The impact of heat on kidney stone presentations in South Carolina under two climate change scenarios.

The risk of kidney stone presentations increases after hot days, likely due to greater insensible water losses resulting in more concentrated urine and altered urinary flow. It is thus expected that higher temperatures from climate change will increase the global prevalence of kidney stones if no adaptation measures are put in place. This study aims to quantify the impact of heat on kidney stone presentations through 2089, using South Carolina as a model state. We used a time series analysis of historical kidney stone presentations (1997-2014) and distributed lag non-linear models to estimate the temperature dependence of kidney stone presentations, and then quantified the projected impact of climate change on future heat-related kidney stone presentations using daily projections of wet-bulb temperatures to 2089, assuming no adaptation or demographic changes. Two climate change models were considered-one assuming aggressive reduction in greenhouse gas emissions (RCP 4.5) and one representing uninibited greenhouse gas emissions (RCP 8.5). The estimated total statewide kidney stone presentations attributable to heat are projected to increase by 2.2% in RCP 4.5 and 3.9% in RCP 8.5 by 2085-89 (vs. 2010-2014), with an associated total excess cost of ~ $57 million and ~ $99 million, respectively.

Cost-effectiveness of Retrograde Intrarenal Surgery, Standard and Mini Percutaneous Nephrolithotomy, and Shock Wave Lithotripsy for the Management of 1-2cm Renal Stones.

OBJECTIVE: To perform a cost-effectiveness evaluation comparing the management options for mid-size (1-2cm) renal stones including percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and shockwave lithotripsy (SWL). METHODS: A Markov model was created to compare cost-effectiveness of PCNL, mini-PCNL, RIRS, and SWL for 1-2cm lower pole (index patient 1) and PCNL, RIRS, and SWL for 1-2 cm non-lower pole (index patient 2) renal stones. A literature review provided stone free, complication, retreatment, secondary procedure rates, and quality adjusted life years (QALYs). Medicare costs were used. The incremental cost-effectiveness ratio (ICER) was compared with a willingness-to-pay(WTP) threshold of $100,000/QALY. One-way and probabilistic sensitivity analyses were performed. RESULTS: At 3 years, costs for index patient 1 were $10,290(PCNL), $10,109(mini-PCNL), $5,930(RIRS), and $10,916(SWL). Mini-PCNL resulted in the highest QALYs(2.953) followed by PCNL(2.951), RIRS(2.946), and SWL(2.943). This translated to RIRS being most cost-effective followed by mini-PCNL(ICER $624,075/QALY) and PCNL(ICER $946,464/QALY). SWL was dominated with higher costs and lower effectiveness. For index patient 2, RIRS dominated both PCNL and SWL. For index patient 1: mini-PCNL and PCNL became cost effective if cost ≤$5,940 and ≤$5,390, respectively. SWL became cost-effective with SFR ≥75% or cost ≤$1,236. On probabilistic sensitivity analysis, the most cost-effective strategy was RIRS in 97%, mini-PCNL in 2%, PCNL in 1%, and SWL in 0% of simulations. CONCLUSION: For 1-2cm renal stones, RIRS is most cost-effective. However, mini and standard PCNL could become cost-effective at lower costs, particularly for lower pole stones.

Comparing extracorporeal shock wave lithotripsy and ureteroscopy laser lithotripsy for treatment of urinary stones smaller than 2 cm: a cost-utility analysis in the Spanish clinical setting.

