Breast-cancer incidence in relation to height,weight and body-fat distribution in the Dutch “DOM” cohort

In a cohort of 11,663 participants in a breast-cancer screening program, height, weight, waist circumference and hip circumference were measured, and information about menstrual and reproductive history was obtained by questionnaire. After exclusion of 83 women with unclear menopausal status, the subjects were divided into 3 sub-cohorts: 5,891 women who were pre-menopausal at the time of data collection, 3,521 women who had entered the study after natural menopause, and 2068 women who had been hysterectomized and/or ovariectomized. After a median follow-up of 10.6 years, 147, 76 and 52 incident cases of breast cancer were detected in the 3 respective sub-cohorts. No statistically significant association was found in any of the sub-cohorts between breast-cancer risk and height, weight, body-mass index (BMI) or hip circumference. In the sub-cohort of women with natural menopause, however, risk of breast cancer was positively and significantly associated with the ratio of waist-to-hip circumferences (WHR) (RR = 2.63 for upper vs. lower quartile), and this association did not change after adjustment for variations in disease risk related to body height and weight. Although similar to observations in other cohort studies showing positive associations between obesity and breast-cancer risk in post-menopausal women, our results are different, in that WHR and not BMI appears to be the more specific indicator of breast-cancer risk. Int. J. Cancer 76:647–651, 1998.© 1998 Wiley-Liss, Inc.     

Anthropometric factors and risk of endometrial cancer: the European prospective investigation into cancer and nutrition

Objective To examine the association between anthropometry and endometrial cancer, particularly by menopausal status and exogenous hormone use subgroups. Methods Among 223,008 women in the European Prospective Investigation into Cancer and Nutrition (EPIC) study, there were 567 incident endometrial cancer cases during 6.4 years of follow-up. The analysis was performed with Cox proportional hazards modeling. Results Weight, body mass index (BMI), waist and hip circumferences and waist–hip ratio (WHR) were strongly associated with increased risk of endometrial cancer. The relative risk (RR) for obese (BMI 30– < 40 kg/m²) compared to normal weight (BMI < 25) women was 1.78, 95% CI = 1.41–2.26, and for morbidly obese women (BMI ≥ 40) was 3.02, 95% CI = 1.66–5.52. The RR for women with a waist circumference of ≥88 cm vs. <80 cm was 1.76, 95% CI = 1.42–2.19. Adult weight gain of ≥20 kg compared with stable weight (±3 kg) increased risk independent of body weight at age 20 (RR = 1.75, 95% CI = 1.11–2.77). These associations were generally stronger for postmenopausal than premenopausal women, and oral contraceptives never-users than ever-users, and much stronger among never-users of hormone replacement therapy compared to ever-users. Conclusion Obesity, abdominal adiposity, and adult weight gain were strongly associated with endometrial cancer risk. These associations were particularly evident among never-users of hormone replacement therapy.     

Environmental contaminants and body fat distribution.

The effect of body mass index (BMI) and waist:hip ratio (WHR) on plasma levels of organochlorines [i.e., 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE)] was investigated in a sample of black and white women drawn from a population-based study in North Carolina. Organochlorine levels were determined in plasma samples from 99 women selected on the basis of race (black versus white) and quartile of the WHR (1st versus 4th). Of a panel of 20 organochlorine compounds tested, only DDE was detectable in most study subjects. Measurements of height, weight, and waist and hip circumferences were taken during an in-person interview. Information was elicited regarding dietary, residential, and breast-feeding histories. Results of multiple regression analyses indicate that black women had significantly higher plasma levels of DDE than white women. These levels were independent of BMI and WHR. BMI but not WHR was also found to be an independent predictor of DDE plasma level. These results suggest that black/white differences should be considered in studies that explore the relationship between environmental contaminants and various disease outcomes, such as breast cancer risk. In addition, BMI may affect circulating levels of contaminants and should also be considered a potentially important modifying factor for exposure to lipophilic substances.     

