Association Between the Uric Acid-to-Creatinine Ratio and Elevated Parathyroid Hormone Levels in Adults Without Known Parathyroid Disease

Background: Parathyroid hormone (PTH) is mainly regulated by calcium, vitamin D, and renal function, but metabolic factors may also influence its levels. The uric acid/creatinine (UA/Cr) ratio reflects uric acid metabolism and renal handling. This study evaluated its association with elevated PTH in adults without known parathyroid disease. Methods: This retrospective cross-sectional study included 244 adults undergoing routine biochemical evaluation. The uric acid-to-creatinine ratio (UA/Cr) was calculated. Participants were categorized according to PTH levels (≤65 pg/mL vs. >65 pg/mL). Logistic regression analyses were performed to identify factors associated with elevated PTH levels. Results: A total of 244 individuals (mean age 40.6 ± 11.7 years; 70.9% female) were included in the analysis. Participants with elevated PTH levels had significantly higher UA/Cr ratios compared with those with normal PTH levels (8.93 ± 1.82 vs. 7.47 ± 1.79, p = 0.031). In univariate logistic regression analysis, UA/Cr was associated with elevated PTH (OR 1.15, 95% CI 1.01–1.32, p = 0.043). In multivariable logistic regression analysis adjusting for vitamin D, magnesium, phosphorus, corrected calcium, age, sex, body mass index, and the estimated glomerular filtration rate, the UA/Cr ratio remained significantly associated with elevated PTH levels (OR 1.41, 95% CI 1.036–1.66, p = 0.024). Conclusions: The UA/Cr ratio was associated with elevated PTH levels in adults without known parathyroid disease, independently of vitamin D status, mineral metabolism parameters, and renal function. These findings suggest that the UA/Cr ratio may help characterize a broader metabolic context associated with elevated PTH levels, rather than serving as a diagnostic marker. Further prospective studies are needed to clarify the clinical relevance and direction of this association.