Dietary fatty acids and endometrial cancer risk within the European Prospective Investigation into Cancer and Nutrition

BACKGROUND

Diet may impact important risk factors for endometrial cancer such as obesity and inflammation. However, evidence on the role of specific dietary factors is limited. We investigated associations between dietary fatty acids and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS

This analysis includes 1,886 incident endometrial cancer cases and 297,432 non-cases. All participants were followed up for a mean of 8.8 years. Multivariable Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of endometrial cancer across quintiles of individual fatty acids estimated from various food sources quantified through food frequency questionnaires in the entire EPIC cohort. The false discovery rate (q-values) was computed to control for multiple comparisons.

RESULTS

Consumption of n-6 γ-linolenic acid was inversely associated with endometrial cancer risk (HR comparing 5th with 1st quintileQ5-Q1=0.77, 95% CI = 0.64; 0.92, ptrend=0.01, q-value = 0.15). This association was mainly driven by γ-linolenic acid derived from plant sources (HRper unit increment=0.94, 95%CI= (0.90;0.98), p = 0.01) but not from animal sources (HRper unit increment= 1.00, 95%CI = (0.92; 1.07), p = 0.92). In addition, an inverse association was found between consumption of n-3 α-linolenic acid from vegetable sources and endometrial cancer risk (HRper unit increment= 0.93, 95%CI = (0.87; 0.99), p = 0.04). No significant association was found between any other fatty acids (individual or grouped) and endometrial cancer risk.

CONCLUSION

Our results suggest that higher consumption of γ-linolenic acid and α-linoleic acid from plant sources may be associated with lower risk of endometrial cancer.

Adult height, coronary heart disease and stroke: a multi-locus Mendelian randomization meta-analysis

Background: We investigated causal effect of completed growth, measured by adult height, on coronary heart disease (CHD), stroke and cardiovascular traits, using instrumental variable (IV) Mendelian randomization meta-analysis.

Methods: We developed an allele score based on 69 single nucleotide polymorphisms (SNPs) associated with adult height, identified by the IBCCardioChip, and used it for IV analysis against cardiovascular risk factors and events in 21 studies and 60 028 participants. IV analysis on CHD was supplemented by summary data from 180 height-SNPs from the GIANT consortium and their corresponding CHD estimates derived from CARDIoGRAMplusC4D.

Results: IV estimates from IBCCardioChip and GIANT-CARDIoGRAMplusC4D showed that a 6.5-cm increase in height reduced the odds of CHD by 10% [odds ratios 0.90; 95% confidence intervals (CIs): 0.78 to 1.03 and 0.85 to 0.95, respectively],which agrees with the estimate from the Emerging Risk Factors Collaboration (hazard ratio 0.93; 95% CI: 0.91 to 0.94). IV analysis revealed no association with stroke (odds ratio 0.97; 95% CI: 0.79 to 1.19). IV analysis showed that a 6.5-cm increase in height resulted in lower levels of body mass index (P < 0.001), triglycerides (P < 0.001), non high-density (non-HDL) cholesterol (P < 0.001), C-reactive protein (P = 0.042), and systolic blood pressure (P = 0.064) and higher levels of forced expiratory volume in 1 s and forced vital capacity (P < 0.001 for both).

Conclusions: Taller individuals have a lower risk of CHD with potential explanations being that taller people have a better lung function and lower levels of body mass index, cholesterol and blood pressure.

Alcohol consumption and the risk of renal cancers in the European Prospective Investigation into Cancer and Nutrition (EPIC). Wozniak MB, Brennan P, Brenner DR, Overvad K, Olsen A, Tjønneland A, Boutron-Ruault MC, Clavel-Chapelon F, Fagherazzi G, Katzke V, Kühn T, Boeing H, Bergmann MM, Steffen A, Naska A, Trichopoulou A, Trichopoulos D, Saieva C, Grioni S, Panico S, Tumino R, Vineis P, Bueno-de-Mesquita HB, Peeters PH, Hjartåker A, Weiderpass E, Arriola L, Molina-Montes E, Duell EJ, Santiuste C, Alonso de la Torre R, Barricarte Gurrea A, Stocks T, Johansson M, Ljungberg B, Wareham N, Khaw KT, Travis RC, Cross AJ, Murphy N, Riboli E, Scelo G.Int J Cancer. 2015 Oct 15;137(8):1953-66. [Epub 2015 Apr 28]. doi: 10.1002/ijc.29559

Epidemiologic studies have reported that moderate alcohol consumption is inversely associated with the risk of renal cancer. However, there is no information available on the associations in renal cancer subsites. From 1992 to 2010, 477,325 men and women in the European Prospective Investigation into Cancer and Nutrition cohort were followed for incident renal cancers (n = 931). Baseline and lifetime alcohol consumption was assessed by country-specific, validated dietary questionnaires. Information on past alcohol consumption was collected by lifestyle questionnaires. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from Cox proportional hazard models. In multivariate analysis, total alcohol consumption at baseline was inversely associated with renal cancer; the HR and 95% CI for the increasing categories of total alcohol consumption at recruitment vs. the light drinkers category were 0.78 (0.62-0.99), 0.82 (0.64-1.04), 0.70 (0.55-0.90), and 0.91 (0.63-1.30), respectively, (ptrend = 0.001). A similar relationship was observed for average lifetime alcohol consumption and for all renal cancer subsites combined or for renal parenchyma subsite. The trend was not observed in hypertensive individuals and not significant in smokers. In conclusion, moderate alcohol consumption was associated with a decreased risk of renal cancer.

The need for an integrated approach for chronic disease research and care in Africa

With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.

Diabetes and onset of natural menopause: results from the European Prospective Investigation into Cancer and Nutrition

STUDY QUESTION

Do women who have diabetes before menopause have their menopause at an earlier age compared with women without diabetes?

SUMMARY ANSWER

Although there was no overall association between diabetes and age at menopause, our study suggests that early-onset diabetes may accelerate menopause.

WHAT IS KNOWN ALREADY

Today, more women of childbearing age are being diagnosed with diabetes, but little is known about the impact of diabetes on reproductive health.

