Diabetes, Obesity, and Pathological Upstaging in Renal Cell Carcinoma: Results From a Large Multi-institutional Consortium.

PURPOSE: We sought to determine whether clinical risk factors and morphometric features on preoperative imaging can be utilized to identify those patients with cT1 tumors who are at higher risk of upstaging (pT3a). MATERIALS AND METHODS: We performed a retrospective international case-control study of consecutive patients treated surgically with radical or partial nephrectomy for nonmetastatic renal cell carcinoma (cT1 N0) conducted between January 2010 and December 2018. Multivariable logistic regression models were used to study associations of preoperative risk factors on pT3a pathological upstaging among all patients, as well as subsets with those with preoperative tumors ≤4 cm, renal nephrometry scores, tumors ≤4 cm with nephrometry scores, and clear cell histology. We also examined association with pT3a subsets (renal vein, sinus fat, perinephric fat). RESULTS: Among the 4,092 partial nephrectomy and 2,056 radical nephrectomy patients, pathological upstaging occurred in 4.9% and 23.3%, respectively. Among each group independent factors associated with pT3a upstaging were increasing preoperative tumor size, increasing age, and the presence of diabetes. Specifically, among partial nephrectomy subjects diabetes (OR=1.65; 95% CI 1.17, 2.29), male sex (OR=1.62; 95% CI 1.14, 2.33), and increasing BMI (OR=1.03; 95% CI 1.00, 1.05 per 1 unit BMI) were statistically associated with upstaging. Subset analyses identified hilar tumors as more likely to be upstaged (partial nephrectomy OR=1.91; 95% CI 1.12, 3.16; radical nephrectomy OR=2.16; 95% CI 1.44, 3.25). CONCLUSIONS: Diabetes and higher BMI were associated with pathological upstaging, as were preoperative tumor size, increased age, and male sex. Similarly, hilar tumors were frequently upstaged.

Diagnosis, Management, and Follow-Up of the Incidentally Discovered Adrenal Mass: CUA Guideline Endorsed by the AUA.

PURPOSE: Incidental adrenal masses are common and require a multidisciplinary approach to evaluation and management that includes family physicians, urologists, endocrinologists, and radiologists. The purpose of this guideline is to provide an updated approach to the diagnosis, management, and follow-up of adrenal incidentalomas, with a special focus on the areas of discrepancy/controversy existing among the published guidelines from other associations. MATERIALS AND METHODS: This guideline was developed by the Canadian Urological Association (CUA) through a working group comprised of urologists, endocrinologists, and radiologists and subsequently endorsed by the American Urological Association (AUA). A systematic review utilizing the GRADE approach served as the basis for evidence-based recommendations with consensus statements provided in the absence of evidence. For each guideline statement, the strength of recommendation was reported as weak or strong, and the quality of evidence was evaluated as low, medium, or high. RESULTS: The CUA working group provided evidence- and consensus-based recommendations based on an updated systematic review and subject matter expertise. Important updates on evidence-based radiological evaluation and hormonal testing are included in the recommendations. This guideline clarifies which patients may benefit from surgery and highlights where short term surveillance is appropriate. CONCLUSION: Incidentally detected adrenal masses require a comprehensive assessment of hormonal function and oncologic risk. This guideline provides a contemporary approach to the appropriate clinical, radiographic, and endocrine assessments required for the evaluation, management, and follow-up of patients with such lesions.

Volumetric Analysis of Renal Masses as Predictors of Partial Nephrectomy Outcomes.

Objective: To examine the role of endophytic tumor volume (TV) assessment (endophycity) on perioperative partial nephrectomy (PN) outcomes. Patients and Methods: Retrospective review of 212 consecutive laparoscopic and open partial nephrectomies from single institution using preoperative imaging and 1-year follow-up. Demographics, comorbidities, RENAL nephrometry scores, and all peri- and postoperative outcomes were recorded. Volumetric analysis performed using imaging software, independently assessed by two blinded radiologists. Univariate and multivariate statistical analysis were completed to assess predictive value of endophycity for all clinically meaningful outcomes. Results: Among those undergoing minimally invasive surgery (MIS), lower tumor endophycity was associated with higher likelihood of trifecta outcome (negative surgical margin, <10% decline in estimated glomerular filtration rate, the absence of complications) irrespective of max tumor size. For MIS, estimated blood loss increased with greater tumor endophycity regardless of tumor size. Among those who underwent open partial nephrectomy, lower tumor endophycity was associated with trifecta outcomes for tumors >4 cm only. On multivariate analysis with log-scaled odds ratios (OR), tumor endophycity and total kidney volume had the strongest correlation with tumor-related complications (OR = 3.23, 2.66). The analysis identified that tumor endophycity and TV on imaging were inversely correlated with of trifecta outcomes (OR = 0.53 for both covariates). Conclusions: Volumetric assessment of tumor endophycity performed well in identifying PN outcomes. As automated imaging software improves, volumetric analysis may prove to be a useful adjunct in preoperative planning and patient counseling.