PURPOSE: To analyze the efficiency and cost-utility profile of ureteroscopy versus shock wave lithotripsy for treatment of reno-ureteral stones smaller than 2 cm. METHODS: Patients treated for urinary stones smaller than 2 cm were included in this study (n = 750) and divided into two groups based on technique of treatment. To assess the cost-utility profile a sample of 48 patients (50% of each group) was evaluated. Quality of life survey (Euroqol 5QD-3L) before-after treatment was applied, Markov model was designed to calculate quality of life in each status of the patients (stone or stone-free with and without double-J stent) and to estimate the incremental cost-utility. Monte carlo simulation was conducted for a probabilistic sensitivity analysis. Chi-square was used for comparing qualitative variables and T student's for continuous variables. RESULTS: Shock wave lithotripsy group had 408 (54.4%) and ureteroscopy group had 342 (45.6%) patients. Of them, 56.3% were treated for renal stones and 43.7% for ureteral stones. Ureteroscopy produced slightly higher overall quality of patients' life, but produced a significant higher overall cost per quality-adjusted life year (QALY) than shock wave lithotripsy, exceeding the cost-utility threshold (20,000€/QALY). Sensitivity analysis confirmed results in 93.65% of cases. Difference was maintained in subgroup analysis (ureteral vs renal stones). CONCLUSIONS: Results suggest that in our clinical setting shock wave lithotripsy has better cost-utility profile than ureteroscopy for treatment of reno-ureteral stones less than 2 cm, but excluding waiting times, in ideal clinical setting, ureteroscopy would have better cost-utility profile than shock wave lithotripsy.

Análisis comparativo de costes directos e indirectos de dos técnicas mínimamente invasivas, para el tratamiento de la litiasis renoureteral menor de 2 cm / Comparative analysis of direct and indirect costs of two minimally invasive techniques for the treatment of renal/ureteral calculi smaller than 2 cm

OBJETIVO: Analizar de forma comparativa los costes indirectos y directos de dos técnicas mínimamente invasivas (litotricia extracorpórea (LEOC) vs. ureterorrenoscopia-láser holmium (URS/RIRS)) para el tratamiento de la litiasis reno-ureteral menor de 2 cm. MATERIAL Y MÉTODOS: Estudio prospectivo y comparativo, no aleatorizado de 84 pacientes tratados por litiasis reno-ureteral menor de 2 cm entre enero y diciembre de 2016. De estos, 38 (45,67%) se trataron con LEOC (18 litiasis renales y 20 litiasis ureterales) y 46 (54,32%) con URS/RIRS (22 litiasis renal y 24 litiasis ureteral). Un total de 19 (41,3%) pacientes estaban activos laboralmente en el grupo de URS/RIRS y 15 (39,5%) pacientes en el grupo de LEOC. Las variables analizadas fueron sexo, edad, número y tamaño de las litiasis, días de baja laboral debido al tratamiento, estimación del coste indirecto por la pérdida de productividad laboral y el coste directo del tratamiento aplicado incluyendo el seguimiento (número total de procedimientos, procedimientos auxiliares, visitas y pruebas diagnósticas). Para la estimación del coste indirecto se empleó la Encuesta de Estructura Salarial 2015 (INE). Además, también se utilizó el cuestionario «Work Productivity and Activity Impairment» (WPAI) para determinar el grado de percepción de pérdida de productividad. RESULTADOS: El número medio de sesiones hasta la resolución de la litiasis fue de 2,57 para el grupo de LEOC y de 1,04 para la URS. El promedio de días de baja laboral en el grupo de la URS fue de 7,16 días, mientras que en el caso de la LEOC fue de 3,18 (p = 0,034). Los costes indirectos totales derivados de la pérdida de productividad fueron de 621,55 € y de 276,05 € para la URS y LEOC, respectivamente. Los costes directos en el grupo de la LEOC fueron de 1.382,9 € y 2.317,71 € en el grupo de la URS. El grado de afectación en el trabajo percibido por los pacientes sometidos a URS fue del 18,88% y del 21,33% en el grupo de LEOC. El grado de afectación para realizar actividades cotidianas fue del 24,44% en URS y del 15% en LEOC. CONCLUSIONES: La LEOC es una técnica que precisa de un mayor número medio de sesiones para la resolución de la litiasis reno-ureteral menor de 2 cm, pero con una menor repercusión en los costes totales y en la percepción del grado de afectación

