Variation in the Intensity of Care for Patients with Uncomplicated Renal Colic Presenting to U.S. Emergency Departments

Abstract

Background: Renal colic results in > 1 million ED visits per year, yet there exists a gap in understanding how the majority of these visits, namely uncomplicated cases, are managed.

Objective: We assessed patient- and hospital-level variation for emergency department (ED) management of uncomplicated kidney stones.

Methods: We identified ED visits from non-elderly adults (aged 19-79 years) with a primary diagnosis indicating renal stone or colic from the 2011 Nationwide Emergency Department Sample. Patients with additional diagnostic codes indicating infection, sepsis, and abdominal aortic aneurysm were excluded. We used sample-weighted logistic regression to determine the association between hospital admission and having a urologic procedure with patient and hospital characteristics.

Results: Of the 1,061,462 ED visits for uncomplicated kidney stones in 2011, 8.0% of visits resulted in admission and 6.3% resulted in an inpatient urologic procedure. Uninsured patients compared to Medicaid insured patients were less likely to be admitted or have an inpatient urologic procedure (odds ratio [OR] = 0.72; 95% confidence interval [CI] 0.65-0.81 and OR = 0.80; 95% CI 0.72-0.87, respectively). Private- and Medicare-insured patients compared to Medicaid-insured patients were more likely to have an inpatient urologic procedure (OR = 1.20; 95% CI 1.11-1.30 and OR = 1.14; 95% CI 1.04-1.25, respectively).

Conclusions: For patients with uncomplicated renal colic, there is variation in the management associated with nonclinical factors, namely insurance. No consensus guidelines exist yet to address when to admit or utilize inpatient urologic procedures.

Keywords: HCUP; Healthcare Cost and Utilization Project; Medicaid; emergency departments; insurance; kidney stones; nephrolithiasis; renal colic; variation.