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Kim Overvad

Publications and source records attributed to Kim Overvad.

At least 55 records · Page 3Linked to original sources

Anthropometry, physical activity, and the risk of pancreatic cancer in the European prospective investigation into cancer and nutrition.

Tobacco smoking is the only established risk factor for pancreatic cancer. Results from several epidemiologic studies have suggested that increased body mass index and/or lack of physical activity may be associated with an increased risk of this disease. We examined the relationship between anthropometry and physical activity recorded at baseline and the risk of pancreatic cancer in the European Prospective Investigation into Cancer and Nutrition (n = 438,405 males and females age 19-84 years and followed for a total of 2,826,070 person-years). Relative risks (RR) were calculated using Cox proportional hazards models stratified by age, sex, and country and adjusted for smoking and self-reported diabetes and, where appropriate, height. In total, there were 324 incident cases of pancreatic cancer diagnosed in the cohort over an average of 6 years of follow-up. There was evidence that the RR of pancreatic cancer was associated with increased height [RR, 1.74; 95% confidence interval (95% CI), 1.20-2.52] for highest quartile compared with lowest quartile (P(trend) = 0.001). However, this trend was primarily due to a low risk in the lowest quartile, as when this group was excluded, the trend was no longer statistically significant (P = 0.27). A larger waist-to-hip ratio and waist circumference were both associated with an increased risk of developing the disease (RR per 0.1, 1.24; 95% CI, 1.04-1.48; P(trend) = 0.02 and RR per 10 cm, 1.13; 95% CI, 1.01-1.26; P(trend) = 0.03, respectively). There was a nonsignificant increased risk of pancreatic cancer with increasing body mass index (RR, 1.09; 95% CI, 0.95-1.24 per 5 kg/m(2)), and a nonsignificant decreased risk with total physical activity (RR, 0.82; 95% CI, 0.50-1.35 for most active versus inactive). Future studies should consider including measurements of waist and hip circumference, to further investigate the relationship between central adiposity and the risk of pancreatic cancer.

Adult↗

Polymorphisms in metabolic genes related to tobacco smoke and the risk of gastric cancer in the European prospective investigation into cancer and nutrition.

Metabolizing enzymes, which often display genetic polymorphisms, are involved in the activation of compounds present in tobacco smoke that may be relevant to gastric carcinogenesis. We report the results of a study looking at the association between risk of gastric adenocarcinoma and polymorphisms in genes CYP1A1, CYP1A2, EPHX1, and GSTT1. A nested case-control study was carried out within the European Prospective Investigation into Cancer and Nutrition, developed in 10 European countries. The study includes 243 newly diagnosed cases of histologically confirmed gastric adenocarcinoma and 946 controls matched by center, age, sex, and date of blood collection. Genotypes were determined in nuclear DNA from WBCs. We found an increased risk of gastric cancer for homozygotes for C (histidine) variant in Y113H of EPHX1 (odds ratio, 1.91; 95% confidence interval, 1.19-3.07) compared with subjects with TC/TT. There was also a significant increased risk for smokers carrying at least one variant allele A in Ex7+129C>A (m4) of CYP1A1 and never smokers with null GSTT1 and allele A in the locus -3859G>A of CYP1A2. Most of these genes are involved in the activation and detoxification of polycyclic aromatic hydrocarbons, suggesting a potential role of these compounds in gastric carcinogenesis.

Adenocarcinoma↗

Physical activity and risk of colon and rectal cancers: the European prospective investigation into cancer and nutrition.