OBJECTIVE: To perform a comparative analysis of indirect and direct costs of two minimally invasive techniques (extracorporeal shock wave lithotripsy (ESWL) vs. ureteroscopy with holmium laser (URS/RIRS)) for the treatment of renal/ureteral calculi smaller than 2 cm. MATERIAL AND METHODS: Prospective, comparative, non-randomized study of 84 patients treated for kidney stones smaller than 2 cm between January and December 2016. Of these, 38 (45.67%) were treated with ESWL (18 renal lithiasis and 20 ureteral lithiasis) and 46 (54.32%) with URS/RIRS (22 renal lithiasis and 24 ureteral lithiasis). A total of 19 (41.3%) patients in the URS/RIRS group and 15 (39.5%) patients in the ESWL group were actively working before treatment. The variables analyzed were sex, age, number and size of lithiasis, time (days) off from work due to treatment, estimate of indirect cost due to labor productivity loss and direct treatment costs including follow-up (total number of procedures, ancillary care, visits and diagnostic tests). The 2015 Wage Structure Survey (INE) was used to estimate the indirect cost. In addition, the «Work Productivity and Activity Impairment» (WPAI) questionnaire was also used to determine the level of perceived productivity loss. RESULTS: The mean number of sessions until lithiasis resolution was achieved was 2.57 for the ESWL group and 1.04 for the URS. The mean number of days off from work in the URS group was 7.16 days and 3.18 (p = 0.034) in the ESWL group. The total indirect costs resulting from productivity loss were EUR 621.55 and EUR 276.05 for the URS and ESWL, respectively. Direct costs in the ESWL group were EUR 1,382.9 and EUR 2,317.71 in the URS group. The level of work impairment perceived by patients undergoing URS was 18.88% and 21.33% in the ESWL group. The degree of impairment for performing activities of daily living was 24.44% in the URS and 15% in ESWL. CONCLUSIONS: The ESWL technique requires a higher number of sessions for the resolution of kidney stones under 2 cm, but it has a lower impact on total costs and on the perceived degree of affectation

Comparative analysis of direct and indirect costs of two minimally invasive techniques for the treatment of renal/ureteral calculi smaller than 2 cm. / Análisis comparativo de costes directos e indirectos de dos técnicas mínimamente invasivas, para el tratamiento de la litiasis renoureteral menor de 2 cm.

OBJECTIVE: To perform a comparative analysis of indirect and direct costs of two minimally invasive techniques (extracorporeal shock wave lithotripsy (ESWL) vs. ureteroscopy with holmium laser (URS/RIRS)) for the treatment of renal/ureteral calculi smaller than 2 cm. MATERIAL AND METHODS: Prospective, comparative, non-randomized study of 84 patients treated for kidney stones smaller than 2 cm between January and December 2016. Of these, 38 (45.67%) were treated with ESWL (18 renal lithiasis and 20 ureteral lithiasis) and 46 (54.32%) with URS/RIRS (22 renal lithiasis and 24 ureteral lithiasis). A total of 19 (41.3%) patients in the URS/RIRS group and 15 (39.5%) patients in the ESWL group were actively working before treatment. The variables analyzed were sex, age, number and size of lithiasis, time (days) off from work due to treatment, estimate of indirect cost due to labor productivity loss and direct treatment costs including follow-up (total number of procedures, ancillary care, visits and diagnostic tests). The 2015 Wage Structure Survey (INE) was used to estimate the indirect cost. In addition, the «Work Productivity and Activity Impairment¼ (WPAI) questionnaire was also used to determine the level of perceived productivity loss. RESULTS: The mean number of sessions until lithiasis resolution was achieved was 2.57 for the ESWL group and 1.04 for the URS. The mean number of days off from work in the URS group was 7.16 days and 3.18 (p = 0.034) in the ESWL group. The total indirect costs resulting from productivity loss were EUR 621.55 and EUR 276.05 for the URS and ESWL, respectively. Direct costs in the ESWL group were EUR 1,382.9 and EUR 2,317.71 in the URS group. The level of work impairment perceived by patients undergoing URS was 18.88% and 21.33% in the ESWL group. The degree of impairment for performing activities of daily living was 24.44% in the URS and 15% in ESWL. CONCLUSIONS: The ESWL technique requires a higher number of sessions for the resolution of kidney stones under 2 cm, but it has a lower impact on total costs and on the perceived degree of affectation.

