DEXA measures of body fat percentage and acute phase proteins among breast cancer survivors: a cross-sectional analysis

Abstract

Background: C-reactive protein (CRP) and Serum amyloid A protein (SAA) increases with systemic inflammation and are related to worse survival for breast cancer survivors. This study examines the association between percent body fat and SAA and CRP and the potential interaction with NSAID use and weight change.

Methods: Participants included 134 non-Hispanic white and Hispanic breast cancer survivors from the Health, Eating, Activity, and Lifestyle Study. Body fat percentage, measured with Dual Energy X-ray Absorptiometer (DEXA), and circulating levels of CRP and SAA were obtained 30 months after breast cancer diagnosis.

Results: Circulating concentrations of CRP and SAA were associated with increased adiposity as measured by DEXA after adjustment for age at 24-months, race/ethnicity, dietary energy intake, weight change, and NSAID use. Survivors with higher body fat ≥35% had significantly higher concentrations of CRP (2.01 mg/l vs. 0.85 mg/l) and SAA (6.21 mg/l vs. 4.21 mg/l) compared to non-obese (body fat < 35%). Women who had gained more than 5% of their body weight since breast cancer diagnosis had non-statistically significant higher geometric mean levels of CRP and SAA. Mean levels of CRP and SAA were higher among obese women who were non-users of NSAIDs compared to current users; the association with SAA reached statistical significance (Mean SAA = 7.24, 95%CI 6.13-8.56 for non-NSAID; vs. 4.87; 95%CI 3.95-6.0 for NSAID users respectively).

Conclusions: Breast cancer survivors with higher body fat had higher mean concentrations of CRP and SAA than women with lower body fat. Further assessment of NSAID use and weight control in reducing circulating inflammatory markers among survivors may be worthwhile to investigate in randomized intervention trials as higher inflammatory markers are associated with worse survival.

Figure 1

Definition of study population and exclusion criteria. Flow chart of the population analyzed within the HEAL cohort.

Figure 2

Scatterplot and predicted regression line of log_e(CRP) centered on body fat percentage. Scatterplot and predicted regression line of log_e(CRP) centered on body fat percentage on a sample of 134 breast cancer survivors from the HEAL study controlling for age, caloric intake (kcal), weight difference(kg), and NSAID use.

Figure 3

Scatterplot and predicted regression lines of log_e(SAA) centered on body fat percentage. Scatterplot and predicted regression lines of log_e(SAA) centered on body fat percentage on a sample of 134 breast cancer survivors from the HEAL study controlling for age, history of arthritis, caloric intake (kcal), weight difference(kg), and NSAID use.