatinine, and C-reactive protein was related to higher FGF23. Among the dietary factors, each doubling in calcium and total energy intake was related, respectively, to a 1.75 and to a 4.41 fold increased probability of having higher FGF23. Finally, each doubling in the intake of iron was related to an 82% lower probability of having higher FGF23 levels. Results did not substantially change after exclusion of participants with lower kidney function.

CONCLUSIONS

In middle-aged men and women traditional and non-traditional CVD risk factors were related to higher FGF23 concentrations. These findings may contribute to the understanding of the potential mechanisms linking increased FGF23 to increased CVD risk.

Consumption of fatty foods and incident type 2 diabetes in populations from eight European countries

BACKGROUND/OBJECTIVES

Diets high in saturated and trans fat and low in unsaturated fat may increase type 2 diabetes (T2D) risk, but studies on foods high in fat per unit weight are sparse. We assessed whether the intake of vegetable oil, butter, margarine, nuts and seeds and cakes and cookies is related to incident T2D.

SUBJECTS/METHODS

A case-cohort study was conducted, nested within eight countries of the European Prospective Investigation into Cancer (EPIC), with 12,403 incident T2D cases and a subcohort of 16,835 people, identified from a cohort of 340,234 people. Diet was assessed at baseline (1991-1999) by country-specific questionnaires. Country-specific hazard ratios (HRs) across four categories of fatty foods (nonconsumers and tertiles among consumers) were combined with random-effects meta-analysis.

RESULTS

After adjustment not including body mass index (BMI), nonconsumers of butter, nuts and seeds and cakes and cookies were at higher T2D risk compared with the middle tertile of consumption. Among consumers, cakes and cookies were inversely related to T2D (HRs across increasing tertiles 1.14, 1.00 and 0.92, respectively; P-trend <0.0001). All these associations attenuated upon adjustment for BMI, except the higher risk of nonconsumers of cakes and cookies (HR 1.57). Higher consumption of margarine became positively associated after BMI adjustment (HRs across increasing consumption tertiles: 0.93, 1.00 and 1.12; P-trend 0.03). Within consumers, vegetable oil, butter and nuts and seeds were unrelated to T2D.

CONCLUSIONS

Fatty foods were generally not associated with T2D, apart from weak positive association for margarine. The higher risk among nonconsumers of cakes and cookies needs further explanation.

Dietary supplements and risk of cause-specific death, cardiovascular disease, and cancer: a protocol for a systematic review and network meta-analysis of primary prevention trials

BACKGROUND

In the Western world, dietary supplements are commonly used to prevent chronic diseases, mainly cardiovascular disease and cancer. However, there is inconsistent evidence on which dietary supplements actually lower risk of chronic disease, and some may even increase risk. We aim to evaluate the comparative safety and/or effectiveness of dietary supplements for the prevention of mortality (all-cause, cardiovascular, and cancer) and cardiovascular and cancer incidence in primary prevention trials.

METHODS/DESIGN

We will search PubMed, EMBASE, Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Cochrane Central Register of Controlled Trials, clinical trials.gov, and the World Health Organization International Trial Registry Platform. Randomized controlled trials will be included if they meet the following criteria: (1) minimum intervention period of 12 months; (2) primary prevention of chronic disease (is concerned with preventing the onset of diseases and conditions); (3) minimum mean age ≥18 years (maximum mean age 70 years); (4) intervention(s) include vitamins (beta-carotene, vitamin A, B vitamins, Vitamin C, Vitamin D, Vitamin E, and multivitamin supplements); fatty acids (omega-3 fatty acids, omega-6 fatty acids, monounsaturated fat); minerals (magnesium, calcium, selenium, potassium, iron, zinc, copper, iodine; multiminerals); supplements containing combinations of both vitamins and minerals; protein (amino acids); fiber; prebiotics; probiotics; synbiotics; (5) supplements are orally administered as liquids, pills, capsules, tablets, drops, ampoules, or powder; (6) report results on all-cause mortality (primary outcome) and/or mortality from cardiovascular disease or cancer, cardiovascular and/or cancer incidence (secondary outcomes). Pooled effects across studies will be calculated using Bayesian random effects network meta-analysis. Sensitivity analysis will be performed for trials lasting ≥5 years, trials with low risk of bias, trials in elderly people (≥65 years), ethnicity, geographical region, and trials in men and women. The results of the corresponding fixed effects models will also be compared in sensitivity analyses.

DISCUSSION

This is a presentation of the study protocol only. Results and conclusions are pending completion of this study. Our systematic review will be of great value to consumers of supplements, healthcare providers, and policy-makers, regarding the use of dietary supplements.

PROSPERO

CRD42014014801 .

Chocolate-candy consumption and 3-year weight gain among postmenopausal U.S. women

OBJECTIVE

To test the hypothesis that greater chocolate-candy intake is associated with more weight gain in postmenopausal women.

METHODS

A prospective cohort study involved 107,243 postmenopausal American women aged 50-79 years (mean = 60.7) at enrollment in the Women's Health Initiative, with 3-year follow-up. Chocolate-candy consumption was assessed by food frequency questionnaire, and body weight was measured. Linear mixed models, adjusted for demographic, socio economic, anthropomorphic, and behavioral variables, were used to test our main hypotheses.

RESULTS

Compared with women who ate a 1 oz (∼28 g) serving of chocolate candy <1 per month, those who ate this amount 1 per month to <1 per week, 1 per week to < 3 per week and ≥3 per week showed greater 3-year prospective weight gains (kg) of 0.76 (95% CI: 0.66, 0.85), 0.95 (0.84, 1.06), and 1.40 (1.27, 1.53), respectively, (P for linear trend<0.0001). Each additional 1 oz/day was associated with a greater 3-year weight gain (kg) of 0.92 (0.80, 1.05). The weight gain in each chocolate-candy intake level increased as BMI increased above the normal range (18.5-25 kg/m(2)), and was inversely associated with age.

CONCLUSIONS

Greater chocolate-candy intake was associated with greater prospective weight gain in this cohort of postmenopausal women.

Plasma fibroblast growth factor 23 and risk of cardiovascular disease: results from the EPIC-Germany case-cohort study

Increased fibroblast growth factor 23 (FGF23) concentrations have emerged as a novel risk factor for heart failure and stroke but not for myocardial infarction (MI). Yet, most studies on MI were conducted in coronary artery disease (CAD) patients and the elderly. Evidence is unclear in subjects without CAD and for stroke subtypes. We investigated the relationships between FGF23 and overall major cardiovascular endpoints, incident MI, ischemic (IS) and haemorrhagic stroke (HS) in middle-aged adults without pre-existing cardiovascular disease. We used a case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition-Germany, including a randomly drawn subcohort (n = 1,978), incident MI (n = 463) and stroke cases (n = 359 IS; n = 88 HS) identified during a mean follow-up of 8.2 years. Compared with participants with FGF23 levels in the lowest quartile, those in the highest quartile had a 36% increased risk for cardiovascular events [hazard ratio: 1.36, 95% confidence interval (CI): 1.02-1.82] after adjustment for established cardiovascular risk factors, patahyroid hormone and 25-hydroxyvitamin D3 levels, dietary calcium and phosphorus intake, and kidney function. However, sub-analyses revealed significant relationships with risk of MI and HS, but not IS. Compared with the lowest quartile, individuals in the top two FGF23 quartiles had a 1.62 (95% CI 1.07-2.45) fold increased risk for MI and a 2.61 (95% CI 1.23-5.52) fold increase for HS. Increased FGF23 emerged as a risk factor for both MI and HS. Further studies are warranted to confirm these results and to identify underlying mechanisms.

Untargeted metabolic profiling identifies altered serum metabolites of type 2 diabetes mellitus in a prospective, nested case control study

BACKGROUND

Application of metabolite profiling could expand the etiological knowledge of type 2 diabetes mellitus (T2D). However, few prospective studies apply broad untargeted metabolite profiling to reveal the comprehensive metabolic alterations preceding the onset of T2D.

METHODS

We applied untargeted metabolite profiling in serum samples obtained from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort comprising 300 individuals who developed T2D after a median follow-up time of 6 years and 300 matched controls. For that purpose, we used ultraperformance LC-MS with a protocol specifically designed for large-scale metabolomics studies with regard to robustness and repeatability. After multivariate classification to select metabolites with the strongest contribution to disease classification, we applied multivariable-adjusted conditional logistic regression to assess the association of these metabolites with T2D.

