Abstract
PURPOSE:
To characterize common clinical indications for urodynamic, a bladder function test, in adults with spina bifida.
METHODS:
A retrospective chart review was performed for 215 patients seen in an adult multidisciplinary spina bifida clinic who were registered with the National Spina Bifida Patient Registry from October 2011 to October 2018. Descriptive statistics were used for statistical comparisons.
RESULTS:
A total of 52 of 215 patients developed a clinical indication for urodynamics. Of these, 71 (33%) patients (8 of whom underwent testing twice) had urodynamics performed, resulting in a total of 79 urodynamic study encounters that were analyzed. Thirty-four (43%) urodynamic testing cases were performed due to a symptomatic change in lower urinary tract function; 14 (18%) were due to declining renal function or concern for upper tract deterioration based on imaging. The data obtained from urodynamic investigation led to new recommendations for urinary tract management in 59 (75%) of the urodynamic studies performed. A total of 32 of the 90 (35%) recommendations made were surgical interventions and 30 (33%) were for a change in medical management. Interestingly, 8 of the 18 (44%) routine or baseline urodynamic tests performed led to new recommendations in urinary tract management.
CONCLUSION:
A total of 24%of patients in the multidisciplinary spina bifida clinic developed an indication for urodynamic testing over a 7-year period which resulted in new recommendations for urinary tract management in most. As more patients with spina bifida enter adulthood, the indications for urodynamic evaluation may become more defined, since the results often lead to alterations in bladder management.
Introduction
As medical and surgical care has improved, more than 90%of patients born with spina bifida survive into adulthood compared to only a 10–12%survival rate prior to 1960 [1, 2]. Patients with spina bifida have a greater than 90%incidence of urinary tract dysfunction and 30–40%incidence of renal damage was found even within the pediatric population [3, 4]. As more patients with spina bifida enter adulthood, they present more frequently to adult urology clinics, as lifelong urological care is necessary for this population [4]. While urologic monitoring most commonly consists of yearly history and physical examinations along with imaging, occasionally more advanced testing (such as urodynamic studies) may be indicated [5]. Recently, a systematic review addressed the role of urodynamic parameters in predicting upper tract deterioration. It reported that patients with spina bifida have a higher risk of upper tract deterioration compared to patients with slowly progressive non-traumatic neurologic disorders [6].
Routine use of urodynamics in the pediatric spina bifida population is done for early detection of abnormal bladder parameters that may lead to a deterioration of renal function and/or the ability to store urine. Recently, the Spina Bifida Association developed guidelines for the timing of urodynamics in the pediatric population that reinforce this proactive approach for patients less than 12 years old. In contrast, most urodynamic testing in adults is done in a reactive or “as-needed” basis when acute urologic issues arise [7]. At this time, it is not known if more proactive or routine testing should be implemented in the adult population. Existing data supports serial urodynamic testing, even when the initial newborn results demonstrate normal bladder function [5, 9]. This is because although spina bifida is not considered a progressive neurological disorder, lower urinary tract function in these patients may change over time and lead to deterioration of the upper urinary tract structure and function.
The Spina Bifida Association recently released the 4th edition of the Guidelines For The Care Of People With Spina Bifida [10, 11]. The primary urologic goals focus on maintaining normal renal function, achieving socially acceptable urinary continence, and maximizing urologic independence. The guidelines recommend yearly routine renal ultrasounds throughout the patient’s life, as well as additional renal ultrasonography in the setting of recurrent urinary tract infections (UTIs) or if urodynamic testing suggests bladder problems. According to the guidelines, urodynamic testing should also be done yearly until age 3 and then again at the age when a urinary continence program is implemented if complications arise. From age 6 through 12, the guidelines recommend that urodynamics be repeated as needed in the setting of upper tract changes, recurrent UTIs, or changes in continence status. From age 13 and up, the guidelines do not address when to use urodynamic testing. The primary aim of this report is to review the reactive utilization of urodynamic testing in adults with spina bifida at a major referral institution to characterize the indications for, as well as evaluate the impact of urodynamic studies on treatment decisions.