STUDY DESIGN, SIZE, DURATION

We investigated the impact of diabetes on age at natural menopause (ANM) in 258 898 women from the European Prospective Investigation into Cancer and Nutrition (EPIC), enrolled between 1992 and 2000.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Determinant and outcome information was obtained through questionnaires. Time-dependent Cox regression analyses were used to estimate the associations of diabetes and age at diabetes diagnosis with ANM, stratified by center and adjusted for age, smoking, reproductive and diabetes risk factors and with age from birth to menopause or censoring as the underlying time scale.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, no association between diabetes and ANM was found (hazard ratio (HR) = 0.94; 95% confidence interval (CI) 0.89-1.01). However, women with diabetes before the age of 20 years had an earlier menopause (10-20 years: HR = 1.43; 95% CI 1.02-2.01, <10 years: HR = 1.59; 95% CI 1.03-2.43) compared with non-diabetic women, whereas women with diabetes at age 50 years and older had a later menopause (HR = 0.81; 95% CI 0.70-0.95). None of the other age groups were associated with ANM.

LIMITATIONS, REASONS FOR CAUTION

Strengths of the study include the large sample size and the broad set of potential confounders measured. However, results may have been underestimated due to survival bias. We cannot be sure about the sequence of the events in women with a late age at diabetes, as both events then occur in a short period. We could not distinguish between type 1 and type 2 diabetes.

WIDER IMPLICATIONS OF THE FINDINGS

Based on the literature, an accelerating effect of early-onset diabetes on ANM might be plausible. A delaying effect of late-onset diabetes on ANM has not been reported before, and is not in agreement with recent studies suggesting the opposite association.

STUDY FUNDING/COMPETING INTERESTS

The coordination of EPIC is financially supported by the European Commission (DG-SANCO) and the International Agency for Research on Cancer. The national cohorts are supported by Danish Cancer Society (Denmark); Ligue Contre le Cancer, Institut Gustave Roussy, Mutuelle Générale de l'Education Nationale, Institut National de la Santé et de la Recherche Médicale (INSERM) (France); German Cancer Aid, German Cancer Research Center (DKFZ) and Federal Ministry of Education and Research (BMMF) (Germany); Ministry of Health and Social Solidarity, Stavros Niarchos Foundation and Hellenic Health Foundation (Greece); Italian Association for Research on Cancer (AIRC) and National Research Council (Italy); Dutch Ministry of Public Health, Welfare and Sports (VWS), Netherlands Cancer Registry (NKR), LK Research Funds, Dutch Prevention Funds, Dutch ZON (Zorg Onderzoek Nederland), World Cancer Research Fund (WCRF), Statistics Netherlands (The Netherlands); ERC-2009-AdG 232997 and Nordforsk, Nordic Centre of Excellence programme on Food, Nutrition and Health (Norway); Health Research Fund (FIS), Regional Governments of Andalucía, Asturias, Basque Country, Murcia (no. 6236) and Navarra, ISCIII RETIC (RD06/0020) (Spain); Swedish Cancer Society, Swedish Scientific Council and Regional Government of Skåne and Västerbotten (Sweden); Cancer Research UK, Medical Research Council, Stroke Association, British Heart Foundation, Department of Health, Food Standards Agency, and Wellcome Trust (UK). None of the authors reported a conflict of interest.

Fruit and vegetable consumption in relation to hepatocellular carcinoma in a multi-centre, European cohort study

BACKGROUND

Vegetable and/or fruit intakes in association with hepatocellular carcinoma (HCC) risk have been investigated in case-control studies conducted in specific European countries and cohort studies conducted in Asia, with inconclusive results. No multi-centre European cohort has investigated the indicated associations.

METHODS

In 486,799 men/women from the European Prospective Investigation into Cancer and nutrition, we identified 201 HCC cases after 11 years median follow-up. We calculated adjusted hazard ratios (HRs) for HCC incidence for sex-specific quintiles and per 100 g d(-1) increments of vegetable/fruit intakes.

RESULTS

Higher vegetable intake was associated with a statistically significant, monotonic reduction of HCC risk: HR (100 g d(-1) increment): 0.83; 95% CI: 0.71-0.98. This association was consistent in sensitivity analyses with no apparent heterogeneity across strata of HCC risk factors. Fruit intake was not associated with HCC incidence: HR (100 g d(-1) increment): 1.01; 95% CI: 0.92-1.11.

CONCLUSIONS

Vegetable, but not fruit, intake is associated with lower HCC risk with no evidence for heterogeneity of this association in strata of important HCC risk factors. Mechanistic studies should clarify pathways underlying this association. Given that HCC prognosis is poor and that vegetables are practically universally accessible, our results may be important, especially for those at high risk for the disease.

BMI is an important driver of β-cell loss in type 1 diabetes upon diagnosis in 10 to 18-year-old children

OBJECTIVE

Body weight-related insulin resistance probably plays a role in progression to type 1 diabetes, but has an uncertain impact following diagnosis. In this study, we investigated whether BMI measured at diagnosis was an independent predictor of C-peptide decline 1-year post-diagnosis.

DESIGN

Multicentre longitudinal study carried out at diagnosis and up to 1-year follow-up.

METHODS

Data on C-peptide were collected from seven diabetes centres in Europe. Patients were grouped according to age at diagnosis (<5 years, n=126; >5 years <10 years, n=295; >10 years <18 years, n=421; >18 years, n=410). Linear regression was used to investigate whether BMI was an independent predictor of change in fasting C-peptide over 1 year. Models were additionally adjusted for baseline insulin dose and HbA1c.

RESULTS

In individuals diagnosed between 0 and 5 years, 5 and 10 years and those diagnosed >18 years, we found no association between BMI and C-peptide decline. In patients aged 10-18 years, higher BMI at baseline was associated with a greater decline in fasting C-peptide over 1 year with a decrease (β 95% CI; P value) of 0.025 (0.010, 0.041) nM/kg per m(2) higher baseline BMI (P=0.001). This association remained significant after adjusting for gender and differences in HbA1c and insulin dose (β=0.026, 95% CI=0.0097, 0.042; P=0.002).

CONCLUSIONS

These observations indicate that increased body weight and increased insulin demand are associated with more rapid disease progression after diagnosis of type 1 diabetes in an age group 10-18 years. This should be considered in studies of β-cell function in type 1 diabetes.

Dietary intake of acrylamide and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition cohort

BACKGROUND

Three prospective studies have evaluated the association between dietary acrylamide intake and endometrial cancer (EC) risk with inconsistent results. The objective of this study was to evaluate the association between acrylamide intake and EC risk: for overall EC, for type-I EC, and in never smokers and never users of oral contraceptives (OCs). Smoking is a source of acrylamide, and OC use is a protective factor for EC risk.

