The impact of metabolic syndrome components on urinary parameters and risk of stone formation

• Published in: World journal of urology Vol. 39; no. 12; pp. 4483 - 4490
• Main Authors: Bamberger, Jacob N., Rosen, Daniel C., Khusid, Johnathan A., Kaplan-Marans, Elie, Gallante, Blair, Kapoor, Arjun, Paranjpe, Ishan, Atashsokhan, Danie J., Atallah, William M., Gupta, Mantu
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2021; Springer Nature B.V
• Subjects: Adult; Aged; Female; Humans; Hyperlipidemia; Insulin; Insulin resistance; Male; Medicine; Medicine & Public Health; Metabolic syndrome; Metabolic Syndrome - complications; Metabolic Syndrome - urine; Middle Aged; Multivariate analysis; Nephrolithiasis; Nephrolithiasis - etiology; Nephrology; Oncology; Original Article; Patients; pH effects; Retrospective Studies; Risk Assessment; Uric acid; Urinalysis; Urology; 24-Hour urinalysis; Nephrolithiasis; Metabolic syndrome; Diabetes mellitus
• ISSN: 0724-4983; 1433-8726
• DOI: 10.1007/s00345-021-03790-7

Purpose To investigate the relationship between metabolic syndrome (MS) and urinary abnormalities in stone-forming patients. Additionally, to delineate whether severity of urinary derangements is impacted by the number of co-occurring MS components. Methods Stone-forming patients who underwent initial metabolic workup prior to medical intervention at a comprehensive stone clinic were retrospectively reviewed and included in the study. Patients were given a six point (0–5) Metabolic Syndrome Severity Score (MSSS) based on the number of co-occurring MS components and split into six respective groups. Baseline clinical characteristics and metabolic profiles were compared between groups. Results Four-hundred-ninety-five patients were included in the study. Median age and median BMI was 58 years and 27.26 kg/m 2 , respectively. Several significant metabolic differences were noted, most notably a downward trend in median urinary pH ( p  < 0.001) and an upward trend in median urinary supersaturation uric acid ( p  < 0.001) across groups as MSSS increased. Multivariate analysis demonstrated an independent association between higher MSSS and increasing number of urinary abnormalities. A second multivariate analysis revealed that all MS components except hyperlipidemia were independently associated with low urinary pH. Additionally, obesity was independently associated with the greatest number of urinary abnormalities and had the strongest association with hyperuricosuria. Conclusions Prior research has attributed the strong association of nephrolithiasis and MS to high prevalence of UA nephrolithiasis and low urinary pH. Our findings indicate that all MS components with the exception of hyperlipidemia were independently associated with low urinary pH suggesting a mechanism independent from insulin resistance.