Lower Socioeconomic Status is Associated With Adverse Urinary Markers and Surgical Complexity in Kidney Stone Patients

Abstract

Objective: To determine if socioeconomic status (SES) correlates with severity of kidney stone disease and 24-hour urine parameters.

Materials and methods: An IRB approved prospectively maintained database for nephrolithiasis was retrospectively analyzed for both 24-hour urine results and surgical procedures performed from 2009 to 2019. Severely distressed communities (SDC) were categorized as those with a Distressed Communities Index (DCI), a composite measure of SES, score in the top quartile (lowest for SES). Univariate and multivariate analyses were performed to evaluate the strength of the association of DCI on: stone size at presentation, need for and type of surgical procedure, need for staged surgery and specific stone risk factors in 24-hour urine collections.

Results: Surgical procedures were performed on 3939 patients (1978 women) who were not from SDC and 200 (97 women) from SDC. Patients from SDC were older (57.1 years vs 54.2 years; P = .009). Patients from SDC were more likely to undergo proportionally more invasive procedures (17.5% vs 11.6%; P = .011) and require staged surgery at a higher rate (13.0% vs 8.5%; P = .028). Men from SDC had larger stones (12.5 mm vs 9.7 mm; P = .001). Among 24-hour urine results from 2454 patients (1187 women), DCI was not correlated with sodium, calcium, magnesium, volume, oxalate, phosphate, and pH levels. Higher DCI (lower SES) correlated with lower urine citrate (P = .001) and lower urine potassium (P = .002).

Conclusion: SES correlates with larger stone burden at the time of urologic intervention, requires proportionally more invasive procedures and more staged procedures. Lower SES correlated with lower urine citrate and potassium.