METHODS

Cox regression was used to estimate hazard ratios (HRs) for the association between acrylamide intake and EC risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Acrylamide intake was estimated from the EU acrylamide monitoring database, which was matched with EPIC questionnaire-based food consumption data. Acrylamide intake was energy adjusted using the residual method.

RESULTS

No associations were observed between acrylamide intake and overall EC (n=1382) or type-I EC risk (n=627). We observed increasing relative risks for type-I EC with increasing acrylamide intake among women who both never smoked and were non-users of OCs (HRQ5vsQ1: 1.97, 95% CI: 1.08-3.62; likelihood ratio test (LRT) P-value: 0.01, n=203).

CONCLUSIONS

Dietary intake of acrylamide was not associated with overall or type-I EC risk; however, positive associations with type I were observed in women who were both non-users of OCs and never smokers.

Plasma methionine, choline, betaine, and dimethylglycine in relation to colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC)

BACKGROUND

Disturbances in one carbon metabolism may contribute to carcinogenesis by affecting methylation and synthesis of DNA. Choline and its oxidation product betaine are involved in this metabolism and can serve as alternative methyl group donors when folate status is low.

PATIENTS AND METHODS

We conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), to investigate plasma concentrations of the methyl donors methionine, choline, betaine (trimethylglycine), and dimethylglycine (DMG) in relation to colorectal cancer (CRC) risk. Our study included 1367 incident CRC cases (965 colon and 402 rectum) and 2323 controls matched by gender, age group, and study center. Multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for CRC risk were estimated by conditional logistic regression, comparing the fifth to the first quintile of plasma concentrations.

RESULTS

Overall, methionine (OR: 0.79, 95% CI: 0.63-0.99, P-trend = 0.05), choline (OR: 0.77, 95% CI: 0.60-0.99, P-trend = 0.07), and betaine (OR: 0.85, 95% CI: 0.66-1.09, P-trend = 0.06) concentrations were inversely associated with CRC risk of borderline significance. In participants with folate concentration below the median of 11.3 nmol/l, high betaine concentration was associated with reduced CRC risk (OR: 0.71, 95% CI: 0.50-1.00, P-trend = 0.02), which was not observed for those having a higher folate status. Among women, but not men, high choline concentration was associated with decreased CRC risk (OR: 0.62, 95% CI: 0.43-0.88, P-trend = 0.01). Plasma DMG was not associated with CRC risk.

CONCLUSIONS

Individuals with high plasma concentrations of methionine, choline, and betaine may be at reduced risk of CRC.

Adherence to the Mediterranean diet and risk of bladder cancer in the EPIC cohort study

There is growing evidence of the protective role of the Mediterranean diet (MD) on cancer. However, to date no epidemiological study has investigated the influence of the MD on bladder cancer. We evaluated the association between adherence to the MD and risk of urothelial cell bladder cancer (UCC), according to tumor aggressiveness, in the European Prospective Investigation into Cancer and Nutrition (EPIC). The analysis included 477,312 participants, recruited from ten European countries between 1991 and 2000. Information from validated dietary questionnaires was used to develop a relative Mediterranean diet score (rMED), including nine dietary components. Cox regression models were used to assess the effect of the rMED on UCC risk, while adjusting for dietary energy and tobacco smoking of any kind. Stratified analyses were performed by sex, BMI, smoking status, European region and age at diagnosis. During an average follow-up of 11 years, 1,425 participants (70.9% male) were diagnosed with a first primary UCC. There was a negative but non-significant association between a high versus low rMED score and risk of UCC overall (HR: 0.84 [95% CI 0.69, 1.03]) and risk of aggressive (HR: 0.88 [95% CI 0.61, 1.28]) and non-aggressive tumors (HR: 0.78 [95% CI 0.54, 1.14]). Although there was no effect modification in the stratified analyses, there was a significant 34% (p = 0.043) decreased risk of UCC in current smokers with a high rMED score. In EPIC, the MD was not significantly associated with risk of UCC, although we cannot exclude that a MD may reduce risk in current smokers.

Age-dependent decline of β-cell function in type 1 diabetes after diagnosis: a multi-centre longitudinal study

AIMS

C-peptide secretion is currently the only available clinical biomarker to measure residual β-cell function in type 1 diabetes. However, the natural history of C-peptide decline after diagnosis can vary considerably dependent upon several variables. We investigated the shape of C-peptide decline over time from type 1 diabetes onset in relation to age at diagnosis, haemoglobin A1c (HbA1c) levels and insulin dose.

METHODS

We analysed data from 3929 type 1 diabetes patients recruited from seven European centres representing all age groups at disease onset (childhood, adolescence and adulthood). The influence of the age at onset on β-cell function was investigated in a longitudinal analysis at diagnosis and up to 5-years follow-up.

RESULTS

Fasting C-peptide (FCP) data at diagnosis were available in 3668 patients stratified according to age at diagnosis in four groups (<5 years, n = 344; >5 years < 10 years, n = 668; >10 years < 18 years, n = 991; >18 years, n = 1655). FCP levels were positively correlated with age (p < 0.001); the subsequent decline in FCP over time was log-linear with a greater decline rate in younger age groups (p < 0.0001).

CONCLUSIONS

This study reveals a positive correlation between age at diagnosis of type 1 diabetes and FCP with a more rapid decline of β-cell function in the very young patients. These data can inform the design of clinical trials using C-peptide values as an end-point for the effect of a given treatment.

Physical activity, sex steroid, and growth factor concentrations in pre- and post-menopausal women: a cross-sectional study within the EPIC cohort

PURPOSE

Increased physical activity (PA) is associated with a reduced risk of several cancers. PA may reduce cancer risk by changing endogenous hormones levels, but relatively little research has focused on this topic. The purpose of this study was to elucidate the relation between PA and endogenous hormone concentrations.

METHODS

A cross-sectional analysis of 798 pre- and 1,360 post-menopausal women included as controls in case-control studies on endogenous hormones (steroids, progesterone, sex-hormone-binding globulin (SHBG), and growth factors) levels, and cancer risk nested within European Prospective Investigation into Cancer and Nutrition cohort was performed. Multivariate regression analyses were performed to compare geometric mean levels of hormones and SHBG by categories of PA.

