B-30 Exercise is Medicine/Poster - EIM: Cardiometabolic Problems Wednesday, May 28, 2014, 1:00 PM - 6:00 PMRoom: WB1
PURPOSE: The Women in Steady Exercise Research (WISER) Sister study was a three group parallel-arm RCT which tested the effect of two doses of aerobic exercise training (AEXT) on adipokines in women at risk for breast cancer. There is a purported link between AEXT and breast cancer risk, and one of the mechanisms proposed include alterations in adipokines.
METHODS: 128 healthy and sedentary women at risk for breast cancer (>18% lifetime risk according to Gail or Claus prediction models, documentation of a BRCA1 or BRCA2 mutation, or family member with deleterious mutation which conferred a 25% or higher probability of a deleterious mutation) were enrolled. The exercise intervention consisted of “low dose” (150 min/wk) and “high dose” (300 min/wk) exercise groups at an exercise intensity of 70-80% of age-predicted maximum heart rate. The control group was asked to continue their activities of daily living and not engage in new exercise programs. Body composition was measured by dual energy x-ray absorptiometry using a QDR 4500 Discovery (Hologic, Bedford, MA). Blood samples were drawn at baseline and follow up. Adiponectin and leptin were analyzed using commercially available ELISA kits (R&D Systems and Diagnostic Systems Labs, respectively).
RESULTS: The percent change in adiponectin level was significantly (P<.01) lower in the low dose group (-6.1 ± 18.6 %) compared to controls (7.3 ± 19.6 %). Leptin was not significantly altered between groups. However, we did observe that percent change in body fat was an independent predictor for the percent change of leptin. While there was a significant linear trend for decreases in percent body fat with AEXT dose (control: 0.6 ± 4.5 %, low: -2.9 ± 4.8 %, high: -3.7 ± 5.5 %), there were no interactions between body fat and treatment group in association with the percent change in leptin.
CONCLUSIONS: It was hypothesized AEXT in women would result in positive changes in adiponectin and leptin, and these changes would be dose dependent. While we did observe dose dependent decreases in body fat, the interaction between treatment group and body fat did not mediate alterations in adiponectin or leptin. Further, adiponectin levels dropped with low dose AEXT. It appears that in clinically healthy women at risk for breast cancer, AEXT, regardless of dose, does not beneficially alter adipokine levels.