We investigated several aspects of the role of physical activity in colon and rectal cancer etiology that remain unclear in the European Prospective Investigation into Nutrition and Cancer. This cohort of 413,044 men and women had 1,094 cases of colon and 599 cases of rectal cancer diagnosed during an average of 6.4 years of follow-up. We analyzed baseline data on occupational, household, and recreational activity to examine associations by type of activity, tumor subsite, body mass index (BMI), and energy intake. The multivariate hazard ratio for colon cancer was 0.78 [95% confidence interval (95% CI), 0.59-1.03] among the most active participants when compared with the inactive, with evidence of a dose-response effect (P(trend) = 0.04). For right-sided colon tumors, the risk was 0.65 (95% CI, 0.43-1.00) in the highest quartile of activity with evidence of a linear trend (P(trend) = 0.004). Active participants with a BMI under 25 had a risk of 0.63 (95% CI, 0.39-1.01) for colon cancer compared with the inactive. Finally, an interaction between BMI and activity (P(interaction) = 0.03) was observed for right-sided colon cancers; among moderately active and active participants with a BMI under 25, a risk of 0.38 (95% CI, 0.21-0.68) was found as compared with inactive participants with BMI >30. No comparable decreased risks were observed for rectal cancer for any type of physical activity for any subgroup analyses or interactions considered. We found that physical activity reduced colon cancer risk, specifically for right-sided tumors and for lean participants, but not rectal cancer.

Body Mass Index↗

Prospective study of 8-oxo-7,8-dihydro-2'-deoxyguanosine excretion and the risk of lung cancer.

Oxidative damage to DNA may be important in carcinogenesis and a possible risk factor for lung cancer. The urinary excretion of products of damaged nucleotides in cellular pools or in DNA may be important biomarkers of exposure to relevant carcinogens reflecting the rate of damage in steady state and may predict cancer risk. Oxidation of guanine in DNA or the nucleotide pool may give rise to 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) for urinary excretion. Oxoguanine glycosylase (OGG1) is the base excision enzyme repairing 8-oxodG in DNA by release of 8-oxoguanine. In a nested case-cohort design we examined associations between urinary excretion of 8-oxodG and risk of lung cancer as well as potential interaction with the OGG1 Ser326Cys polymorphism in a population-based cohort of 25 717 men and 27 972 women aged 50-64 years with 3-7 years follow-up. We included 260 cases with lung cancer and a sub-cohort of 263 individuals matched on sex, age and smoking duration for comparison. Urine collected at entry was analysed for 8-oxodG by HPLC with electrochemical detection. The excretion of 8-oxodG was higher in current smokers, whereas OGG1 genotype had no effect. Overall the incidence rate ratio (IRR) (95% confidence interval) of lung cancer was 0.99 (0.80-1.22) per doubling of 8-oxodG excretion and there was no interaction with OGG1 genotype. However, among never-smokers (eight cases and eight sub-cohort members) the IRR was 11.8 (1.21-115) per doubling of 8-oxodG excretion. The association between 8-oxodG excretion and lung cancer risk among never-smokers suggests that oxidative damage to DNA nucleotides is important in this group.

8-Hydroxy-2'-Deoxyguanosine↗

Genetic variation in the HSD17B1 gene and risk of prostate cancer.

Steroid hormones are believed to play an important role in prostate carcinogenesis, but epidemiological evidence linking prostate cancer and steroid hormone genes has been inconclusive, in part due to small sample sizes or incomplete characterization of genetic variation at the locus of interest. Here we report on the results of a comprehensive study of the association between HSD17B1 and prostate cancer by the Breast and Prostate Cancer Cohort Consortium, a large collaborative study. HSD17B1 encodes 17beta-hydroxysteroid dehydrogenase 1, an enzyme that converts dihydroepiandrosterone to the testosterone precursor Delta5-androsterone-3beta,17beta-diol and converts estrone to estradiol. The Breast and Prostate Cancer Cohort Consortium researchers systematically characterized variation in HSD17B1 by targeted resequencing and dense genotyping; selected haplotype-tagging single nucleotide polymorphisms (htSNPs) that efficiently predict common variants in U.S. and European whites, Latinos, Japanese Americans, and Native Hawaiians; and genotyped these htSNPs in 8,290 prostate cancer cases and 9,367 study-, age-, and ethnicity-matched controls. We found no evidence that HSD17B1 htSNPs (including the nonsynonymous coding SNP S312G) or htSNP haplotypes were associated with risk of prostate cancer or tumor stage in the pooled multiethnic sample or in U.S. and European whites. Analyses stratified by age, body mass index, and family history of disease found no subgroup-specific associations between these HSD17B1 htSNPs and prostate cancer. We found significant evidence of heterogeneity in associations between HSD17B1 haplotypes and prostate cancer across ethnicity: one haplotype had a significant (p < 0.002) inverse association with risk of prostate cancer in Latinos and Japanese Americans but showed no evidence of association in African Americans, Native Hawaiians, or whites. However, the smaller numbers of Latinos and Japanese Americans in this study makes these subgroup analyses less reliable. These results suggest that the germline variants in HSD17B1 characterized by these htSNPs do not substantially influence the risk of prostate cancer in U.S. and European whites.

