Cost-Utility Analysis of Treatment Algorithms for Moderate Grade Vesicoureteral Reflux Using Markov Models

Cost-Effectiveness of Screening Ultrasound after a First, Febrile Urinary Tract Infection in Children Age 2-24 Months

OBJECTIVE

To estimate the cost-effectiveness of routine, screening renal bladder ultrasound (RBUS) for children age 2-24 months after a first febrile urinary tract infection (UTI), as recommended by the American Academy of Pediatrics.

STUDY DESIGN

We developed a decision analytic model that simulates a population of children after a first febrile UTI. The model incorporates the diagnostic utility of RBUS to detect vesicoureteral reflux and genitourinary anomalies. We adopted a health-system perspective, 5-year horizon, and included 1-way and 2-way sensitivity analyses. Costs were inflated to 2018 US dollars, and our model incorporated a 3% discounting rate. We compared routine RBUS after first, febrile UTI compared with routine RBUS after second UTI (ie, control arm). Our main outcomes were recurrent UTI rate and incremental cost per quality-adjusted life-year (QALY).

RESULTS

Among children 2-24 months after a first febrile UTI, RBUS had an overall accuracy (true positives + true negatives) of 64.4%. The recurrent UTI rate in the intervention arm was 19.9% compared with 21.0% in the control arm. Thus, 91 patients would need to be screened with RBUS to prevent 1 recurrent UTI. RBUS increases QALYs by +0.0002 per patient screened, corresponding to an incremental cost-effectiveness ratio of $803 000/QALY gained. In the RBUS arm, 20.6% of children would receive unnecessary voiding cystourethrograms compared with 12.2% of children in the control group.

CONCLUSIONS

Screening RBUS after a first, febrile UTI in children age 2-24 months does not meet cost-effectiveness guidelines. Our findings support deferred screening until a second UTI.

Cost-Utility of Antimicrobial Prophylaxis for Treatment of Children With Vesicoureteral Reflux

Objective: Antimicrobial prophylaxis for children with vesicoureteral reflux (VUR) reduces recurrences of urinary tract infection (UTI) but requires daily antimicrobials for extended periods. We used a cost-utility model to evaluate whether the benefits of antimicrobial prophylaxis outweigh its risks and, if so, to investigate whether the benefits and risks vary according to grade of VUR. Methods: We compared the cost per quality-adjusted life-year (QALY) gained in four treatment strategies in children aged <6 years diagnosed with VUR after a first UTI, considering these treatment strategies: (1) prophylaxis for all children with VUR, (2) prophylaxis for children with Grade III or Grade IV VUR, (3) prophylaxis for children with Grade IV VUR, and (4) no prophylaxis. Costs and effectiveness were estimated over the patient's lifetime. We used $100,000/QALY gained as the threshold for considering a treatment strategy cost effective. Results: Based on current data and plausible ranges to account for data uncertainty, prophylaxis of children with Grades IV VUR costs $37,903 per QALY gained. Treating children with Grade III and IV VUR costs an additional $302,024 per QALY gained. Treating children with all grades of VUR costs an additional $339,740 per QALY gained. Conclusions: Treating children with Grades I, II, and III VUR with long-term antimicrobial prophylaxis costs substantially more than interventions typically considered economically reasonable. Prophylaxis in children with Grade IV VUR is cost effective.

Cost-effectiveness of antimicrobial prophylaxis for children in the RIVUR trial

PURPOSE

We evaluated the cost-effectiveness of antimicrobial prophylaxis to prevent recurrent UTIs in children with vesicoureteral reflux based on the RIVUR trial.

MATERIALS AND METHODS

A decision tree model compared strategies of antimicrobial prophylaxis vs. placebo in children with reflux using results from the RIVUR trial. Risk reduction was 50% based on intention to treat analysis. Costs were based on Medicare reimbursement and data in literature. The model incorporated costs of medications, imaging and complications such as pyelonephritis, likelihood of surgery and loss of work. One- and two-way sensitivity analyses were performed evaluating the effect of changing variables on the cost-effectiveness of antibiotic prophylaxis in preventing recurrent UTIs.

RESULTS

Mean costs were higher for treatment vs. placebo at $3092 and $2932, respectively, with 12.7 fewer infections per 100 children. One-way sensitivity analyses showed that antibiotics would be cost equivalent if the yearly medical cost was $386, rate of recurrent UTI increased to 32%, antibiotic risk reduction was 63%, or rate of pyelonephritis in the placebo group was 48%. Two-way analyses modifying antibiotic cost, risk reduction of antibiotics and probability of infection showed areas where antibiotics could be more cost-effective than placebo.

CONCLUSIONS

Antibiotic prophylaxis is associated with marginally higher costs compared with placebo, but significantly fewer infections. A slight decrease in antibiotic cost or increase in recurrent UTIs on placebo may result in prophylaxis being more cost-effective. We recognize that the marginal overall cost in antibiotics may have a substantial impact on the quality of life for the individual patient and family.

