Jeanette Therming Jørgensen

Shift Work and Overall and Cause-Specific Mortality in the Danish Nurse Cohort

Objectives Evidence of an effect of shift work on all-cause and cause-specific mortality is inconsistent. This study aims to examine whether shift work is associated with increased all-cause and cause-specific mortality. Methods We linked 28 731 female nurses (age ≥44 years), recruited in 1993 or 1999 from the Danish nurse cohort where they reported information on shift work (night, evening, rotating, or day), to the Danish Register of Causes of Death to identify deaths up to 2013. We used Cox regression models with age as the underlying scale to examine the associations between night, evening, and rotating shift work (compared to day shift work) and all-cause and cause-specific mortality in models adjusted for potentially confounding variables. Results Of 18 015 nurses included in this study, 1616 died during the study time period from the following causes: cardiovascular disease (N=217), cancer (N= 945), diabetes (N=20), Alzheimers disease or dementia (N=33), and psychiatric diseases (N=67). We found that working night [hazard ratio (HR) 1.26, 95% confidence interval 95% CI) 1.05-1.51] or evening (HR 1.29, 95% CI 1.11-1.49) shifts was associated with a significant increase in all-cause mortality when compared to working day shift. We found a significant association of night shift work with cardiovascular disease (HR 1.71, 95% CI 1.09-2.69) and diabetes (HR 12.0, 95% CI 3.17-45.2, based on 8 cases) and none with overall cancer mortality (HR 1.05, 95% CI 0.81-1.35) or mortality from psychiatric diseases (HR 1.17, 95% CI 0.47-2.92). Finally, we found strong association between evening (HR 4.28, 95% CI 1.62-11.3) and rotating (HR 5.39, 95% CI 2.35-12.3) shift work and mortality from Alzheimers disease and dementia (based on 8 and 14 deaths among evening and rotating shift workers, respectively). Conclusions Women working night and evening shifts have increased all-cause, cardiovascular, diabetes, and Alzheimers and dementia mortality.

Long-Term Exposure to Ambient Air Pollution and Incidence of Postmenopausal Breast Cancer in 15 European Cohorts within the ESCAPE Project

Background: Epidemiological evidence on the association between ambient air pollution and breast cancer risk is inconsistent. Objective: We examined the association between long-term exposure to ambient air pollution and incidence of postmenopausal breast cancer in European women. Methods: In 15 cohorts from nine European countries, individual estimates of air pollution levels at the residence were estimated by standardized land-use regression models developed within the European Study of Cohorts for Air Pollution Effects (ESCAPE) and Transport related Air Pollution and Health impacts - Integrated Methodologies for Assessing Particulate Matter (TRANSPHORM) projects: particulate matter (PM) ≤2.5μm, ≤10μm, and 2.5–10μm in diameter (PM2.5, PM10, and PMcoarse, respectively); PM2.5 absorbance; nitrogen oxides (NO2 and NOx); traffic intensity; and elemental composition of PM. We estimated cohort-specific associations between breast cancer and air pollutants using Cox regression models, adjusting for major lifestyle risk factors, and pooled cohort-specific estimates using random-effects meta-analyses. Results: Of 74,750 postmenopausal women included in the study, 3,612 developed breast cancer during 991,353 person-years of follow-up. We found positive and statistically insignificant associations between breast cancer and PM2.5 {hazard ratio (HR)=1.08 [95% confidence interval (CI): 0.77, 1.51] per 5 μg/m3}, PM10 [1.07 (95% CI: 0.89, 1.30) per 10 μg/m3], PMcoarse [1.20 (95% CI: 0.96, 1.49 per 5 μg/m3], and NO2 [1.02 (95% CI: 0.98, 1.07 per 10 μg/m3], and a statistically significant association with NOx [1.04 (95% CI: 1.00, 1.08) per 20 μg/m3, p=0.04]. Conclusions: We found suggestive evidence of an association between ambient air pollution and incidence of postmenopausal breast cancer in European women. https://doi.org/10.1289/EHP1742