Renal colic imaging practice patterns in Ontario A population-based study.

INTRODUCTION: Computed tomography (CT) is associated with increased cost and exposure to radiation when compared to ultrasound (US) in patients with renal colic. Consequently, a 2014 Choosing Wisely recommendation states US should be used over CT in uncomplicated presentations in patients under age 50. The objective of this study was to describe imaging practice patterns in Ontario among patients presenting with renal colic and the relationship between initial imaging modality, subsequent imaging, and burden of care indicators. METHODS: This is a population-based study of patients who presented with renal colic in Ontario from 2003-2019 using administrative data. Patients were assessed according to their first imaging modality during their index visit. Descriptive statistics and Chi-squared test were used to examine differences between these groups. The primary outcome was the need for subsequent imaging. Secondary outcomes were length of renal colic episode, days to surgery, and number of emergency department (ED ) and primary care visits during the renal colic episode. Univariate and multivariable logistic regression models were used. RESULTS: A total of 429 060 patients were included in the final analysis. Of those, 50.5% (216 747) had CT as their initial imaging modality, 20% (84 672) had US, and 3% (13 643) had both on the same day. Subsequent imaging was obtained in 40.7% of those who had CT as the initial imaging, compared to 43% in those who had US and 43% who had both. Of those who initially had an US, 38% went on to have at least one CT during their renal colic episode, including those who had CT on the same day as initial US, while 62% were able to avoid CT altogether. In contrast, 17% had a repeat CT after an initial CT at the time of presentation. The overall use of US increased from 15% to 31% during the study period. The length of the renal colic episode was slightly longer in those who had a CT first compared to US in multivariable models (adjusted risk ratio [ARR ] 1.005, 95% confidence interval [CI] 1.000-1.009); however, the time to surgery was less in those who had a CT first (ARR 0.831, 95% CI 0.807-0.856). Fewer ED and family physician visits were seen in those who had an initial CT. CONCLUSIONS: In patients with renal colic in Ontario, approximately half have CT as the initial imaging modality despite US being recommended in uncomplicated presentations. While US use remains low, its use doubled during this study period, demonstrating an encouraging trend. Those who have US first can often avoid subsequent CT.

A multivariate genetic analysis of anxiety sensitivity, environmental sensitivity and reported life events in adolescents.

BACKGROUND: Despite being considered a measure of environmental risk, reported life events are partly heritable. One mechanism that may contribute to this heritability is genetic influences on sensitivity, relating to how individuals process and interpret internal and external signals. The aim of this study was to explore the genetic and environmental overlap between self-reported life events and measures of sensitivity. METHODS: At age 17, 2,939 individuals from the Twins Early Development Study (TEDS) completed measures of anxiety sensitivity (Children's Anxiety Sensitivity Index), environmental sensitivity (Highly Sensitive Child Scale) and reported their experience of 20 recent life events. Using multivariate Cholesky decomposition models, we investigated the shared genetic and environmental influences on the associations between these measures of sensitivity and the number of reported life events, as well as both negative and positive ratings of life events. RESULTS: The majority of the associations between anxiety sensitivity, environmental sensitivity and reported life events were explained by shared genetic influences (60%-75%), with the remainder explained by nonshared environmental influences (25%-40%). Environmental sensitivity showed comparable genetic correlations with both negative and positive ratings of life events (rA  = .21 and .15), anxiety sensitivity only showed a significant genetic correlation with negative ratings of life events (rA  = .33). Approximately 10% of the genetic influences on reported life events were accounted for by influences shared with anxiety sensitivity and environmental sensitivity. CONCLUSION: Differences in how individuals process the contextual aspects of the environment or interpret their own physical and emotional response to environmental stimuli may be one mechanism through which genetic liability influences the subjective experience of life events.

Ambulatory percutaneous nephrolithotomy is safe and effective in patients with extended selection criteria.

