Endocrine Care 485
Sex Hormone Binding Globulin and Risk of Breast Cancer in Postmenopausal Women: A Meta-Analysis of Prospective Studies
Authors
X. Y. He1, Y. D. Liao2, S. Yu3, Y. Zhang4, R. Wang3
Affiliations
1
Key words ▶ breast cancer ● ▶ sex hormone binding ● globulin ▶ meta-analysis ●
Abstract
Bibliography DOI http://dx.doi.org/ 10.1055/s-0034-1395606 Published online: January 7, 2015 Horm Metab Res 2015; 47: 485–490 © Georg Thieme Verlag KG Stuttgart · New York ISSN 0018-5043 Correspondence X. Y. He Department of Oncology People’s Hospital of Ganzhou Ganzhou 341000 China Tel.: + 86/797/5559947 Fax: + 86/797/5559947 [email protected] R. Wang Department of Endocrinology Affiliated Hospital of Qingdao University Qingdao 262203 China Tel.: + 86/532/82911740 Fax: + 86/532/82911740 [email protected]
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Previous studies on the association between sex hormone binding globulin (SHBG) level and risk of breast cancer in postmenopausal women reported conflicting results. A meta-analysis of prospective studies was performed to evaluate the association between SHBG level and risk of breast cancer in postmenopausal women. Pubmed (1980 to July 2014) and EMBASE (1988 to July 2014) were searched for eligible studies. Eligible studies were prospective cohort or nested case-control studies on the association between SHBG level and risk of breast cancer in postmenopausal women. Meta-analysis using random-effects model was performed to calculate the pooled risk ratios (RRs) with 95 %
Introduction
▼
Breast cancer is the most common cancer in women, and it has caused serious damage to human health [1, 2]. Breast cancer caused 458 503 deaths worldwide in 2008, and it accounted for 13.7 % of cancer deaths in women [1]. Previous studies have suggested that the development of breast cancer may result from a combination of several factors, such as obesity, smoking, sex hormones, and genetic mutations [3–7]. Thus, breast cancer risk is partially determined by severalrelated factors, and it has been well accepted that high levels of endogenous sex hormones may increase the risk of developing breast cancer, such as estrogens [6]. Previous studies have shown that endogenous sex hormones are intensively associated with risk of breast cancer, especially in premenopausal women [6]. Sex hormone-binding globulin (SHBG) may have biologic functions beyond simply regulation of the levels of free sex hormones [8, 9]. Classically, the primary function of sex hormone-binding globu-
c onfidence intervals (95 % CIs). Of 946 studies identified, 26 prospective studies from 21 publications were finally included in the meta-analysis. In postmenopausal women, the pooled RR for breast cancer comparing highest with lowest categories of SHBG was 0.64 (95 % CI 0.57–0.72, p
Sex Hormone Binding Globulin and Risk of Breast Cancer in Postmenopausal Women: A Meta-Analysis of Prospective Studies
Authors
X. Y. He1, Y. D. Liao2, S. Yu3, Y. Zhang4, R. Wang3
Affiliations
1
Key words ▶ breast cancer ● ▶ sex hormone binding ● globulin ▶ meta-analysis ●
Abstract
Bibliography DOI http://dx.doi.org/ 10.1055/s-0034-1395606 Published online: January 7, 2015 Horm Metab Res 2015; 47: 485–490 © Georg Thieme Verlag KG Stuttgart · New York ISSN 0018-5043 Correspondence X. Y. He Department of Oncology People’s Hospital of Ganzhou Ganzhou 341000 China Tel.: + 86/797/5559947 Fax: + 86/797/5559947 [email protected] R. Wang Department of Endocrinology Affiliated Hospital of Qingdao University Qingdao 262203 China Tel.: + 86/532/82911740 Fax: + 86/532/82911740 [email protected]
▼
Previous studies on the association between sex hormone binding globulin (SHBG) level and risk of breast cancer in postmenopausal women reported conflicting results. A meta-analysis of prospective studies was performed to evaluate the association between SHBG level and risk of breast cancer in postmenopausal women. Pubmed (1980 to July 2014) and EMBASE (1988 to July 2014) were searched for eligible studies. Eligible studies were prospective cohort or nested case-control studies on the association between SHBG level and risk of breast cancer in postmenopausal women. Meta-analysis using random-effects model was performed to calculate the pooled risk ratios (RRs) with 95 %
Introduction
▼
Breast cancer is the most common cancer in women, and it has caused serious damage to human health [1, 2]. Breast cancer caused 458 503 deaths worldwide in 2008, and it accounted for 13.7 % of cancer deaths in women [1]. Previous studies have suggested that the development of breast cancer may result from a combination of several factors, such as obesity, smoking, sex hormones, and genetic mutations [3–7]. Thus, breast cancer risk is partially determined by severalrelated factors, and it has been well accepted that high levels of endogenous sex hormones may increase the risk of developing breast cancer, such as estrogens [6]. Previous studies have shown that endogenous sex hormones are intensively associated with risk of breast cancer, especially in premenopausal women [6]. Sex hormone-binding globulin (SHBG) may have biologic functions beyond simply regulation of the levels of free sex hormones [8, 9]. Classically, the primary function of sex hormone-binding globu-
c onfidence intervals (95 % CIs). Of 946 studies identified, 26 prospective studies from 21 publications were finally included in the meta-analysis. In postmenopausal women, the pooled RR for breast cancer comparing highest with lowest categories of SHBG was 0.64 (95 % CI 0.57–0.72, p