A prospective Swedish study on body size, body composition, diabetes, and prostate cancer risk

Obesity may be associated with increased risk of prostate cancer (PCa). According to one hypothesis, obesity could lower the risk of non-aggressive tumours, while simultaneously increasing the risk of aggressive cancer. Furthermore, central adiposity may be independently associated with PCa risk; it is also associated with diabetes, which itself may influence risk of PCa. We studied the associations between height, body composition, and fat distribution, diabetes prevalence and risk of total, aggressive, and non-aggressive PCa in 10 564 initially cancer-free men (aged 45–73 years) of the population-based Malmö Diet and Cancer cohort. Anthropometric and body composition measurements, including bioelectrical impedance for estimation of fat mass, were performed by study nurses. Diabetes prevalence was self-reported. Cancer cases and clinical characteristics were ascertained through national and regional registry data. Dietary and other background data were obtained through a modified diet history method and an extensive questionnaire. During a mean follow-up of 11.0 years, 817 incidental PCa cases were diagnosed. Of these, 281 were classified as aggressive. There were 202 cases occurring before 65 years of age. Height was positively associated with total and non-aggressive PCa risk. Waist–hip ratio (WHR), a measure of central adiposity, was positively associated with PCa before age 65, and less strongly, with total PCa. This association was independent of body mass index (BMI) and other potential confounders. General adiposity, expressed as BMI or body fat percentage, and prevalent diabetes were not associated with PCa risk. In this study, WHR and body height were stronger PCa predictors than general adiposity.     

High levels of circulating insulin-like growth factor-I increase prostate cancer risk: a prospective study in a population-based nonscreened cohort.

PURPOSE: Insulin-like growth factor-I (IGF-I) stimulates proliferation and inhibits apoptosis in prostate cancer cells, and IGF-I has been associated with increased prostate cancer risk in some, but not all, epidemiologic studies. SUBJECTS AND METHODS: We extended our previous case-control study nested in the Northern Sweden Health and Disease Cohort, a population-based cohort from a region where little prostate specific antigen (PSA) screening is done. Levels of IGF-I and IGF binding protein-3 (IGFBP-3) were measured in prediagnostic blood samples from a total of 281 men who were subsequently diagnosed with prostate cancer after recruitment (median, 5 years after blood collection) and from 560 matched controls. RESULTS: Logistic regression analyses showed increases in prostate cancer risk with increasing plasma peptide levels, up to an odds ratio (OR) for top versus bottom quartile of IGF-I of 1.67 (95% CI, 1.02 to 2.71; Ptrend = .05), which was attenuated after adjustment for IGFBP-3 to an OR of 1.47 (95% CI, 0.81 to 2.64; P (trend) =.32). For men younger than 59 years at recruitment, OR for top versus bottom quartile of IGF-I was 4.12 (95% CI, 1.01 to 16.70; Ptrend = .002), which was significantly stronger than for men older than 59 years (P (interaction) = .006). For men with advanced cancer, OR for top versus bottom quartile of IGF-I was 2.87 (95% CI, 1.01 to 8.12; Ptrend = .10). CONCLUSION: Our data add further support for IGF-I as an etiologic factor in prostate cancer and indicate that circulating IGF-I levels measured at a comparatively young age may be most strongly associated with prostate cancer risk.     

Body size and breast cancer risk: findings from the European Prospective Investigation into Cancer And Nutrition (EPIC)

The evidence for anthropometric factors influencing breast cancer risk is accumulating, but uncertainties remain concerning the role of fat distribution and potential effect modifiers. We used data from 73,542 premenopausal and 103,344 postmenopausal women from 9 European countries, taking part in the EPIC study. RRs from Cox regression models were calculated, using measured height, weight, BMI and waist and hip circumferences; categorized by cohort-wide quintiles; and expressed as continuous variables, adjusted for study center, age and other risk factors. During 4.7 years of follow-up, 1,879 incident invasive breast cancers were identified. In postmenopausal women, current HRT modified the body size-breast cancer association. Among nonusers, weight, BMI and hip circumference were positively associated with breast cancer risk (all ptrend < or = 0.002); obese women (BMI > 30) had a 31% excess risk compared to women with BMI < 25. Among HRT users, body measures were inversely but nonsignificantly associated with breast cancer. Excess breast cancer risk with HRT was particularly evident among lean women. Pooled RRs per height increment of 5 cm were 1.05 (95% CI 1.00-1.16) in premenopausal and 1.10 (95% CI 1.05-1.16) in postmenopausal women. Among premenopausal women, hip circumference was the only other measure significantly related to breast cancer (ptrend = 0.03), after accounting for BMI. In postmenopausal women not taking exogenous hormones, general obesity is a significant predictor of breast cancer, while abdominal fat assessed as waist-hip ratio or waist circumference was not related to excess risk when adjusted for BMI. Among premenopausal women, weight and BMI showed nonsignificant inverse associations with breast cancer.     