Utility Estimation for Pediatric Vesicoureteral Reflux: Methodological Considerations Using an Online Survey Platform

PURPOSE

The advent of online task distribution has opened a new avenue for efficiently gathering community perspectives needed for utility estimation. Methodological consensus for estimating pediatric utilities is lacking, with disagreement over whom to sample, what perspective to use (patient vs parent) and whether instrument induced anchoring bias is significant. We evaluated what methodological factors potentially impact utility estimates for vesicoureteral reflux.

MATERIALS AND METHODS

Cross-sectional surveys using a time trade-off instrument were conducted via the Amazon Mechanical Turk® (https://www.mturk.com) online interface. Respondents were randomized to answer questions from child, parent or dyad perspectives on the utility of a vesicoureteral reflux health state and 1 of 3 "warm-up" scenarios (paralysis, common cold, none) before a vesicoureteral reflux scenario. Utility estimates and potential predictors were fitted to a generalized linear model to determine what factors most impacted utilities.

RESULTS

A total of 1,627 responses were obtained. Mean respondent age was 34.9 years. Of the respondents 48% were female, 38% were married and 44% had children. Utility values were uninfluenced by child/personal vesicoureteral reflux/urinary tract infection history, income or race. Utilities were affected by perspective and were higher in the child group (34% lower in parent vs child, p <0.001, and 13% lower in dyad vs child, p <0.001). Vesicoureteral reflux utility was not significantly affected by the presence or type of time trade-off warm-up scenario (p = 0.17).

CONCLUSIONS

Time trade-off perspective affects utilities when estimated via an online interface. However, utilities are unaffected by the presence, type or absence of warm-up scenarios. These findings could have significant methodological implications for future utility elicitations regarding other pediatric conditions.

Quality assessment of economic evaluation studies in pediatric surgery: a systematic review

PURPOSE

To assess economic evaluation studies (EES) in pediatric surgery and to identify potential factors associated with high-quality studies.

METHODS

A systematic review of the literature using PubMed and Cochrane databases was conducted to identify EES in pediatric surgery published between 1 June 1993 and 30 June 2013. Assessment criteria are derived from the Drummond checklist. A high quality study was defined as a Drummond score ≥7. Logistic regression analysis was used to determine factors associated with high quality studies.

RESULTS

119 studies were included. 43.7% (n=52) of studies were full EES. Cost-effectiveness analysis was the most frequent (61.5%) type of full EES. Only 31.6% of studies had a Drummond score ≥7 and 73% of these were full EES. The factors associated with high quality were identification of costs (OR: 14.08; 95% CI: 3.38-100; p<0.001), estimation of utility value (OR: 8.13; 95% CI: 2.02-43.47; p=0.005) and study funding (OR: 3.50; 95% CI: 1.27-10.10; p=0.02).

CONCLUSION

This review shows that the number and the quality of EES are low despite the increasing number of studies published in recent years. In the current context of budget constraints, our results should encourage pediatric surgeons to focus more on EES.

Estimating utility values for vesicoureteral reflux in the general public using an online tool

INTRODUCTION

Cost-utility analyses are useful to study conditions without a widely accepted treatment algorithm; in pediatric urology, one such condition is vesicoureteral reflux (VUR). A necessary component of cost-utility analyses is to accurately calculate the "utility", a numerical surrogate of quality of life, for various health states. Our aims were to determine utility values for representative VUR health states and to verify the feasibility of a novel online platform for utility elicitation in order to reduce the time and expense of such analyses.

METHODS

A cross-sectional survey of American adults was conducted using the time-trade-off (TTO) method. Respondents were recruited from an online work interface, Amazon's Mechanical Turk (MTurk). Four annualized VUR health states were assessed: VUR treated with/without continuous antibiotic prophylaxis (CAP) and with/without associated febrile urinary tract infection (UTI). A 6-week post-operative scenario following open ureteroneocystostomy was also assessed.

RESULTS

We received 278 survey responses (70% response rate). The respondents were largely between the ages of 25 and 44 (59%), female (60%), and Caucasian (76%). Thirty-seven percent had a college degree, and 44% were parents. Compared with a perfect health state of 1.0, we found mean utilities of 0.87 for VUR, regardless of whether CAP was used or whether UTI was present (p=0.9). The immediate post-operative period following ureteroneocystostomy garnered an annualized utility of 0.94.

CONCLUSIONS

Our data suggest that MTurk-based utility assessment is feasible, and that subjects view the VUR health state as only slightly inferior to perfect health. This includes VUR health states incorporating CAP and febrile UTI.

Occurrence of vesicoureteral reflux in children

AIM

The reported low occurrence of vesicoureteral reflux in the general population seems implausible. We wanted to test the hypothesis that reflux is more common and more independent of urinary-tract infection than has previously been thought.

METHODS

  We tested our hypothesis by analysing the characteristics of 406 consecutive children aged <5years who had been referred for consultation because of urinary-tract infection. Using data on their urine samples, we evaluated the reliability of the urinary-tract infection diagnosis and analysed the frequencies of vesicoureteral reflux and abnormal ultrasound findings in three reliability groups (A: certain urinary-tract infection, B: possible and C: improbable).