RESULTS

Among several alterations in lipid metabolism, there was an inverse association with T2D for metabolites chemically annotated as lysophosphatidylcholine(dm16:0) and phosphatidylcholine(O-20:0/O-20:0). Hexose sugars were positively associated with T2D, whereas higher concentrations of a sugar alcohol and a deoxyhexose sugar reduced the odds of diabetes by approximately 60% and 70%, respectively. Furthermore, there was suggestive evidence for a positive association of the circulating purine nucleotide isopentenyladenosine-5'-monophosphate with incident T2D.

CONCLUSIONS

This study constitutes one of the largest metabolite profiling approaches of T2D biomarkers in a prospective study population. The findings might help generate new hypotheses about diabetes etiology and develop further targeted studies of a smaller number of potentially important metabolites.

Relationship between N-terminal pro-brain natriuretic peptide, obesity and the risk of heart failure in middle-aged German adults

Background

Both high concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) and obesity are related to higher heart failure risk. However, inverse relationships between NT-proBNP and obesity have been reported. Therefore, it was investigated whether the association between NT-proBNP and the risk of heart failure differed according to obesity status.

Methods

A case-cohort study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam, comprising a random sub-cohort (non-cases = 1,150, cases = 13, mean age: 50.5±9.0 years) and heart failure cases outside the sub-cohort (n = 197). Weighted Cox proportional hazards regression was used to examine the association between NT-proBNP and heart failure risk during a mean follow-up time of 8 years. Stratified analyses were performed according to obesity status as defined by body mass index (<30 kg/m² versus ≥30 kg/m²).

Results

Overall, NT-proBNP was associated with higher risk of heart failure after multivariable adjustment (hazard ratio (HR) and 95% confidence interval (CI): 2.56 (1.49–4.41) for the top versus bottom tertile of NT-proBNP, p_trend:<0.01). In stratified analyses, the shape of association was linear in non-obese and U-shaped in obese participants: HRs (95%CI) from the first to the third tertile of NT-proBNP for non-obese: reference, 1.72 (0.85–3.49), 2.72 (1.42–5.22), and for obese: 3.29 (1.04–10.40), reference, 3.74 (1.52–9.21).

Conclusions

Although high circulating concentrations of NT-proBNP were positively associated with incident heart failure in the entire sample, the association differed according to obesity status. In obese, an increased risk of heart failure was also observed in those with low NT-proBNP concentrations. If confirmed, this observation warrants further investigation to understand underlying pathophysiological mechanisms.

Prediagnostic circulating vitamin D levels and risk of hepatocellular carcinoma in European populations: a nested case-control study

The association between vitamin D status and hepatocellular carcinoma (HCC) has not been well investigated, despite experimental evidence supporting an important role of vitamin D in liver pathophysiology. Our objective was to investigate the association between prediagnostic circulating 25-hydroxyvitamin D [25(OH)D] serum levels and the risk of HCC in a prospective, nested case-control study among 520,000 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Each case (n = 138) diagnosed between 1992 and 2010 was matched to one control by age, sex, study center, date and time of blood collection, and fasting status. Serum baseline levels of 25(OH)D were measured by liquid chromatography/tandem mass spectrometry. Multivariable incident rate ratios (IRRs) of HCC associated with continuous (per 10 nmol/L) or categorical levels (tertiles or a priori-defined categories) of prediagnostic 25(OH)D were calculated using conditional logistic regression. Higher 25(OH)D levels were associated with a 49% reduction in the risk of HCC (highest versus lowest tertile: multivariable IRR = 0.51, 95% confidence interval [CI], 0.26 to 0.99; Ptrend  = 0.04; per 10 nmol/L increase: IRR = 0.80, 95% CI, 0.68-0.94). The finding did not vary substantially by time from enrolment to diagnosis, and did not change after adjustment for biomarkers of preexisting liver damage, nor chronic infection with hepatitis B or C viruses. The findings were not modified by body size or smoking status.

CONCLUSION

In this prospective study on western European populations, serum levels of 25(OH)D were inversely associated with the risk of HCC. Given the rising incidence of this cancer in low-risk developed countries and the strong public health interest surrounding the potentially cancer-protective roles of vitamin D, additional studies in different populations are required.

Nutrient patterns and their food sources in an International Study Setting: report from the EPIC study

BACKGROUND

Compared to food patterns, nutrient patterns have been rarely used particularly at international level. We studied, in the context of a multi-center study with heterogeneous data, the methodological challenges regarding pattern analyses.

METHODOLOGY/PRINCIPAL FINDINGS

We identified nutrient patterns from food frequency questionnaires (FFQ) in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study and used 24-hour dietary recall (24-HDR) data to validate and describe the nutrient patterns and their related food sources. Associations between lifestyle factors and the nutrient patterns were also examined. Principal component analysis (PCA) was applied on 23 nutrients derived from country-specific FFQ combining data from all EPIC centers (N = 477,312). Harmonized 24-HDRs available for a representative sample of the EPIC populations (N = 34,436) provided accurate mean group estimates of nutrients and foods by quintiles of pattern scores, presented graphically. An overall PCA combining all data captured a good proportion of the variance explained in each EPIC center. Four nutrient patterns were identified explaining 67% of the total variance: Principle component (PC) 1 was characterized by a high contribution of nutrients from plant food sources and a low contribution of nutrients from animal food sources; PC2 by a high contribution of micro-nutrients and proteins; PC3 was characterized by polyunsaturated fatty acids and vitamin D; PC4 was characterized by calcium, proteins, riboflavin, and phosphorus. The nutrients with high loadings on a particular pattern as derived from country-specific FFQ also showed high deviations in their mean EPIC intakes by quintiles of pattern scores when estimated from 24-HDR. Center and energy intake explained most of the variability in pattern scores.

CONCLUSION/SIGNIFICANCE

The use of 24-HDR enabled internal validation and facilitated the interpretation of the nutrient patterns derived from FFQs in term of food sources. These outcomes open research opportunities and perspectives of using nutrient patterns in future studies particularly at international level.

Plasma fibroblast growth factor 23, parathyroid hormone, 25-hydroxyvitamin D3, and risk of heart failure: a prospective, case-cohort study

CONTEXT

Bone mineral metabolism may play a role in the development of heart failure (HF).

OBJECTIVE

The aim of the study was to investigate the relationships of plasma fibroblast growth factor (FGF) 23, PTH, and 25-hydroxyvitamin D3 [25(OH)D3] with incident congestive HF in a population-based cohort of men and women aged 40-65 and 35-65 years, respectively, at baseline.

DESIGN

We conducted a prospective case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort, including a randomly drawn sample of the total cohort free of HF and all incident HF cases that occurred during a mean follow-up of 8.2 ± 1.6 years.

PARTICIPANTS AND SETTING

A total of 221 incident congestive HF cases and 1228 individuals free of HF were included in the study.

MAIN OUTCOME MEASURES

Incident congestive HF was measured.

RESULTS

In a multivariable model, each doubling of FGF23 [ie, per log (base 2) unit higher FGF23] was associated with a 29% higher HF risk (hazard ratio, 1.29 [95% confidence interval (CI), 1.07-1.56]). After multivariable adjustment, including estimated glomerular filtration rate, PTH was not related to HF risk (hazard ratio per doubling of PTH, 1.21 [95% CI, 0.99-1.48]). However, an interaction was observed between PTH and obesity, suggesting a relationship with HF risk in obese, but not in nonobese individuals. The hazard ratio for HF per doubling of 25(OH)D3 was 1.02 (95% CI, 0.73-1.41).

CONCLUSIONS

Our findings provide epidemiological evidence for a positive relationship between FGF23 and risk of HF. The role of PTH in the development of HF remains unclear, in particular in obese individuals, until further confirmation in other studies. 25(OH)D3 was not related to HF.