Anthropometric measures, endogenous sex steroids and breast cancer risk in postmenopausal women: a study within the EPIC cohort

In a large case-control study on breast cancer risk and serum hormone concentrations, nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we examined to what extent the relationship of excess body weight with breast cancer risk may be explained by changes in sex steroids. Height, weight, waist and hip circumferences, and serum measurements of testosterone [T], androstenedione [Delta4], dehydroepiandrosterone sulphate [DHEAS], estradiol [E2], estrone [E1] and sex-hormone binding globulin [SHBG] were available for 613 breast cancer cases, and 1,139 matched controls, who were all menopausal at the time of blood donation. Free T [fT] and free E2 [fE2] were calculated using mass action equations. Breast cancer risk was related to body mass index (BMI) (RR = 1.11 [0.99-1.25], per 5 kg/m2 increase in BMI), and waist (RR = 1.12 [1.02-1.24], per 10 cm increase) and hip circumferences (RR = 1.14 [1.02-1.27], per 10 cm increase). The increase in breast cancer risk associated with adiposity was substantially reduced after adjustment for any estrogens, especially for fE2 (from 1.11 [0.99-1.25] to 0.99 [0.87-1.12], from 1.12 [1.02-1.24] to 1.02 [0.92-1.14] and from 1.14 [1.02-1.27] to 1.05 [0.93-1.18] for BMI, waist and hip circumferences, respectively). A modest attenuation in excess risk was observed after adjustment for fT, but the remaining androgens had little effect on the association of body adiposity with breast cancer. Our data indicate that the relationship of adiposity with breast cancer in postmenopausal women could be partially explained by the increases in endogenous estrogens, and by a decrease in levels of SHBG.     

Comparison of anthropometric measures as predictors of cancer incidence: A pooled collaborative analysis of 11 Australian cohorts

Obesity is a risk factor for cancer. However, it is not known if general adiposity, as measured by body mass index (BMI) or central adiposity [e.g., waist circumference (WC)] have stronger associations with cancer, or which anthropometric measure best predicts cancer risk. We included 79,458 men and women from the Australian and New Zealand Diabetes and Cancer Collaboration with complete data on anthropometry [BMI, WC, Hip Circumference (HC), WHR, waist to height ratio (WtHR), A Body Shape Index (ABSI)], linked to the Australian Cancer Database. Cox proportional hazards models assessed the association between each anthropometric marker, per standard deviation and the risk of overall, colorectal, post‐menopausal (PM) breast, prostate and obesity‐related cancers. We assessed the discriminative ability of models using Harrell's c‐statistic. All anthropometric markers were associated with overall, colorectal and obesity‐related cancers. BMI, WC and HC were associated with PM breast cancer and no significant associations were seen for prostate cancer. Strongest associations were observed for WC across all outcomes, excluding PM breast cancer for which HC was strongest. WC had greater discrimination compared to BMI for overall and colorectal cancer in men and women with c‐statistics ranging from 0.70 to 0.71. We show all anthropometric measures are associated with the overall, colorectal, PM breast and obesity‐related cancer in men and women, but not prostate cancer. WC discriminated marginally better than BMI. However, all anthropometric measures were similarly moderately predictive of cancer risk. We do not recommend one anthropometric marker over another for assessing an individuals' risk of cancer.     

