Weight Reduction and Target Serum Urate Level: A Longitudinal Study of Annual Medical Examination.

Abstract

To evaluate associations of weight reduction with serum urate (SU) changes and achieving an SU <6 mg/dl in the real-world setting, outside of specific weight reduction interventions. We analyzed systematically collected data of annual medical examination participants from October 2012 to October 2022. Exposure was weight change (increase or decrease) between two consecutive visits, categorized as minimal (≤0.9 kg, reference), small (1.0-4.9 kg), moderate (5.0-9.9 kg), and large (≥10 kg). Outcomes included SU changes between two consecutive visits and achieving SU <6 mg/dL in hyperuricemic participants (SU ≥7 mg/dL at the prior visit). We identified 58,630 eligible participants (median age 46 years, female 51.3%, overweight 19.4%, median SU 5.3 mg/dL, history of gout and/or hyperuricemia 5.6%) with 336,814 visits over a median of 5.3 years. After adjusting for relevant covariates, linear general estimating equations estimated mean SU changes (95%CI) based on observed weight reductions (vs. minimal changes): small -0.10 (-0.10, -0.09) mg/dL, moderate -0.34 (-0.36, -0.32) mg/dL, and large -0.64 (-0.70, -0.58) mg/dL. In hyperuricemic participants, adjusted relative risks (95%CI) for achieving SU level <6 mg/dL by modified Poisson regression were 1.25 (1.15, 1.37) in small, 2.82 (2.43, 3.27) in moderate, and 5.27 (4.15, 6.70) in large weight reductions, with corresponding NNT of 61.1 for small weight reductions, 8.5 for moderate, and 3.6 for large. Small weight reductions were associated with only small SU changes. Some hyperuricemic participants can achieve the target SU level with moderate to large weight reductions.