Epidemiological studies suggest that long-term exposure to road traffic noise increases the risk of cardiovascular disorders. The aim of this study was to investigate the relation between exposure to ...road traffic noise and risk for stroke, which has not been studied before.
In a population-based cohort of 57,053 people, we identified 1881 cases of first-ever stroke in a national hospital register between 1993-1997 and 2006. Exposure to road traffic noise and air pollution during the same period was estimated for all cohort members from residential address history. Associations between exposure to road traffic noise and stroke incidence were analysed in a Cox regression model with stratification for gender and calendar-year and adjustment for air pollution and other potential confounders. We found an incidence rate ratio (IRR) of 1.14 for stroke 95% confidence interval (CI): 1.03-1.25 per 10 dB higher level of road traffic noise (L(den)). There was a statistically significant interaction with age (P < 0.001), with a strong association between road traffic noise and stroke among cases over 64.5 years (IRR: 1.27; 95% CI: 1.13-1.43) and no association for those under 64.5 years (IRR: 1.02; 95% CI: 0.91-1.14).
Exposure to residential road traffic noise was associated with a higher risk for stroke among people older than 64.5 years of age.
Aims/hypothesis
The aim of this study was to investigate whether air pollution from traffic at a residence is associated with mortality related to type 1 or type 2 diabetes.
Methods
We followed up ...52,061 participants in the Danish Diet, Cancer and Health cohort for diabetes-related mortality in the nationwide Register of Causes of Death, from baseline in 1993–1997 up to the end of 2009, and traced their residential addresses since 1971 in the Central Population Registry. We used dispersion-modelled concentration of nitrogen dioxide (NO
2
) since 1971 and amount of traffic at the baseline residence as indicators of traffic-related air pollution and used Cox regression models to estimate mortality-rate ratios (MRRs) with adjustment for potential confounders.
Results
Mean levels of NO
2
at the residence since 1971 were significantly associated with mortality from diabetes. Exposure above 19.4 μg/m
3
(upper quartile) was associated with a MRR of 2.15 (95% CI 1.21, 3.83) when compared with below 13.6 μg/m
3
(lower quartile), corresponding to an MRR of 1.31 (95% CI 0.98, 1.76) per 10 μg/m
3
NO
2
after adjustment for potential confounders.
Conclusions/interpretation
This study suggests that traffic-related air pollution is associated with mortality from diabetes. If confirmed, reduction in population exposure to traffic-related air pollution could be an additional strategy against the global public health burden of diabetes.
Heavy children have an increased risk of being overweight young adults. Whether this risk remains in late adulthood is not well-understood. We investigated body mass index (BMI; kg m(-2)) tracking ...from childhood to late adulthood.
From the Copenhagen School Health Records Register, 72 959 men and 25 252 women born between 1930 and 1989 with BMI values at 7 and/or 13 years and as adults were included. Using a meta-regression approach, age- and sex-specific partial correlation analyses and logistic regressions were performed.
Correlations between BMI at 7 years and young adult ages (18-19 years) were r=0.55 for men and r=0.55 for women. At late ages (60-69 years) these were r=0.28 for men and r=0.26 for women. The correlations did not differ by birth years. Compared with normal-weight 7-year-olds, overweight children had a higher odds of overweight at 18-19 years; odds ratio (OR)=14.02 (95% confidence interval (CI): 12.14-16.19) for men and 10.46 (95% CI: 4.82-22.70) for women. At ages 60-69 years ORs were 5.46 (95% CI: 0.95-31.36) for men and 1.61 (95% CI: 0.83-3.15) for women. Correlations and ORs were stronger at age 13 years than age 7 years as expected, but the overall patterns were similar.
BMI tracking was weaker at late adult ages than at young adult ages. Although BMI tracks across the life course, childhood BMI is relatively poor at identifying later adult overweight or obesity at ages when chronic diseases generally emerge.
Essentials
Impact of cancer stage on venous thromboembolism (VTE) risk is not well‐known in all cancers.
The Scandinavian Thrombosis and Cancer Cohort provides person‐time data and validated VTEs.
...Impact of cancer stage on VTE incidence tended to vary with cancer type.
Cancer stage may not per se be a risk factor for VTE in all cancer types.
Summary
Background
Absolute measures of the impact of cancer stage on the incidence of venous thromboembolism (VTE) in patients with distinct cancer types have not been investigated in a large population‐based cohort study.
Objectives
To investigate differences in the incidence rates of objectively confirmed VTE according to the development of cancer in a large population‐based cohort study. Cancer type and stage at the time of diagnosis were taken into account.
Patients and Methods
The Scandinavian Thrombosis and Cancer Cohort includes data regarding cancer types, stages and objectively confirmed VTE diagnoses among 144 952 participants followed from 1993 to 2012. We studied stage‐specific incidence rates of VTE, and calculated incidence rate differences (IRDs) for VTE according to stages in patients with 10 types of solid cancer.