RESULTS

In pre-menopausal women, active women had 19 % significantly lower concentrations of androstenedione, 14 % lower testosterone, and 20 % lower free testosterone than inactive women, while no differences were observed for estrogens, progesterone, SHBG, and growth factors. In post-menopausal women, active women had 18 % significantly lower estradiol and 20 % lower free estradiol concentrations than inactive women, while no differences were observed for the other hormones and SHBG. More vigorous forms of physical activity were associated with higher insulin-like growth factor-I concentrations. Adjustment for body mass index did not alter the associations. Overall, the percentage of variance in hormone concentrations explained by PA levels was <2 %.

CONCLUSIONS

Our results support the hypothesis of an influence, although small in magnitude, of PA on sex hormone levels in blood, independent of body size.

Diabetes mellitus, insulin treatment, diabetes duration, and risk of biliary tract cancer and hepatocellular carcinoma in a European cohort

BACKGROUND

Evidence on associations between self-reported diabetes mellitus, diabetes duration, age at diabetes diagnosis, insulin treatment, and risk of biliary tract cancer (BTC) and hepatocellular carcinoma (HCC), independent of general and abdominal obesity is scarce.

PATIENTS AND METHODS

We conducted a prospective analysis in the EPIC-cohort study among 363 426 participants with self-reported diabetes data. Multivariable adjusted relative risks and 95% confidence intervals were estimated from Cox regression models. In a nested case-control subset, analyses were carried out in HCV/HBV-negative individuals.

RESULTS

During 8.5 years of follow-up, 204 BTC cases [including 75 gallbladder cancer (GBC) cases], and 176 HCC cases were identified. Independent of body mass index and waist-to-height ratio diabetes status was associated with higher risk of BTC and HCC [1.77 (1.00-3.13) and 2.17 (1.36-3.47)]. For BTC, the risk seemed to be higher in participants with shorter diabetes duration and those not treated with insulin. Regarding cancer subsites, diabetes was only associated with GBC [2.72 (1.17-6.31)]. The risk for HCC was particularly higher in participants treated with insulin. The results were not appreciably different in HCV/HBV-negative individuals.

CONCLUSION(S)

This study supports the hypothesis that diabetes is a risk factor for BTC (particularly GBC) and HCC. Further research is required to establish whether diabetes treatment or duration is associated with these cancers.

Helicobacter pylori infection assessed by ELISA and by immunoblot and noncardia gastric cancer risk in a prospective study: the Eurgast-EPIC project

BACKGROUND

In epidemiological studies, Helicobacter pylori infection is usually detected by enzyme-linked immunosorbent assay (ELISA). However, infection can spontaneously clear from the mucosa during the progression of atrophy and could lead to substantial under-detection of infection and underestimation of its effect on gastric cancer (GC) risk. Antibodies detected by western blot are known to persist longer after the loss of the infection.

METHODS

In a nested case-control study from the Eurogast-EPIC cohort, including 88 noncardia GC cases and 338 controls, we assessed the association between noncardia GC and H. pylori infection comparing antibodies detected by western blot (HELICOBLOT2.1) to those detected by ELISA (Pyloriset EIA-GIII(®)).

RESULTS

By immunoblot, 82 cases (93.2%) were H. pylori positive, 10 of these cases (11.4%) were negative by ELISA and only 6 cases (6.8%) were negative by both ELISA and immunoblot. Multivariable odds ratio (OR) for noncardia GC comparing immunoglobulin G positive versus negative by ELISA was 6.8 [95% confidence interval (CI) 3.0-15.1], and by immunoblot, the OR was 21.4 (95% CI 7.1-64.4).

CONCLUSIONS

Using a western blot assay, nearly all noncardia GC were classified as H. pylori positive and the OR was more than threefold higher than the OR assessed by ELISA, supporting the hypothesis that H. pylori infection is a necessary condition for noncardia GC.

Inflammation marker and risk of pancreatic cancer: a nested case-control study within the EPIC cohort

Background:

Established risk factors for pancreatic cancer include smoking, long-standing diabetes, high body fatness, and chronic pancreatitis, all of which can be characterised by aspects of inflammatory processes. However, prospective studies investigating the relation between inflammatory markers and pancreatic cancer risk are scarce.

Methods:

We conducted a nested case–control study within the European Prospective Investigation into Cancer and Nutrition, measuring prediagnostic blood levels of C-reactive protein (CRP), interleukin-6 (IL-6), and soluble receptors of tumour necrosis factor-α (sTNF-R1, R2) in 455 pancreatic cancer cases and 455 matched controls. Odds ratios (ORs) were estimated using conditional logistic regression models.

Results:

None of the inflammatory markers were significantly associated with risk of pancreatic cancer overall, although a borderline significant association was observed for higher circulating sTNF-R2 (crude OR=1.52 (95% confidence interval (CI) 0.97–2.39), highest vs lowest quartile). In women, however, higher sTNF-R1 levels were significantly associated with risk of pancreatic cancer (crude OR=1.97 (95% CI 1.02–3.79)). For sTNF-R2, risk associations seemed to be stronger for diabetic individuals and those with a higher BMI.

Conclusion:

Prospectively, CRP and IL-6 do not seem to have a role in our study with respect to risk of pancreatic cancer, whereas sTNF-R1 seemed to be a risk factor in women and sTNF-R2 might be a mediator in the risk relationship between overweight and diabetes with pancreatic cancer. Further large prospective studies are needed to clarify the role of proinflammatory proteins and cytokines in the pathogenesis of exocrine pancreatic cancer.

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.

Intensive multifactorial intervention improves modelled coronary heart disease risk in screen-detected Type 2 diabetes mellitus: a cluster randomized controlled trial

AIMS

To compare the effects of intensive multifactorial cardiovascular risk intervention with standard care in screen-detected Type 2 diabetes.

METHODS

Twenty general practices randomly invited 30 950 adults without diagnosed diabetes for screening (World Health Organization, 1999). In a cluster randomized controlled trial, screen-detected cases were assigned by practice allocation to receive intensive protocol-driven cardiovascular risk management (n = 146) or standard care (n = 199) according to local guidelines. Intensive intervention was designed to achieve an HbA(1c) of 48 mmol/mol (6.5%), blood pressure < 130/80 mmHg and total cholesterol < 3.5 mmol/l. Primary outcome was modelled 5-year coronary heart disease risk (UKPDS-CHD). Analysis was via intention to treat.

