BMI and breast cancer risk around age at menopause

BACKGROUND

A high body mass index (BMI, kg/m2) is associated with decreased risk of breast cancer before menopause, but increased risk after menopause. Exactly when this reversal occurs in relation to menopause is unclear. Locating that change point could provide insight into the role of adiposity in breast cancer etiology.

METHODS

We examined the association between BMI and breast cancer risk in the Premenopausal Breast Cancer Collaborative Group, from age 45 up to breast cancer diagnosis, loss to follow-up, death, or age 55, whichever came first. Analyses included 609,880 women in 16 prospective studies, including 9956 who developed breast cancer before age 55. We fitted three BMI hazard ratio (HR) models over age-time: constant, linear, or nonlinear (via splines), applying piecewise exponential additive mixed models, with age as the primary time scale. We divided person-time into four strata: premenopause; postmenopause due to natural menopause; postmenopause because of interventional loss of ovarian function (bilateral oophorectomy (BO) or chemotherapy); postmenopause due to hysterectomy without BO. Sensitivity analyses included stratifying by BMI in young adulthood, or excluding women using menopausal hormone therapy.

RESULTS

The constant BMI HR model provided the best fit for all four menopausal status groups. Under this model, the estimated association between a five-unit increment in BMI and breast cancer risk was HR=0.87 (95% CI: 0.85, 0.89) before menopause, HR=1.00 (95% CI: 0.96, 1.04) after natural menopause, HR=0.99 (95% CI: 0.93, 1.05) after interventional loss of ovarian function, and HR=0.88 (95% CI: 0.76, 1.02) after hysterectomy without BO.

CONCLUSION

The BMI breast cancer HRs remained less than or near one during the 45-55 year age range indicating that the transition to a positive association between BMI and risk occurs after age 55.

Multicentre, population-based, case-control study of particulates, combustion products and amyotrophic lateral sclerosis risk

OBJECTIVE

To investigate whether exposure to particulates and combustion products may explain the association between certain occupations and amyotrophic lateral sclerosis (ALS) risk in a large, multicentre, population-based, case-control study, based on full job histories, using job-exposure matrices, with detailed information on possible confounders.

METHODS

Population-based patients with ALS and controls were recruited from five registries in the Netherlands, Ireland and Italy. Demographics and data regarding educational level, smoking, alcohol habits and lifetime occupational history were obtained using a validated questionnaire. Using job-exposure matrices, we assessed occupational exposure to silica, asbestos, organic dust, contact with animals or fresh animal products, endotoxins, polycyclic aromatic hydrocarbons and diesel motor exhaust. Multivariate logistic regression models adjusting for confounding factors were used to determine the association between these exposures and ALS risk.

RESULTS

We included 1557 patients and 2922 controls. Associations were positive for all seven occupational exposures (ORs ranging from 1.13 to 1.73 for high vs never exposed), and significant on the continuous scale for silica, organic dust and diesel motor exhaust (p values for trend ≤0.03). Additional analyses, adding an exposure (one at a time) to the model in the single exposure analysis, revealed a stable OR for silica. We found similar results when patients with a C9orf72 mutation were excluded.

CONCLUSION

In a large, multicentre study, using harmonised methodology to objectively quantify occupational exposure to particulates and combustion products, we found an association between ALS risk and exposure to silica, independent of the other occupational exposures studied.

General and abdominal adiposity and the risk of Parkinson's disease: A prospective cohort study

INTRODUCTION

Due to demographic change, an increase in the frequency of Parkinson's disease (PD) patients is expected in the future and, thus, the identification of modifiable risk factors is urgently needed. We aimed to examine the associations of body mass index (BMI) and waist circumference (WC) with incident PD.

METHODS

In 13 of the 23 centers of the European Prospective Investigation into Cancer and Nutrition (EPIC) study, a total of 734 incident cases of PD were identified between 1992 and 2012 with a mean follow-up of 12 years. Cox proportional hazards regression was used to calculate hazard ratios (HR) with 95% confidence intervals (CI). We modelled anthropometric variables as continuous and categorical exposures and performed subgroup analyses by potential effect modifiers including sex and smoking.