Long-term exposure to ambient air pollution and incidence of brain tumours: The Danish Nurse Cohort

BACKGROUND Air pollution has been considered a potent environmental risk factor for neuropathology through neuroinflammation and oxidative stress, which might also cause brain tumour formation. However, epidemiological evidence on the association between air pollution and brain tumours in humans is sparse, with no data on exposure to particles. In this study we aim to examine associations between long-term exposure to ambient air pollution and risk for development of brain tumours. METHODS We used the Danish Nurse Cohort with 28,731 female nurses (age≥44years) recruited in 1993 or 1999 when self-reported information on lifestyle was collected. We obtained data on the incidence of brain tumours until 2013 from the Danish Cancer Register, and estimated annual mean concentrations of particulate matter with diameter<2.5μm (PM2.5), particulate matter with diameter<10μm (PM10), nitrogen oxides (NOx) and nitrogen dioxide (NO2) at the residence since 1990 using an atmospheric integrated chemistry-transport models system, and examined the association between the 3-year running mean of pollutants and brain tumour incidence using time-varying Cox regression, separately for total brain tumours, and for tumour subtypes by location (brain or meninges), and by malignancy (malignant or benign), and estimated hazard ratios and 95% confidence intervals per increase in interquartile range of exposure. RESULTS Of 25,143 tumour-free nurses at recruitment, 121 developed brain cancer during 15.7 years of follow-up. We found a weak positive association between total brain tumours and PM2.5 (1.06; 0.80-1.40 per 3.37μg/m(3)), NO2 (1.09; 0.91-1.29) per 7.5μg/m(3), and NOx (1.02; 0.93-1.12 per 10.22μg/m(3)), and none with PM10 (0.93; 0.70-1.23 per 3.31μg/m(3)). Associations with PM2.5 and NO2 were stronger for tumours located in meninges than in brain, and for benign than for malignant tumours. Finally, association of total brain tumours with PM2.5 was modified by BMI, and was statistically significantly enhanced in obese women (2.03; 1.35-3.05). CONCLUSION We found weak evidence for association between risk of brain tumours and long-term exposure to air pollution in women older than 44 years. However, we present novel results that obese women may be susceptible, as well as a positive tendency towards elevated risk for meninges and benign tumours, which require further investigation.

Long-term exposure to ambient air pollution and incidence of brain tumor: the European Study of Cohorts for Air Pollution Effects (ESCAPE)

Abstract Background Epidemiological evidence on the association between ambient air pollution and brain tumor risk is sparse and inconsistent. Methods In 12 cohorts from 6 European countries, individual estimates of annual mean air pollution levels at the baseline residence were estimated by standardized land-use regression models developed within the ESCAPE and TRANSPHORM projects: particulate matter (PM) ≤2.5, ≤10, and 2.5–10 μm in diameter (PM2.5, PM10, and PMcoarse), PM2.5 absorbance, nitrogen oxides (NO2 and NOx) and elemental composition of PM. We estimated cohort-specific associations of air pollutant concentrations and traffic intensity with total, malignant, and nonmalignant brain tumor, in separate Cox regression models, adjusting for risk factors, and pooled cohort-specific estimates using random-effects meta-analyses. Results Of 282194 subjects from 12 cohorts, 466 developed malignant brain tumors during 12 years of follow-up. Six of the cohorts also had data on nonmalignant brain tumor, where among 106786 subjects, 366 developed brain tumor: 176 nonmalignant and 190 malignant. We found a positive, statistically nonsignificant association between malignant brain tumor and PM2.5 absorbance (hazard ratio and 95% CI: 1.67; 0.89–3.14 per 10–5/m3), and weak positive or null associations with the other pollutants. Hazard ratio for PM2.5 absorbance (1.01; 0.38–2.71 per 10–5/m3) and all other pollutants were lower for nonmalignant than for malignant brain tumors. Conclusion We found suggestive evidence of an association between long-term exposure to PM2.5 absorbance indicating traffic-related air pollution and malignant brain tumors, and no association with overall or nonmalignant brain tumors.

