Obesity has been associated with an increased risk of postmenopausal
breast cancer.
Adipokines and systemic
inflammation have been hypothesized to underlie this association. In a case-control study nested within the Multiethnic Cohort, conditional logistic regression was used to calculate the
ORs and 95% confidence intervals (CI) for postmenopausal
breast cancer associated with prediagnostic levels of serum
leptin,
adiponectin, the
leptin:
adiponectin ratio, and
C-reactive protein (CRP). The 706 cases and 706 controls were matched on ethnicity, location (Hawaii or Los Angeles), birth year, date and time of blood draw, hours fasting before blood draw, and
hormone replacement therapy use at blood draw. Higher circulating levels of
leptin [ORQ4 vs. Q1, 1.94 (1.37-2.75); Ptrend ≤ 0.001), the
leptin:
adiponectin ratio [OR, 1.91 (1.36-2.68); Ptrend = 0.005], and CRP [OR, 1.41 (1.01-1.96); Ptrend = 0.014] were associated with an increased risk of postmenopausal
breast cancer. The positive associations for these markers remained after adjustment for body mass index (BMI). No associations were detected for
adiponectin. These data suggest that
adipokines and systemic
inflammation may be associated with the risk of postmenopausal
breast cancer independently of BMI. Further prospective studies examining the role of
adipokines and inflammatory processes in the etiology of postmenopausal
breast cancer are warranted.
Cancer Prev Res; 6(3); 188-95. ©2013 AACR.