Body mass index in relation to ovarian cancer: A multi‐centre nested case‐control study

Abstract

The incidence of ovarian cancer is up to 10 times higher in Western countries than in rural Asia and Africa. One common consequence of a Western lifestyle is the development of excessive body weight and obesity. A multi-centre prospective study was conducted to investigate the association between body mass index (BMI) and ovarian cancer risk. A case-control study was nested within 3 prospective cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). Information on anthropometry, demographic characteristics, medical history and lifestyle was obtained at the time of subjects' recruitment in each cohort. Women diagnosed with primary, invasive epithelial ovarian cancer from the 3 cohorts (n ‫؍‬ 122) diagnosed 12 months or later after recruitment into the respective cohort served as case subjects. For each case subject, 2 control subjects that matched the case subject on cohort, menopausal status, age and date of recruitment were randomly identified. Data were analyzed by conditional logistic regression. There was an inverse association between BMI and ovarian cancer risk. Key words: body mass index; height; anthropometry; ovarian cancer; prospective study; cohort Age-standardised incidence rates of ovarian cancer are up to 10 times higher in Western, industrialized countries than in rural Africa or Asia. 1 Migration studies have shown that women of Chinese and Japanese descent who reside in the U.S. tend to have higher incidence rates than their Asian counterparts and that in women 20 -49 years of age, the incidence of ovarian cancer is similar in U.S.-born Chinese women and U.S. white women. 2 These observations suggest that environmental factors related to a Western lifestyle may be associated with the increase in ovarian cancer risk. A common consequence of Western lifestyle, which has been shown to increase risk of some female cancers, such as postmenopausal breast and endometrial cancers, is the development of excessive body weight and obesity. Increase in body weight relative to body height, as reflected by an increased body mass index (BMI), may alter cancer risk through changes in endogenous hormone metabolism. [3][4][5] The role of a greater body weight is considerably clearer in relation to breast and endometrial cancers than to ovarian cancer, for which the majority of studies report non-significant associations. 5-8 A recent extensive review, including 29 reports on the association of body weight/BMI with ovarian cancer risk, concluded that there is a direct, however weak, association of increased BMI with ovarian cancer based on the results of cohort [summary OR 1.2 (1.1-1.3)] and populationbased case-control studies [summary OR 1.4 (1.2-1.6)]. 9 Hospitalbased case-control studies showed heterogeneous results; however, some of the differences in the results might reflect specific characteristics of the control groups included, e.g., a higher proportion of overweight women in the control series due to obesity-related conditions such as cardiovascular disease and diabetes. 9 In this paper, we report t...

Height, Body Mass Index, and Ovarian Cancer: A Pooled Analysis of 12 Cohort Studies

“…Odds ratios in the other five studies were all above unity, between 1.08 and 1.26 (10,12,(15)(16)(17). For the few studies that have investigated whether the association between height and ovarian cancer risk is modified by menopausal status, the association was stronger in or restricted to premenopausal women (21,56), which is in agreement with our analysis. Whether height is associated with histologic subtypes has been investigated in a few studies only.…”

“…The association was weaker and not statistically significant in prospective cohort studies in the systematic review (RR, 1.12; 95% CI, 0.95-1.32), and results between cohort studies were heterogeneous (28). Of the 17 (13, 19-21, 31-33, 37, 56-64) published cohort studies, 5 (13,19,31,33,37) were included in our pooled analysis and 2 were included in part (32,56). The 10 cohorts not included in this analysis have published mostly null associations, with the exception of Garfinkel (57) However, in our analysis, we observed that BMI was positively associated with ovarian cancer risk in women who were premenopausal.…”

Does IGF-1 play a role in the biology of ovarian cancer?

“…It would therefore be possible for taller women to be exposed to higher levels of serum IGF-1 during puberty and at a young age, which could result in an elevated risk for cancer transformation to OC. However, researchers the possible correlation between the increase in height and the risk for developing OC has been subject to much heated debate [18]. In our study, the height of OC and non-cancer patients did not differ significantly and thus, this parameter was not associated with OC and did not affect the obtained results.…”

Serum IGF-I, its major binding protein (IGFBP-3) and epithelial ovarian cancer risk: the European Prospective Investigation into Cancer and Nutrition (EPIC)

“…Association of ovarian cancer risk with tall stature will provide an indirect support for such theory as attained height strongly correlates with IGF-I during puberty, but not with hormone concentrations during adult life (Gunnell et al 2004). However, the association of height with ovarian cancer is not consistent (Lukanova et al 2002b, Engeland et al 2003. Another explanation for age modification would be that the effect of IGF-I on cancer risk may be dependent of high background estrogen concentrations as observed before menopause.…”