Body size and risk of prostate cancer in Jamaican men

We investigated the associations between body size and risk of prostate cancer in a hospital-based case–control study in Jamaica. Height, weight, waist, and hip circumference were measured at enrollment, and data collected on medical and lifestyle factors for newly diagnosed cases (n = 243) and controls (n = 275). Compared with men in the normal range of waist-hip ratio (WHR), men with WHR ≥0.95 were at greater risk of total prostate cancer (OR,1.72; CI, 1.01–3.00) and high-grade cancer (OR, 2.02; CI, 1.03–3.96). With additional control for BMI, the association with WHR remained significant for total prostate cancer (OR, 1.90; CI, 1.01–3.53) and high-grade disease (OR, 2.94; CI, 1.34–6.38). There was no association between waist circumference and cancer without control for BMI but after controlling for BMI, waist circumference >90 cm (OR, 2.45; CI, 1.01–5.94) and >102 cm (OR, 5.57; CI, 1.43–18.63) showed a dose–response relationship with high-grade disease. Height and BMI were not associated with risk of prostate cancer. Abdominal obesity may be associated with risk of high-grade prostate cancer. Risk may be greater in those with higher abdominal obesity relative to overall size. The results further highlight the importance of investigating relationships by characteristics of the tumor.     

A pooled analysis of 14 cohort studies of anthropometric factors and pancreatic cancer risk

Epidemiologic studies of pancreatic cancer risk have reported null or nonsignificant positive associations for obesity, while associations for height have been null. Waist and hip circumference have been evaluated infrequently. A pooled analysis of 14 cohort studies on 846,340 individuals was conducted; 2,135 individuals were diagnosed with pancreatic cancer during follow-up. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox proportional hazards models, and then pooled using a random effects model. Compared to individuals with a body mass index (BMI) at baseline between 21-22.9 kg/m(2) , pancreatic cancer risk was 47% higher (95%CI:23-75%) among obese (BMI ≥ 30 kg/m(2) ) individuals. A positive association was observed for BMI in early adulthood (pooled multivariate [MV]RR = 1.30, 95%CI = 1.09-1.56 comparing BMI ≥ 25 kg/m(2) to a BMI between 21 and 22.9 kg/m(2) ). Compared to individuals who were not overweight in early adulthood (BMI < 25 kg/m(2) ) and not obese at baseline (BMI < 30 kg/m(2) ), pancreatic cancer risk was 54% higher (95%CI = 24-93%) for those who were overweight in early adulthood and obese at baseline. We observed a 40% higher risk among individuals who had gained BMI ≥ 10 kg/m(2) between BMI at baseline and younger ages compared to individuals whose BMI remained stable. Results were either similar or slightly stronger among never smokers. A positive association was observed between waist to hip ratio (WHR) and pancreatic cancer risk (pooled MVRR = 1.35 comparing the highest versus lowest quartile, 95%CI = 1.03-1.78). BMI and WHR were positively associated with pancreatic cancer risk. Maintaining normal body weight may offer a feasible approach to reducing morbidity and mortality from pancreatic cancer.     

Anthropometric Measurements and Epithelial Ovarian Cancer Risk in African–American and White women

Previous studies of anthropometric factors and ovarian cancer risk have been inconsistent and none have evaluated the association among African–American women. Data from a population-based, case–control study of 593 cases and 628 controls were used to evaluate ovarian cancer risk in relation to weight, height, body mass index (BMI) and waist-to-hip ratio (WHR). Odds ratios (ORs) and 95% confidence intervals (CIs) were computed and established risk factors were adjusted for using logistic regression models, stratified by race. Among all races, weight at age 18, WHR, weight and BMI one year prior to interview were associated with elevated ovarian cancer risk. When stratified by race, the association between WHR and ovarian was similar among Whites and among African Americans. However, African–American women in the fourth quartile of height had an elevated risk of ovarian cancer (OR = 3.2; 95% CI = 1.3–7.8), but this risk was not apparent in Whites (OR = 1.0; 95% CI␣ = 0.7–1.4). These findings support the hypothesis that obesity is an important risk factor of ovarian cancer among African–Americans and Whites and also suggest that height may be a risk factor specific to African–Americans.^★ This work was performed at the Duke University Comprehensive Cancer, Durham, NC, USA.     