Does Early Retrograde Intrarenal Surgery Improve the Cost-Effectiveness of Renal Stone Management?

PURPOSE: This study aimed to evaluate the cost-effectiveness of treatment with retrograde intrarenal surgery (RIRS) versus repeated shock wave lithotripsy (SWL) in patients with renal calculi. MATERIALS AND METHODS: The non-retreatment rates (NRRs) and their respective real-world costs for RIRS and SWL were derived through retrospective analysis of health insurance claims data from 2015 to 2017. Decision tree modeling was performed to demonstrate the cost-effectiveness of RIRS. Furthermore, sensitivity analysis was performed to examine the robustness of the results. RESULTS: Analysis of the obtained data showed that NRRs of single SWL ranged from 46% to 56%, whereas NRRs of single RIRS ranged from 75% to 93%. Introducing RIRS early in the treatment sequence was observed to be favorable for the reduction of overall failure (overall NRR, 0.997) compared to the results of repeated SWL (overall NRR, 0.928). The implementation of decision tree modeling revealed that the cost per retreatment-avoided increased with the introduction of RIRS at an earlier time (first line, second line, third line, fourth line: 18640 USD, 10376 USD, 4294 USD, 3377 USD, respectively). Probabilistic modeling also indicated that the introduction of RIRS as the first line of treatment was least likely to be cost-effective, when compared to other options of introducing RIRS as the second, third, or fourth line of treatment. CONCLUSION: Performing RIRS as early as possible can be recommended for eligible patients to reduce the overall failure, even if it is not as cost-effective as performing RIRS later.

Evaluation of the economic burden of kidney stone disease in the UK: a retrospective cohort study with a mean follow-up of 19 years.

OBJECTIVE: To estimate the cost of kidney stone disease (KSD) in England. PATIENTS AND METHODS: We conducted a retrospective cohort study of patients with KSD, referred to a metabolic stone clinic between 1990 and 2007 using electronic records of patients with KSD in a tertiary referral centre, to determine cost using UK National Health Service (NHS) tariff, with subsequent extrapolation to the entire England population. Those with no documentation and <5 years follow-up were excluded. The outcome measure was calculation of cost (as per 2018 NHS tariff) presented as lower and higher estimates for: per episode; total within the cohort; and estimation of initial, 5-,10- and 15-year costs for the cohort and total population in England. Linear regression was used to examine for significant predictors of per episode and total cost. RESULTS: A total of 781 patients were included in the study after 1000 records were screened for inclusion, with a mean follow-up of 19 years. The mean (SD) overall costs per episode were between £1277 (1724) and £2887 (2492). Total initial costs for the cohort were between £950 842 and £2 336 442, rising to between £1.43 million and £3.02 million at 15 years of follow-up. Estimated cost in 2010 in England alone was between £190 million and £324 million. CONCLUSION: KSD is a costly disease, comparable to the combined cost of prostate and bladder cancer in UK.

Flexible ureteroscopy: reuse? Or is single use the new direction?

PURPOSE OF REVIEW: Single-use flexible ureteroscopes (su-fURS) aim at overcoming the main limitations of conventional reusable ureteroscopes in terms of acquisition and maintenance costs, breakages, and reprocessing. However, little data exist to date regarding the superiority of su-fURS at this regard. We aimed to perform a systematic literature review on available su-fURS performance with a focus on clinical data for all articles in the last 10 years. RECENT FINDINGS: To date, more than 10 different su-fURS are available on the market, with different characteristics and performance. Some of these devices have top-level features, almost catching up with those observed in reusable flexible ureteroscopes. Clinical evidence is mainly available only for two models, LithoVue and Uscope PU3022, and to date it is not strong enough to support routine adoption and use of su-fURS, with a consequent lack of consensus of specific clinical indications. Cost-effectiveness analyses seem to indicate an economic disadvantage in the routine adoption of su-fURS. Environmental issues related to the use of su-fURS also remain to be inquired and addressed. SUMMARY: Since their introduction, su-fURS have gained widespread popularity. Despite their ability at addressing reusable ureteroscope limitations, high-cost and a substantial lack of evidence are still limiting their routine adoption.