17-Hydroxysteroid Dehydrogenases↗

Associations between GPX1 Pro198Leu polymorphism, erythrocyte GPX activity, alcohol consumption and breast cancer risk in a prospective cohort study.

Breast cancer may be related to oxidative stress. Breast cancer patients have been reported to have lower antioxidant enzyme activity than healthy controls and the polymorphism GPX1 Pro198Leu has been associated with risk of lung and breast cancer. The purpose of the present nested case-control study was to determine whether GPX1 Pro198Leu and glutathione peroxidase (GPX) activity in prospectively collected blood samples are associated with breast cancer risk among postmenopausal women and whether GPX activity levels are associated with other known breast cancer risk factors. We matched 377 female breast cancer cases with 377 controls all nested within the prospective 'Diet, Cancer and Health' study of 57 000 Danes. Carriers of the variant T-allele of GPX1 Pro198Leu were at 1.43-fold higher risk of breast cancer compared with non-carriers (95% CI=1.07-1.92). Pre-diagnostic GPX activity tended to be lower in cases compared with controls. GPX activity was positively correlated with intake of alcohol (P<0.0001) and the catalytic activity was lowered 5% for each additional copy of the variant T-allele (P=0.0003). Alcohol intake was correlated with increased GPX activity for the C-allele but not for the T-allele. Results from this prospective study suggest that the GPX1 Pro198Leu-associated lowered GPX activity is associated with higher breast cancer risk among Danish women.

Alcohol Drinking↗

Physical activity and risk for lung cancer in a Danish cohort.

Physical activity might reduce the risk for lung cancer by various mechanisms, but the evidence is inconclusive. We therefore examined the relationship between physical activity and risk for lung cancer in a large population-based Danish cohort with detailed information about number of hours per week spent on specific physical activities as well as lifetime smoking patterns. Between 1993 and 1997, a total of 57,053 persons aged 50-64 years agreed to participate in the cohort. After exclusions of persons with cancer diagnosis before invitation and persons for whom data regarding study variables were missing, 26,070 men and 28,352 women remained for study. By 31 December 2002, lung cancer had been diagnosed in 194 men and 175 women. A questionnaire registered average number of hours per week spent on each of 6 types of leisure time physical activity. Level of occupational physical activity was registered in 5 categories. Cox's proportional hazard model stratified according to age at entry (1-year intervals) was adjusted for smoking, school education, possible occupational exposure to lung carcinogens and intake of fruit and vegetables. No significant association was found between number of hours per week spent on 6 types of physical activity during leisure time and the incidence rate ratio (IRR) for lung cancer. For each type of activity, the IRR of lung cancer was lower for active compared to nonactive women, whereas for men lower IRRs were only observed for sports and gardening. Higher levels of occupational physical activity had no protective effect; the lowest IRR was found for sitting work. Our study shows no convincing protective effect of physical activity on lung cancer risk.

Activities of Daily Living↗

DNA adducts and lung cancer risk: a prospective study.

