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Prospective Data Collection of a New Procedure by a Specialty Society

The FIBROID Registry

From the Department of Obstetrics and Gynecology, Duke Clinical Research Institute, and Department of Medicine, Duke University Medical Center, Durham, North Carolina; Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California; Society for Interventional Radiology Foundation, Fairfax, Virginia; Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, North Carolina; Department of Public Health Sciences, University of Toronto, Ontario, Canada; Department of Radiology, Georgetown University Medical Center, Washington, DC; and Image Guided Surgery Associates, Philadelphia, Pennsylvania.

	ABSTRACT

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
Objective: To describe registry methods and baseline patient demographics from a national sample of women undergoing uterine artery embolization for uterine leiomyomata.

Methods: Interventional radiology practices were recruited to submit data by a secure Web site on women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline data included patient demographics, prior medical, surgical, and obstetrical history, uterine anatomy, and quality-of-life measures. Subsequent data collected included details of the uterine artery embolization procedure and hospital stay and outcomes at 30 days; patients were also offered the opportunity to participate in longer-term follow-up. Characteristics of white and African-American women were compared using t tests, ², or Wilcoxon rank-sum tests as appropriate.

Results: As of December 31, 2002, 3,319 uterine artery embolization cases had been entered into the registry by 72 sites; number of patients entered by individual sites ranged from 1 to 514. Of these patients, 95.4% consented to participation in the short-term outcomes registry. Forty-eight percent of patients were African American, and 44.4% were white and non-Hispanic. Heavy menstrual bleeding was the single most bothersome symptom in 64.3% of patients. Compared with white non-Hispanic women, African-American women were significantly younger, more likely to be obese, had larger uteri and more numerous leiomyomata, more severe symptoms, and poorer quality-of-life scores before treatment.

Conclusion: It is feasible to collect prospective data on new technologies. The FIBROID Registry prospectively collected data on more than 3,000 women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline patient characteristics of this patient population seem to be similar to those of women undergoing other procedures for leiomyomata.

Level of Evidence: III

Elective uterine artery embolization is a relatively new procedure for the treatment of leiomyomata, first reported in 1995.² From an arterial puncture site, usually the femoral artery, the arterial supply to the uterus is occluded under angiographic guidance by injecting polyvinyl alcohol particles, tris-acryl gelatin microspheres, or gelatin sponges. According to the Society of Interventional Radiology, approximately 25,000–30,000 uterine artery embolization procedures have been performed in the United States (Villarosa L. Women seek choices when leiomyoma tumors strike. New York Times, August 27, 2002. p. F5). In theory, uterine artery embolization is an attractive alternative to other invasive procedures. However, as with most new invasive procedures, the majority of the available literature consists of case studies.

In 1999, the Society of Interventional Radiology Foundation funded and oversaw the development of the Fibroid Registry for Outcomes Data (FIBROID), to collect prospective data on a large number of women undergoing uterine artery embolization. The goals of the registry were to collect data on short- and longer-term safety and effectiveness to help patients and clinicians with decision making regarding therapy for symptomatic leiomyomata, to collect information on subgroups of interest (such as women wishing to become pregnant after embolization), and to test methods for Web-based data collection in a voluntary, specialty-society-based registry, as a model for future evaluation of new procedures. This article describes the registry methods and the preprocedure characteristics of participants in the registry.

	MATERIALS AND METHODS

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
The Registry is a cooperative venture between the Society of Interventional Radiology foundation and the Duke Clinical Research Institute. Before the initial organization of the Registry, an external advisory committee was formed, with representation from epidemiologists, gynecologists, and the Food and Drug Administration Center for Devices and Radiological Health. This committee provided input on appropriate data elements for collection, reporting mechanisms, and study design. Members of the advisory committee continue to provide additional input as needed on an ongoing basis. In addition, a committee of industry representatives provides input on specific data requests of interest to industry.

The Registry is guided by a Steering Committee, which consists of 4 interventional radiologists with extensive experience with uterine artery embolization, representing the Society of Interventional Radiology Foundation, a cardiologist-epidemiologist with extensive experience in design and maintenance of registries, representing the Duke Clinical Research Institute, an epidemiologist with extensive experience in uterine artery embolization research, and a gynecologist-epidemiologist with extensive experience in clinical epidemiology and clinical trials, also representing the Duke Clinical Research Institute. The Steering Committee is responsible for all aspects of Registry organization, including final design of all data-collection forms, adjudication of adverse events, communication with site principal investigators regarding site performance issues, and establishment of publications and other policies. The Steering Committee meets on a quarterly basis, with other meetings by conference call on an as-needed basis.