Assessing Cost-Effectiveness of New Technologies in Stone Management.

Diagnosis, treatment, and follow-up are all influential in determining the overall cost to the health care system for kidney stones. New innovations in the field of nephrolithiasis have been abundant, including disposable ureteroscopes, ultrasound-guided approaches to percutaneous nephrolithotomy, and advanced laser lithotripters. Identifying cost-effective treatment strategies encourages practitioners to be thoughtful about providing value-based high-quality care and remains on important principle in the treatment of urinary stone disease.

Socioeconomic Disparities in the Acute Management of Stone Disease in the United States.

INTRODUCTION: Patients admitted to the hospital with an acute, noninfected episode of urolithiasis are candidates for medical expulsive therapy, ureteral stent placement, or upfront ureteroscopy (URS). We sought to assess socioeconomic factors influencing treatment decisions in managing urolithiasis and to determine differences in outcomes based on treatment modality. MATERIALS AND METHODS: The Healthcare Cost and Utilization Project State Inpatient Database, State Ambulatory Surgery and Services Database, and State Emergency Department Database for California from 2007 to 2011 and for Florida from 2009 to 2014 were utilized. Patients who were admitted to the hospital with a primary diagnosis of kidney or ureteral stone were identified. The initial treatment modality utilized was assessed and factors that influenced that decision were analyzed. Multivariate logistic regression model was fit to determine factors independently associated with upfront URS. Lastly, outcomes of noninfected patients who underwent stent alone vs URS were compared. RESULTS: We identified 146,199 patients who had an inpatient admission with urolithiasis. Overall, 45% of patients had no intervention at the time of their evaluation. Of the 55% of patients who underwent surgical intervention, 42% underwent stent alone, 44% underwent upfront URS, 1% had a PCN tube placement, 8% underwent extracorporeal shockwave lithotripsy, while 5% underwent PCNL. On multivariate logistic regression model, minorities, younger patients, publicly uninsured patients, more comorbid patients, those admitted on the weekends, and those admitted to an academic institution had significantly lower odds of undergoing upfront URS. Secondary analysis demonstrated clinical and economic advantages of upfront URS vs stent alone in eligible patients. CONCLUSION: Upfront URS is an overlooked procedure that has clinical and cost-saving implications. Unfortunately, minorities, publicly insured patients, and those admitted on the weekend are less likely to undergo upfront URS, a disparity that should be addressed by urologist.

Changing Trends in the Treatment of Nephrolithiasis in the Real World.

INTRODUCTION: Changes in the surgical treatment of nephrolithiasis, owing to recent technical advances and innovations, have made treatments more effective and less invasive. In this retrospective, observational cohort study, we identified the changing trends in the treatment of nephrolithiasis. MATERIALS AND METHODS: We included patients with newly diagnosed nephrolithiasis who received any treatment in the United States, including extracorporeal shockwave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), and open surgery, from January 2007 to December 2014. Demographic factors, such as age, sex, region, surgical treatment type, and cost data, were analyzed. RESULTS: The median age of patients at treatment was 52 years, and the ratio of men and women was similar. There were definite changes in the trends of all treatment modalities (p < 0.01). Both the number and percentage tended to increase for RIRS, whereas for SWL, the number increased, but the percentage showed a steady decrease. In PCNL, both number and percentage increased to a minor degree. The overall cost of nephrolithiasis treatments during the study period nearly doubled (from $30,998,726 to $57,310,956). The number of treatments and average cost per treatment increased annually for each treatment modality. RIRS was the least expensive; the other procedures in decreasing order of their mean costs were as follows: SWL, PCNL, and open surgery. CONCLUSIONS: There was a gradual but constant change in treatment trends of nephrolithiasis, with an increasing trend for RIRS and a decreasing trend for SWL. Although PCNL has relatively invasive characteristics, it is still in steady demand.

Factors Associated with Regional Adoption of Ureteroscopy in California from 2005 to 2016.