Dietary intakes of individual flavanols and flavonols are inversely associated with incident type 2 diabetes in European populations

Dietary flavanols and flavonols, flavonoid subclasses, have been recently associated with a lower risk of type 2 diabetes (T2D) in Europe. Even within the same subclass, flavonoids may differ considerably in bioavailability and bioactivity. We aimed to examine the association between individual flavanol and flavonol intakes and risk of developing T2D across European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study was conducted in 8 European countries across 26 study centers with 340,234 participants contributing 3.99 million person-years of follow-up, among whom 12,403 incident T2D cases were ascertained and a center-stratified subcohort of 16,154 individuals was defined. We estimated flavonoid intake at baseline from validated dietary questionnaires using a database developed from Phenol-Explorer and USDA databases. We used country-specific Prentice-weighted Cox regression models and random-effects meta-analysis methods to estimate HRs. Among the flavanol subclass, we observed significant inverse trends between intakes of all individual flavan-3-ol monomers and risk of T2D in multivariable models (all P-trend < 0.05). We also observed significant trends for the intakes of proanthocyanidin dimers (HR for the highest vs. the lowest quintile: 0.81; 95% CI: 0.71, 0.92; P-trend = 0.003) and trimers (HR: 0.91; 95% CI: 0.80, 1.04; P-trend = 0.07) but not for proanthocyanidins with a greater polymerization degree. Among the flavonol subclass, myricetin (HR: 0.77; 95% CI: 0.64, 0.93; P-trend = 0.001) was associated with a lower incidence of T2D. This large and heterogeneous European study showed inverse associations between all individual flavan-3-ol monomers, proanthocyanidins with a low polymerization degree, and the flavonol myricetin and incident T2D. These results suggest that individual flavonoids have different roles in the etiology of T2D.

Dietary vitamin D intake and risk of type 2 diabetes in the European Prospective Investigation into Cancer and Nutrition: the EPIC-InterAct study

BACKGROUND/OBJECTIVES

Prospective cohort studies have indicated that serum vitamin D levels are inversely related to risk of type 2 diabetes. However, such studies cannot determine the source of vitamin D. Therefore, we examined the association of dietary vitamin D intake with incident type 2 diabetes within the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct study in a heterogeneous European population including eight countries with large geographical variation.

SUBJECTS/METHODS

Using a case-cohort design, 11,245 incident cases of type 2 diabetes and a representative subcohort (N=15,798) were included in the analyses. Hazard ratios (HR) and 95% confidence intervals (CIs) for type 2 diabetes were calculated using a Prentice-weighted Cox regression adjusted for potential confounders. Twenty-four-hour diet-recall data from a subsample (N=2347) were used to calibrate habitual intake data derived from dietary questionnaires.

RESULTS

Median follow-up time was 10.8 years. Dietary vitamin D intake was not significantly associated with the risk of type 2 diabetes. HR and 95% CIs for the highest compared to the lowest quintile of uncalibrated vitamin D intake was 1.09 (0.97-1.22) (Ptrend=0.17). No associations were observed in a sex-specific analysis. The overall pooled effect (HR (95% CI)) using the continuous calibrated variable was 1.00 (0.97-1.03) per increase of 1 μg/day dietary vitamin D.

CONCLUSIONS

This observational study does not support an association between higher dietary vitamin D intake and type 2 diabetes incidence. This result has to be interpreted in light of the limited contribution of dietary vitamin D on the overall vitamin D status of a person.

Dietary intake of vitamin D and calcium and breast cancer risk in the European Prospective Investigation into Cancer and Nutrition

Studies assessing the effects of vitamin D or calcium intake on breast cancer risk have been inconclusive. Furthermore, few studies have evaluated them jointly. This study is the largest so far examining the association of dietary vitamin D and calcium intake with breast cancer risk in the European Prospective Investigation into Cancer and Nutrition. During a mean follow-up of 8.8 yr, 7760 incident invasive breast cancer cases were identified among 319,985 women. Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for pre- and postmenopausal breast cancer risk. Comparing the highest with the lowest quintile of vitamin D intake, HR and 95% CI were 1.07 (0.87-1.32) and 1.02 (0.90-1.16) for pre- and postmenopausal women, respectively. The corresponding HR and 95% CIs for calcium intake were 0.98 (0.80-1.19) and 0.90 (0.79-1.02), respectively. For calcium intake in postmenopausal women, the test for trend was borderline statistically significant (P(trend) = 0.05). There was no significant interaction between vitamin D and calcium intake and cancer risk (P(interaction) = 0.57 and 0.22 in pre- and postmenopausal women, respectively). In this large prospective cohort, we found no evidence for an association between dietary vitamin D or calcium intake and breast cancer risk.

The association between dietary flavonoid and lignan intakes and incident type 2 diabetes in European populations: the EPIC-InterAct study

OBJECTIVE

To study the association between dietary flavonoid and lignan intakes, and the risk of development of type 2 diabetes among European populations.

RESEARCH DESIGN AND METHODS

The European Prospective Investigation into Cancer and Nutrition-InterAct case-cohort study included 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 participants from among 340,234 participants with 3.99 million person-years of follow-up in eight European countries. At baseline, country-specific validated dietary questionnaires were used. A flavonoid and lignan food composition database was developed from the Phenol-Explorer, the U.K. Food Standards Agency, and the U.S. Department of Agriculture databases. Hazard ratios (HRs) from country-specific Prentice-weighted Cox regression models were pooled using random-effects meta-analysis.

RESULTS

In multivariable models, a trend for an inverse association between total flavonoid intake and type 2 diabetes was observed (HR for the highest vs. the lowest quintile, 0.90 [95% CI 0.77-1.04]; P value trend = 0.040), but not with lignans (HR 0.88 [95% CI 0.72-1.07]; P value trend = 0.119). Among flavonoid subclasses, flavonols (HR 0.81 [95% CI 0.69-0.95]; P value trend = 0.020) and flavanols (HR 0.82 [95% CI 0.68-0.99]; P value trend = 0.012), including flavan-3-ol monomers (HR 0.73 [95% CI 0.57-0.93]; P value trend = 0.029), were associated with a significantly reduced hazard of diabetes.

CONCLUSIONS

Prospective findings in this large European cohort demonstrate inverse associations between flavonoids, particularly flavanols and flavonols, and incident type 2 diabetes. This suggests a potential protective role of eating a diet rich in flavonoids, a dietary pattern based on plant-based foods, in the prevention of type 2 diabetes.

Adiponectin and risk of stroke: prospective study and meta-analysis

BACKGROUND AND PURPOSE

The favorable cardiovascular effects attributed to adiponectin may lower risk of stroke. We investigated this in a prospective study and meta-analysis.

METHODS

A case-cohort study nested within the Potsdam cohort of the European Prospective Investigation into Cancer was performed, with 170 incident cases of ischemic stroke and a randomly selected subcohort of 2155 participants without major cardiovascular disease at baseline. A random-effects dose-response meta-analysis was performed on prospective studies reporting on adiponectin and incident stroke in healthy populations up to April 2013, identified through MEDLINE and EMBASE.

RESULTS

In European Prospective Investigation into Cancer-Potsdam, after adjustment for cardiovascular risk factors, the hazard ratio of ischemic stroke per 5-µg/mL higher total-adiponectin was 1.10 (95% confidence interval, 0.89-1.37). Participants with higher total-adiponectin had higher high-density lipoprotein-cholesterol and lower high-sensitivity C-reactive protein and triglyceride levels, and had less often diabetes mellitus. Additional adjustment for these putative mediators yielded a hazard ratio of 1.31 (95% confidence interval, 1.04-1.64). Nine studies (19,259 participants, 2960 cases), including European Prospective Investigation into Cancer-Potsdam, were meta-analyzed. Pooling relative risks adjusted for cardiovascular risk factors not including putative mediators indicated moderate between-study heterogeneity (I2=52.2%). This was explained by the smallest study, and the pooled relative risk (95% confidence interval) before and after its exclusion was 1.03 (0.98-1.08) and 0.99 (0.96-1.01) per 5 µg/mL, respectively. The pooled relative risk (95% confidence interval) additionally adjusted for potential mediators was 1.08 (1.01-1.15) and 1.05 (1.00-1.11) before and after excluding the same study, respectively.

CONCLUSIONS

Adiponectin is not associated with risk of stroke. If anything, adiponectin relates directly to stroke risk after controlling for risk factors that favorably correlate with adiponectin.

Dietary, lifestyle, and genetic determinants of vitamin D status: a cross-sectional analysis from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Germany study

PURPOSE

Considerable variation in 25-hydroxyvitamin D (25(OH)D) in populations worldwide that seems to be independent of latitude has been reported. Therefore, we aimed to assess vitamin D status of a mid-aged German general population and to identify its dietary, lifestyle, anthropometric, and genetic determinants.