The Society of Interventional Radiology Foundation staff performs overall site management, including site identification, recruitment, protocol training, and monitoring and serves as the primary liaison with the investigators, Steering Committee, and external organizations. The Society of Interventional Radiology Foundation maintains the registry web site (www.fibroidregistry.org) and arranges committee and investigator meetings and conference calls. All data management, site data management, data analysis, and data reporting are managed at the Duke Clinical Research Institute. Longitudinal follow-up of patients is conducted by the Duke Clinical Research Institute.

Recruitment of sites was done through the Society of Interventional Radiology Foundation and the Society of Interventional Radiology. Sites were classified as "core" or "participating" sites, depending on the amount of data collected.

Final selection of sites was made by the registry Steering Committee, to ensure diversity in geographic location, practice type (academic compared with community), and practice size and experience. Sites were recruited by announcements at meetings, notices in the Society of Interventional Radiology newsletter and Web site, and by personal communication of members of the Steering Committee with colleagues.

Before being given access to the Web-based data collection tools, all sites were required to submit appropriate documentation, including consent forms, institutional review board protocols, formal notice of local institutional review board protocol and consent approval, and number of procedures performed by each investigator to the Duke Clinical Research Institute. An executed site agreement between the Society of Interventional Radiology Foundation and the site was also required before submission of data to the registry.

The Duke Clinical Research Institute and the Society of Interventional Radiology Foundation publish a joint newsletter for sites with answers to frequently-asked questions, reminders about procedures, tips on recruiting, etc. Initial publication was on a monthly basis; recently, publication has been on a quarterly basis, in conjunction with the quarterly reports. Generic data quality issues are discussed in the newsletter.

Although sites did not receive direct compensation for participation in the registry, there are benefits and incentives for participation, including 1) identification as a participant in the registry on the FIBROID Registry Web site and on a Web-based Society of Interventional Radiology physician locator, 2) quarterly reports, which provide site-specific statistics on patient demographics, procedure details, and outcomes, as well as aggregate data for the entire registry, 3) longitudinal follow-up of patients (reports on patient group undergoing uterine artery embolization), and 4) the opportunity to request additional analyses of the data, after approval by the Steering Committee.

All patients provided written informed consent to participate in the Registry. In addition, patients at core sites were also invited to participate in longer-term follow-up, involving follow-up written or telephone questionnaires at 6, 12, and 24 months, and provided separate written consent for participation in this follow-up. The Registry did not determine absolute or relative contraindications for uterine artery embolization, other than those recommended by the Society of Interventional Radiology; the decision to undergo uterine artery embolization was determined by the individual clinicians and patients.

Data elements collected at baseline are shown in . Patient self-reported history and the medical record were used for determination of past history, symptoms, and coexisting diseases such as diabetes and hypertension. Uterine and leiomyoma anatomy was determined either by magnetic resonance imaging (58.3%), transabdominal ultrasonography (39.5%), or transvaginal ultrasound (13.5%), depending on local practice patterns, availability, and patient insurance coverage; although magnetic resonance imaging is more precise than ultrasonography, accuracy is comparable for uteri less than 375 mL, with 4 or fewer myomas, or both.³ Patients also stated their plans for future pregnancy; details on this group will be described in a separate article. If, in the opinion of the investigator, the largest leiomyoma was not the one most likely to be contributing to symptoms, location and morphology for this leiomyoma were also recorded.

At 30 days, follow-up on patients was obtained at each site, preferably by an office visit. Data collected included additional treatments received since the procedure, unanticipated office or emergency room visits, unanticipated hospitalizations or additional procedures, and overall satisfaction with the procedure.

For long-term follow-up, eligible subjects were mailed questionnaires 6, 12, and 24 months after the date of the uterine artery embolization. For the 6-month follow-up, patients were telephoned by a trained interviewer at the identified contact telephone number if questionnaires were not returned within 3 weeks. For longer-term follow-up, nonresponders after 3 weeks are sent a second mailed questionnaire. If there was no response after 4 weeks, patients were telephoned. Using a standard script, patients were reminded about the questionnaire, offered an opportunity to have another questionnaire sent, or the opportunity to answer questions over the telephone.

All baseline, periprocedural, and 30-day data for symptomatic leiomyomata were entered into a secure Web-based data collection form at each site. The Web form was designed to minimize data entry errors by including ranges, prompts, etc. Core sites were expected to submit data within 2 days of the procedure, participating sites within 5 days. For the small percentage of patients who did not consent to participate, only a date, the performance of the procedure, and the patient's refusal to consent were entered.