PURPOSE: To explore regional adoption of ureteroscopy (URS) over extracorporeal shockwave lithotripsy (SWL) in the state of California (CA) and to identify factors associated with this adoption over time. MATERIALS AND METHODS: We used the California Office of Statewide Health Planning and Development (OSHPD) public data to identify URS and SWL procedures performed for renal and ureteral stones from 2005 to 2016. The level of analysis was the region wherein each procedure was performed, defined by the 19 CA labor market regions. OSHPD data were supplemented with the Area Health Resource File to provide information on regional characteristics. Generalized linear regression was used to determine procedural rates adjusted for age, gender and race. Choropleth time series maps were used to illustrate adoption of URS by region over time. RESULTS: A total of 328,795 URS and SWL procedures were identified from 2005 to 2016. The number of URS procedures surpassed the number of SWL procedures in 2011. Fourteen regions became URS predominant by 2016 and were characterized as having a higher per capita income, higher percentages with a college education and lower percentage of female heads-of-household (all p-values <0.05). A higher percentage of patients in these regions were male and had private or Medicare insurance (p = 0.03 for both). CONCLUSIONS: From 2005 to 2016, most CA regions adopted URS as the primary renal and ureteral stone management strategy. These regions demonstrated characteristics of higher socioeconomic status compared to regions that remained SWL predominant. A better understanding of such differences in practice patterns will allow urologists to better negotiate for the capital expenditures required to conform to evolving standards of care and allow patients the ability to make more informed decisions on where they receive care.

Disproportionate Use of Inpatient Care by Older Adults With Kidney Stones.

OBJECTIVE: To describe variation in utilization and costs of inpatient care for patients with kidney stones, examining associations with older age. MATERIALS AND METHODS: Using the Nationwide Inpatient Sample we examined inpatient discharges with stone diagnoses from 2007 to 2011. We examined length of stay, hospitalization cost, and postdischarge care utilization using multivariable regression to identify associations between patient/hospital characteristics and resource. RESULTS: An estimated 1.7 million hospital discharges for stone disease occurred during the study period. Median length of stay was 2.1 days with a median cost of $6300. Hospital use was substantially higher among persons ≥65 years old (older adults) as compared to those aged 18-64 (younger adults): median length of stay was 3.1 days, with 25% staying more than 5.9 days. Older adults were significantly more likely to utilize home health (odds ratio [OR] 3.6) or skilled nursing (OR 5.0) after discharge. Older adults accounted for 1 in 3 hospital discharges, 40% of costs, and half of postdischarge care utilization. They were more likely to be septic during hospitalization (OR 1.8) which doubled costs per episode, but less likely to receive surgery (OR 0.93). CONCLUSION: While historically at lower risk for kidney stones compared to younger adults, older adults utilizing inpatient care account for a disproportionate share of the economic burden of disease. Utilization is higher for older adults across multiple dimensions, including hospital costs, length of stay, and postdischarge care. These findings suggest that efforts to understand and mitigate the impact of kidney stones on this vulnerable population are required.

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

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.

Understanding the costs of flexible ureteroscopy.

Ureteroscopy (URS) is the first line treatment for the majority of symptomatic renal and ureteral stones. This review summarizes the current literature on the costs associated with URS. A high initial investment is required for scope acquisition. Once purchased, maintenance and repair costs continue to accrue. Durability of the scopes is an important consideration as more durable scopes will remain functional for longer and thus have lower overall repair costs. Currently available, newer generation scopes appear highly durable compared to their predecessors. Ancillary equipment, mostly disposable items represent the highest per procedure cost of URS. Despite these costs, URS remains highly profitable. However, it is also efficacious demonstrating superior cost-effectiveness with higher stone free rates at a lower cost relative to shock wave lithotripsy.

Cost Analysis of the STONE Randomized Trial: Can Health Care Costs be Reduced One Test at a Time?