METHODS

25(OH)D concentrations were measured by LC-MS/MS in plasma samples of a random subcohort of the German arm of the European Prospective Investigation into Cancer and Nutrition (EPIC) comprising 2,100 subjects aged 35-65 years. Associations between potential predictors and 25(OH)D were assessed by linear regression models.

RESULTS

32.8% of the variance in 25(OH)D was explained by a multivariable regression model, with season being the by far strongest predictor (semi-partial R²: 14.6%). Sex, waist circumference, leisure time physical activity, smoking, polymorphisms in the GC, CYP2R1, and DHCR7 genes, supplement use, exogenous hormone use, alcohol consumption, egg consumption, and fish consumption were significantly associated with 25(OH)D concentrations as well. However, none of these factors explained >2.3% of the variance in 25(OH)D.

CONCLUSION

Even with a comprehensive set of genetic, anthropometric, dietary, and lifestyle correlates, not more than 32.8% of the variation in 25(OH)D could be explained in the EPIC-Germany study, implying that vitamin D prediction scores may not provide an appropriate proxy for measured 25(OH)D. Food intake was only a weak predictor of 25(OH)D concentrations, while a strong seasonal fluctuation in 25(OH)D was shown.

Plasma 25-hydroxyvitamin D concentration and lymphoma risk: results of the European Prospective Investigation into Cancer and Nutrition

BACKGROUND

The relation between vitamin D status and lymphoma risk is inconclusive.

OBJECTIVE

We examined the association between prediagnostic plasma 25-hydroxyvitamin D [25(OH)D] and lymphoid cancer risk.

DESIGN

We conducted a study nested within the European Prospective Investigation into Cancer and Nutrition cohort of 1127 lymphoma cases and 1127 matched controls with a mean follow-up time of 7.1 y. Conditional logistic regression was used to estimate multivariable-adjusted incidence rate ratios of lymphoma risk in relation to plasma 25(OH)D. Season-standardized and season-specific 25(OH)D quartiles were used. We also analyzed 25(OH)D as a continuous variable and used predefined cutoffs.

RESULTS

No statistically significant association between plasma 25(OH)D and overall lymphoid cancer risk was observed. A positive association for B-cell non-Hodgkin lymphoma was noted only in those with a diagnosis made during the first 2 y of follow-up (P-heterogeneity = 0.03), which suggests the possibility of reverse causality. Further analysis restricted to participants with ≥2 y of follow-up time showed a significant association between 25(OH)D and chronic lymphocytic leukemia (CLL) (n = 161): adjusted incidence rate ratios were 0.40 (95% CI: 0.18, 0.90; P-trend = 0.05) and 0.31 (95% CI: 0.13, 0.76; P-trend = 0.03) for the top compared with the bottom season-standardized and season-specific quartiles, respectively. Data on dietary vitamin D intake provided further support for the observed association (incidence rate ratio: 0.33; 95% CI = 0.12, 0.89; P-trend = 0.006).

CONCLUSIONS

Our findings do not support a protective role of high 25(OH)D concentration in lymphoid cancers overall. However, they suggest that higher concentrations of 25(OH)D are associated with a reduced risk of CLL.

Habitual chocolate consumption may increase body weight in a dose-response manner

OBJECTIVE

Habitual chocolate intake was recently found to be associated with lower body weight in three cross-sectional epidemiological studies. Our objective was to assess whether these cross-sectional results hold up in a more rigorous prospective analysis.

METHODS

We used data from the Atherosclerosis Risk in Communities cohort. Usual dietary intake was assessed by questionnaire at baseline (1987-98), and after six years. Participants reported usual chocolate intake as the frequency of eating a 1-oz (~28 g) serving. Body weight and height were measured at the two visits. Missing data were replaced by multiple imputation. Linear mixed-effects models were used to evaluate cross-sectional and prospective associations between chocolate intake and adiposity.

RESULTS

Data were from 15,732 and 12,830 participants at the first and second visit, respectively. More frequent chocolate consumption was associated with a significantly greater prospective weight gain over time, in a dose-response manner. For instance, compared to participants who ate a chocolate serving less often than monthly, those who ate it 1-4 times a month and at least weekly experienced an increase in Body Mass Index (kg/m2) of 0.26 (95% CI 0.08, 0.44) and 0.39 (0.23, 0.55), respectively, during the six-year study period. In cross-sectional analyses the frequency of chocolate consumption was inversely associated with body weight. This inverse association was attenuated after excluding participants with preexisting obesity-related illness. Compared to participants without such illness, those with it had higher BMI and reported less frequent chocolate intake, lower caloric intake, and diets richer in fruits and vegetables. They tended to make these dietary changes after becoming ill.

CONCLUSIONS

Our prospective analysis found that a chocolate habit was associated with long-term weight gain, in a dose-response manner. Our cross-sectional finding that chocolate intake was associated with lower body weight did not apply to participants without preexisting serious illness.

Plasma 25-hydroxyvitamin D and its genetic determinants in relation to incident myocardial infarction and stroke in the European prospective investigation into cancer and nutrition (EPIC)-Germany study

Circulating 25-hydroxyvitamin D (25(OH)D) has been associated with cardiovascular disease (CVD) risk in observational studies. Also, SNPs to explain variation in 25(OH)D have been identified by genome-wide association studies. Detection of direct associations between SNPs that significantly affect 25(OH)D and CVD risk would indicate a causal role of vitamin D, as reverse causation could be excluded and confounding could be better controlled. Thus, a combined analysis of candidate SNPs in relation to circulating 25(OH)D and CVD risk was carried out. A case-cohort study within the EPIC-Germany study was conducted comprising a randomly drawn subcohort of 2,132 subjects (57.9% women, mean age: 50.6 years) and incident cases of myocardial infarction (n=559) and stroke (n=471) that occurred during a mean follow-up duration of 7.6 years. 25(OH)D concentrations were measured by LC-MS/MS in baseline plasma samples. Additionally, eight candidate SNPs were assayed. Associations between 25(OH)D, SNPs and the risks of myocardial infarction and stroke were assessed by multivariable regression analyses. Mean 25(OH)D level was 47.2 nmol/L in the subcohort. Four SNPs were associated with 25(OH)D (p<0.05). In subjects with 25(OH)D levels <25 nmol/L, the risks of CVD as composite endpoint (Hazard Ratio: 1.53, 95% confidence interval: 1.12–2.09), myocardial infarction, and stroke were significantly increased compared to subjects with levels ≥50 nmol/L, while no significant linear associations were observed. A SNP score was not related to the risks of total CVD (Hazard Ratio: 1.0, 95% confidence interval: 0.71–1.42), myocardial infarction, or stroke. The same was true concerning single SNPs. Given the lack of association between SNPs and the risks of stroke and myocardial infarction, the present findings do not point to a major causal role of vitamin D in the development of these diseases. However, a detection of modest associations between genetic markers and CVD risk in larger consortia cannot be ruled out.

Adult weight change and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition

AIM

Weight change during adult life may reflect metabolic changes and influence colorectal cancer (CRC) development, but such role is not well established. We aimed to explore the association between adult weight change (from age 20 to 50) and CRC risk. In particular, we investigated differences according to colon and rectal cancer, sex and measures of attained adiposity.

METHODS

We included 201,696 participants from six participating countries in the European Prospective Investigation into Cancer and Nutrition (1992-2010). During a mean follow-up of 11.2 years 2384 (1194 in men and 1190 in women) incident CRC cases occurred. Cox proportional hazard models adjusted for body mass index at age 20 and lifestyle factors at study recruitment were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

After multivariable adjustment, each kg of weight gained annually from age 20 to 50 was associated with a 60% higher risk of colon cancer (95% CI 1.20-2.09), but not rectal cancer (HR 1.13, 95% CI 0.79-1.62, P(interaction)=0.04). The higher risk of colon cancer was restricted to people with high attained waist circumference at age 50 (HR 1.82, 95%CI 1.14-2.91, P(interaction)=0.02). Results were not different in men and women (P(interaction)=0.81).

CONCLUSION(S)

Adult weight gain, as reflected by attained abdominal obesity at age 50, increases colon cancer risk in both men and women. These data underline the importance of weight management and metabolic health maintenance in early adult life years for colon cancer prevention.