Results
During the entire follow‐up, 335 VTEs occurred, of which 293 occurred within 5 years. The IRD of VTE in patients with distant metastasis as compared with those with localized disease indicated large variation depending on cancer type. The highest IRD was observed for pancreatic cancer (IRD of 187.0 × 10−3 person‐years p‐y; 95% confidence interval CI − 6.7 to 380.8), and the lowest IRD was observed for prostate cancer (IRD of 3.7 × 10−3 p‐y; 95% CI − 7 to 15.2). Regional spread as compared with localized disease also indicated large variation depending on cancer type; the highest IRD was observed for uterine cancer (IRD of 37.6 × 10−3 p‐y; 95% CI − 23.7 to 99), and the IRDs for breast and prostate cancer were close to zero.
Conclusion
More advanced cancer at the time of diagnosis was associated with a higher risk of VTE, but the strength of the associations differed substantially between cancer types.
Summary Background Associations between circulating concentrations of oestrogens, progesterone, and androgens with breast cancer and related risk factors in premenopausal women are not well ...understood. We aimed to characterise these associations with a pooled analysis of data from seven studies. Methods Individual participant data for prediagnostic sex hormone and sex hormone-binding globulin (SHBG) concentrations were contributed from seven prospective studies. We restricted analyses to women who were premenopausal and younger than 50 years at blood collection, and to women with breast cancer diagnosed before age 50 years. We estimated odds ratios (ORs) with 95% CIs for breast cancer associated with hormone concentrations by conditional logistic regression in cases and controls matched for age, date of blood collection, and day of cycle, with stratification by study and further adjustment for cycle phase. We examined associations of hormones with risk factors for breast cancer in control women by comparing geometric mean hormone concentrations in categories of these risk factors, adjusted for study, age, phase of menstrual cycle, and body-mass index (BMI). All statistical tests were two-sided. Findings We included data for up to 767 women with breast cancer and 1699 controls in the risk analyses. Breast cancer risk was associated with a doubling in concentrations of oestradiol (OR 1·19, 95% CI 1·06–1·35), calculated free oestradiol (1·17, 1·03–1·33), oestrone (1·27, 1·05–1·54), androstenedione (1·30, 1·10–1·55), dehydroepiandrosterone sulphate (1·17, 1·04–1·32), testosterone (1·18, 1·03–1·35), and calculated free testosterone (1·08, 0·97–1·21). Breast cancer risk was not associated with luteal phase progesterone (doubling in concentration OR 1·00, 95% CI 0·92–1·09), and adjustment for other factors had little effect on any of these ORs. Cross-sectional analyses in control women showed several associations of sex hormones with breast cancer risk factors. Interpretation Circulating oestrogens and androgens are positively associated with the risk for breast cancer in premenopausal women. Funding Cancer Research UK.
Objectives To evaluate the association between a simple lifestyle index based on the recommendations for five lifestyle factors and the incidence of colorectal cancer, and to estimate the proportion ...of colorectal cancer cases attributable to lack of adherence to the recommendations.Design Prospective cohort study.Setting General population of Copenhagen and Aarhus, Denmark.Participants 55 487 men and women aged 50-64 years at baseline (1993-7), not previously diagnosed with cancer.Main outcome measure Risk of colorectal cancer in relation to points achieved in the lifestyle index (based on physical activity, waist circumference, smoking, alcohol intake, and diet (dietary fibre, energy percentage from fat, red and processed meat, and fruits and vegetables)) modelled through Cox regression.Results During a median follow-up of 9.9 years, 678 men and women had colorectal cancer diagnosed. After adjustment for potential confounders, each additional point achieved on the lifestyle index, corresponding to one additional recommendation that was met, was associated with a lower risk of colorectal cancer (incidence rate ratio 0.89 (95% confidence interval 0.82 to 0.96). In this population an estimated total of 13% (95% CI 4% to 22%) of the colorectal cancer cases were attributable to lack of adherence to merely one additional recommendation among all participants except the healthiest. If all participants had followed the five recommendations 23% (9% to 37%) of the colorectal cancer cases might have been prevented. Results were similar for colon and rectal cancer, but only statistically significant for colon cancer.Conclusions Adherence to the recommendations for physical activity, waist circumference, smoking, alcohol intake, and diet may reduce colorectal cancer risk considerably, and in this population 23% of the cases might be attributable to lack of adherence to the five lifestyle recommendations. The simple structure of the lifestyle index facilitates its use in public health practice.
Summary
Background
There are plausible mechanisms for how dietary docosahexaenoic acid (DHA), an n−3 polyunsaturated fatty acid, could prevent Crohn's disease (CD).
Aim
To conduct a prospective study ...to investigate the association between increased intake of DHA and risk of CD.
