Bilateral oophorectomy and rate of colorectal cancer: A prospective cohort study.

Worldwide, colorectal cancer is the second most common cancer and third cause of cancer death in women. Estrogen exposure has been inversely associated with colorectal cancer. Oophorectomy reduces circulating estrogen, but the effect on colorectal cancer remains uncertain. The aim of this study was to examine the association between unilateral and bilateral oophorectomy and subsequent risk of colorectal cancer, and whether this association varied by menopausal status at time of oophorectomy, use of hormone replacement therapy (HRT) at baseline, hysterectomy and baseline body mass index (BMI). The study included 25 698 female nurses (aged ≥45 years) participating in the Danish Nurse Cohort. Nurses were followed from baseline until date of colorectal cancer, death, emigration or end of follow-up at December 31, 2018, whichever came first. We examined the association between oophorectomy and colorectal cancer (all ages and stratified by menopausal status). The potential modifying effects of hysterectomy, HRT use at baseline and BMI were investigated. During 542 140 person-years of follow-up, 863 (3.4%) nurses were diagnosed with colorectal cancer. Bilateral oophorectomy was associated with a 79% increased colorectal cancer rate, adjusted rate ratio (aRR) (95% confidence interval [CI]): 1.79 (1.33-2.42). Effect estimates following unilateral oophorectomy also showed higher rate of colorectal cancer, although less pronounced and nonstatistically significant (aRR) (95% CI): 1.25 (0.86-1.82). Similar results were seen when stratifying by menopausal status. The association was not modified by baseline HRT use, hysterectomy or BMI. Oophorectomy was associated with increased rate of colorectal cancer, with highest rates among women with bilateral oophorectomy.

Stringency of COVID-19 Containment Response Policies and Air Quality Changes: A Global Analysis across 1851 Cities.

The COVID-19 containment response policies (CRPs) had a major impact on air quality (AQ). These CRPs have been time-varying and location-specific. So far, despite having numerous studies on the effect of COVID-19 lockdown on AQ, a knowledge gap remains on the association between stringency of CRPs and AQ changes across the world, regions, nations, and cities. Here, we show that globally across 1851 cities (each more than 300 000 people) in 149 countries, after controlling for the impacts of relevant covariates (e.g., meteorology), Sentinel-5P satellite-observed nitrogen dioxide (NO2) levels decreased by 4.9% (95% CI: 2.2, 7.6%) during lockdowns following stringent CRPs compared to pre-CRPs. The NO2 levels did not change significantly during moderate CRPs and even increased during mild CRPs by 2.3% (95% CI: 0.7, 4.0%), which was 6.8% (95% CI: 2.0, 12.0%) across Europe and Central Asia, possibly due to population avoidance of public transportation in favor of private transportation. Among 1768 cities implementing stringent CRPs, we observed the most NO2 reduction in more populated and polluted cities. Our results demonstrate that AQ improved when and where stringent COVID-19 CRPs were implemented, changed less under moderate CRPs, and even deteriorated under mild CRPs. These changes were location-, region-, and CRP-specific.

Road traffic noise and markers of adiposity in the Danish Nurse Cohort: A cross-sectional study.

BACKGROUND: Studies have suggested that traffic noise is associated with markers of obesity. We investigated the association of exposure to road traffic noise with body mass index (BMI) and waist circumference in the Danish Nurse Cohort. METHODS: We used data on 15,501 female nurses (aged >44 years) from the nationwide Danish Nurse Cohort who, in 1999, reported information on self-measured height, weight, and waist circumference, together with information on socioeconomic status, lifestyle, work and health. Road traffic noise at the most exposed façade of the residence was estimated using Nord2000 as the annual mean of a weighted 24-h average (Lden). We used multiple linear regression models to examine associations of road traffic noise levels in 1999 (1-year mean) with BMI and waist circumference, adjusting for potential confounders, and evaluated effect modification by degree of urbanization, air pollution levels, night shift work, job strain, sedative use, sleep aid use, and family history of obesity. RESULTS: We did not observe associations between road traffic noise (per 10 dB increase in the 1-year mean Lden) and BMI (kg/m2) (ß: 0.00; 95% confidence interval (CI): -0.07, 0.07) or waist circumference (cm) (ß: -0.09; 95% CI: -0.31, 0.31) in the fully adjusted model. We found significant effect modification of job strain and degree of urbanization on the associations between Lden and both BMI and waist circumference. Job strained nurses were associated with a 0.41 BMI-point increase, (95% CI: 0.06, 0.76) and a 1.00 cm increase in waist circumference (95% CI: 0.00, 2.00). Nurses living in urban areas had a statistically significant positive association of Lden with BMI (ß: 0.26; 95% CI: 0.11, 0.42), whilst no association was found for nurses living in suburban and rural areas. CONCLUSION: Our results suggest that road traffic noise exposure in nurses with particular susceptibilities, such as those with job strain, or living in urban areas, may lead to increased BMI, a marker of adiposity.

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.