Category: Epidemiology, Health Policy, Socioeconomics & Outcomes

MP33-3 - Travel Patterns for Patients Undergoing Stone Surgery in the State of California, 2005-2016

Sun, Sep 23
2:00 PM - 4:00 PM

Introduction & Objective :

According to the 2017 American Urological Association census, 62.2% of counties in the United States are without any practicing urologists and 89.3% of urologists practice in metropolitan areas. We aimed to determine the pattern and factors associated with kidney stone patients traveling within the state of California (CA) to undergo ureteroscopy (URS), shockwave lithotripsy (SWL), and percutaneous nephrolithotomy (PCNL).

Methods :

We investigated CA's Office of Statewide Health Planning and Development (OSHPD) public inpatient and ambulatory surgical databases from 2005-2016 for URS, SWL, and PCNL. Aggregated data was then split into three cohorts based on patient and hospital county: patients a) not traveling, b) traveling within and c) traveling outside a CA labor market region. Multivariate logistic regression was performed using variables of age, race, gender, payer group, number of surgeries, urologists, and comorbid conditions. ArcMap 10.5 created choropleth and radial flow maps<./p>

Results :

356,829 surgeries were performed for stones in CA from 2005-2016. Patients left their county for 61,679 (17.3%) surgeries, traveling an average of 70 miles (112 km).  SWL was negatively associated with travel independent of age, race, gender, and payer group (p < 0.01 for all), while no association for URS and PCNL with travel was observed. Independent of procedure type, and controlling for the number of urologists, private insurance or Medicare was associated with travel within (p < 0.001; OR 11.4) and out of a region (p=0.008; OR = 2.67). Non-white race was negatively associated with travel within (p <0.001; OR 0.07) or out of (p=0.034; OR = 0.45) a region. Overall, patients tended to travel from areas with few urologists to areas with many urologists and rarely travel great distance (Figure).

Conclusions :

Stone patients are significantly more likely to receive SWL locally than PCNL or URS. Non-white patients or those on Medicaid are significantly more likely to receive care locally, if available, when compared to white patients or those with private insurance or Medicare. The predictable pattern of travel observed in our study is relevant to identify patient populations who may not have adequate access to care, the establishment of hospital network satellite facilities, and targeted marketing.

Scott Wiener

Clinical Fellow
San Francisco, California

Scott Wiener is a clincal fellow in endourology at UCSF.

David Bayne

Clinical Fellow
San Francisco, California

David Bayne, MD, MPH
UCSF Urology Endo/Lap Fellow
Pager: 415-443-4394
Cellphone: 617-571-5870

BA in Biochemistry at Harvard College 2006
MD at Harvard Medical School 2012
MPH at UC Berkeley in 2017
Residency in Urology at UCSF 2018

David T. Tzou

Assistant Professor
University of Arizona
Tucson, Arizona

Thomas Chi

Associate Professor
San Fransisco, California

Thomas Chi, MD
Associate Professor
Associate Chair for Clinical Affairs
Kutzmann Endowed Professor for Clinical Urology
UCSF Department of Urology

Dr. Thomas Chi, MD, graduated as a President's Scholar from Stanford University with a BA in Human Biology and MAs in Sociology and Music. He earned his MD from the University of California, San Francisco where he also completed urology residency and a fellowship in Endourology and Laparoscopy under the mentorship of Dr. Marshall L. Stoller.

During his fellowship, Dr. Chi was awarded grant funding from the National Institutes of Health and the American Urological Association Urology Care Foundation to research the fundamental mechanisms underlying the formation of urinary stones.

Clinical Interests

He joined the UCSF faculty of the Department of Urology in 2013 where his clinical interests include the care of patients with urinary stone disease and those in need of minimally invasive surgery. He specializes in the performance of endoscopic, laparoscopic, and percutaneous surgeries as well as HoLEP. He has established ReSKU, the Registry for Stones of the Kidneys and Ureter, the first kidney stone registry of its kind for tracking patient clinical outcomes and is an internationally recognized specialist in the use of ultrasound in the management of kidney stones to minimize patient radiation exposure.

Research Interests

In addition to his clinical interests, Dr. Chi supervises an NIH-funded translational science lab where he leads a cross-disciplinary research team. His research focuses on understanding the genetic and microbial environment of the kidney related to how kidney stones form and developing new medical preventative interventions. He has developed a novel model fruit fly for the study of kidney stones and has published over 80 peer-reviewed articles and book chapters spanning both basic science as well as epidemiologic approaches centered around improving the care of patients with urinary stone disease.

Marshall L. Stoller

San Francisco, California