Methods and materials
Institutional Review Board approval was obtained, and a retrospective study was conducted of consecutive patients registered to be seen in the adult multidisciplinary spina bifida clinic at the University of Alabama at Birmingham between October 2011 through October 2018. All of these patients were registered in the National Spina Bifida Patient Registry. Annual surveillance of patients in this clinic included a physical examination, imaging with a renal ultrasound, and abdominal x-ray. Additionally, those patients with previous urinary diversion or reconstruction underwent annual serum chemistries and periodic cystoscopy. The following information was collected: 1) prior and current bladder management including bladder management method at the time of the urodynamic study; 2) use of medication to modulate bladder function; 3) indications for urodynamic testing; 4) physician recommendation for change in bladder management as a result of the urodynamic testing; 5) type of physician-recommended change in bladder management. Most urodynamic testing was performed based on the rationale for using urodynamic testing in the pediatric population as recommended by the Spina Bifida Association. All recommendations for urodynamic testing were made by a urologist, most of them from the principal institution. Outside institution recommendations for urodynamic testing were reviewed by the spina bifida clinic urologists to ensure that the indications were appropriate. Demographic information such as age at time of urodynamic testing, sex, and level of myelomeningocele was also collected. Descriptive statistics were used for data reporting.
Results
Of 215 patients, 76 underwent urodynamic studies during the 7-year time period. Five were excluded due to missing or incomplete treatment plans after the urodynamics were performed. A total of 52 (24%) patients developed an indication for and subsequently underwent urodynamic testing, while 23 patients were lost to follow up (i.e. had not been seen in 4 or more years or had never seen a urologist). Only 28%lived within 50 miles of the clinic. Data from a total of 71 patients were included in this study. Of these, 8 underwent urodynamic testing twice, resulting in a total of 79 urodynamic encounters that were analyzed for this study. 55%of the patients who underwent urodynamic testing during the study time frame were female. The majority (63%) were between the age of 19–29 at the time of urodynamics, while just 6%were 50 or older. While 70%of patients had a spina bifida abnormality at either the thoracic or lumbar spinal lesion, the remaining 30%had thoracolumbar, lumbosacral, or sacral level abnormalities (Table 1).
Demographics
Demographics
*Evaluation by any urologist for a genitourinary cause since transition to adult urologic care. +Represents 79 urodynamic encounters with 8 of the 71 patients undergoing UDS twice during the 7-year time period. ABBREVIATIONS: Lower urinary tract (LUT).
At baseline and at the time of urodynamic testing, this cohort used a variety of strategies for bladder management with 57%utilizing clean intermittent catheterization (CIC). While 18%of subjects were volitionally voiding with or without voiding symptoms, 18%had no bladder management (i.e. had total incontinence into a diaper or used a condom catheter), and 8%utilized continuous bladder drainage with a Foley or suprapubic catheter. Although the majority of patients had some degree of voiding dysfunction, 65%were not on any type of medication to mitigate their symptoms at the time of urodynamic testing (Table 1).
Indications for urodynamic testing in this patient population included symptomatic change in lower urinary tract function (43%), recurrent symptomatic or febrile urinary tract infections (27%), and decline in renal function as evidenced by abnormal renal labs or new onset and/or worsening hydronephrosis (18%). Approximately 23%of urodynamic studies were performed for routine/baseline purposes (e.g. routine check-up, post-intervention follow-up, no prior history of urodynamic studies, socioeconomic/geographic obstacles to clinic access). After undergoing urodynamics, providers recommended a change in patient care management in 59 of the 79 encounters. Providers recommended a total of 90 changes in genitourinary management. In total, 35%of the recommendations made were surgical interventions and 33%were medical management changes.
Other recommendations are noted in Table 2. Urodynamic testing resulted in two or more of these recommendations 64%of the time. Interestingly, 8 of 18 routine or baseline urodynamic testing led to a change in patient care management.
Urodynamic Utilization
+Represents 79 urodynamic encounters with 8 of the 71 patients undergoing UDS twice during the 7-year time period. @Changes in lower urinary tract (LUT) function includes worsening incontinence, increase in pericatheter leak, increase frequency of CIC. #Other includes elevated post void residuals, recurrent bladder or renal stones and pre-transplant evaluation. &Represents total number of changes in recommendations; 23 patients had 2 changes and 4 had 3 changes. *These interventions included: onabotulinumtoxin A bladder injections, placement of a suprapubic catheter, augmentation cystoplasty, continent catheterizable channel creation, ileal conduit creation, pubovaginal sling placement, bladder neck closure, deflux of ureteral orifice, and ureteral stent placement. ABBREVIATIONS: Clean intermittent catheterization (CIC); Lower urinary tract (LUT); Urinary tract infection (UTI).