Methods
Overall, 229 702 participants were recruited from nine European centres between 1991 and 1998. At recruitment, dietary intakes of DHA and fatty acids were measured using validated food frequency questionnaires. The cohort was monitored through to June 2004 to identify participants who developed incident CD. In a nested case–control analysis, each case was matched with four controls; odds ratios (ORs) were calculated for quintiles of DHA intake, adjusted for total energy intake, smoking, other dietary fatty acids, dietary vitamin D and body mass index.
Results
Seventy‐three participants developed incident CD. All higher quintiles of DHA intake were inversely associated with development of CD; the highest quintile had the greatest effect size (OR = 0.07; 95% CI = 0.02–0.81). The OR trend across quintiles of DHA was 0.54 (95% CI = 0.30–0.99, Ptrend = 0.04). Including BMI in the multivariate analysis, due to its correlation with dietary fat showed similar associations. There were no associations with the other dietary fatty acids studied.
Conclusion
There were inverse associations, with a biological gradient between increasing dietary docosahexaenoic acid intakes and incident Crohn's disease. Further studies in other populations should measure docosahexaenoic acid to determine if the association is consistent and the hypothesis tested in randomised controlled trials of purely docosahexaenoic acid supplementation.
Dietary linoleic acid, an n-6 polyunsaturated fatty acid, is metabolised to arachidonic acid, a component of colonocyte membranes. Metabolites of arachidonic acid have pro-inflammatory properties and ...are increased in the mucosa of patients with ulcerative colitis. The aim of this investigation was to conduct the first prospective cohort study investigating if a high dietary intake of linoleic acid increases the risk of developing incident ulcerative colitis.
Dietary data from food frequency questionnaires were available for 203 193 men and women aged 30-74 years, resident in the UK, Sweden, Denmark, Germany or Italy and participating in a prospective cohort study, the European Prospective Investigation into Cancer and Nutrition (EPIC). These participants were followed up for the diagnosis of ulcerative colitis. Each case was matched with four controls and the risk of disease calculated by quartile of intake of linoleic acid adjusted for gender, age, smoking, total energy intake and centre.
A total of 126 participants developed ulcerative colitis (47% women) after a median follow-up of 4.0 years (range, 1.7-11.3 years). The highest quartile of intake of linoleic acid was associated with an increased risk of ulcerative colitis (odds ratio (OR) = 2.49, 95% confidence interval (CI) = 1.23 to 5.07, p = 0.01) with a significant trend across quartiles (OR = 1.32 per quartile increase, 95% CI = 1.04 to 1.66, p = 0.02 for trend).
The data support a role for dietary linoleic acid in the aetiology of ulcerative colitis. An estimated 30% of cases could be attributed to having dietary intakes higher than the lowest quartile of linoleic acid intake.
Objectives/Background The objective was to validate the diagnoses of peripheral arterial disease (PAD) in the legs, obtained from national registers in Denmark. Methods In total, 1435 registered ...cases of PAD were identified in the Danish National Patient Registry among 57,053 middle aged participants from the Danish Diet, Cancer and Health cohort study. Validation was performed by reviewing all medical records using pre-specified criteria for a diagnosis of PAD. Results The overall positive predictive value (PPV) of PAD diagnoses was 69.4% 95% confidence interval (CI) 67.0–71.7. The PPV of diagnoses given in departments of vascular surgery was significantly higher than diagnoses given in other departments: 71.9% (95% CI 69.2–74.4) versus 58.3% (95% CI 52.2–64.2), respectively. In a sub-study, 141 potential cases of PAD also registered in the Danish National Vascular Registry were evaluated, and a PPV of 87.9% (95% CI 81.4–92.4) was found for these diagnoses. Conclusion More than 30% of the diagnoses of PAD notified in the Danish National Patient Registry were not valid, stressing the importance of validation when using register information for research purposes. In contrast, diagnoses obtained from the Danish National Vascular Registry had a high validity ready for use without further validation.
Although several studies have investigated the association of the Mediterranean diet with overall mortality or risk of specific cancers, data on overall cancer risk are sparse.
We examined the ...association between adherence to Mediterranean dietary pattern and overall cancer risk using data from the European Prospective Investigation Into Cancer and nutrition, a multi-centre prospective cohort study including 142,605 men and 335,873. Adherence to Mediterranean diet was examined using a score (range: 0-9) considering the combined intake of fruits and nuts, vegetables, legumes, cereals, lipids, fish, dairy products, meat products, and alcohol. Association with cancer incidence was assessed through Cox regression modelling, controlling for potential confounders.
In all, 9669 incident cancers in men and 21,062 in women were identified. A lower overall cancer risk was found among individuals with greater adherence to Mediterranean diet (hazard ratio=0.96, 95% CI 0.95-0.98) for a two-point increment of the Mediterranean diet score. The apparent inverse association was stronger for smoking-related cancers than for cancers not known to be related to tobacco (P (heterogeneity)=0.008). In all, 4.7% of cancers among men and 2.4% in women would be avoided in this population if study subjects had a greater adherence to Mediterranean dietary pattern.
Greater adherence to a Mediterranean dietary pattern could reduce overall cancer risk.