Association between serum uric acid level and bone mineral density in Chinese gout patients: a cross-sectional study

Background Previous studies have suggested that elevated levels of serum uric acid (sUA) exert significant protective effects against osteoporosis in healthy individuals. However, the effects of sUA levels on bone mineral density (BMD) and bone turnover markers (BTMs) in gout patients, as well as the risk factors for osteopenia in this population, remain unclear. Our study aimed to analyse the risk factors for osteopenia in gout patients and investigate the effects of sUA levels on bone metabolism. Methods Patients were categorized into two groups based on their BMD, including the low BMD group (comprising both osteopenia and osteoporosis patients, given the small number of individuals in the osteoporosis subgroup) and the normal BMD group. We compared their clinical characteristics, incorporated sUA into a logistic regression analysis and applied restricted cubic splines (RCSs) to evaluate potential nonlinear dose-response relationships. Multivariate linear regression models were subsequently used to investigate the associations between sUA levels and BMD. Furthermore, subgroup analyses were performed. Results Compared with patients in the normal BMD group, patients in the low BMD group were older and had significantly greater sUA levels but lower BMI values ( P < 0.05). Logistic regression analysis revealed that high sUA levels were an independent risk factor for osteopenia. RCS analyses revealed a linear relationship between sUA levels and the risk of osteopenia. Multivariate linear regression analyses adjusted for sex, age, body mass index (BMI), and other potential confounders demonstrated a significant negative correlation between sUA levels and BMD at all skeletal sites. Furthermore, subgroup analyses revealed an inverse association between sUA levels and lumbar spine BMD in participants with a BMI <28 kg/m 2 and those aged ≥ 50 years. Conclusion Among hospitalized patients with stable-stage gout, sUA levels were negatively associated with BMD in gout patients . Higher sUA levels (particularly > 9.4 mg/dL) were linked to a greater likelihood of low BMD, especially in older and nonobese individuals.