INTRODUCTION: Ambulatory percutaneous nephrolithotomy (PCNL) has been limited to highly selected patients. The objective of our study was to compare complication and stone-free rates after ambulatory PCNL in standard selection criteria vs. extended criteria patients. METHODS: We conducted a retrospective review of prospective data on all patients who underwent ambulatory PCNL at one academic center from 2007-2018. Extended criteria patients were defined as one or more of: age >75 years, body mass index (BMI) >30 kg/m2, American Society of Anesthesiologists (ASA) score >2, bilateral stones, solitary kidney, transplant kidney, complete staghorn calculi, stone burden >40 mm, multiple tracts, or prior nephrostomy tubes/stents. Primary outcomes were complication rates (Clavien-Dindo classification) and stone-free rates. RESULTS: We identified 118 patients, of which 92 (78%) met extended criteria. Mean BMI was 31 kg/m2 and 45% were ASA 3 or higher. Mean sum maximum stone diameter was 24 mm. Multiple stones were present in 25%, bilateral stones in 7%, and complete staghorn stones in 4% of patients. There was no difference in complication (12% vs. 18%, p=0.56), emergency department visit (12% vs. 18%, p=0.56), or re-admission (4% vs. 5%, p=1) rates between standard and extended criteria patients, respectively. Of the complications, 85% were Clavien-Dindo grade 1. Stone-free rates were not different between standard (84%) and extended (83%) criteria patients (p=1). No extended criteria variables were associated with complications in multivariable analysis. CONCLUSIONS: Complication and stone-free rates were not different between standard and extended selection criteria patients undergoing ambulatory PCNL. This data indicates that many of the preoperative patient and stone factors that have previously been used as exclusion criteria for ambulatory PCNL are not strictly necessary.

Fear conditioning in women with anorexia nervosa and healthy controls: A preliminary study.

Anorexia nervosa is characterized by anxiety-driven behaviors, such as food avoidance and distressing persistent thoughts about weight gain and body image. The present study used a classical fear conditioning procedure to test the processes of fear acquisition and generalization, extinction, and renewal in patients with anorexia nervosa and healthy controls. An app-based fear conditioning procedure was administered remotely to 64 patients and 60 healthy controls, over two sessions. A human female scream served as the unconditioned stimulus (US) and two neutral shapes were used as either the paired conditioned stimulus (danger cue; CS+) or the unpaired conditioned stimulus (safe cue; CS-). Patients with anorexia nervosa reported greater threat expectancy in response to the danger cue during the extinction and renewal phases and overall higher levels of negative affect throughout the task, compared with controls. Future research is warranted to replicate these findings and highlight the role that anxiety plays in explaining fear conditioning responses in patients with anorexia nervosa. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The association of gender and persistent opioid use following an acute pain event: A retrospective population based study of renal colic.

INTRODUCTION: This study aims to explore gender-related differences in persistent opioid use following an acute pain episode and evaluate potential explanatory variables. METHODS: This retrospective population-based study using administrative databases included all opioid-naïve patients in Ontario with renal colic between 2013 and 2017. The primary outcome was to assess any association between persistent opioid use at 3-6 months by gender. Key confounding covariates and explanatory variables examined included both care- and patient-related factors, specifically past evidence of mental health diagnoses. RESULTS: The dataset of 64,240 males and 37,656 females demonstrated that 8.7% of males and 9.6% of females had evidence of persistent opioid use 3-6 months after presentation (OR 1.11, 95% CI 1.05, 1.17). Females had a higher incidence of mental health services utilization [44.5% vs 29.6% (p<0.001)] and were more likely to be on a provincial disability program [5.1% vs 3.8% (p<0.001)]. Age, income quintile, mental health diagnoses and dose of opioid prescribed were associated with the primary outcome in both genders. On adjusted analysis for multiple confounding and explanatory variables, females were still more likely than males to demonstrate persistent opioid use (OR 1.07, 95% CI 1.01, 1.13) with even more pronounced associations at 1-2 years. INTERPRETATION: After controlling for key covariates, females are at slightly higher risk of demonstrating long term opioid use following an episode of renal colic. Evidence of prior mental health service utilization and acute colic care did not appear to significantly explain these observations.

Large-scale remote fear conditioning: Demonstration of associations with anxiety using the FLARe smartphone app.