RESULTS

After 1.1 years 339 (98%) individuals were still participating. There were significant reductions in HbA(1c) , blood pressure and total cholesterol from baseline in both groups [mean change for total study population -27.7 mmol/mol (-0.62%), -11.64/10.01 mmHg, -1.11 mmol/l]. After adjustment for baseline and clustering, significant inter-group differences were observed in mean changes from baseline for HbA(1c) {-28.5 mmol/mol [-0.7% (1.4)] vs. -27.5 mmol/mol [-0.6% (1.6)], P = 0.001}, blood pressure [systolic -16.2 (19.6) vs. -8.4 (18.6) mmHg, P < 0.001], total cholesterol [-1.3 (1.3) vs. -1.0 (1.2) mmol/l, P < 0.001] and weight [-3.8 (5.5) vs. -2.2 (5.5) kg, P = 0.01] in favour of intensive treatment. UKPDS 5-year coronary heart disease risk was reduced by 3.2% and 2.3%, respectively (P < 0.0001). Intensive intervention was associated with more lipid-lowering and anti-hypertensive but not hypoglycaemic medication use [odds ratios 2.5 (1.4-4.4), 5.5 (2.4-11.5), 1.6 (0.8-2.3); compared with standard care, P < 0.001, P = 0.003, P = 0.65]. Treatment satisfaction responses were superior with intensive intervention, with no increase in self-reported hypoglycaemia.

CONCLUSION

Intensive intervention in patients with diabetes identified through systematic non-risk-factor-based screening significantly reduces modelled coronary heart disease risk. This is achieved predominantly with lipid-lowering and anti-hypertensive treatments with no adverse effect on quality of life or hypoglycaemia.

Physical activity, calcium intake and childhood bone mineral: a population-based cross-sectional study

In a free-living cohort of 4-year old children, mean daily time in moderate-vigorous physical activity and daily calcium intake at 3 years, were positively related to hip bone size and density. Relationships between physical activity and bone indices were stronger when calcium intake was above compared with below median (966 mg/day).

INTRODUCTION

We examined the cross-sectional relationships between childhood physical activity, dietary calcium intake and bone size and density.

METHODS

Children aged 4 years were recruited from the Southampton Women's Survey. They underwent measurement of bone mass by DXA (Hologic Discovery). Physical activity was assessed by accelerometry (Actiheart, Cambridge Neurotechnology Ltd, Cambridge, UK) for seven continuous days.

RESULTS

Four hundred twenty-two children (212 boys) participated. In a cross-sectional analysis, after adjusting for gender, daily mean time(minutes per day) spent in moderate to very vigorous activity (MVPA) was positively related to hip BA (R(2) = 3%, p < 0.001), BMC (R(2) = 4%, p < 0.001), aBMD (R (2) = 3%, p = 0.001) and estimated vBMD (R(2) = 2%, p = 0.01), but not height (r (s) = 0.04, p = 0.42) or weight (r(s) = 0.01, p = 0.76). Mean daily calcium intake (assessed at 3 years old) positively predicted bone indices in those with a calcium intake below the median (966 mg/day), but there was a much attenuated relationship in those above this. These associations persisted after inclusion of total energy, protein and phosphorus in multivariate models. The relationships between MVPA and bone indices were stronger in children with calcium intakes above the median. Thus, for aBMD, the variance explained by MVPA when daily calcium intake was below the median was 2% (p = 0.1) and above median was 6% (p = 0.001).

CONCLUSIONS

These results support the notion that adequate calcium intake may be required for optimal action of physical activity on bone development and that improving levels of physical activity and calcium intake in childhood may help to optimise accrual of bone mass.

Diabetes mellitus, glycated haemoglobin and C-peptide levels in relation to pancreatic cancer risk: a study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

AIMS/HYPOTHESIS

There has been long-standing debate about whether diabetes is a causal risk factor for pancreatic cancer or a consequence of tumour development. Prospective epidemiological studies have shown variable relationships between pancreatic cancer risk and blood markers of glucose and insulin metabolism, overall and as a function of lag times between marker measurements (blood donation) and date of tumour diagnosis.

METHODS

Pre-diagnostic levels of HbA(1c) and C-peptide were measured for 466 participants with pancreatic cancer and 466 individually matched controls within the European Prospective Investigation into Cancer and Nutrition. Conditional logistic regression models were used to estimate ORs for pancreatic cancer.

RESULTS

Pancreatic cancer risk gradually increased with increasing pre-diagnostic HbA(1c) levels up to an OR of 2.42 (95% CI 1.33, 4.39 highest [≥ 6.5%, 48 mmol/mol] vs lowest [≤ 5.4%, 36 mmol/mol] category), even for individuals with HbA(1c) levels within the non-diabetic range. C-peptide levels showed no significant relationship with pancreatic cancer risk, irrespective of fasting status. Analyses showed no clear trends towards increasing hyperglycaemia (as marked by HbA(1c) levels) or reduced pancreatic beta cell responsiveness (as marked by C-peptide levels) with decreasing time intervals from blood donation to cancer diagnosis.

CONCLUSIONS/INTERPRETATION

Our data on HbA(1c) show that individuals who develop exocrine pancreatic cancer tend to have moderate increases in HbA(1c) levels, relatively independently of obesity and insulin resistance-the classic and major risk factors for type 2 diabetes. While there is no strong difference by lag time, more data are needed on this in order to reach a firm conclusion.

Self-rated health does not explain the socioeconomic differential in mortality: a prospective study in the EPIC-Norfolk cohort

BACKGROUND

Self-rated health (SRH), a subjective measure of health, is strongly predictive of mortality, independently of objective measures of health status and existing known disease. There is a strong social gradient in SRH. An investigation was carried to determine whether SRH can explain the well-known socioeconomic gradient in mortality.

METHODS

The effect of adjusting for SRH on the socioeconomic differential in mortality was examined in a prospective study of 20 754 men and women aged 39-79 years, without prevalent disease, living in the general community in Norfolk, UK, recruited using general practice age-sex registers for 1993-1997 and followed up for an average of 10 years.

RESULTS

Mortality risk increased with decreasing social class in men and women. There was some attenuation after adjustment for covariates age, body mass index, smoking, history of diabetes, systolic blood pressure, cholesterol level, alcohol consumption, physical activity and educational level, but a gradient remained. Further adjustment for SRH attenuated the association slightly more, but there was still some evidence of a socioeconomic differential in mortality, particularly in class V compared with class I (age- and sex-adjusted hazard ratio 1.57; 95% CI 1.19 to 2.06).