Objectives were to investigate prospectively the ability of DNA adducts to predict cancer and to study the determinants of adducts, especially air pollutants. DNA adducts were measured in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC) investigation. Cases included newly diagnosed lung cancer (n = 115), upper respiratory cancers (pharynx and larynx; n = 82), bladder cancer (n = 124), leukemia (n = 166), and chronic obstructive pulmonary disease or emphysema deaths (n = 77) accrued after a median follow-up of 7 years among the EPIC former smokers and never-smokers. Three controls per case were matched for questionnaire analyses and two controls per case for laboratory analyses. Matching criteria were gender, age, smoking status, country of recruitment, and follow-up time. Individual exposure to air pollution was assessed using concentration data from monitoring stations in routine air quality monitoring networks. Leukocyte DNA adducts were analyzed blindly using 32P postlabeling technique. Adducts were associated with the subsequent risk of lung cancer, with an odds ratio (OR) of 1.86 [95% confidence interval (95% CI), 0.88-3.93] when comparing detectable versus nondetectable adducts. The association with lung cancer was stronger in never-smokers (OR, 4.04; 95% CI, 1.06-15.42) and among the younger age groups. After exclusion of the cancers occurring in the first 36 months of follow-up, the OR was 4.16 (95% CI, 1.24-13.88). A positive association was found between DNA adducts and ozone (O3) concentration. Our prospective study suggests that leukocyte DNA adducts may predict lung cancer risk of never-smokers. Besides, the association of DNA adduct levels with O3 indicates a possible role for photochemical smog in determining DNA damage.

Adult↗

Organochlorines in Danish women: predictors of adipose tissue concentrations.

Organochlorines (OCs) are ubiquitously present in the environment, and food of animal origin is currently reported as the major source of exposure. Carcinogenicity in animals raises concern, and OCs may also be a risk factor for both neurological and immunological effects. Our primary objective was to study predictors of adipose tissue levels of dichlorodiphenyldichloroethylene (DDE) and polychlorinated biphenyls (PCBs) in Danish women. We showed that adipose tissue concentrations of DDE and PCBs were consistently positively associated with age and the consumption of fish with a high fat content, while total lifetime duration of lactation had an inverse relationship. The direction of the association with body mass index (BMI) depended on the OC studied. The consumption of meat, fruit, lean fish, medium-fat-content fish, poultry, and eggs was not associated with OC concentrations in our study. We classified fish according to fat percentage, which seems more relevant than considering only total fish consumption. When PCBs were subdivided according to their chemical structure, similar results were obtained for the mono-, di-, and tri-ortho PCBs, indicating that PCBs can be treated as a homogenous group when studying predictors of concentrations in humans. In conclusion, the present study shows that age, lactation, and BMI are consistent predictors of human adipose tissue concentrations of DDE and PCBs and that dietary factors other than fish with a high fat content are not important predictors of these concentrations.

Adipose Tissue↗

An approach to estimate between- and within-group correlation coefficients in multicenter studies: plasma carotenoids as biomarkers of intake of fruits and vegetables.

In a multicenter study, the overall correlation between two variables can be broken down into a within- and a between-group correlation reflecting associations at the individual and aggregate levels, respectively. A random-effects model is used to estimate variance components of nutrition-related variables and the within- and between-group correlation coefficients. Using data from the European Prospective Investigation into Cancer and Nutrition (EPIC), the authors analyzed the association between levels of three plasma carotenoids (alpha-carotene, beta-cryptoxanthin, and lycopene) and dietary intake of three items (total fruits, carrots, and tomatoes), assessed through dietary questionnaire and single 24-hour dietary recall measurements, in a cross-sectional study involving 3,089 subjects from nine European countries. Intraclass correlation coefficients were 0.178 for alpha-carotene, 0.216 for beta-cryptoxanthin, and 0.299 for lycopene. The between-group correlation coefficients were higher than the within-group coefficients for all three carotenoids. For beta-cryptoxanthin and fruit intake, the between-group versus the within-group correlations were 0.78 and 0.26 for the dietary questionnaire and 0.85 and 0.19 for the 24-hour dietary recall. Results indicate that variability of exposure is driven mainly by the individual compared with the aggregate variation and that biomarker levels perform fairly accurately in discriminating population-level consumption of fruits and vegetables.