Prediagnostic body size and breast cancer survival in the E3N cohort study

Obesity has been associated with poor breast cancer prognosis, however most studies have focused on body mass index (BMI) and few have considered the distribution of adipose tissue. We investigated associations between prediagnostic adiposity and breast cancer survival, considering BMI, waist and hip circumferences (WC and HC), and waist‐to‐hip ratio (WHR). Analyses included 3,006 women from the French E3N prospective cohort study diagnosed with primary invasive breast cancer between 1995 and 2008. We investigated overall, breast cancer‐specific, and disease‐free survival, overall and according to stage, menopausal and hormonal status and year of diagnosis, using Cox proportional hazard models adjusted for tumor characteristics and lifestyle risk factors. Women with a prediagnostic HC > 100 cm were at increased risk of death from all causes (hazard ratio (HR)_{>100vs < 95 cm} = 1.38, 95% Confidence Interval (CI) = 1.02–1.86, P_trend = 0.02) and from breast cancer (HR_{>100vs < 95 cm} = 1.50, CI = 1.03–2.17, P_trend = 0.03), and of second invasive cancer event (HR_{>100vs < 95 cm} = 1.36, CI = 1.11–1.67, P_trend = 0.002), compared to those with HC <95 cm. Associations were stronger after adjustment for BMI. BMI, WC and WHR were not associated with survival after breast cancer. Our study underlines the importance of going beyond BMI when studying the association between adiposity and breast cancer survival. Further studies should be conducted to confirm our results on hip circumference.     

Overall and abdominal obesity and prostate cancer risk in a West African population: An analysis of the Ghana Prostate Study

Obesity has been associated with an increased risk of advanced prostate cancer. However, most studies have been conducted among North American and European populations. Prostate cancer mortality appears elevated in West Africa, yet risk factors for prostate cancer in this region are unknown. We thus examined the relationship between obesity and prostate cancer using a case-control study conducted in Accra, Ghana in 2004 to 2012. Cases and controls were drawn from a population-based sample of 1037 men screened for prostate cancer, yielding 73 cases and 964 controls. An additional 493 incident cases were recruited from the Korle-Bu Teaching Hospital. Anthropometric measurements were taken at enrollment. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR) and prostate cancer, adjusting for potential confounders. The mean BMI was 25.1 kg/m² for cases and 24.3 kg/m² for controls. After adjustment, men with BMI ≥ 30 kg/m² had an increased risk of prostate cancer relative to men with BMI < 25 kg/m² (OR 1.86, 95% CI 1.11-3.13). Elevated WC (OR 1.76, 95% CI 1.24-2.51) and WHR (OR 1.46, 95% CI 0.99-2.16) were also associated with prostate cancer. Associations were not modified by smoking status and were evident for low- and high-grade disease. These findings indicate that overall and abdominal obesity are positively associated with prostate cancer among men in Ghana, implicating obesity as a potentially modifiable risk factor for prostate cancer in this region.     

Body size and colorectal-cancer risk

Individuals whose energy intake exceeds expenditure are at increased risk of colorectal cancer. To determine whether body-size measurements at different ages were risk factors for cancer of the colon-rectum, we carried out a hospital-based case-control study in 6 Italian areas, 2 of which were in the South. Interviews were conducted with 1,217 subjects of both genders with incident histologically confirmed cancer of the colon, 726 with cancer of the rectum, and 4,136 controls hospitalized for acute, non-neoplastic, non-digestive conditions. The questionnaire included information on sociodemographic factors, and physical activity, a validated dietary history, height, weight at diagnosis and at 12, 30 and 50 years of age and waist-to-hip ratio (WHR). After allowance for education, physical activity, energy intake, family history of colorectal cancer and recent change in weight, the body-mass index (BMI) was significantly associated with colorectal-cancer-risk in men (odds ratio, OR, in highest vs. lowest quintile = 1.7; 95% confidence interval, CI, 1.3–2.3), but not in women (corresponding OR = 0.9; 95% CI, 0.7–1.2). Cases of both gender tended to have higher BMI than controls in adolescence, young adulthood and middle age. Height appeared unrelated to risk. In women, but not in men, WHR was positively associated with risk, independently of BMI (OR for ≥0.90 vs. ≤0.81 = 1.6; 95% CI; 1.2–2.1). Thus, excessive weight predicts colorectal-cancer risk in men, whereas abdominal obesity (i.e., a high WHR) represents a more reliable risk indicator in women. Int. J. Cancer 78:161–165, 1998. © 1998 Wiley-Liss, Inc.     

