Abstract P225: Effect of Weight Loss Strategies on Serum Uric Acid in Cancer Patients in the Spirit Study

Abstract

Introduction: Obesity is strongly associated with elevated serum uric acid (SUA), a hypothesized mediator of cardiovascular disease. In observational studies, weight loss is associated with lower SUA. However, trial evidence on weight loss and SUA is lacking. Hypothesis: We hypothesized that in a randomized, controlled setting, intentional weight loss would reduce SUA. Methods: The Survivorship Promotion In Reducing IGF-1 Trial (SPIRIT) was a three-arm, parallel trial of overweight or obese adult cancer survivors that compared the effects of a coach-directed weight loss intervention or metformin to self-directed weight loss (ref) on insulin growth factor-1 (IGF-1) over a 1-year period. Participants in the coach-directed arm underwent behavioral-based telephonic coaching with web-based support to promote healthy lifestyle and weight loss, targeting a 5% weight loss in the first 6 months. Participants assigned metformin received up to 2,000 mg daily. In our study, SUA was measured in specimens collected at baseline, 3-months, 6-months, and 12-months. Results: There were 121 participants, with a mean age of 60 years (standard deviation [SD]: 9), and a mean body mass index (BMI) of 35 kg/m 2 (SD: 5). Compared to the self-directed group, coach-directed weight loss reduced BMI by 0.6 kg/m 2 (95% CI: 0.1, 1.1) and metformin reduced BMI by 0.9 kg/m 2 (95% CI: 0.4, 1.5) over 12 months. However, compared to the self-directed group, coach-directed weight loss significantly increased SUA by 0.3 mg/dL (95% CI: 0.1, 0.6) over 12 months, while metformin did not significantly affect SUA (0.2 mg/dL; 95% CI: -0.04, 0.5). The increase observed with the coach-directed weight loss intervention occurred primarily within the first 3 months of the intervention (Figure). Conclusions: Contrary to our expectations, intentional weight loss increased SUA in the short-term. These results question weight loss as a strategy for SUA reduction. Studies testing the long-term effects of weight loss on SUA are needed.