Determinants related to gender differences in general practice utilization: Danish Diet, Cancer and Health Cohort

Abstract Objective: This study aims to describe the determinants related to gender differences in the GP utilization in Danish population aged 50–65 years. Design: Cohort-based cross-sectional study. Setting: Danish general practice. Subjects: Totally, 54,849 participants of the Danish Diet, Cancer and Health cohort (50–65 years). Main outcome measures: The sum of cohort members’ face-to-face consultations with general practitioner (GP) at the cohort baseline year (1993–1997). We obtained data on GP visits from the Danish National Health Service Register at the cohort baseline (1993–1997), when information on lifestyle (smoking, body mass index (BMI), alcohol use, physical activity), medical conditions (somatic and mental), employment, education, gravidity, and hormone therapy (HT) use was collected by questionnaire. Results: Women had on average 4.1 and men 2.8 consultations per year. In a crude model, women had 47% higher rate of GP visits than men (incidence rate ratio: 1.47; 95% Confidence Interval: 1.45–1.50), which remained unchanged after adjustment for lifestyle, socio-demographic and medical factors, but attenuated to 18% (1.18; 1.13–1.24) after adjustment for female factors (gravidity and post-menopausal HT. In a fully adjusted model, subjects with hypertension (1.63; 1.59–1.67), mental illness (1.63; 1.61–1.66), diabetes (1.56; 1.47–1.65), angina pectoris (1.28; 1.21–1.34), and unemployed persons (1.19; 1.18–1.21) had highest rates of GP visits. Conclusions: Gravidity and HT use explain a large proportion, but not all of the gender difference in GP utilization. Medical conditions (somatic and mental) and unemployment are the main determinants of GP utilization in men and women, while lifestyle has minor effect. Key points Female gender remained a dominant determinant of GP utilization, after adjustment for lifestyle, socio-demography, medical and gender specific factors, with females consulting their GP 18% more often than males. Female reproductive factors (use of postmenopausal hormone therapy and gravidity) explained a large proportion of the gender variation in use of GP. Strongest determinants for GP use among Danish adults aged 50–65 years were the presence of medical conditions (somatic and mental) and unemployment, while lifestyle factors (e.g., body mass index, alcohol consumption and smoking) had minor effect.

OP XI – 1 Long-term exposure to road traffic noise and incidence of myocardial infarction. a danish nurse cohort study

Background/aim Exposure to road traffic noise has been linked to adverse health effects, including cardiovascular diseases (CVD), however, evidence is inconsistent. In this study we examined the association between long-term exposure to road traffic noise and incidence of myocardial infarction (MI). Methods We used the data from a nationwide Danish Nurse Cohort on 22 438 female nurses (age >44 years) who at recruitment in 1993 or 1999 reported information on CVD risk factors. We obtained data on incidence of MI from the Danish National Patient Register until end of 2014. Road traffic noise levels at the nurses’ residences between 1970 and 2014 were estimated using The Nord2000 as the annual mean of a weighted 24 hour average (Lden). We used time-varying Cox regression models to examine the association between 24-, 10-, and 1 year running mean of Lden and MI incidence, in a crude model (adjusted for age and time of cohort enrolment) and in a fully adjusted model (adjusted for age, enrolment year, physical activity, alcohol, smoking, marital status, fruit consumption and use of hormone therapy). Results Of the 22 438 women, 590 developed MI during a mean follow-up of 18.3 years. Residential road traffic noise levels ranged from 5–82.7 dB at the year of cohort baseline. We found no association between exposure to road traffic noise and MI in crude (hazard ratio; 95% confidence interval: 0.94; 0.83–1.05) or fully (0.92; 0.82–1.04) adjusted model, for each 10 dB increase in 24 year mean road traffic noise levels. Similar results were found with 10 year and 1 year exposure windows. We observed a possible trend of increased risk, although statistically non-significant, in nurses living in urban areas (1.29; 0.84–2.00), and none in those living in provincial (0.98; 0.77–1.23) or rural (0.91; 0.77–1.07) areas (p for interaction 0.38). Conclusion We found no association between long-term exposure to road traffic noise and MI in the total population of Danish nurses. We present novel finding that nurses living in urban areas may be more susceptible to the effects of exposure to road traffic noise with respect to MI.

