Relationship Between Changing Body Mass Index and Serum Uric Acid Alteration Among Clinically Apparently Healthy Korean Men

Objective: Gout and hyperuricemia incidence is increasing worldwide, reflecting pandemic overweight and obesity. However, the magnitude of the association of body mass index (BMI) changes with serum uric acid (UA) level in the general population has remained unevaluated. Methods: This retrospective cohort study enrolled 27,422 Korean men who underwent a comprehensive health check-up between 2015 and 2017. BMI change was categorized into 7 groups. The relationship between BMI change and serum UA level alteration was determined using multivariable regression models. Results: The mean age, BMI, and serum UA level were 38.8 years, 24.7 kg/m², and 6.2 mg/dl, respectively. All BMI change categories had a clear dose-response relationship with the serum UA level changes. The corresponding β coefficient of serum UA level changes was 0.13 (95% confidence interval [95% CI] 0.11, 0.16), 0.25 (95% CI 0.2, 0.3), and 0.44 (95% CI 0.36, 0.52) for a BMI decrease of 0.5–1.5, 1.5–2.5, and ≥2.5, respectively. Compared with no BMI change, the multivariate odds ratios of achieving normouricemia for a BMI increase of 0.5–1.5, 1.5–2.5, and ≥2.5 were 0.88 (95% CI 0.83, 0.95), 0.67 (95% CI 0.60, 0.75), and 0.60 (95% CI 0.49, 0.74), whereas those for a BMI decrease of 0.5–1.5, 1.5–2.5, and ≥2.5 were 1.17 (95% CI 1.07, 1.27), 1.28 (95% CI 1.08, 1.52), and 1.46 (95% CI 1.13, 1.88), respectively. Conclusion: BMI change could have a significant association with the alteration of serum UA levels of apparently healthy men. Despite its small effect size, the health risks and benefits of BMI change would be emphasized for serum UA level alteration.