BACKGROUND: Decreasing the use of high-cost tests may reduce health care costs. OBJECTIVE: To compare costs of care for patients presenting to the emergency department (ED) with suspected kidney stones randomized to 1 of 3 initial imaging tests. RESEARCH DESIGN: Patients were randomized to point-of-care ultrasound (POC US, least costly), radiology ultrasound (RAD US), or computed tomography (CT, most costly). Subsequent testing and treatment were the choice of the treating physician. SUBJECTS: A total of 2759 patients at 15 EDs were randomized to POC US (n=908), RAD US, (n=893), or CT (n=958). Mean age was 40.4 years; 51.8% were male. MEASURES: All medical care documented in the trial database in the 7 days following enrollment was abstracted and coded to estimate costs using national average 2012 Medicare reimbursements. Costs for initial ED care and total 7-day costs were compared using nonparametric bootstrap to account for clustering of patients within medical centers. RESULTS: Initial ED visit costs were modestly lower for patients assigned to RAD US: $423 ($411, $434) compared with patients assigned to CT: $448 ($438, $459) (P<0.0001). Total costs were not significantly different between groups: $1014 ($912, $1129) for POC US, $970 ($878, $1078) for RAD US, and $959 ($870, $1044) for CT. Hospital admissions contributed over 50% of total costs, though only 11% of patients were admitted. Mean total costs (and admission rates) varied substantially by site from $749 to $1239. CONCLUSIONS: Assignment to a less costly test had no impact on overall health care costs for ED patients. System-level interventions addressing variation in admission rates from the ED might have greater impact on costs.

Comparison of efficacy of laser lithotripter with ultrasonic lithotripter in mini percutaneous nephrolithotomy.

OBJECTIVE: The aim of the study was to compare the efficacy of the laser lithotripter with the ultrasonic lithotripter in mini percutaneous nephrolithotomy (miniperc). MATERIAL AND METHODS: From June 2013 to January 2014; medical records of 77 consecutive patients who underwent miniperc operation were retrospectively evaluated. Ultrasonic lithotripter was used in 22 patients (Group 1), while laser was used in 55 patients. In the laser group, 22 patients were randomly selected who had same characteristics compared to group 1 (Group 2). Success rate, total operative time, complications according to modified Clavien classification, fluoroscopy time, haemoglobin drop, hospital stays and cost analysis were assessed. Success rates were evaluated on the second postoperative day and after the first month. RESULTS: Total operative time (p = 0.635) and fluoroscopy time (p = 0.248) were not significantly different between the two groups. In the laser group, the success rate (81.8%) was notably more than in the ultrasonic lithotripter group (68.2%) but there was no statistically significance (p = 0.296). Ten reusable ultrasonic probe were used for 22 patients, due to thinness and sensitiveness of the probe. Conversely, one single laser fiber (550 micron) was used for 22 patients. When the cost analysis of lithotripsy was considered, the cost per case was 190 dollar in group 1 and 124 dollar in group 2. (p = 0.154) Complication rate, hospital stay and haemoglobin drop were similar in both groups. CONCLUSION: Laser lithotripsy seems to be more cost effective than ultrasonic lithotripsy for miniperc but larger number of patients are required to confirm this estimation.

Unsuccessful Medical Expulsive Therapy: A Cost to Waiting?

OBJECTIVE: To compare clinical outcomes between patients with ureteral stones who underwent an unsuccessful trial of medical expulsive therapy (MET) and patients who did not attempt MET. METHODS: We reviewed the clinical records of all potential candidates for MET who were referred from the emergency department to a subspecialty stone clinic. RESULTS: Of 348 potential candidates, 133 patients (38%) went directly to surgery (NMET) and 215 patients (62%) initiated MET. In the latter group, MET was unsuccessful in 45 patients (21%) (UMET). Stone symptoms were the primary rationale for surgery in 20 (44%) UMET patients and 69 (52%) NMET patients. The UMET patients were more likely to be younger and have smaller, more distal stones than NMET patients. All stones were cleared by ureteroscopy. The average interval from stone clinic assessment to surgery was longer in the UMET patients (17 days) than in the NMET patients (1 day; P <.001). The UMET patients underwent more preoperative computed-tomography scans (2.1) than did the NMET patients (1; P <0.001). There were no differences between the 2 groups in the residual stone burden, pre- or postoperative repeat visits to the emergency department, or repeat surgery. CONCLUSION: In this population, we did not observe any detrimental impact of an unsuccessful trial of MET (beyond the additional time and imaging costs). If more confident and effective symptom control could be achieved, expansion of utilization and duration of MET may be a path to improved patient outcomes and cost control.