Plasma testosterone and sex hormone-binding globulin concentrations and the risk of prostate cancer among Japanese men: a nested case-control study

Sex hormones, particularly androgens, have been implicated in prostate carcinogenesis. Overall, however, prospective studies have reported no association between circulating levels of sex hormones and the risk of prostate cancer. However, despite the possible difference in the effects of hormones on prostate cancer risk by stage, age, body mass index (BMI) and isoflavones, evidence for these is sparse. Moreover, few studies have been conducted in Asian populations, who are relatively lean and have high isoflavone consumption. We examined the hypothesis that plasma concentrations of circulating testosterone and sex hormone-binding globulin (SHBG) are associated with the risk of prostate cancer in a case-control study nested in the Japan Public Health Center-based Prospective Study. Concentrations of total testosterone and SHBG were measured in plasma samples from 201 patients with prostate cancer and 402 matched control participants, and concentrations of free testosterone were calculated. No overall association between the plasma levels of any hormone and total prostate cancer was observed. Odds ratios (95% confidence interval [CI]) in the highest versus lowest group were 0.71 (95% CI = 0.36-1.41, Ptrend = 0.43) for total testosterone, 0.70 (95% CI = 0.39-1.27, Ptrend = 0.08) for free testosterone and 1.38 (95% CI = 0.69-2.77, Ptrend = 0.23) for SHBG. When stratified by cancer stage, age, BMI and plasma isoflavone level, free testosterone was inversely associated with localized cancers and equol producers, while SHBG was associated with an increased risk of prostate cancer in younger men. In conclusion, in this nested case-control study, concentrations of circulating total testosterone, free testosterone or SHBG were not strongly associated with a risk for total prostate cancer.     

Association of incident carcinoma of the endometrium with body weight and fat distribution in older women: early findings of the Iowa Women's Health Study

Previous epidemiological studies have demonstrated that obesity increases endometrial cancer risk two- to 10-fold. To test the hypothesis that abdominal adiposity further increases this relative risk, we conducted a nested case-control study of endometrial cancer incidence in a cohort of 41,873 women ages 55-69 years. Women were recruited by mail and asked to have a friend measure circumferences of several body parts using a tape measure and written instructions. Two-year follow-up for cancer incidence was conducted using a state-wide cancer registry. Compared to random controls (n = 1,274), cases (n = 63) had higher age-adjusted mean values of waist-to-hip circumference ratio (P = 0.10) and trunk-to-limb circumference ratio (waist plus hip circumferences divided by arm plus calf circumferences, P = 0.008). Other anthropometric variables, including current body mass index and current weight, were also greater (P less than 0.001) in cases than controls. After accounting for the association with body mass index, neither the waist-to-hip ratio nor the trunk-to-limb ratio remained associated with endometrial cancer incidence (P greater than 0.40). A 5 kg/m2 increase in body mass index was associated with an adjusted relative risk of endometrial cancer of 1.80 [95% CI = 1.46, 2.22] when other significant risk factors, namely age, education level, extended use of exogenous estrogens, and age at menopause, were taken into account. We conclude that endometrial cancer risk is increased in relation to the amount but not the distribution of adiposity. This is in contrast with several other diseases in which, in addition to overall body mass, the distribution of adiposity is also important.     

Obesity and the risk of prostate cancer (United States)

The role of obesity in prostate cancer etiology remains controversial. A recent report suggested that obese men younger than age 60 may have a lower risk of developing prostate cancer than men the same age who are not obese. The current study used a nested, matched case–control study design and data collected in the General Practice Research Database between January 1991 and December 2001 to assess the association between body mass index (BMI) and the risk of incident prostate cancer. Seven hundred and thirty cases of prostate cancer with adequate information on BMI were identified and matched to 2740 controls on age, sex, general practice, and index date. Obese men (BMI ≥ 30.0 kilograms [kg]/square of height in meters [m²]) were at lower risk of developing prostate cancer (AOR=0.78, 95% CI: 0.56, 1.09) compared to normal weight men (BMI=23.0–24.9 kg/m²), and the data best fit an inverse quadratic model for the relation between BMI and the risk of prostate cancer. This study provides modest support for a protective association between obesity and the risk of incident prostate cancer.     