Adult↗

A genetic polymorphism in prostaglandin synthase 2 (8473, T-->C) and the risk of lung cancer.

Prostaglandin synthase 2 (PTGS2) mediated production of prostaglandins is an important step in the inflammatory response. In a population-based case-cohort study, we investigated the relationship between lung cancer and a polymorphism in PTGS2 at site 8473. Among 54,220 cohort members, 265 lung cancer cases and a comparison group of 272 individuals were identified. We found no overall significant association between the PTGS2 polymorphism and lung cancer risk, though the results indicated a lower risk in subjects carrying one copy (RR 0.87; 95% CI 0.61-1.25) or two copies (RR 0.58; 95% CI 0.30-1.12) of the variant allele compared with subjects carrying two copies of the wildtype allele. This tendency seemed to be strongest among the youngest subjects (50-55 years) with a RR on 0.48 (0.19-1.22) in carriers of one variant allele and 0.21 (0.04-1.07) in carriers of two variant alleles, and a significant trend (P=0.04). These results indicate that PTGS2 could be implicated in the development of lung cancer.

Aged↗

Meat, fish, and colorectal cancer risk: the European Prospective Investigation into cancer and nutrition.

BACKGROUND: Current evidence suggests that high red meat intake is associated with increased colorectal cancer risk. High fish intake may be associated with a decreased risk, but the existing evidence is less convincing. METHODS: We prospectively followed 478 040 men and women from 10 European countries who were free of cancer at enrollment between 1992 and 1998. Information on diet and lifestyle was collected at baseline. After a mean follow-up of 4.8 years, 1329 incident colorectal cancers were documented. We examined the relationship between intakes of red and processed meat, poultry, and fish and colorectal cancer risk using a proportional hazards model adjusted for age, sex, energy (nonfat and fat sources), height, weight, work-related physical activity, smoking status, dietary fiber and folate, and alcohol consumption, stratified by center. A calibration substudy based on 36 994 subjects was used to correct hazard ratios (HRs) and 95% confidence intervals (CIs) for diet measurement errors. All statistical tests were two-sided. RESULTS: Colorectal cancer risk was positively associated with intake of red and processed meat (highest [>160 g/day] versus lowest [<20 g/day] intake, HR = 1.35, 95% CI = 0.96 to 1.88; Ptrend = .03) and inversely associated with intake of fish (>80 g/day versus <10 g/day, HR = 0.69, 95 % CI = 0.54 to 0.88; Ptrend<.001), but was not related to poultry intake. Correcting for measurement error strengthened the associations between colorectal cancer and red and processed meat intake (per 100-g increase HR = 1.25, 95% CI =1.09 to 1.41, Ptrend = .001 and HR = 1.55, 95% CI = 1.19 to 2.02, Ptrend = .001 before and after calibration, respectively) and for fish (per 100 g increase HR = 0.70, 95% CI = 0.57 to 0.87, Ptrend<.001 and HR = 0.46, 95% CI = 0.27 to 0.77, Ptrend = .003; before and after correction, respectively). In this study population, the absolute risk of development of colorectal cancer within 10 years for a study subject aged 50 years was 1.71% for the highest category of red and processed meat intake and 1.28% for the lowest category of intake and was 1.86% for subjects in the lowest category of fish intake and 1.28% for subjects in the highest category of fish intake. CONCLUSIONS: Our data confirm that colorectal cancer risk is positively associated with high consumption of red and processed meat and support an inverse association with fish intake.