RESULTS

 The occurrence of reflux was the same irrespective of the diagnostic reliability of urinary-tract infection (A: 98/276 [36%] versus B: 13/46 [28%] versus C: 9/25 [36%]). Most of the abnormal ultrasound findings (58/71, 80%) were found among patients with a certain diagnosis (Group A).

CONCLUSION

We suggest that vesicoureteral reflux is more common in children even without urinary-tract infection than has been thought previously. The guidelines recommending a search for reflux by means of voiding cystourethrography should be reconsidered.

Injection volumes of dextranomer/hyaluronic acid are increasing in the endoscopic management of vesicoureteral reflux

PURPOSE

Dextranomer/hyaluronic acid (Deflux) has been increasingly used for the treatment of vesicoureteral reflux (VUR). Experience has shown that injecting more volume of material is necessary to achieve greater success. We evaluate trends in the number of vials being used to treat VUR using a multi-institutional database and data from patients treated at our own institution.

METHODS

Children of age 0-19 years in the Pediatric Health Information System (PHIS) database from 2003 to 2008 were extracted with a VUR diagnosis (ICD-9 593.7x) and subureteric injection procedure code (CPT 52327). We identified children with reflux treated with endoscopic injection at Seattle Children's Hospital from 2005 to 2008. Hospital trends of the number of vials used were evaluated using multivariate linear regression.

RESULTS

From 2003 to 2008, we identified 4,078 endoscopic injection procedures in PHIS. There was a 33% increase in the average number of vials used per patient (p < 0.0001) with more than a threefold increase in the number of patients receiving three or more vials per procedure. All institutions increased the average vials used per patient with the most pronounced increase at the highest-volume centers. These trends were also present in the 186 children treated at our own institution.

CONCLUSION

Over the study period there was an increase in the number of vials of dextranomer/hyaluronic acid being used per patient to treat children with VUR. This practice may improve success rates but will increase the cost of treatment due to the inherent expense of the material.

Health Economics of Antibiotics

Antibiotics have made a significant contribution to improving patient health, but policy makers and health care payers are concerned about the costs of antibiotics in addition to their effectiveness. This paper aims to assess the value of antibiotics by examining incremental cost-utility ratios of antibiotics. Evidence was derived from cost-utility analyses of antibiotics included in the Tufts-New England Center Cost-Effectiveness Analysis Registry through September 2009. The analysis included 85 incremental cost-utility ratios from 23 cost-utility analyses. The findings showed that 38.8% of incremental cost-utility ratios related to dominant antibiotics (i.e., more effective and less costly than the comparator); 45.9% referred to antibiotics that improved effectiveness, but also increased costs; and 15.3% related to dominated antibiotics (i.e., less effective and more costly than the comparator). The median ratio was 748 € per quality-adjusted life year. Using threshold values of 20,000 € per quality-adjusted life year and 50,000 € per quality-adjusted life year, the probability that an antibiotic provides value for money was 64% and 67%, respectively. The current evidence base suggests that the majority of antibiotics provide value for money and that antibiotics can aid decision makers to attain further population health improvements, whilst containing pharmaceutical expenditures.

Diagnosis and management of vesicoureteral reflux in children

Critical evaluation of previously accepted dogma regarding the evaluation and treatment of vesicoureteral reflux (VUR) has raised significant questions regarding all aspects of VUR management. Whereas the standard of care previously consisted of antibiotic prophylaxis for any child with VUR, it is now unclear which children, if any, truly benefit from antibiotic prophylaxis. Operative intervention for VUR constitutes overtreatment in many children, yet there are limited data available to indicate which children benefit from VUR correction through decreased rates of adverse long-term clinical sequelae. Studies with longer follow-up demonstrate decreased efficacy of endoscopic therapy that was previously hoped to approach the success of ureteroneocystostomy. Prospective studies might identify risk factors for pyelonephritis and renal scarring without antibiotic prophylaxis. Careful retrospective reviews of adults with a history of reflux might allow childhood risk factors for adverse sequelae to be characterized. Through analysis of multiple characteristics, better clinical management of VUR on an individualized basis will become the new standard of care.

Vesicoureteral reflux: current concepts and management implications

Long term controlled studies in children with vesicoureteral reflux (VUR) largely conducted in developed societies, challenge the validity of established management principles.The backflow of urine into the upper tracts is not a disease by itself, but part of a clinical spectrum which is heterogeneous and has low risk and high risk categories. Management, medical, endoscopic or surgical have to take into consideration the risk to the child not only from the reflux but also from renal dysplasia and voiding dysfunction which are important risk factors for end stage renal disease (ESRD) and perpetuation of VUR respectively. Social factors, parental choices and access to medical treatment are also important in choosing therapy.

The current evidence based medical management of vesicoureteral reflux: The Sickkids protocol

Vesicoureteral reflux is a common clinical entity and is one of the keystones of the establishment of pediatric urology as a urological subspeciality. There has been continued evolution in the management of vesicoureteral reflux as new insights are gained on its role in renal damage. The optimal treatment algorithm remains controversial. This review aims to highlight the current literature on VUR and its association with urinary tract infections and renal damage. The protocol of management of a child with VUR followed at The Hospital for Sick Children, Toronto is described.