Breastfeeding and Endometrial Cancer Risk: An Analysis from the Epidemiology of Endometrial Cancer Consortium

OBJECTIVE: To investigate the association between breastfeeding and endometrial cancer risk using pooled data from 17 studies participating in the Epidemiology of Endometrial Cancer Consortium. METHODS: We conducted a meta-analysis with individuallevel data from three cohort and 14 case-control studies. Study-specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for the association between breastfeeding and risk of endometrial cancer using multivariable logistic regression and pooled using random-effects meta-analysis. We investigated between-study heterogeneity with I2 and Q statistics and metaregression. RESULTS: After excluding nulliparous women, the analyses included 8,981 women with endometrial cancer and 17,241 women in a control group. Ever breastfeeding was associated with an 11% reduction in risk of endometrial cancer (pooled OR 0.89, 95% CI 0.81-0.98). Longer average duration of breastfeeding per child was associated with lower risk of endometrial cancer, although there appeared to be some leveling of this effect beyond 6-9 months. The association with ever breastfeeding was not explained by greater parity and did not vary notably by body mass index or histologic subtype (grouped as endometrioid and mucinous compared with serous and clear cell). CONCLUSION: Our findings suggest that reducing endometrial cancer risk can be added to the list of maternal benefits associated with breastfeeding. Ongoing promotion, support, and facilitation of this safe and beneficial behavior might therefore contribute to the prevention of this increasingly common cancer

Circulating levels of inflammation and the effect on exercise-related changes in bone mass, structure and strength in middle-aged and older men

Chronic, low-grade systematic inflammation has been associated with bone loss and increased fracture risk. We previously reported that exercise improved femoral neck bone mineral density (BMD), geometry and strength and lumbar spine trabecular BMD in middle-aged and older men, but had no effect on markers of inflammation. The aim of this study was to examine the association between basal inflammatory status and the adaptive skeletal responses to exercise. Secondary analysis was completed on 91 men aged 50–79 years who participated in an 18-month program of progressive resistance training plus weight-bearing impact exercise (3 day/week) with and without additional calcium–vitamin D 3 . Markers of inflammation (serum hs-CRP, TNF-α and IL-6) and DXA and QCT-derived BMD, bone structure and strength at the lumbar spine and proximal femur were measured at baseline and 18 months. Multiple regression was used to assess associations between skeletal changes and both baseline levels of individual inflammatory markers and a composite inflammatory index derived from the number of markers categorized into the highest tertile. Baseline serum hs-CRP, TNFα and IL-6 and the composite inflammatory index score were not associated with skeletal changes at any site after adjusting for age, change in lean mass, disease(s)/medication use and adherence to the exercise intervention. In conclusion, this study indicates that basal inflammatory status does not influence the osteogenic response to exercise training in healthy middle-aged and older men. </p

Pregnancy outcomes and risk of endometrial cancer: A pooled analysis of individual participant data in the Epidemiology of Endometrial Cancer Consortium

A full-term pregnancy is associated with reduced endometrial cancer risk; however, whether the effect of additional pregnancies is independent of age at last pregnancy is unknown. The associations between other pregnancy-related factors and endometrial cancer risk are less clear. We pooled individual participant data from 11 cohort and 19 case-control studies participating in the Epidemiology of Endometrial Cancer Consortium (E2C2) including 16 986 women with endometrial cancer and 39 538 control women. We used one- and two-stage meta-analytic approaches to estimate pooled odds ratios (ORs) for the association between exposures and endometrial cancer risk. Ever having a full-term pregnancy was associated with a 41% reduction in risk of endometrial cancer compared to never having a full-term pregnancy (OR = 0.59, 95% confidence interval [CI] 0.56-0.63). The risk reduction appeared the greatest for the first full-term pregnancy (OR = 0.78, 95% CI 0.72-0.84), with a further ~15% reduction per pregnancy up to eight pregnancies (OR = 0.20, 95% CI 0.14-0.28) that was independent of age at last full-term pregnancy. Incomplete pregnancy was also associated with decreased endometrial cancer risk (7%-9% reduction per pregnancy). Twin births appeared to have the same effect as singleton pregnancies. Our pooled analysis shows that, while the magnitude of the risk reduction is greater for a full-term pregnancy than an incomplete pregnancy, each additional pregnancy is associated with further reduction in endometrial cancer risk, independent of age at last full-term pregnancy. These results suggest that the very high progesterone level in the last trimester of pregnancy is not the sole explanation for the protective effect of pregnancy