OBJECTIVES: We aimed to examine differences in fear conditioning between anxious and nonanxious participants in a single large sample. MATERIALS AND METHODS: We employed a remote fear conditioning task (FLARe) to collect data from participants from the Twins Early Development Study (n = 1,146; 41% anxious vs. 59% nonanxious). Differences between groups were estimated for their expectancy of an aversive outcome towards a reinforced conditional stimulus (CS+) and an unreinforced conditional stimulus (CS-) during acquisition and extinction phases. RESULTS: During acquisition, the anxious group (vs. nonanxious group) showed greater expectancy towards the CS-. During extinction, the anxious group (vs. nonanxious group) showed greater expectancy to both CSs. These comparisons yielded effect size estimates (d = 0.26-0.34) similar to those identified in previous meta-analyses. CONCLUSION: The current study demonstrates that remote fear conditioning can be used to detect differences between groups of anxious and nonanxious individuals, which appear to be consistent with previous meta-analyses including in-person studies.

Crowdfunding in urology: Canadian perspective.

INTRODUCTION: Crowdfunding is becoming an increasingly used resource for patients to cover costs related to medical care. These costs can be related directly to treatments or indirectly to loss of income or travel-related costs. Little is known as to the extent of which crowdfunding is used for urological disease here in Canada. This study offers a first look at the prevalence of crowdfunding for urological disease and the factors surrounding its use. METHODS: In January 2020, we queried the GoFundMe internal search engine for fundraising campaigns regarding urological ailments. Results were categorized according to the major organs of urological disease. RESULTS: Crowdfunding campaigns are very prevalent within several areas of urology. Prostate cancer and chronic kidney disease represent the most frequent reason for campaigns. Fundraising goals and actual funds raised for malignant disease were significantly more than for benign disease. Interestingly, there was a significant portion of crowdfunding campaigns to cover costs for non-conventional treatments and transplant tourism. CONCLUSION: Crowdfunding use to help cover direct and indirect costs of medical care is becoming increasingly apparent through several facets of medicine. This study shows that this statement holds true when looking at patients with urological disease in Canada. As urologists, we need to be aware of this trend, as it highlights the often-unforeseen financial burdens experienced by our patients.

Measuring fear: Association among different measures of fear learning.

BACKGROUND AND OBJECTIVES: Fear conditioning paradigms use various measures to assess learned fear, including autonomic arousal responses like skin conductance, and self-reports of both associative (US-expectancies) and evaluative (affective ratings) learning. The present study uses a dimensional approach to examine associations among fear indices directly. METHODS: Seventy-three participants completed a differential fear conditioning experiment, during which a neutral stimulus (CS+) was paired with an electric shock (US), while another stimulus (CS-) was never paired with the shock (partially instructed fear acquisition). Ten minutes later, both stimuli were presented without any shocks (fear extinction). Skin conductance responses and US-expectancy ratings were recorded during each phase, while self-reported negative affect was assessed for each CS at the end of extinction. RESULTS: Results showed a positive association among US-expectancy ratings and skin conductance responses during acquisition and early extinction. US-expectancy ratings during overall extinction were positively associated with post-extinction negative affect. LIMITATIONS: The lack of affective ratings post-acquisition may have obscured associations between associative and evaluative learning indices. CONCLUSIONS: Results provide evidence for the expected correspondence among different indices of associative fear learning. Findings emphasize the need for incorporating both associative and evaluative learning measures in fear conditioning paradigms.

The impact of COVID-19 on the Canadian Kidney Paired Donation program: an opportunity for universal implementation of kidney shipping.

SUMMARY: "Never let a good crisis go to waste." - Sir Winston Churchill.The value of Canada's Kidney Paired Donation program to the population cannot be overstated. Its greatest challenge as a national program, however, is the geographic separation of recipient and matched donor. Representatives from every transplant program in the country have been working toward increased use of kidney shipping in order to diminish the disincentive of donor travel. With transplantation program and travel restrictions in place to minimize the risk of coronavirus disease 2019 (COVID-19), the time to make a full transition from donor travel to the shipment of donor kidneys has clearly arrived.

Canadian Update on Surgical Procedures (CUSP) Urology Group consensus for intraoperative hemostasis during minimally invasive partial nephrectomy.