Vitamin C transporter gene (SLC23A1 and SLC23A2) polymorphisms, plasma vitamin C levels, and gastric cancer risk in the EPIC cohort

Vitamin C is known to protect mucosal tissues from oxidative stress and inhibit nitrosamine formation in the stomach. High consumption of fruits, particularly citrus, and higher circulating vitamin C concentrations may be inversely associated with gastric cancer (GC) risk. We investigated 20 polymorphisms in vitamin C transporter genes SCL23A1 and SCL23A2 and GC risk in 365 cases and 1,284 controls nested within the European Prospective Investigation into Cancer and Nutrition cohort. We also evaluated the association between these polymorphisms and baseline plasma vitamin C levels in a subset of participants. Four SNPs were predictors of plasma vitamin C levels (SLC23A1 rs11950646 and rs33972313; SLC23A2 rs6053005 and rs6133175) in multivariable linear regression models. One SNP (SLC23A2 rs6116569) was associated with GC risk, in particular non-cardia GC (OR = 1.63, 95 % CI = 1.11-2.39, based on 178 non-cardia cases), but this association was attenuated when plasma vitamin C was included in the logistic regression model. Haplotype analysis of SLC23A1 yielded no associations with GC. In SLC23A2, one haplotype was associated with both overall and non-cardia GC, another haplotype was associated with GC overall, and a third was associated with intestinal-type GC. Common variants in SLC23A1 and SLC23A2 may influence plasma vitamin C concentration independent of dietary intake, and variation in SLC23A2 may influence GC risk. Additional prospective studies in large populations and consortia are recommended. Investigation of variation in vitamin C transporter genes may shed light on the preventative properties of vitamin C in gastric carcinogenesis.

Mediterranean diet and colorectal cancer risk: results from a European cohort

The authors investigated the association of adherence to Mediterranean diet with colorectal cancer (CRC) risk in the European Prospective Investigation into Cancer and nutrition study. Adherence to Mediterranean diet was expressed through two 10-unit scales, the Modified Mediterranean diet score (MMDS) and the Centre-Specific MMDS (CSMMDS). Both scales share the same dietary components but differ in the cut-off values that were used for these components in the construction of the scales. Adjusted hazard ratios (HR) for the associations of these scales with CRC incidence were estimated. After 5,296,617 person-years of follow-up, 4,355 incident CRC cases were identified. A decreased risk of CRC, of 8 and 11 % was estimated when comparing the highest (scores 6-9) with the lowest (scores 0-3) adherence to CSMMDS and MMDS respectively. For MMDS the HR was 0.89 (95 % confidence interval (CI): 0.80, 0.99). A 2-unit increment in either Mediterranean scale was associated with a borderline statistically significant 3 to 4 % reduction in CRC risk (HR for MMDS: 0.96; 95 % CI: 0.92, 1.00). These associations were somewhat more evident, among women, were mainly manifested for colon cancer risk and their magnitude was not altered when alcohol was excluded from MMDS. These findings suggest that following a Mediterranean diet may have a modest beneficial effect on CRC risk.

Liver enzymes and stroke risk in middle-aged German adults

OBJECTIVE

To investigate the association between the liver enzymes γ-glutamyltransferase (GGT) and (alanine aminotransferase) ALT and risk of stroke, its subtypes including TIA as well as fatal and non-fatal events.

METHODS

A case-cohort study within the European Prospective Investigation into Cancer and Nutrition-Potsdam Study comprising 27548 middle-aged subjects was designed. GGT and ALT were measured in plasma of 353 individuals who developed a stroke and in 2110 individuals who remained free of cardiovascular events during a mean follow-up of 8.2 ± 2.2 years. Cox proportional-hazard models were applied to evaluate the association between liver enzymes and stroke risk.

RESULTS

After adjustment for established clinical and lifestyle factors, a 1 unit change in naturally logged GGT was related to a 1.20 (95%CI: 1.03-1.40) increased stroke risk. Risk estimates did not significantly differ between fatal (Relative Risk (RR) = 1.35, 95%CI: 1.14-1.61) and non-fatal events (RR = 1.15; 95%CI: 0.97-1.36). ALT was not associated with overall stroke risk (RR = 0.95; 95%CI: 0.71-1.26). However, in subtype analyses we observed in multivariable adjusted models a significant increased risk of hemorrhagic stroke (RR = 2.00; 95% CI: 1.01-3.96), but decreased risk of ischemic stroke (RR = 0.66; 95%CI: 0.44-0.998).

CONCLUSIONS

Our data provide further evidence for a link between GGT, but not ALT and overall stroke suggesting that these biomarkers are involved in different pathways of disease development. Further studies are needed to clarify the putative relationships between ALT and subtypes of stroke.

Macronutrient composition of the diet and prospective weight change in participants of the EPIC-PANACEA study

BACKGROUND

The effect of the macronutrient composition of the usual diet on long term weight maintenance remains controversial.

METHODS

373,803 subjects aged 25-70 years were recruited in 10 European countries (1992-2000) in the PANACEA project of the EPIC cohort. Diet was assessed at baseline using country-specific validated questionnaires and weight and height were measured at baseline and self-reported at follow-up in most centers. The association between weight change after 5 years of follow-up and the iso-energetic replacement of 5% of energy from one macronutrient by 5% of energy from another macronutrient was assessed using multivariate linear mixed-models. The risk of becoming overweight or obese after 5 years was investigated using multivariate Poisson regressions stratified according to initial Body Mass Index.

RESULTS

A higher proportion of energy from fat at the expense of carbohydrates was not significantly associated with weight change after 5 years. However, a higher proportion of energy from protein at the expense of fat was positively associated with weight gain. A higher proportion of energy from protein at the expense of carbohydrates was also positively associated with weight gain, especially when carbohydrates were rich in fibre. The association between percentage of energy from protein and weight change was slightly stronger in overweight participants, former smokers, participants ≥60 years old, participants underreporting their energy intake and participants with a prudent dietary pattern. Compared to diets with no more than 14% of energy from protein, diets with more than 22% of energy from protein were associated with a 23-24% higher risk of becoming overweight or obese in normal weight and overweight subjects at baseline.

CONCLUSION

Our results show that participants consuming an amount of protein above the protein intake recommended by the American Diabetes Association may experience a higher risk of becoming overweight or obese during adult life.

Physical Activity and Mortality in Individuals With Diabetes Mellitus: A Prospective Study and Meta-analysis

BACKGROUND Physical activity (PA) is considered a cornerstone of diabetes mellitus management to prevent complications, but conclusive evidence is lacking. METHODS This prospective cohort study and meta-analysis of existing studies investigated the association between PA and mortality in individuals with diabetes. In the EPIC study (European Prospective Investigation Into Cancer and Nutrition), a cohort was defined of 5859 individuals with diabetes at baseline. Associations of leisure-time and total PA and walking with cardiovascular disease (CVD) and total mortality were studied using multivariable Cox proportional hazards regression models. Fixed- and random-effects meta-analyses of prospective studies published up to December 2010 were pooled with inverse variance weighting. RESULTS In the prospective analysis, total PA was associated with lower risk of CVD and total mortality. Compared with physically inactive persons, the lowest mortality risk was observed in moderately active persons: hazard ratios were 0.62 (95% CI, 0.49-0.78) for total mortality and 0.51 (95% CI, 0.32-0.81) for CVD mortality. Leisure-time PA was associated with lower total mortality risk, and walking was associated with lower CVD mortality risk. In the meta-analysis, the pooled random-effects hazard ratio from 5 studies for high vs low total PA and all-cause mortality was 0.60 (95% CI, 0.49-0.73). CONCLUSIONS Higher levels of PA were associated with lower mortality risk in individuals with diabetes. Even those undertaking moderate amounts of activity were at appreciably lower risk for early death compared with inactive persons. These findings provide empirical evidence supporting the widely shared view that persons with diabetes should engage in regular PA.

Microsomal triglyceride transfer protein -164 T > C gene polymorphism and risk of cardiovascular disease: results from the EPIC-Potsdam case-cohort study

Background

The microsomal triglyceride transfer protein (MTTP) is encoded by the MTTP gene that is regulated by cholesterol in humans. Previous studies investigating the effect of MTTP on ischemic heart disease have produced inconsistent results. Therefore, we have tested the hypothesis that the rare allele of the -164T > C polymorphism in MTTP alters the risk of cardiovascular disease (CVD), depending on the cholesterol levels.

