Body Size and Breast Cancer Risk in Black Women and White Women: The Carolina Breast Cancer Study

Abstract

The relation between body size and breast cancer risk was investigated in a population-based, case-control study of Black women (350 cases, 353 controls) and White women (523 cases, 471 controls) from North Carolina, aged 20-74 years in 1993-1996. Logistic regression analyses compared tertiles of each body size variable, adjusting for age and breast cancer risk factors (results shown for highest relative to lowest tertile). Among premenopausal women, body mass index (kg/m2) was inversely associated with breast cancer (odds ratio (OR) = 0.46, 95% confidence interval (CI): 0.26, 0.80) for Whites but not for Blacks. There was essentially no association among postmenopausal women. Higher waist/hip ratio, adjusted for body mass index, increased risk for all women. Odds ratios for Black and White premenopausal women were 2.50 (95% CI: 1.10, 5.67) and 2.44 (95% CI: 1.17, 5.09), respectively; odds ratios for Black and White postmenopausal women were 1.62 (95% CI: 0.70, 3.79) and 1.64 (95% CI: 0.88, 3.07), respectively. Findings for body mass index differed among Black women when stratified by age (<50 years) (OR = 0.50, 95% CI: 0.25, 1.01) instead of menopausal status. Thus, the associations of breast cancer with body mass index and waist/hip ratio among Black women are similar to those documented for Whites, despite different body size profiles on average.

A Prospective Study of Body Size and Breast Cancer in Black Women

“…A population-based case-control study that included 350 Black breast cancer cases (Carolina Breast Cancer Study) did not observe an increased risk of postmenopausal breast cancer in women who were overweight or obese; nor did a cohort study of breast cancer mortality (Cancer Prevention Study II; ref. 13). Hospital-based case-control studies yielded conflicting results (10)(11)(12) + .…”

“…Several case-control studies have reported on the relation of obesity to breast cancer risk in African American women separately by menopausal status, with inconsistent results (10)(11)(12)(13)(14). There was little evidence of an association of current body mass index (BMI) with risk of breast cancer in premenopausal women (10)(11)(12)(13)(14).…”

“…There was little evidence of an association of current body mass index (BMI) with risk of breast cancer in premenopausal women (10)(11)(12)(13)(14). Among postmenopausal women, high BMI was associated with an increased risk (11,14), a reduced risk (12,13), or there was no association (10). In addition, the Cancer Prevention Study II (15) provided data on BMI and death from breast cancer during 20 years of followup, with a total of 257 breast cancer deaths among Black women; there was not a statistically significant association of BMI with risk of breast cancer mortality.…”

Risk Factors for Premenopausal Breast Cancer: A Case-control Study in Uruguay

“…Concerning anthropometry, it is accepted that higher values of body mass index (BMI) are associated with a reduced risk of BC in premenopausal women and with an increased risk in postmenopausal ones (Lahmann et al, 2004;WCRF, 2007). Absence of association in premenopausal women has been also described for certain anthropometric measures in some populations such as Chinese (Shu et al, 2001;Chow et al, 2005), Japanese (Hirose et al, 2001), or African American women (Hall et al, 2000), different from what has been consistently described in the Western and Caucasian societies. Recently, waist-to-hip ratio was also associated with an increase of risk in premenopausal Nigerian (Okobia et al, 2006) and Asian American women (Wu et al, 2007).…”

Somatotype and risk of breast cancer: a case-control study in Uruguay

“…Some studies examined regional adiposity and BC risk [4][5][6][7][8][9][10][11] . A positive association of central adiposity with postmenopausal BC risk and also a weaker association for premenopausal women were found in most of these studies.…”