Abstract 2777: DEXA measures of body fat percentage and relation to acute phase proteins among breast cancer survivors
Authors: Anne Dee, Roberta McKean-Cowdin, Marian L. Neuhouser, Cornelia M. Ulrich, Catherine M. Alfano, Richard M. Baumgartner, Anne McTiernan, Rachel Ballard-Barbash, Leslie Bernstein
Journal: Cancer Research (2010)

Abstract C-reactive protein (CRP) and serum amyloid A (SAA) are nonspecific acute phase proteins associated with chronic inflammation. Elevated CRP and SAA levels have been positively associated with obesity and the development and progression of a variety of diseases including breast cancer. The purpose of the current analysis was to examine the associations between body fat percentage as measured by dual energy x-ray absorptiometer (DEXA) and CRP and SAA and to determine whether lifestyle factors (weight change from diagnosis, physical activity level, caloric intake, or smoking status) modify these relationships in breast cancer survivors. The analysis utilized cross-sectional data obtained approximately 30 months after diagnosis for 138 Hispanic and Non-Hispanic-White breast cancer survivors participating in the Health, Eating, Activity, and Lifestyle (HEAL) Study. Regression models were used to calculate geometric means and 95% confidence intervals (CIs) for CRP and SAA by obesity status. Circulating levels of CRP and SAA were significantly associated with increased DEXA-measured adiposity. Obese breast cancer survivors (defined as women having body fat ≥35%) had significantly elevated levels of CRP (2.09 mg/L; 95%CI 1.70-2.56 vs. 0.78 mg/L; 95%CI 0.56-1.09) and SAA (6.51mg/L; 95%CI 5.70-7.44 vs. 3.75 mg/L; 95%CI 3.01-4.68) compared to non-obese survivors. Stratifying by tertile of % body fat revealed a statistically significant dose-response relationship. For CRP, geometric mean levels increased from 0.80 (95%CI 0.59, 1.08), to 1.74 (95%CI 1.32-2.29), to 2.71 (95%CI 2.03-3.64) with increasing tertile of % body fat (&amp;lt;36.2%, 36.2-42.8, &amp;gt;42.8). For SAA, geometric mean levels increased from 3.84 (95%CI 3.13, 4.71), to 5.98 (95%CI 4.98-7.18), to 7.32 (95%CI 6.03-8.90) by tertile of % body fat. Although not statistically significant, a trend emerged where obese women who reported recent use of non-steroidal anti-inflammatory drugs (NSAIDs) had lower geometric mean levels of CRP (1.66 vs. 2.38) and SAA (5.33 vs. 7.33) than obese women who did not take NSAIDs (p=.37 and p=.13 respectively). Additionally, women reporting high caloric intake (&amp;gt;2,000 kcal per day) had higher mean CRP levels than women reporting lower caloric intake, independent of % body fat (p=.01). Obesity remained a strong predictor of elevated levels of CRP/SAA in breast cancer survivors, regardless of stratification by other lifestyle factors. Our data suggest that adiposity is strongly associated with systemic inflammatory markers in breast cancer survivors. Our data provide some suggestive evidence that lifestyle choices, including NSAID use or caloric intake, may influence circulating levels of CRP and SAA. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2777.