Methods

The -164T > C polymorphism was genotyped in a case-cohort study (193 incident myocardial infarction (MI) and 131 incident ischemic stroke (IS) cases and 1 978 non-cases) nested within the European Prospective Investigation into Cancer and Nutrition (EPIC)–Potsdam study, comprising 27 548 middle-aged subjects. The Heinz Nixdorf Recall study (30 CVD cases and 1 188 controls) was used to replicate our findings.

Results

Genotype frequencies were not different between CVD and CVD free subjects (P = 0.79). We observed an interaction between the -164T > C polymorphism and total cholesterol levels in relation to future CVD. Corresponding stratified analyses showed a significant increased risk of CVD (HR_additve = 1.38, 95% CI: 1.07 to 1.78) for individuals with cholesterol levels <200 mg/dL in the EPIC-Potsdam study. HR_additive was 1.06, 95% CI: 0.33 to 3.40 for individuals in the Heinz Nixdorf Recall study. A borderline significant decrease in CVD risk was observed in subjects with cholesterol levels ≥200 mg/dL (HR_additve = 0.77, 95% CI: 0.58 to 1.03) in the EPIC-Potsdam study. A similar trend was observed in the independent cohort (HR_additve = 0.60, 95% CI: 0.29 to 1.25).

Conclusions

Our study suggests an interaction between MTTP -164T > C functional polymorphism with total cholesterol levels. Thereby risk allele carriers with low cholesterol levels may be predisposed to an increased risk of developing CVD, which seems to be abolished among risk allele carriers with high cholesterol levels.

Heterogeneity of the Stearoyl-CoA desaturase-1 (SCD1) gene and metabolic risk factors in the EPIC-Potsdam study

BACKGROUND

Stearoyl-CoA desaturase-1 (SCD1) is an enzyme involved in lipid metabolism. In mice and humans its activity has been associated with traits of the metabolic syndrome, but also with the prevention of saturated fatty acids accumulation and subsequent inflammation, whereas for liver fat content inconsistent results have been reported. Thus, variants of the gene encoding SCD1 (SCD1) could potentially modify metabolic risk factors, but few human studies have addressed this question.

METHODS

In a sample of 2157 middle-aged men and women randomly drawn from the Potsdam cohort of the European Prospective Investigation into Cancer and Nutrition, we investigated the impact of 7 SCD1 tagging-single nucleotide polymorphisms (rs1502593, rs522951, rs11190480, rs3071, rs3793767, rs10883463 and rs508384) and 5 inferred haplotypes with frequency >5% describing 90.9% of the genotype combinations in our population, on triglycerides, body mass index (BMI), waist circumference (WC), glycated haemoglobin (HbA1c), high-sensitivity C-reactive protein (hs-CRP), gamma-glutamyltransferase (GGT), alanine aminotransferase (ALT) and fetuin-A.

RESULTS

No significant associations between any of the SNPs or haplotypes and BMI, WC, fetuin-A and hs-CRP were observed. Associations of rs10883463 with triglycerides, GGT and HbA1c as well as of rs11190480 with ALT activity, were weak and became non-significant after multiple-testing correction. Also associations of the haplotype harbouring the minor allele of rs1502593 with HbA1c levels, the haplotype harbouring the minor alleles of rs11190480 and rs508384 with activity of ALT, and the haplotype harbouring the minor alleles of rs522951, rs10883463 and rs508384 with triglyceride and HbA1C levels and GGT activities did not withstand multiple-testing correction.

CONCLUSION

These findings suggest that there are no associations between common variants of SCD1 or its inferred haplotypes and the investigated metabolic risk factors. However, given the results from animal models, heterogeneity of human SCD1 warrants further investigation, in particular with regard to rare variants.

Alcohol consumption and risk of type 2 diabetes in European men and women: influence of beverage type and body size The EPIC-InterAct study

OBJECTIVE

To investigate the association between alcohol consumption and type 2 diabetes, and determine whether this is modified by sex, body mass index (BMI) and beverage type.

DESIGN

Multicentre prospective case-cohort study.

SETTING

Eight countries from the European Prospective Investigation into Cancer and Nutrition cohort.

SUBJECTS

A representative baseline sample of 16 154 participants and 12 403 incident cases of type 2 diabetes.

INTERVENTIONS

Alcohol consumption assessed using validated dietary questionnaires.

MAIN OUTCOME MEASURES

Occurrence of type 2 diabetes based on multiple sources (mainly self-reports), verified against medical information.

RESULTS

Amongst men, moderate alcohol consumption was nonsignificantly associated with a lower incidence of diabetes with a hazard ratio (HR) of 0.90 (95% CI: 0.78-1.05) for 6.1-12.0 versus 0.1-6.0 g day(-1) , adjusted for dietary and diabetes risk factors. However, the lowest risk was observed at higher intakes of 24.1-96.0 g day(-1) with an HR of 0.86 (95% CI: 0.75-0.98). Amongst women, moderate alcohol consumption was associated with a lower incidence of diabetes with a hazard ratio of 0.82 (95% CI: 0.72-0.92) for 6.1-12.0 g day(-1) (P interaction gender <0.01). The inverse association between alcohol consumption and diabetes was more pronounced amongst overweight (BMI ≥ 25 kg m(-2) ) than normal-weight men and women (P interaction < 0.05). Adjusting for waist and hip circumference did not alter the results for men, but attenuated the association for women (HR=0.90, 95% CI: 0.79-1.03 for 6.1-12.0 g day(-1) ). Wine consumption for men and fortified wine consumption for women were most strongly associated with a reduced risk of diabetes.

CONCLUSIONS

The results of this study show that moderate alcohol consumption is associated with a lower risk of type 2 diabetes amongst women only. However, this risk reduction is in part explained by fat distribution. The relation between alcohol consumption and type 2 diabetes was stronger for overweight than normal-weight women and men.

Fruit and vegetable intake and type 2 diabetes: EPIC-InterAct prospective study and meta-analysis

Fruit and vegetable intake (FVI) may reduce the risk of type 2 diabetes (T2D), but the epidemiological evidence is inconclusive. The aim of this study is to examine the prospective association of FVI with T2D and conduct an updated meta-analysis. In the European Prospective Investigation into Cancer-InterAct (EPIC-InterAct) prospective case-cohort study nested within eight European countries, a representative sample of 16,154 participants and 12,403 incident cases of T2D were identified from 340,234 individuals with 3.99 million person-years of follow-up. For the meta-analysis we identified prospective studies on FVI and T2D risk by systematic searches of MEDLINE and EMBASE until April 2011. In EPIC-InterAct, estimated FVI by dietary questionnaires varied more than twofold between countries. In adjusted analyses the hazard ratio (95% confidence interval) comparing the highest with lowest quartile of reported intake was 0.90 (0.80-1.01) for FVI; 0.89 (0.76-1.04) for fruit and 0.94 (0.84-1.05) for vegetables. Among FV subtypes, only root vegetables were inversely associated with diabetes 0.87 (0.77-0.99). In meta-analysis using pooled data from five studies including EPIC-InterAct, comparing the highest with lowest category for FVI was associated with a lower relative risk of diabetes (0.93 (0.87-1.00)). Fruit or vegetables separately were not associated with diabetes. Among FV subtypes, only green leafy vegetable (GLV) intake (relative risk: 0.84 (0.74-0.94)) was inversely associated with diabetes. Subtypes of vegetables, such as root vegetables or GLVs may be beneficial for the prevention of diabetes, while total FVI may exert a weaker overall effect.

Reliability of plasma fibroblast growth factor 23 as risk biomarker in epidemiological studies measured over a four-month period

Background

Identified as a biomarker of altered calcium–phosphorus metabolism in chronic kidney disease, fibroblast growth factor 23 (FGF-23) can also be used as a biomarker of risk for cardiovascular disease in the general population. However, it is crucial to first evaluate the reproducibility (reliability) of plasma FGF-23 concentrations.

Methods

We assessed the reliability of plasma FGF-23 concentrations using replicate blood samples taken four months apart of 207 participants from the European Prospective Investigation into Cancer and Nutrition-Potsdam Study.

Results

Plasma FGF-23 concentrations at baseline (geometric mean: 24.7 RU/mL; 95% confidence interval [CI] in RU/mL: 21.8–27.9) were not significantly different from those measured four months later (geometric mean: 23.7 RU/mL; 95% CI in RU/mL: 20.6–27.1; P = 0.42). The intraclass correlation coefficients were 0.69 (95% CI: 0.62–0.76) for all; 0.64 (95% CI: 0.50–0.75) for men and 0.73 (95% CI: 0.64–0.81) for women.