Effects of Leisure‐Time and Transport‐Related Physical Activities on the Risk of Incident and Recurrent Myocardial Infarction and Interaction With Traffic‐Related Air Pollution: A Cohort Study

Background Physical activity enhances the uptake of air pollutants, possibly reducing its beneficial effects. We examined the effects of leisure‐time and transport‐related physical activities on the risk of myocardial infarction (MI), and whether potential benefits on MI are reduced by exposure to traffic‐related air pollution. Methods and Results A group of 57 053 participants (50–65 years of age) from the Danish Diet, Cancer, and Health cohort reported physical activity at baseline (1993–1997) and were linked to registry data on hospital contacts and out‐of‐hospital deaths caused by MI, until December 2015. Nitrogen dioxide levels were estimated at participants’ baseline residences. We used Cox regressions to associate participation in sports, cycling, walking, and gardening with incident and recurrent MI, and tested for interaction by nitrogen dioxide. Of 50 635 participants without MI at baseline, 2936 developed incident MI, and of 1233 participants with MI before baseline, 324 had recurring MI during follow‐up. Mean nitrogen dioxide concentration was 18.7 μg/m3 at baseline (1993–1997). We found inverse statistically significant associations between participation in sports (hazard ratio; 95% confidence interval: 0.85; 0.79–0.92), cycling (0.91; 0.84–0.98), gardening (0.87; 0.80–0.95), and incident MI, while the association with walking was statistically nonsignificant (0.95; 0.83–1.08). Recurrent MI was statistically nonsignificantly inversely associated with cycling (0.80; 0.63–1.02), walking (0.82, 0.57–1.16), and gardening (0.91; 0.71–1.18), and positively with sports (1.06; 0.83–1.35). There was no effect modification of the associations between physical activity and MI by nitrogen dioxide. Conclusions Benefits of physical activity on both the incidence and the recurrence of MI are not reduced by exposure to high levels of air pollution.

0453 Shift work and overall and cause-specific mortality in the danish nurse cohort

Withdrawn at the author’s request

0247 Shift work and incidence of cardiovascular diseases in the danish nurse cohort

Objective Shift work and risk of cardiovascular diseases (CVD) have been investigated during many decades. The evidence is, however, still conflicting. This study aims to examine whether shift work among Danish female nurses is associated with the risk of CVD. Methods 28 731 women from the Danish Nurse cohort (>44 years old at recruitment in 1993 or 1999), who reported information on shift work (day, evening, night or rotating), were linked to the Danish National Patient Register, to obtain information on CVD (ICD-10: I00-99; ICD-8: 390–458) hospital contacts (emergency, in- or outpatient) from 1978 until August 2015. We used Cox regression models to examine the association between shift work and the incidence of CVD, defined as the first-ever hospital contact for CVD after cohort baseline, adjusting for the most important risk factors. Results Of 16 086 nurses without previous CVD events at baseline, 5504 developed CVD during a mean follow-up of 16 years, with an incidence rate of 21.4 cases per 1000 person-years. 63.4% of the nurses reported day work as their primary work schedule, while 10.0%, 5.3% and 21.6% worked in evening, night and rotating shifts, respectively. We found no associations between shift work and the risk of CVD when compared to day workers, with hazard ratio of 0.99 (95% confidence interval 0.91–1.09) for evening, 1.01 (0.90–1.13) for night and 1.03 (0.96–1.10) for rotating shifts, in the fully adjusted model. Conclusion We found no evidence of an increased risk of CVD among female shift workers.