RESULTS

We found no association between BMI, WC and incident PD, neither among men nor among women. Among never and former smokers, BMI and waist circumference were also not associated with PD risk. For male smokers, however, we observed a statistically significant inverse association between BMI and PD risk (HR 0.51, 95%CI: 0.30, 0.84) and the opposite for women, i.e. a significant direct association of BMI (HR 1.79, 95%CI: 1.04, 3.08) and waist circumference (HR 1.64, 95%CI: 1.03, 2.61) with risk of PD.

CONCLUSION

Our data revealed no association between excess weight and PD risk but a possible interaction between anthropometry, sex and smoking.

[Associations of short-term evaluation assessments and patient characteristics with the use of coercive measures]

BACKGROUND

Dutch mental health care institutes are currently making a tremendous effort to reduce the number of coercive measures they impose, such as seclusion. Despite this effort, a group of patients are still being subjected to enforced medication or seclusion.

AIM

To obtain more knowledge about which patient characteristics are associated with coercive measures and thereby to identify signs that could be acted upon at an earlier stage to prevent deterioration of the patient's condition and reduce the need for coercive measures.

METHOD

We performed a prospective, naturalistic three-month study involving patients in two acute psychiatric admission wards. To collect the data we required, we used two short-term risk-assessment instruments: the Brøset Violence Checklist (BVC) and the Kennedy Axis V (KA-V). By means of statistical analyses we investigated which patient characteristics were associated with the use of coercive measures.

RESULTS

Of the 179 patients, 52 patients (29%) were subjected to a coercive measure during the admission procedure. The following patient characteristics were found to be associated with coercive measures: a bipolar disorder, involuntarily admission, display of physical violence just before admission, scores on the BVC and the KA-V items assessing 'social skills' and 'violence'. The two BVC items 'attacks on objects' and 'display of physical violence just before admission' were the ones most strongly associated with seclusion.

CONCLUSION

Although the sensitivity of the regression model was modest, the associated patient characteristics, combined with the two short-term risk assessment scores, may be helpful for identifying at an early stage those patients who run a high risk of being subjected to coercive measures.

Impact of occupational carcinogens on lung cancer risk in a general population

BACKGROUND

Exposure to occupational carcinogens is an important preventable cause of lung cancer. Most of the previous studies were in highly exposed industrial cohorts. Our aim was to quantify lung cancer burden attributable to occupational carcinogens in a general population.

METHODS

We applied a new job-exposure matrix (JEM) to translate lifetime work histories, collected by personal interview and coded into standard job titles, into never, low and high exposure levels for six known/suspected occupational lung carcinogens in the Environment and Genetics in Lung cancer Etiology (EAGLE) population-based case-control study, conducted in Lombardy region, Italy, in 2002-05. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in men (1537 cases and 1617 controls), by logistic regression adjusted for potential confounders, including smoking and co-exposure to JEM carcinogens. The population attributable fraction (PAF) was estimated as impact measure.

RESULTS

Men showed an increased lung cancer risk even at low exposure to asbestos (OR: 1.76; 95% CI: 1.42-2.18), crystalline silica (OR: 1.31; 95% CI: 1.00-1.71) and nickel-chromium (OR: 1.18; 95% CI: 0.90-1.53); risk increased with exposure level. For polycyclic aromatic hydrocarbons, an increased risk (OR: 1.64; 95% CI: 0.99-2.70) was found only for high exposures. The PAFs for any exposure to asbestos, silica and nickel-chromium were 18.1, 5.7 and 7.0%, respectively, equivalent to an overall PAF of 22.5% (95% CI: 14.1-30.0). This corresponds to about 1016 (95% CI: 637-1355) male lung cancer cases/year in Lombardy.

CONCLUSIONS

These findings support the substantial role of selected occupational carcinogens on lung cancer burden, even at low exposures, in a general population.

Limits on the cosmological abundance of supermassive compact objects from a search for multiple imaging in compact radio sources

Using very long baseline interferometry we have searched a sample of 300 compact radio sources for examples of multiple imaging produced by gravitational lensing; no multiple images were found with separations in the angular range 1.5--50 milliarcsec. This null result allows us to place a limit on the cosmological abundance of intergalactic supermassive compact objects in the mass range approximately 10(6)M( middle dot in circle) to approximately 10(8)M( middle dot in circle); such objects cannot make up more than approximately 1% of the closure density ( 95% confidence). A uniformly distributed population of supermassive black holes forming soon after the big bang does not, therefore, contribute significantly to the dark matter content of the Universe.