Conclusions

Plasma FGF-23 concentrations showed good reliability over time. Our findings suggest that in epidemiological studies, a single plasma FGF-23 measurement may be sufficient to derive the relative risk in prospective cohort studies.

Low serum glutathione peroxidase activity is associated with increased cardiovascular mortality in individuals with low HDLc's

Background

Since oxidized LDL is thought to initiate atherosclerosis and the serum glutathione peroxidase (GPx3) reduces oxidized lipids, we investigated whether high GPx3 activity reduces cardiovascular disease (CVD) mortality.

Methods

We determined GPx3 in stored samples from the Minnesota Heart Survey of 130 participants who after 5 to 12 years of follow-up had died of CVD and 240 controls. Participants were 26 to 85 years old and predominantly white. In a nested case-control, study we performed logistic regressions to calculate odds ratios (OR) adjusted for age, sex, baseline year, body mass index, smoking, alcohol intake, physical activity, total and HDL cholesterols, systolic blood pressure, serum glucose and gamma glutamyltransferase (GTT) activity. The referent was the quartile with the highest GPx3 activity (quartile 4).

Results

OR’s for CVD mortality for increasing quartiles of GPx3 were 2.37, 2.14, 1.83 and 1.00 (P for trend 0.02). This inverse correlation was confined to those with HDLc’s below the median (P for interaction, 0.006). The OR’s for increasing quartiles of GPx3 in this group were 6.08, 5.00, 3.64 and 1.00 (P for trend, 0.002).

Conclusions

Individuals with both low HDLc and GPx3 activity are at markedly increased risk for death from CVD.

The prospective association between total and type of fish intake and type 2 diabetes in 8 European countries: EPIC-InterAct Study

BACKGROUND

Epidemiologic evidence of an association between fish intake and type 2 diabetes (T2D) is inconsistent and unresolved.

OBJECTIVE

The objective was to examine the association between total and type of fish intake and T2D in 8 European countries.

DESIGN

This was a case-cohort study, nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) study, with 3.99 million person-years of follow-up, 12,403 incident diabetes cases, and a random subcohort of 16,835 individuals from 8 European countries. Habitual fish intake (lean fish, fatty fish, total fish, shellfish, and combined fish and shellfish) was assessed by country-specific dietary questionnaires. HRs were estimated in each country by using Prentice-weighted Cox regression models and pooled by using a random-effects meta-analysis.

RESULTS

No overall association was found between combined fish and shellfish intake and incident T2D per quartile (adjusted HR: 1.00; 95% CI: 0.94, 1.06; P-trend = 0.99). Total fish, lean fish, and shellfish intakes separately were also not associated with T2D, but fatty fish intake was weakly inversely associated with T2D: adjusted HR per quartile 0.97 (0.94, 1.00), with an HR of 0.84 (0.70, 1.01), 0.85 (0.76, 0.95), and 0.87 (0.78, 0.97) for a comparison of the second, third, and fourth quartiles with the lowest quartile of intake, respectively (P-trend = 0.06).

CONCLUSIONS

These findings suggest that lean fish, total fish, and shellfish intakes are not associated with incident diabetes but that fatty fish intake may be weakly inversely associated. Replication of these findings in other populations and investigation of the mechanisms underlying these associations are warranted. Meanwhile, current public health recommendations on fish intake should remain unchanged.

Telomere length, oxidative stress, and antioxidant status in elderly men in Zutphen and Crete

The incidence of chronic diseases such as cardiovascular diseases is lower in Mediterranean Southern Europe than Northern Europe. This may be due to a lower level of oxidative stress and a higher antioxidant status in people living around the Mediterranean Sea. Oxidative stress may influence the rate of shortening of telomeres, the nucleoprotein structures at the ends of chromosomes. We compared leukocyte telomere length (LTL) in elderly men from Northern and Southern Europe and investigated the possible relationship between LTL and indicators of oxidative stress and antioxidant status. We examined 143 elderly Dutch men (mean age 83.9 years) and 109 Greek elderly men (mean age 84.6 years) and found that the Greek men had significantly longer telomeres (geometric mean 4.95 kbp, 95% confidence interval (CI): 4.71-5.23 kbp) compared to the men from the Netherlands (4.76 kbp, 95% CI: 4.55-4.98 kbp; P=0.001). Age was inversely associated with LTL (β=-0.10, P=0.31 in Cretan men and β=-0.19, P=0.02 in Dutch men). In all men LTL was not related to indicators of oxidative stress and plasma antioxidants. However, the endogenous antioxidants serum albumin (β=0.18, P=0.007) and uric acid (β=0.13, P=0.045) were positively associated with LTL. The age-adjusted difference between Crete and Zutphen was reduced by 25% after adjustment for serum albumin and uric acid. We conclude that Greek elderly men have significantly longer LTL compared to Dutch counterparts. The endogenous antioxidants albumin and uric acid were positively associated with longer telomeres.

Variety in vegetable and fruit consumption and the risk of gastric and esophageal cancer in the European Prospective Investigation into Cancer and Nutrition

Diets high in vegetables and fruits have been suggested to be inversely associated with risk of gastric cancer. However, the evidence of the effect of variety of consumption is limited. We therefore investigated whether consumption of a variety of vegetables and fruit is associated with gastric and esophageal cancer in the European Prospective Investigation into Cancer and Nutrition study. Data on food consumption and follow-up on cancer incidence were available for 452,269 participants from 10 European countries. After a mean follow-up of 8.4 years, 475 cases of gastric and esophageal adenocarcinomas (180 noncardia, 185 cardia, gastric esophageal junction and esophagus, 110 not specified) and 98 esophageal squamous cell carcinomas were observed. Diet Diversity Scores were used to quantify the variety in vegetable and fruit consumption. We used multivariable Cox proportional hazard models to calculate risk ratios. Independent from quantity of consumption, variety in the consumption of vegetables and fruit combined and of fruit consumption alone were statistically significantly inversely associated with the risk of esophageal squamous cell carcinoma (continuous hazard ratio per 2 products increment 0.88; 95% CI 0.79-0.97 and 0.76; 95% CI 0.62-0.94, respectively) with the latter particularly seen in ever smokers. Variety in vegetable and/or fruit consumption was not associated with risk of gastric and esophageal adenocarcinomas. Independent from quantity of consumption, more variety in vegetable and fruit consumption combined and in fruit consumption alone may decrease the risk of esophageal squamous cell carcinoma. However, residual confounding by lifestyle factors cannot be excluded.

Fruit and vegetable consumption and prospective weight change in participants of the European Prospective Investigation into Cancer and Nutrition-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home, and Obesity study

BACKGROUND

Fruit and vegetable consumption might prevent weight gain through their low energy density and high dietary fiber content.

OBJECTIVE

We assessed the association between the baseline consumption of fruit and vegetables and weight change in participants from 10 European countries participating in the European Prospective Investigation into Cancer and Nutrition study.

DESIGN

Diet was assessed at baseline in 373,803 participants by using country-specific validated questionnaires. Weight was measured at baseline and self-reported at follow-up in most centers. Associations between baseline fruit and vegetable intakes (per 100 g/d) and weight change (g/y) after a mean follow-up of 5 y were assessed by using linear mixed-models, with age, sex, total energy intake, and other potential confounders controlled for.

RESULTS

After exclusion of subjects with chronic diseases at baseline and subjects who were likely to misreport energy intakes, baseline fruit and vegetable intakes were not associated with weight change overall. However, baseline fruit and vegetable intakes were inversely associated with weight change in men and women who quit smoking during follow-up. We observed weak positive associations between vegetable intake and weight change in women who were overweight, were former smokers, or had high prudent dietary pattern scores and weak inverse associations between fruit intake and weight change in women who were >50 y of age, were of normal weight, were never smokers, or had low prudent dietary pattern scores.

CONCLUSIONS

In this large study, higher baseline fruit and vegetable intakes, while maintaining total energy intakes constant, did not substantially influence midterm weight change overall but could help to reduce risk of weight gain in persons who stop smoking. The interactions observed in women deserve additional attention.