INTRODUCTION: Partial nephrectomy remains the gold standard in the management of small renal masses. However, minimally invasive partial nephrectomy (MIPN) is associated with a steep learning curve, and optimal, standardized techniques for time-efficient hemostasis are poorly described. Given the relative lack of evidence, the goal was to describe a set of actionable guiding principles, through an expert working panel, for urologists to approach hemostasis without compromising warm ischemia or oncological outcomes. METHODS: A three-step modified Delphi method was used to achieve expert agreement on the best practices for hemostasis in MIPN. Panelists were recruited from the Canadian Update on Surgical Procedures (CUSP) Urology Group, which represent all provinces, academic and community practices, and fellowship-and non-fellowship-trained surgeons. Thirty-two (round 1) and 46 (round 2) panellists participated in survey questionnaires, and 22 attended the in-person consensus meeting. RESULTS: An initial literature search of 945 articles (230 abstracts) underwent screening and yielded 24 preliminary techniques. Through sequential survey assessment and in-person discussion, a total of 11 strategies were approved. These are temporally distributed prior to tumor resection (five principles), during tumor resection (two principles), and during renorrhaphy (four principles). CONCLUSIONS: Given the variability in tumor size, depth, location, and vascularity, coupled with limitations of laparoscopic equipment, achieving consistent hemostasis in MIPN may be challenging. Despite over two decades of MIPN experience, limited evidence exists to guide clinicians. Through a three-step Delphi method and rigorous iterative review with a panel of experts, we ascertained a guiding checklist of principles for newly beginning and practicing urologists to reference.

Analgesic prescribing habits and patterns of Canadian chief urology residents: A national survey.

INTRODUCTION: Prior studies have identified significant knowledge gaps in acute and chronic pain management among graduating urology residents as of five years ago. Since then, there has been increasing awareness of the impact of excessive opioid prescribing on long-term narcotic use and development of adverse narcotic-related events. However, it is unclear whether the attitudes and experience of graduating urology residents have changed. We set out to evaluate the attitudes and experience of graduating urology residents in prescribing opioid/non-opioid analgesia for acute (AP), chronic non-cancer (CnC), and chronic cancer (CC) pain. METHODS: Graduating urology residents were surveyed at a review course in 2018. The survey consisted of open-ended and close-ended five-point Likert scale questions. Descriptive statistics, Mann-Whitney U-test, and Student's t-test were performed. RESULTS: A total of 32 postgraduate year-5 (PGY5) urology residents completed our survey (92% response rate). The vast majority agreed that formal training in managing AP/CnC/CC is valuable (91/78/81%). Most find their training in CnC/CC management to be inadequate and are unaware of any opioid prescribing guidelines; 66% never counsel patients on how to dispose of excess opioids. In general, 88% are comfortable prescribing opioids, whereas most are very uncomfortable prescribing cannabis or antidepressants (100% and 78%, respectively). Residents reported the acute pain service as the highest-rated resource for information, and dedicated textbooks the least. CONCLUSIONS: This survey demonstrated that experience in pain management remains variable among urology residents. Knowledge gaps remain, particularly in the management of CC/CnC pain.

Increased risk of new persistent opioid use in pediatric and young adult patients with kidney stones.

INTRODUCTION: Adolescents and young adults are a vulnerable patient population for development of substance use disorder. However, the long-term impact of opioid prescribing in young adult patients with renal colic is not known. Our objective was to describe rates of opioid prescription and identify risk factors for persistent opioid use in patients age 25 years or younger with renal colic from kidney stones. METHODS: Using previously validated, linked administrative databases, we performed a population-based, retrospective cohort study of opioid-naive patients age 25 years or younger with renal colic between July 1, 2013 and September 30, 2017 in Ontario. All family practitioner, urgent care, and specialist visits in the province were captured. Our primary outcome was persistent opioid use, defined as filling a prescription for an opioid between 91 and 180 days after initial visit. Ontario uses a narcotic monitoring system, which captures all opioids dispensed in the province. RESULTS: Of the 6962 patients identified, 56% were prescribed an opioid at presentation and 34% of those were dispensed more than 200 oral morphine equivalents. There was persistent opioid use in 313 (8.1%) patients who filled an initial opioid prescription. In adjusted analysis, those prescribed an opioid initially had a significantly higher risk of persistent opioid use (odds ratio [OR] 1.85; 95% confidence interval [CI] 1.50-2.29) and opioid overdose (OR 3.45; 1.08-11.04). There was a dose-dependent increase in risk of persistent opioid use with escalating initial opioid dose. History of mental illness (OR 1.32; 1.02-1.71) and need for surgery (OR 1.71; 1.24-2.34) were also associated with persistent opioid use. CONCLUSIONS: Among patients with kidney stones age 25 years or younger, filling an opioid prescription after presentation is associated with an increased risk of persistent opioid use 3-6 months later and a higher risk of serious long-term complications, such as opioid overdose.