Use of the National Health and Nutrition Examination Survey to calculate the impact of obesity and diabetes on cost and prevalence of urolithiasis in 2030.

BACKGROUND: The prevalence of urolithiasis and its risk factors such as obesity and diabetes have increased over time. OBJECTIVE: Determine the future cost and prevalence of kidney stones using current and projected estimates for stones, obesity, diabetes, and population rates. DESIGN, SETTING, AND PARTICIPANTS: The stone prevalence in 2000 was estimated from the National Health and Nutrition Examination Survey (NHANES) 1988-1994 and 2007-2010. The cost per percentage prevalence of stones in 2000, calculated using Urologic Diseases in America Project data, was used to estimate the annual cost of stones in 2030, adjusting for inflation and increases in population, stone prevalence, obesity and diabetes rates. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was prevalence and cost of stones in 2030. The secondary outcomes were the impact of obesity and diabetes on these values, calculated using odds ratios for stones by body mass index and diabetes status. RESULTS AND LIMITATIONS: The annual cost of stone disease in 2000, adjusted for inflation to 2014 US dollars, was approximately $2.81 billion. After accounting for increases in population and stone prevalence from 2000, the estimated cost of stones in 2007 in 2014 US dollars was $3.79 billion. Future population growth alone would increase the cost of stone disease by $780 million in 2030. Based on projected estimates for 2030, obesity will independently increase stone prevalence by 0.36%, with an annual cost increase of $157 million. Diabetes will independently increase stone prevalence by 0.72%, associated with a cost increase of $308 million annually by 2030. NHANES data, however, capture patient self-assessment rather than medical diagnosis, which is a potential bias. CONCLUSIONS: The rising prevalence of obesity and diabetes, together with population growth, is projected to contribute to dramatic increases in the cost of urolithiasis, with an additional $1.24 billion/yr estimated by 2030. PATIENT SUMMARY: Obesity, diabetes, and population rates will contribute to an estimated $1.24 billion/yr increase in the cost of kidney stones by 2030.

Study of Tomography Of Nephrolithiasis Evaluation (STONE): methodology, approach and rationale.

BACKGROUND: Urolithiasis (kidney stones) is a common reason for Emergency Department (ED) visits, accounting for nearly 1% of all visits in the United States. Computed tomography (CT) has become the most common imaging test for these patients but there are few comparative effectiveness data to support its use in comparison to ultrasound. This paper describes the rationale and methods of STONE (Study of Tomography Of Nephrolithiasis Evaluation), a pragmatic randomized comparative effectiveness trial comparing different imaging strategies for patients with suspected urolithiasis. METHODS: STONE is a multi-center, non-blinded pragmatic randomized comparative effectiveness trial of patients between ages 18 and 75 with suspected nephrolithiasis seen in an ED setting. Patients were randomized to one of three initial imaging examinations: point-of-care ultrasound, ultrasound performed by a radiologist or CT. Participants then received diagnosis and treatment per usual care. The primary aim is to compare the rate of severe SAEs (Serious Adverse Events) between the three arms. In addition, a broad range of secondary outcomes was assessed at baseline and regularly for six months post-baseline using phone, email and mail questionnaires. RESULTS: Excluding 17 patients who withdrew after randomization, a total of 2759 patients were randomized and completed a baseline questionnaire (n=908, 893 and 958 in the point-of-care ultrasound, radiology ultrasound and radiology CT arms, respectively). Follow-up is complete, and full or partial outcomes were assessed on over 90% of participants. CONCLUSIONS: The detailed methodology of STONE will provide a roadmap for comparative effectiveness studies of diagnostic imaging conducted in an ED setting.