Height-related risk factors for prostate cancer

Previous studies have reported that adult height is positively associated with the risk of prostate cancer. The authors carried out a population-based case-control study involving 317 prostate cancer cases and 480 controls to further investigate the possibility that height is more strongly associated with advanced, compared with localized forms of this disease. Since the inherited endocrine factors, which in part determine height attained during the growing years, may influence the risk of familial prostate cancer later in life, the relationship with height was also investigated for familial versus sporadic prostate cancers. Adult height was not related to the risk of localized prostate cancer, but there was a moderate positive association between increasing height and the risk of advanced cancer (relative risk (RR) = 1.62; 95% confidence interval (CI) 0.97-2.73, upper versus lowest quartile, P-trend = 0.07). Height was more strongly associated with the risk of prostate cancer in men with a positive family history compared with those reporting a negative family history. The RR of advanced prostate cancer for men in the upper height quartile with a positive family history was 7.41 (95% CI 1.68-32.67, P-trend = 0.02) compared with a reference group comprised of men in the shortest height quartile with a negative family history. Serum insulin-like growth factor-1 levels did not correlate with height amongst men with familial or sporadic prostate cancers. These findings provide evidence for the existence of growth-related risk factors for prostate cancer, particularly for advanced and familial forms of this disease. The possible existence of inherited mechanisms affecting both somatic and tumour growth deserves further investigation.     

Adult weight gain, fat distribution and mammographic density in Spanish pre- and post-menopausal women (DDM-Spain)

High mammographic density (MD) is a phenotype risk marker for breast cancer. Body mass index (BMI) is inversely associated with MD, with the breast being a fat storage site. We investigated the influence of abdominal fat distribution and adult weight gain on MD, taking age, BMI and other confounders into account. Because visceral adiposity and BMI are associated with breast cancer only after menopause, differences in pre- and post-menopausal women were also explored. We recruited 3,584 women aged 45-68 years within the Spanish breast cancer screening network. Demographic, reproductive, family and personal history data were collected by purpose-trained staff, who measured current weight, height, waist and hip circumferences under the same protocol and with the same tools. MD was assessed in the left craniocaudal view using Boyd's Semiquantitative Scale. Association between waist-to-hip ratio, adult weight gain (difference between current weight and self-reported weight at 18 years) and MD was quantified by ordinal logistic regression, with random center-specific intercepts. Models were adjusted for age, BMI, breast size, time since menopause, parity, family history of breast cancer and hormonal replacement therapy use. Natural splines were used to describe the shape of the relationship between these two variables and MD. Waist-to-hip ratio was inversely associated with MD, and the effect was more pronounced in pre-menopausal (OR = 0.53 per 0.1 units; 95 % CI = 0.42-0.66) than in post-menopausal women (OR = 0.73; 95 % CI = 0.65-0.82) (P of heterogeneity = 0.010). In contrast, adult weight gain displayed a positive association with MD, which was similar in both groups (OR = 1.17 per 6 kg; 95 % CI = 1.11-1.23). Women who had gained more than 24 kg displayed higher MD (OR = 2.05; 95 % CI = 1.53-2.73). MD was also evaluated using Wolfe's and Tabár's classifications, with similar results being obtained. Once BMI, fat distribution and other confounders were considered, our results showed a clear dose-response gradient between the number of kg gained during adulthood and the proportion of dense tissue in the breast.     

Height, body mass index, and prostate cancer: a follow-up of 950000 Norwegian men

The present study explored body mass index (BMI), height, and risk of prostate cancer in a large Norwegian cohort of 950000 men aged 20-74 years, whose height and weight were measured in a standardised way in the period 1963-1999. These were followed for an average of 21 years. The Cox proportional hazard models were used in the analyses. During follow-up, 33 300 histologically verified cases of prostate cancer were registered. The risk of prostate cancer increased by both BMI and height. The magnitude of the increase by BMI was modest, the relative risk (RR) of obese men (BMI>or=30) compared with normal weighted was 1.09 (95% CI: 1.04-1.15). However, the RR at age 50-59 years was 1.58 (95% CI: 1.29-1.94) in men being obese at about age 45 years compared with normal weighted men. The tallest men had an RR of 1.72 (95% CI: 1.46-2.04) compared with the shortest men. The overall effect of BMI on the incidence of prostate cancer was modest. The larger effect found in men aged 50-59 years might partly explain the previous inconsistent findings.