Risk Factors for Upstaging, Recurrence, and Mortality in Clinical T1-2 Renal Cell Carcinoma Patients Upstaged to pT3a Disease: An International Analysis Utilizing the 8th Edition of the Tumor-Node-Metastasis Staging Criteria.

OBJECTIVE: To investigate risk factors for and outcomes in pathological T3a-upstaging in Renal Cell Carcinoma (RCC), as Tumor-Node-Metastasis staging for T3a RCC was recently revised. METHODS: Multicenter retrospective analysis of patients with clinical T1-T2 RCC, stratified by occurrence of pathologic T3a-upstaging. Primary outcome was recurrence-free survival (RFS). Multivariable analyses (MVA) were conducted for upstaging and recurrence. Kaplan-Meier analysis (KMA) was utilized for RFS and overall survival (OS). RESULTS: We analyzed 2573 patients (1223 RN/1350 PN). Upstaging occurred in 360 (14.0%). On MVA, higher clinical stage was associated with increasing risk of upstaging [cT1a (referent), odds ratio for cT1b, cT2a, and cT2b was 2.6, 6.5, and 14.1, P < .001]. Higher clinical stage at presentation correlated with increasing risk of recurrence in pT3a-upstaged RCC (cT1a upstaged-pT3a [referent], hazard ratio [HR] for cT1b, cT2a, and cT2b upstaged pT3a was 1.16 [P = .729], 3.02 [P = .013], and 4.5 [P = .003]). Perirenal fat (HR 1.6, P = .038) and renal vein (HR 2.2, P = .006) invasion were associated with increased risk of recurrence; type of surgery was not (P = .157). KMA for RFS and OS in pT3a-upstaged patients demonstrated differences based on initial clinical stage (5-year PFS for cT1a/b, and cT2 upstaged was 84.5%/72.8%, and 44.7%, P < .001; 5-year OS for cT1 and cT2 upstaged was 83.8% and 63.2%, P < .001). CONCLUSION: Risk of pT3a-upstaging and recurrence in pT3a-upstaged RCC correlates with clinical stage at presentation. Renal vein and perinephric fat invasion were associated with increased risk of recurrence. PN did not increase risk of recurrence and potential of pT3a-upstaging should not deter consideration of PN.

Persistent Opioid Use Among Patients with Urolithiasis: A Population based Study.

BACKGROUND: Urolithiasis can result in acute, short-lived pain for which opioids are often prescribed. The risk of persistent opioid use following an initial presentation for urolithiasis is unknown. OBJECTIVE: To describe rates of opioid prescription and identify risk factors for persistent opioid use among patients with urolithiasis. DESIGN, SETTING, AND PARTICIPANTS: This was a population-based study of all patients diagnosed with urolithiasis in Ontario between 2013 and 2017 using administrative databases. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was persistent opioid use, defined as dispensing of opioids between 91 and 180 d after presentation. Multivariable logistic regression and Cox proportional hazard models were used to identify factors associated with outcomes. RESULTS AND LIMITATIONS: Of 101 896 previously opioid-naïve patients, 66% were prescribed opioids at diagnosis and 41% of those were dispensed more than 200 oral morphine equivalents (OMEs). For those patients prescribed opioids, 9% had continued use. In adjusted analysis, the number of health care visits and having a stone intervention were associated with a higher risk of persistent opioid use (p< 0.0001). Total OME dispensed at presentation was highly associated with persistent use: for >300 OME the odds ratio (OR) was 1.59 (95% confidence interval [CI] 1.41-1.79). Among those who had an intervention, the number and type of procedure were also associated with persistent use: the OR for shockwave lithotripsy compared to ureteroscopy was 1.65 (95% CI 1.42-1.92). This study is limited by the accuracy of the diagnostic and procedural administrative codes available. CONCLUSIONS: The majority of urolithiasis patients were prescribed opioids and 9% of previously opioid-naïve patients exhibited persistent opioid use 91-180 d after their initial urolithiasis visit. PATIENT SUMMARY: In this study we found that 9% of patients prescribed opioids at presentation for kidney stones filled an additional prescription 3-6 mo later. Risk factors for this continued use included a higher dose of opioids prescribed in the initial period and the type of kidney stone surgery.