CONCLUSIONS

SRH does not substantially explain the socioeconomic differential in mortality beyond that explained by health-related covariates.

Association between age at menarche and risk of diabetes in adults: results from the EPIC-Norfolk cohort study

AIMS/HYPOTHESIS

Earlier age at menarche is associated with increased BMI and obesity risk from early childhood through to adulthood. We hypothesised that earlier age at menarche would also predict subsequent diabetes risk.

METHODS

This was a population-based prospective cohort study of 13,308 women, who were aged 40 to 75 years between 1993 and 1997 and participating in the Norfolk cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Norfolk). We used data on age at menarche and ascertained diabetes incidence to 2005.

RESULTS

There were 734 cases of diabetes (363 incident and 371 prevalent cases). Mean age at menarche was lower in women with diabetes than in non-diabetic women (12.8 vs 13.0 years, p = 0.008). Compared with the earliest quintile (menarche at 8-11 years), women in the oldest quintile (menarche at 15-18 years) had lower BMI (25.5 vs 27.4 kg/m2, p < 0.0001) and a reduced risk of diabetes (OR 0.66 [95% CI 0.51-0.86] adjusted for age, family history, physical activity, smoking, occupational social class, parity and use of hormonal preparations). The association between age at menarche and diabetes was linear (adjusted OR 0.91 [95% CI 0.87-0.96] per 1 year later menarche) and appeared to be completely mediated by adult BMI or waist circumference (OR 0.98 [95% CI 0.93-1.03], further adjusted for BMI at age 40-75 years).

CONCLUSIONS/INTERPRETATION

Earlier age at menarche increases the risk of diabetes in women and this association appears to be mediated by increased adiposity. History of earlier menarche may help to identify women with increased subsequent risk of diabetes.

Differential effects of fatness, fitness and physical activity energy expenditure on whole-body, liver and fat insulin sensitivity

AIMS/HYPOTHESIS

The relative contributions of fitness (maximal oxygen uptake), physical activity energy expenditure (PAEE) and fatness to whole-body, liver and fat insulin sensitivity is uncertain. The aim of this study was to determine whether fitness and PAEE are associated with whole-body, liver and fat insulin sensitivity independently of body fat.

MATERIALS AND METHODS

We recruited 25 men (mean [SD] age 53 [6] years). Whole-body (M value) and liver (percentage suppression of endogenous glucose output) insulin sensitivity were estimated using a hyperinsulinaemic-euglycaemic clamp. Insulin sensitivity in fat (insulin sensitivity index for NEFA) was estimated during an OGTT. Total and truncal fat were measured by dual-energy X-ray absorptiometry, fitness by treadmill, and PAEE (n = 21) by 3 day heart rate monitoring and Baecke questionnaire.

RESULTS

In univariate analyses, fatness was strongly associated with insulin sensitivity (whole-body, liver and fat). Fitness was associated with whole-body (r = 0.53, p < 0.007) and liver (0.42, p = 0.04) insulin sensitivity, while PAEE was associated with liver insulin sensitivity (r = 0.55, p = 0.01). Regression models were established to describe associations between fatness, fitness and physical activity and measures of insulin sensitivity (whole-body, fat and liver) as outcomes. Only fatness was independently associated with whole-body insulin sensitivity (B coefficient -0.01, p = 0.001). Fitness was not associated with any outcome. Only PAEE was independently associated with liver insulin sensitivity (B coefficient 13.5, p = 0.02).

CONCLUSIONS/INTERPRETATION

Fatness explains most of the variance in whole-body insulin sensitivity. In contrast, PAEE explains most of the variance in liver insulin sensitivity.

Effects of physical activity on evolution of proximal femur structure in a younger elderly population

INTRODUCTION

For a fixed weight, a wider bone of standardised length is stiffer. But moving the cortices away from the centre of mass risks creating structural (elastic) instability, and hip fractures have been postulated to occur as a consequence of buckling of the thinned supero-lateral femoral neck cortex during a fall. We hypothesised that stereotyped physical activity (e.g., walking) may help conserve bending resistance (section modulus, Z) through redistribution of bone tissue, but it might be at the expense of supero-lateral cortical stability.

METHODS

Hip structural analysis (HSA) software applied to DXA scans was used to derive measurements of section modulus and distances of a cross-section's centre of mass from the supero-lateral cortical margin (lateral distance, in cm). DXA scans were obtained on 1361 men and women in the EPIC-Norfolk population-based prospective cohort study. Up to 4 repeat DXA scans were done in 8 years of follow-up. Weight, height and activities of daily living were assessed on each occasion. A detailed physical activity and lifestyle questionnaire was administered at baseline. The lateral distance was measured on three narrow cross-sections with good precision: narrow neck (NN, coefficient of variation 2.6%), intertrochanter (IT) and shaft (S). A linear mixed model was used to assess associations with predictors.

RESULTS

Ageing was associated with medial shifting of the centre of mass, so that lateral distance increased. Both greater weight and height were associated with greater lateral distance (P<0.0001). Among physical activity-related variables, walking/cycling for >1 h/day (P=0.025), weekly time spent on moderate impact activity (P=0.003), forced expiratory volume in 1 s (NN and IT, P<0.026) and lifetime physical activity (IT, P<0.0001) were associated with higher lateral distance. However, after adjusting for these variables, activities of daily living scores (NN, P<0.0001) and weekly time spent on low impact hip flexing activities were associated with shorter lateral distance (P=0.001). Greater baseline lateral distance was significantly associated with increased risk of subsequent hip fracture (n=26) in females (P<0.05, all regions) independently of age, height and bone mineral content.

CONCLUSION

The age-related shift medially of the centre of mass of the femoral neck and trochanter may have adverse effects on fracture resistance in the event of a fall, so compromising the beneficial effects of walking on fitness, strength and risk of falling. The role of more diverse physical activity patterns in old age that impose loading on the supero-lateral cortex of the femur, involving for example hip flexion and stretching, needs investigation for their ability to correct this medial shifting of the centre of mass.

