Since high energy intake, inactivity, hypertension and diabetes are linked to obesity and an unfavorable hormonal profile, we wanted to test whether energy intake, physical activity, blood pressure and serum glucose are related to the risk of endometrial cancer independent of the body mass index (BMI The wide differences in incidence of endometrial cancer (type I-carcinoma) across countries and between urban and rural populations, as well as the changing disease incidence in migrants, indicate that environmental factors have a huge influence on the occurrence of the disease. 1 The etiology of endometrial cancer is unknown, yet it has been shown that malignant transformation, cancer cell proliferation, tumor invasion and tumor progression are enhanced by deficiency in progesterone and its action relative to estrogen in the glandular cells of the endometrium. 2,3 A shift in energy balance (e.g., excessive energy intake relative to energy expenditure) might contribute to an unfavorable sex hormone profile in women. 2,4 Epidemiological studies on the association between energy intake and the risk of endometrial cancer are inconclusive. 5-10 A chronically excessive intake of energy relative to requirements may lead to increased body weight. Although adult obesity has consistently been associated with an increased risk of endometrial cancer, the effect may be age and menopausal status dependent. 11 The energy expended during physical activity may represent between 15 and 50% of total energy expenditure, depending on the amount of physical activity performed and the body mass. 12 Epidemiological studies find that inactivity may be associated with an increased endometrial cancer risk. [13][14][15][16][17][18] However, some studies indicate that the effect may be dependent on type of activity (i.e., during work and recreation). 19,20 We have previously reported on the effect of activity, energy intake and accurately measured body mass on the incidence of breast cancer 21 and similar studies on endometrial cancer are needed. 11 Body mass and endogenous levels of estrogens have been associated with risk independently of each other, 22,23 suggesting that the unopposed estrogen/relative progesterone deficiency hypothesis is insufficient to explain endometrial cancer. It has been hypothesized that insulin, a growth factor known for its mitogenic activity, 24,25 plays a major role in endometrial carcinogenesis. Hypertension and diabetes are markers of insulin resistance/hyperinsulinemia. 26,27 Observations linking blood pressure, glucose metabolism and markers of insulin resistance to endometrial cancer come mostly from retrospective studies, which have provided less conclusive results because of self-reported disease history and anthropometry or an absence of adjustment for body mass. 1 We analyzed data that included repeated assessments of variables from a cohort of 24,460 Norwegian women to elucidate whether energy intake, recreational and occupational activity, blood pressure and serum glucose concentration are associated ...

The Tromsø physical activity questionnaire has acceptable validity and provides valid estimates of high-intensity leisure activity. However, these results underscore the need for collecting objectively PA measurements in large epidemiological studies.

Metabolic components [body mass index (BMI), blood pressure, serum lipids] and physical activity may affect biological mechanisms of importance for breast cancer prognosis. A population-based survival study among 1,364 breast cancer cases within the Norwegian Counties Study during 1974-2005 was conducted. Pre-diagnostic measurements of BMI, blood pressure, serum lipids, and self-reported physical activity were assessed. Multivariable Cox proportional hazard models were used in analyses (SAS version 9.11). Among these breast cancer cases (age at diagnosis 27-79 years), 429 women died (8.2 mean follow-up years). Those with a BMI >or= 30 kg/m(2) had a 1.47 higher risk of dying during follow-up than women with a BMI of 18.5-25 kg/m(2) [hazard ratio (HR) = 1.47, 95% CI 1.08-1.99]. Women with BMI < 25 kg/m(2) and age of diagnosis >or=55 years had a 66% reduction in overall mortality if they regularly exercised before diagnosis compared with sedentary women (HR = 0.34, 95% CI 0.16-0.71). Women in the highest tertile of total cholesterol had a 29% increase in mortality compared to women in the lowest tertile (HR = 1.29, 95% CI 1.01-1.64). Additionally, women in the highest tertile of blood pressure had a 41% increase in mortality compared to women in the lowest tertile of blood pressure (HR = 1.41, 95% CI 1.09-1.83). Our study supports a relationship between mortality not only in relation to BMI, but also blood pressure, lipids, and physical activity among breast cancer patients. These factors may all be important targets for invention among breast cancer patients.