RESUMO
Background: Uric acid is the final product of purine metabolism and is a potent plasma antioxidant but with pro-inflammatory effects. At high levels, it may increase the risk of developing multiple chronic diseases, such as gout, atherosclerosis, hypertension, and renal diseases. The aim of this study was to assess the sex-specific association between serum bicarbonate and uric acid levels among healthy adults. Methodology: This retrospective cross-sectional study included 2,989 healthy Qatari adults (36.4 ± 11.1 years) from the Qatar Biobank database. Serum uric acid and bicarbonate levels were estimated alongside other serological markers. Participants free from chronic diseases were divided into four quartiles based on serum bicarbonate levels. The sex-specific relationship between serum bicarbonate and uric acid levels was assessed through univariate and multivariate analyses. Results: In men, low serum uric acid levels were significantly associated with higher quartiles of serum bicarbonate levels after adjusting for age. The association remained significant after further adjustment for BMI, smoking, and renal function. The subgroup analysis using the restricted cubic spline method confirmed a significant dose-response association between the variation coefficients of uric acid by serum bicarbonate level in men with adjustments for age, BMI, smoking, and renal function. In women, no significant association was found between quartiles of serum bicarbonate and uric acid levels following the same adjustments. However, using the restricted cubic spline method, a significant bidirectional relation was demonstrated between serum bicarbonate and the variation coefficients of uric acid that were positive for serum bicarbonate levels below 25 mEq/L and negative at higher levels. Conclusion: Serum bicarbonate levels are linearly associated with reduced serum uric acid levels among healthy adult men, which may be a potential protective factor against hyperuricemia-related complications. Further research is needed to determine the underlying mechanisms.
RESUMO
Background: Oxidative stress has been implicated as a fundamental mechanism in the decline of bone mass. Although serum uric acid (SUA) has potent antioxidant properties, the findings of many epidemiological and experimental studies couldn't draw a clear conclusion on the relation between SUA and bone health. We aim to investigate the association between SUA and bone mineral density (BMD) at different skeletal sites among healthy Qataris. Methodology: A cross-sectional analysis including total-body and site-specific bone mineral density scores and other serological markers of 2981 healthy Qatari adults (36.4 ± 11.1 years) from the Qatar biobank database was conducted. The study participants were divided into quartiles based on the level of SUA, and the BMD was measured using dual-energy X-ray absorptiometry (DXA). Multiple regression analyses were applied to investigate the association between SUA and BMD adjusting for multiple confounding factors. Results: High levels of SUA were significantly associated with the increased bone mineral density of the total body and at site-specific skeletal locations after adjusting for age and gender (p-value < 0.001). Further adjustment for body mass index (BMI), smoking, vitamin D, alkaline phosphatase, and estimated glomerular filtration rate (eGFR) levels attenuated the association but the association remained significant for individuals with high SUA levels (p-value ≤ 0.01).The association between SUA and BMD was not significant in non-obese, females, young adults, and smokers. However, no interaction was found between SUA and age, gender, BMI and smoking. Conclusion: Higher SUA levels are associated with a high bone density among healthy Qatari adults. However, such observation demands further investigations to outline the underlying mechanisms.