Area deprivation predicts lung function independently of education and social class

The cross-sectional association between socioeconomic status (at both the individual and area-based level) and lung function, as measured by forced expiratory volume in one second, in a large population-based cohort was investigated. The study population consisted of 22,675 males and females aged 39-79 yrs. They were recruited from the general community in Norfolk, UK using general practice age/sex registers, as part of the European Prospective Investigation into Cancer (EPIC-Norfolk). It was found that being in a manual occupational social class, having no educational qualifications and living in a deprived area all independently predicted significantly lower lung function, even after controlling for smoking habit. The influence of area-deprivation on lung function, independent of individual socioeconomic status and of individual smoking habit, suggests that apart from targeting individuals who are at high-risk, such as smokers, environmental determinants also need to be examined when considering measures to improve respiratory health.

Abdominal obesity and respiratory function in men and women in the EPIC-Norfolk Study, United Kingdom

Poor respiratory function and obesity are associated with all-cause and cardiovascular disease mortality. Obese persons may also have impaired lung function, but the mechanism is unclear. The authors investigated the relation between abdominal pattern of obesity and respiratory function in the European Prospective Investigation into Cancer and Nutrition-Norfolk (EPIC-Norfolk) cohort in Norfolk, United Kingdom. This analysis included 9,674 men and 11,876 women aged 45-79 years with no known preexisting serious illness who had complete anthropometric and respiratory function measures obtained at a health visit between 1993 and 1997. Waist:hip ratio was used to assess abdominal obesity, and forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC), obtained by spirometry, were used to assess respiratory function. Both FEV1 and FVC were linearly and inversely related across the entire range of waist:hip ratio in both men and women. This relation persisted after adjustment for age, body mass index, cigarette smoking, social class, physical activity index, prevalent bronchitis/emphysema, and prevalent asthma. The association remained significant among nonobese nonsmokers without preexisting respiratory disease. In the general adult population, abdominal fat deposition may play a role in the impairment of respiratory function among the abdominally obese.

Occupational social class, educational level and area deprivation independently predict plasma ascorbic acid concentration: a cross-sectional population based study in the Norfolk cohort of the European Prospective Investigation into Cancer (EPIC-Norfolk)

OBJECTIVE

To investigate the independent association between three different measures of socioeconomic status and plasma ascorbic acid level.

DESIGN

Cross-sectional population based study.

SETTING AND PARTICIPANTS

20 292 men and women aged 39-79 y who participated in the EPIC-Norfolk study.

RESULTS

Individuals in manual social classes, who had no educational qualifications or those who lived in the most deprived areas had significantly lower levels of plasma ascorbic acid compared to those in nonmanual social classes, with at least O-level qualifications or who lived in less deprived areas. The magnitude of effect for each measure of socioeconomic status was greater in current smokers compared to current nonsmokers.

CONCLUSION

Education and social class were stronger predictors of differences in ascorbic acid levels, an indicator of dietary health behaviour, than a deprivation index based on the Townsend score. This suggests that education could be particularly important in influencing large socioeconomic differentials in health related behaviours and potentially, health outcomes in the UK.

Hip section modulus, a measure of bending resistance, is more strongly related to reported physical activity than BMD

We hypothesized that measures of physical activity would have a closer relationship with section modulus (SM), an indicator of bending resistance, than with bone mineral density (BMD) because physical activity might expand the bony envelope, which tends to reduce BMD for a constant bone mineral content. Four hundred twenty-three men and 436 women (mean age 72 years, SD =3) were recruited from a prospective population-based cohort study to a study of hip bone loss. Hip BMD was measured on two occasions 2-5 years apart (mean 2.7, DXA-Hologic 1,000 W). Hip structural analysis (HSA) software was used to calculate SM and BMD from the DXA scans on three narrow regions: the narrow neck (NN), intertrochanter (IT) and shaft (S). A physical activity and lifestyle questionnaire was administered at baseline. Multivariate repeated measures analysis of variance was used to model the associations between personal attributes (weight, height, age), physical activity and lifestyle variables with SM, cross-sectional area (CSA), sub-periosteal diameter (PD) and BMD. Men and women were analysed together after tests for interactions with gender, which were found not to be significant. In all regions female gender was associated with having lower values of all outcomes, and body weight was positively associated with all outcomes, i.e., SM, CSA, PD and BMD ( P<0.0001). Sub-periosteal diameter was positively associated with reported lifetime physical activity (IT and S, P<0.0001). There was a significant decline of BMD with age at the NN and S regions ( P<0.026), and the PD increased with age (NN and S, P<0.019). Previous fracture history was associated with having lower values of BMD, SM and CSA (except for S; P<0.022). Both section modulus and CSA were positively associated with heavy physical activity after age 50 years in all regions ( P<0.019), whereas NN BMD was the only BMD associate of heavy physical activity after 50 ( P=0.036). Time spent per week on recreational activities classified as no impact activity was positively associated with BMD, CSA and SM (multivariate P<0.016). In conclusion, proximal femur diameter is associated positively with reported life-long physical activity. If this is mediated through a loading related effect on sub-periosteal expansion, BMD would be an unsatisfactory outcome measure in physical activity studies since it is inversely related to projected bone area. SM in contrast was associated with several measures of recent physical activity and relates more directly to the bending experienced by the proximal femur in response to a given load. These data are consistent with an effect of mechanical loading to regulate bone strength through an anabolic effect maximal in the subperiosteal cortex, where the highest loading-related strains are experienced.

Residential area deprivation predicts smoking habit independently of individual educational level and occupational social class. A cross sectional study in the Norfolk cohort of the European Investigation into Cancer (EPIC-Norfolk)

OBJECTIVES

To investigate the independent association between individual and area based measures of socioeconomic status and cigarette smoking habit.

DESIGN AND SETTING

Cross sectional, population based study.

PARTICIPANTS AND METHODS

12 579 men and 15 132 women aged 39-79 years living in the general community participating in the EPIC-Norfolk Study in 1993-1997. The association between social class, educational status, Townsend residential deprivation level, and cigarette smoking status was examined.

MAIN OUTCOME MEASURES

Cigarette smoking status at baseline survey.

RESULTS

Social class, educational level, and residential deprivation level independently related to cigarette smoking habit in both men and women. Multivariate age adjusted odds ratios for current smoking in men were 1.62 (95% CI 1.45 to 1.81) for manual compared with non-manual social class, 1.32 (95% CI 1.17 to 1.48) for those with educational level less than O level compared with those with O level qualifications or higher and 1.84 (95% CI 1.62 to 2.08) for high versus low area deprivation level. For women, the odds ratios for current smoking for manual social class were 1.14 (95% CI 1.03 to 1.27); 1.31 (95% CI 1.18 to 1.46) for low educational level and 1.68 (95% CI 1.49 to 1.90) for high residential deprivation respectively.