Adult↗

Serum sex steroids in premenopausal women and breast cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC).

BACKGROUND: Contrasting etiologic hypotheses about the role of endogenous sex steroids in breast cancer development among premenopausal women implicate ovarian androgen excess and progesterone deficiency, estrogen excess, estrogen and progesterone excess, and both an excess or lack of adrenal androgens (dehydroepiandrosterone [DHEA] or its sulfate [DHEAS]) as risk factors. We conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition cohort to examine associations among premenopausal serum concentrations of sex steroids and subsequent breast cancer risk. METHODS: Levels of DHEAS, (Delta4-)androstenedione, testosterone, and sex hormone binding globulin (SHBG) were measured in single prediagnostic serum samples from 370 premenopausal women who subsequently developed breast cancer (case patients) and from 726 matched cancer-free control subjects. Levels of progesterone, estrone, and estradiol were also measured for the 285 case patients and 555 matched control subjects who had provided information about the day of menstrual cycle at blood donation. Conditional logistic regression models were used to estimate relative risks of breast cancer by quartiles of hormone concentrations. All statistical tests were two-sided. RESULTS: Increased risks of breast cancer were associated with elevated serum concentrations of testosterone (odds ratio [OR] for highest versus lowest quartile = 1.73, 95% confidence interval [CI] = 1.16 to 2.57; P(trend) = .01), androstenedione (OR for highest versus lowest quartile = 1.56, 95% CI = 1.05 to 2.32; P(trend) = .01), and DHEAS (OR for highest versus lowest quartile = 1.48, 95% CI = 1.02 to 2.14; P(trend) = .10) but not SHBG. Elevated serum progesterone concentrations were associated with a statistically significant reduction in breast cancer risk (OR for highest versus lowest quartile = 0.61, 95% CI = 0.38 to 0.98; P(trend) = .06). The absolute risk of breast cancer for women younger than 40 followed up for 10 years was estimated at 2.6% for those in the highest quartile of serum testosterone versus 1.5% for those in the lowest quartile; for the highest and lowest quartiles of progesterone, these estimates were 1.7% and 2.6%, respectively. Breast cancer risk was not statistically significantly associated with serum levels of the other hormones. CONCLUSIONS: Our results support the hypothesis that elevated blood concentrations of androgens are associated with an increased risk of breast cancer in premenopausal women.

Adult↗

Combinations of polymorphisms in XPD, XPC and XPA in relation to risk of lung cancer.

Inherited polymorphisms in DNA repair genes may contribute to genetic susceptibility to cancer. XPA, XPC and XPD all encode proteins that are part of the nucleotide excision repair pathway. In a nested case-cohort study, we have investigated the occurrence of lung cancer in relation to commonly occurring polymorphisms in XPA, XPC and XPD. Among 54,220 members of a Danish prospective cohort study, 265 lung cancer cases were identified and a sub-cohort comprising 272 individuals was used for comparison. We found that XPA A23G and XPC Lys939Gln polymorphisms may be risk factors for lung cancer and evidence that positive interactions between the polymorphisms in XPA/XPD and XPC/XPD may occur.

DNA Helicases↗

Genetic polymorphisms in CYP1B1, GSTA1, NQO1 and NAT2 and the risk of lung cancer.

In a population-based case-cohort study, we have investigated the occurrence of lung cancer in relation to polymorphisms in the phase I gene cytochrome P450 1B1 and in the phase II genes glutathione S-transferase A1, NAD(P)H quinone oxidoreductase and N-acetyltransferase 2 (NAT2). Among 54,220 cohort members, 265 lung cancer cases were identified and a sub-cohort comprising 272 individuals was used for comparison. No overall associations were found between the polymorphisms and risk of lung cancer. The NAT2 fast acetylator genotype seemed to be protective against lung cancer in light smokers (< or =20 cigarettes/day) and not among heavy smokers (>20 cigarettes/day).

Aged↗