H i Absorption in the Steep-Spectrum Superluminal Quasar 3C 216

The search for H i absorption in strong compact steep-spectrum sources is a natural way to probe the neutral gas contents in young radio sources. In turn, this may provide information about the evolution of powerful radio sources. The recently improved capabilities of the Westerbork Synthesis Radio Telescope have made it possible to detect a 0.31% (19 mJy) deep neutral atomic hydrogen absorption line associated with the steep-spectrum superluminal quasar 3C 216. The redshift (z=0.67) of the source shifts the frequency of the 21 cm line down to the ultra-high-frequency (UHF) band (850 MHz). The exact location of the H i-absorbing gas remains to be determined by spectral line VLBI observations at 850 MHz. We cannot exclude that the gas might be extended on galactic scales, but we think it is more likely to be located in the central kiloparsec. Constraints from the lack of X-ray absorption probably rule out obscuration of the core region, and we argue that the most plausible site for the H i absorption is in the jet-cloud interaction observed in this source.

Superluminal sources

Predictions for the apparent velocity statistics under simple beaming models are presented and compared to the observations. The potential applications for tests of unification models and for cosmology (source counts, measurements of the Hubble constant H0 and the deceleration parameter q0) are discussed. First results from a large homogeneous survey are presented. The data do not show compelling evidence for the existence of intrinsically different populations of galaxies, BL Lacertae objects, or quasars. Apparent velocities betaapp in the range 1-5 h-1, where h = H0/100 km.s-1.Mpc-1 [1 megaparsec (Mpc) = 3.09 x 10(22) m], occur with roughly equal frequency; higher values, up to betaapp = 10 h-1, are rather more scarce than appeared to be the case from earlier work, which evidently concentrated on sources that are not representative of the general population. The betaapp distribution suggests that there might be a skewed distribution of Lorentz factors over the sample, with a peak at gammab approximately 2 h-1 and a tail up to at least gammab approximately 10 h-1. There appears to be a clearly rising upper envelope to the betaapp distribution when plotted as a function of observed 5-GHz luminosity; a combination of source counts and the apparent velocity statistics in a larger sample could provide much insight into the properties of radio jet sources.

Structure and evolution of the compact radio source in NGC 1275

Investigations of the fine-scale structure in the compact nucleus of the radio source 3C 84 in NGC 1275 (New General Catalogue number) are reported. Structural monitoring observations beginning as early as 1976, and continuing to the present, revealed subluminal motions in a jet-like relatively diffuse region extending away from a flat-spectrum core. A counterjet feature was discovered in 1993, and very recent nearly simultaneous studies have detected the same feature at five frequencies ranging from 5 to 43 GHz. The counterjet exhibits a strong low-frequency cutoff, giving this region of the source an inverted spectrum. The observations are consistent with a physical model in which the cutoff arises from free-free absorption in a volume that surrounds the core but obscures only the counterjet feature. If such a model is confirmed, very-long-baseline radio interferometry observations can then be used to probe the accretion region, outside the radio jet, on parsec scales.

Bidirectional motion observed in the compact symmetric object 1946+708

We present the first direct measurements of bidirectional motions in an extragalactic radio jet. The radio source 1946+708 is a compact symmetric object with striking S-symmetry identified with a galaxy at a redshift of 0.101. From observations 2 years apart we have determined the velocities of four compact components in the jet, the fastest of which has an apparent velocity of 1.09 h-1c. By pairing up the components, assuming they were simultaneously ejected in opposite directions, we derive a 1 lower limit on the Hubble constant, H0 > 42 km.s-1.Mpc-1.

An anatomic basis for ultrasound images of the human placenta

Placentas after uneventful pregnancies were perfused under physiologic pressure in the fetal vessels, expanded to their predelivery volume, fixated with 4% formaldehyde, and compared to their ultrasound images in pregnancy. The placentas showed a side arrangement of the fetal cotyledons in contact with the basal plate. The centers of the cotyledons showed an empty space in which the spiral arteries ended. These spaces in the placenta corresponded with transsonic areas of ultrasound. The central spaces were surrounded by a relatively dense shell of villi containing the more or less fibrotic stem villi. This explained the areas of increased echo-density, as seen by ultrasound during the last trimester of pregnancy. The fetal cotyledons, composed of a central cavity and a dense villous shell, were separated by a reticular area. The veins ended at the basal plate in these intercotyledonary areas.