CONCLUSIONS

Residential deprivation level using the Townsend score, individual social class, and educational level all independently predict smoking habit in both men and women. Efforts to reduce cigarette smoking need to tackle not just individual but also area based factors. Understanding the specific factors in deprived areas that influence smoking habit may help inform preventive efforts.

Physical activity of subjects aged 50-64 years involved in the European Prospective Investigation into Cancer and Nutrition (EPIC)

OBJECTIVE

To describe physical activity of participants in the European Prospective Investigation into Cancer and Nutrition (EPIC).

DESIGN

A cross-sectional analysis of baseline data of a European prospective cohort study.

SUBJECTS

This analysis was restricted to participants in the age group 50-64 years, which was represented in all EPIC centres. It involved 236 386 participants from 25 centres in nine countries. In each EPIC centre, physical activity was assessed by standardised and validated questions. Frequency distribution of type of professional activity and participation in non-professional activities, and age-adjusted means, medians and percentiles of time dedicated to non-professional activities are presented for men and women from each centre.

RESULTS

Professional activity was most frequently classified as sedentary or standing in all centres. There was a wide variation regarding participation in different types of non-professional activities and time dedicated to these activities across EPIC centres. Over 80% of all EPIC participants engaged in walking, while less than 50% of the subjects participated in sport. Total time dedicated to recreational activities was highest among the Dutch participants and lowest among men from Malmö (Sweden) and women from Naples (Italy). In all centres, total time dedicated to recreational activity in the summer was higher than in the winter. Women from southern Europe spent the most time on housekeeping.

CONCLUSIONS

There is a considerable variation of physical activity across EPIC centres. This variation was especially evident for recreational activities in both men and women.

Nutritional methods in the European Prospective Investigation of Cancer in Norfolk

OBJECTIVE

To describe methods and dietary habits of a large population cohort.

DESIGN

Prospective assessment of diet using diet diaries and food-frequency questionnaires, and biomarkers of diet in 24-h urine collections and blood samples.

SETTING

Free living individuals aged 45 to 75 years living in Norfolk, UK.

SUBJECTS

Food and nutrient intake from a food-frequency questionnaire on 23 003 men and women, and from a 7-day diet diary from 2117 men and women. Nitrogen, sodium and potassium excretion was obtained from single 24-h urine samples from 300 individuals in the EPIC cohort. Plasma vitamin C was measured for 20 846 men and women.

RESULTS

The food-frequency questionnaire (FFQ) and the food diary were able to determine differences in foods and nutrients between the sexes and were reliable as judged by repeated administrations of each method. Plasma vitamin C was significantly higher in women than men. There were significant differences in mean intake of all nutrients measured by the two different methods in women but less so in men. The questionnaire overestimated dairy products and vegetables in both men and women when compared with intakes derived from the diary, but underestimated cereal and meat intake in men. There were some consistent trends with age in food and nutrient intakes assessed by both methods, particularly in men. Correlation coefficients between dietary intake assessed from the diary and excretion of nitrogen and potassium in a single 24-h urine sample ranged from 0.36 to 0.47. Those comparing urine excretion and intake assessed from the FFQ were 0.09 to 0.26. The correlations between plasma vitamin C and dietary intake from the first FFQ, 24-h recall or diary were 0.28, 0.35 and 0.40.

CONCLUSIONS

EPIC Norfolk is one of the largest epidemiological studies of nutrition in the UK and the largest on which plasma vitamin C has been obtained. Methods for obtaining food and nutrient intake are described in detail. The results shown here for food and nutrient intakes can be compared with results from other population studies utilising different methods of assessing dietary intake. The utility of different methods used in different settings within the main EPIC cohort is described. The FFQ is to be used particularly in pooled analyses of risk from diet in relation to cancer incidence within the larger European EPIC study, where measurement error is more likely to be overcome by large dietary heterogeneity on an international basis. Findings in the UK, where dietary variation between individuals is smaller and hence the need to use a more accurate individual method greater, will be derived from the 7-day diary information on a nested case-control basis. 24-h recalls can be used in the event that diary information should not be forthcoming from some eventual cases. Combinations of results utilising all dietary methods and biomarkers may also be possible.

Relation between plasma ascorbic acid and mortality in men and women in EPIC-Norfolk prospective study: a prospective population study. European Prospective Investigation into Cancer and Nutrition

BACKGROUND

Ascorbic acid (vitamin C) might be protective for several chronic diseases. However, findings from prospective studies that relate ascorbic acid to cardiovascular disease or cancer are not consistent. We aimed to assess the relation between plasma ascorbic acid and subsequent mortality due to all causes, cardiovascular disease, ischaemic heart disease, and cancer.

METHODS

We prospectively examined for 4 years the relation between plasma ascorbic acid concentrations and mortality due to all causes, and to cardiovascular disease, ischaemic heart disease, and cancer in 19 496 men and women aged 45-79 years. We recruited individuals by post using age-sex registers of general practices. Participants completed a health and lifestyle questionnaire and were examined at a clinic visit. They were followed-up for causes of death for about 4 years. Individuals were divided into sex-specific quintiles of plasma ascorbic acid. We used the Cox proportional hazard model to determine the effect of ascorbic acid and other risk factors on mortality.

FINDINGS

Plasma ascorbic acid concentration was inversely related to mortality from all-causes, and from cardiovascular disease, and ischaemic heart disease in men and women. Risk of mortality in the top ascorbic acid quintile was about half the risk in the lowest quintile (p<0.0001). The relation with mortality was continuous through the whole distribution of ascorbic acid concentrations. 20 micromol/L rise in plasma ascorbic acid concentration, equivalent to about 50 g per day increase in fruit and vegetable intake, was associated with about a 20% reduction in risk of all-cause mortality (p<0.0001), independent of age, systolic blood pressure, blood cholesterol, cigarette smoking habit, diabetes, and supplement use. Ascorbic acid was inversely related to cancer mortality in men but not women.

INTERPRETATION

Small increases in fruit and vegetable intake of about one serving daily has encouraging prospects for possible prevention of disease.