Significant associations of the rs2943634 (2q36.3) genetic polymorphism with adiponectin, high density lipoprotein cholesterol and ischemic stroke

BACKGROUND

rs2943634 C/A single nucleotide polymorphism (SNP), located in a non coding region of chromosome 2q36.3, has been associated with coronary artery disease in two genome wide association studies. Our goal was to investigate its relation with myocardial infarction (MI) and ischemic stroke (IS), as well as with 12 intermediate risk phenotypes, in a population-based prospective cohort study.

METHODS

rs2943634 was genotyped in a case-cohort study including a random sample of 1891 individuals (subcohort) and all incident MI (n=211) and IS (n=144) cases during a mean follow-up of 8.2±2.2years, nested within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort comprising 27,548 middle-aged men and women.

RESULTS

rs2943634 minor allele (A) was associated in an additive fashion with lower risk of IS but not with MI [hazard ratio (HR)=0.66; 95% confidence interval (CI): 0.50-0.87; P=0.003; HR=1.02; 95% CI: 0.82-1.28; P=0.83 respectively, for the age and sex adjusted model]. Furthermore, it was related to slightly higher levels of plasma adiponectin [CC 6.94, CA 7.27, AA 7.86μg/ml, P=0.0002] and high density lipoprotein (HDL)-cholesterol (CC 52.08, CA 53.05 and AA 55.27mg/dl, P=0.002), based on additive models. Adjustment for adiponectin and HDL-cholesterol did not attenuate the association between the SNP and IS risk. In contrast, adjustment for adiponectin abolished the association between the SNP and HDL-cholesterol and adjustment for HDL-cholesterol attenuated the association between the SNP and adiponectin.

CONCLUSIONS

Our findings suggest that rs2943634 is associated with IS risk and with plasma levels of HDL-cholesterol and adiponectin in this German population. Further investigations are needed to confirm these results and to clarify the mechanisms underlying the association.

Design and cohort description of the InterAct Project: an examination of the interaction of genetic and lifestyle factors on the incidence of type 2 diabetes in the EPIC Study

AIMS/HYPOTHESIS

Studying gene-lifestyle interaction may help to identify lifestyle factors that modify genetic susceptibility and uncover genetic loci exerting important subgroup effects. Adequately powered studies with prospective, unbiased, standardised assessment of key behavioural factors for gene-lifestyle studies are lacking. This case-cohort study aims to investigate how genetic and potentially modifiable lifestyle and behavioural factors, particularly diet and physical activity, interact in their influence on the risk of developing type 2 diabetes.

METHODS

Incident cases of type 2 diabetes occurring in European Prospective Investigation into Cancer and Nutrition (EPIC) cohorts between 1991 and 2007 from eight of the ten EPIC countries were ascertained and verified. Prentice-weighted Cox regression and random-effects meta-analyses were used to investigate differences in diabetes incidence by age and sex.

RESULTS

A total of 12,403 verified incident cases of type 2 diabetes occurred during 3.99 million person-years of follow-up of 340,234 EPIC participants eligible for InterAct. We defined a centre-stratified subcohort of 16,154 individuals for comparative analyses. Individuals with incident diabetes who were randomly selected into the subcohort (n = 778) were included as cases in the analyses. All prevalent diabetes cases were excluded from the study. InterAct cases were followed-up for an average of 6.9 years; 49.7% were men. Mean baseline age and age at diagnosis were 55.6 and 62.5 years, mean BMI and waist circumference values were 29.4 kg/m(2) and 102.7 cm in men, and 30.1 kg/m(2) and 92.8 cm in women, respectively. Risk of type 2 diabetes increased linearly with age, with an overall HR of 1.56 (95% CI 1.48-1.64) for a 10 year age difference, adjusted for sex. A male excess in the risk of incident diabetes was consistently observed across all countries, with a pooled HR of 1.51 (95% CI 1.39-1.64), adjusted for age.

CONCLUSIONS/INTERPRETATION

InterAct is a large, well-powered, prospective study that will inform our understanding of the interplay between genes and lifestyle factors on the risk of type 2 diabetes development.

Risk assessment tools for identifying individuals at risk of developing type 2 diabetes

Trials have demonstrated the preventability of type 2 diabetes through lifestyle modifications or drugs in people with impaired glucose tolerance. However, alternative ways of identifying people at risk of developing diabetes are required. Multivariate risk scores have been developed for this purpose. This article examines the evidence for performance of diabetes risk scores in adults by 1) systematically reviewing the literature on available scores and 2) their validation in external populations; and 3) exploring methodological issues surrounding the development, validation, and comparison of risk scores. Risk scores show overall good discriminatory ability in populations for whom they were developed. However, discriminatory performance is more heterogeneous and generally weaker in external populations, which suggests that risk scores may need to be validated within the population in which they are intended to be used. Whether risk scores enable accurate estimation of absolute risk remains unknown; thus, care is needed when using scores to communicate absolute diabetes risk to individuals. Several risk scores predict diabetes risk based on routine noninvasive measures or on data from questionnaires. Biochemical measures, in particular fasting plasma glucose, can improve prediction of such models. On the other hand, usefulness of genetic profiling currently appears limited.

Prediagnostic circulating parathyroid hormone concentration and colorectal cancer in the European Prospective Investigation into Cancer and Nutrition cohort

BACKGROUND

Parathyroid hormone (PTH) has been proposed to play a promoting role in carcinogenesis. However, no epidemiologic studies have yet directly investigated its role in colorectal cancer (CRC).

METHODS

A case-control study nested within the European Prospective Investigation into Cancer and Nutrition cohort was conducted with 1,214 incident, sporadic CRC cases matched to 1,214 controls. Circulating prediagnostic PTH and 25-hydroxy vitamin D [25(OH)D] concentrations were measured by enzyme-linked immunosorbent assays. Detailed dietary and lifestyle questionnaire data were collected at baseline. Multivariable conditional logistic regression was used to estimate the incidence rate ratio (RR) with 95% confidence intervals (95% CI) for the association between circulating PTH and CRC risk.

RESULTS

In multivariate analyses [including adjustment for 25(OH)D concentration] with a priori defined cutoff points, high levels of serum PTH (≥65 ng/L) compared with medium PTH levels of 30-65 ng/L were associated with increased CRC risk (RR = 1.41, 95% CI: 1.03-1.93). In analyses by sex, the CRC risk was 1.77 (95% CI: 1.14-2.75) and 1.15 (95% CI: 0.73-1.84) in men and women, respectively (P(heterogeneity) = 0.01). In subgroup analyses by anatomical subsite, the risk for colon cancer was RR = 1.56, 95% CI: 1.03-2.34, and for rectal cancer RR = 1.20, 95% CI: 0.72-2.01 (P(heterogeneity) = 0.21). Effect modification by various risk factors was examined.

CONCLUSIONS

The results of this study suggest that high serum PTH levels may be associated with incident, sporadic CRC in Western European populations, and in particular among men.

IMPACT

To our knowledge, this is the first study on PTH and CRC. The role of PTH in carcinogenesis needs to be further investigated.

Plasma γ-Glutamyltransferase, Cysteinyl-Glycine, and Oxidized Low-Density Lipoprotein

Objective— To investigate the interrelation between plasma γ-glutamyltransferase (GGT) activity, cysteinyl-glycine (Cys-Gly) (ie, a thiol originating from GGT-mediated cleavage of glutathione), and oxidized low-density lipoprotein (oxLDL) with regard to myocardial infarction (MI) risk in a prospective study.

Methods and Results— Incident cases of MI were identified among European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam participants without prior MI during 6.0 years of follow-up. Baseline levels of Cys-Gly and oxLDL and GGT activity in plasma were measured in a case-cohort study comprising 837 subjects without incident MI and 116 subjects with incident MI. The relation of GGT, Cys-Gly and oxLDL to MI risk was assessed using Cox proportional hazards regression analysis. After adjustment for established risk factors, hazard ratios associated with a 1-SD unit increase in the log-transformed biomarker were 1.63 (95% CI, 1.30 to 2.05) for GGT, 1.36 (95% CI, 1.07 to 1.72) for Cys-Gly, and 1.37 (95% CI, 1.00 to 1.86) for oxLDL. Cys-Gly and oxLDL accounted for 2.3% of the relation between GGT and MI risk.

Conclusion— The positive association between GGT activity and MI risk appears to be independent of circulating Cys-Gly and oxLDL levels. With Cys-Gly, we found a potential new predictor of MI risk whose impact needs to be further elucidated.