A total of 24%of patients managed by the adult spina bifida clinic developed an indication for urodynamic evaluation over a 7-year period. The most common indications for testing were a symptomatic change in lower urinary tract function, symptomatic recurrent/febrile UTIs, and signs of upper tract deterioration. The data obtained from this urodynamic investigation led to new recommendations for urinary tract management after 75%of the tests, and 35%of these recommendations were for surgical interventions. These interventions ranged from intradetrusor injection of onabotulinumtoxin A or placement of a suprapubic catheter, to more invasive procedures such as augmentation cystoplasty with or without a catheterizable channel, or pubovaginal sling placement.
The adult multidisciplinary spina bifida clinic at the University of Alabama at Birmingham (UAB) was established in 2010 through coordination and collaboration with the existing pediatric spina bifida team at Children’s of Alabama and the adult spinal cord injury clinic team at UAB. The development and design of this clinic have been previously published and the patients treated were all registered with the National Spina Bifida Patient Registry. These patients represented a heterogenous cohort with regard to prior urologic and medical care with just 39.4%having received prior urologic care at the affiliated children’s hospital [12]. Of the 215 patients who underwent UDS testing, 11%had either been lost to urologic follow-up for 4 or more years, or had never been seen by a urologist. Many of the patients seen in this clinic were referred by a PCP, ED, or urgent care facility after an acute urological issue. Others found the clinic via an internet search and/or the UAB hospital website. The majority of the current patients lived in rural communities with virtually no public transportation options. In fact, only 28%of the patients in this study lived within 50 miles of the clinic while 27%lived over 100 miles away (Table 1).
Health care providers caring for spina bifida patients should maintain heightened surveillance of possible bladder dysfunction since a significant number of these patients may need urodynamic testing as adults, even if they have transitioned from pediatric urology oversight. One study found that of the adult patients with spina bifida presenting to urology clinic for the first time, 52%reported urinary incontinence and 34%reported recurrent urinary tract infections [13]. Patients presenting with these symptoms may benefit from early use of urodynamic testing to aid in management and improvement in quality of life. In the current study population, many adult spina bifida patients are reluctant to undergo the recommended urodynamic studies because of negative childhood experiences with this invasive intervention. Further investigation of the patients seen in this clinic who did not undergo urodynamic studies is needed to determine the reasons for noncompliance. These authors plan to begin to prospectively collect more data on this issue. Indeed, practitioners who treat adults with spina bifida have observed low levels of compliance with routine follow-up care [7, 13]. This was demonstrated by the finding that just 35%of the patients in this study used oral medications to modulate lower urinary tract function even though the majority had active prescriptions for these medications.
While the current Spina Bifida Association guidelines do not advocate for routine urodynamic testing in adult patients with spina bifida, the current study findings suggest that a large number (44%) of patients who underwent routine or baseline urodynamic testing had a change in management of their neurogenic bladder management. This may point to a need for continued routine urodynamic surveillance in those with spina bifida even after they reach adulthood. Though it does not specifically address spina bifida, the European Association of Urology guidelines on neuro-urology recommend baseline urodynamics and that high-risk patients undergo urodynamic testing at regular intervals [14]. Additionally, Veenboer et al performed a systematic review of 18 studies published between 1994 and 2011 on the long-term outcomes of adult patients with spina bifida. Although the quality of evidence in those articles was not strong enough to make robust recommendations, it was advised that urodynamics be performed routinely every 2-3 years [15].
This study has limitations due to its retrospec-tive nature, case-only design, and inherent selection bias. It does not consider patients who did not undergo recommended urodynamic testing or patients who did not require urodynamic testing. Additionally, a lack of consistent pediatric urological records and prior/pediatric urodynamic studies prevented more robust analyses. Finally, inconsistent post-intervention urodynamic testing prevented comparison to the pre-intervention findings. Thus, the utility of testing could not be confirmed. Strengths of this study include a relatively large unique patient population and presence of a well-established multidisciplinary spina bifida clinic that has been in existence for over 10 years. The authors are currently setting up a more robust internal database to prospectively collect data that will better address and streamline future research endeavors.
Conclusion
This study adds to the growing interest in the urologic care of the adult spina bifida patient and is the first to utilize patients in the National Spina Bifida Patient Registry to describe adult urodynamic utilization [16]. The findings suggest that some adult spina bifida patients may benefit from a more proactive approach to their care, specifically the implementation of routine urodynamic testing.
Footnotes
Acknowledgments
The authors wish to thank Ms. Betsy D. Hopson MSHA, Comprehensive Spina Bifida Program Coordinator, and Dr. L. Keith Lloyd for their contributions to this study.
Conflict of interest
The authors have no competing interests to declare.