The database is maintained by staff at the Duke Clinical Research Institute. During active data collection, monthly checks were run for each site; if data entered at the time of procedure indicated that a given patient was eligible for the Registry and had consented to participate, but no additional data are available, an e-mail was sent to the site. However, due to funding limitations, there was no mechanism for formal queries, monitoring, or data verification by either the Society of Interventional Radiology Foundation or Duke Clinical Research Institute.

Results of baseline characteristics are presented as means and medians, with ranges, or proportions. Because there is a large body of evidence that African-American women have different characteristics at the time of surgical management of leiomyomata from white women, we compared baseline characteristics between African-American and white women using t tests, Wilcoxon rank-sum tests, or ² tests, as appropriate.

	RESULTS

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
A total of 101 sites expressed interest in the Registry and were provided materials. Sixteen sites never submitted materials, 11 did not complete all regulatory documents before enrollment was closed, 1 site did not complete site training before enrollment was closed, and 1 site withdrew without submitting any patients. A total of 72 sites were ultimately selected for participation in the registry core sites and participating sites.

The first patient was enrolled December 13, 2000, and at closure of the registry on December 31, 2002, 3,319 patients had been logged into the registry by 72 sites. Although uterine artery embolization continues to be performed at each site, no new patients have been enrolled in the registry. The number of cases per site is shown in Table 4. Five sites enrolled more than 150 patients, 7 sites enrolled between 75 and 150, 11 sites between 75 and 25, and the remainder less than 25. Of these patients, 3,166 (95.4%) consented to participation in the short-term outcomes registry, with complete data on core variables available for 3,005 (94.9%) Overall data quality was excellent. Only 2% or less of patient baseline characteristics were missing, except for symptom and quality-of-life score (14%), and descriptions of uterine anatomy (4–5% missing description of number of leiomyomata and location of largest leiomyoma). Consistently, however, missing data for all variables was more common at participating sites than core sites.

Table 1 illustrates site enrollment by core compared with participating status, academic compared with nonacademic status, and United States compared with international. Core sites were significantly more likely to be academic centers (48% compared with 34%, P < .001) and to have greater experience with uterine artery embolization before enrolling patients in the registry. The mean (± standard deviation [SD]) number of patients for core sites before entry into the registry was 9.4 (± 6.2), compared with 0.99 (± 1.19) for participating sites (P < .001).

Table 2 shows the baseline characteristics of the entire patient group. Almost one half of the patients were African American. Although overall comorbidity was relatively uncommon, overweight and obesity were not, with 12% of subjects with a body mass index (BMI) greater or equal to 35. Mean (± SD) BMI was 27.9 (± 6.8), with a median BMI of 26.5. Heavy menstrual bleeding (84.5%), pain (62.1%), and bulk-related symptoms (83.9%) were all common, but heavy menstrual bleeding was the single most bothersome symptom in 64.3% of patients (Table 3). Less than one half of patients had either medical therapy within 3 months of the procedure (45.3%) or a previous procedure (34.7%). Table 4 illustrates the baseline uterine anatomy characteristics. Mean (± SD) uterine volume was 677.7 (± 520.4) mL; 43.4% of patients had 1 or 2 leiomyomata, while 32.6% had 5 or more.

Table 5 shows the comparison of baseline characteristics between African-American and white women. African-American women enrolled in the Registry are younger, more likely to be obese, and have larger uteri and more numerous leiomyomata than white women. Bulk-related symptoms such as bloating or urinary frequency were less likely to be the predominant symptom in African-American women, despite their larger uteri. Both symptom scores and quality-of-life results suggest that, on average, symptoms are more severe in African-American women.

	DISCUSSION

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
Despite the public health effect of leiomyomata, there is a remarkable lack of evidence on the effectiveness, especially the long-term effectiveness, of any medical or surgical therapy for symptoms related to leiomyomata: a recent systematic review of the literature conducted as part of the Evidence-based Practice Center program of the Agency for Healthcare Research and Quality concluded that the available evidence on management of uterine leiomyomata was of poor quality.^6,8 The review found an almost total absence in the published literature of randomized trials comparing any medical or surgical treatment to another. The majority of studies of outcomes of single treatments were limited by retrospective data collection, small sample size, variable follow-up, lack of characterization of symptoms and pretreatment uterine anatomy, and lack of standardized and validated outcome measures. Even the best studies of hysterectomy, which reported both short- and long-term outcomes, and used standardized, validated instruments for measuring physical and psychological outcomes^5,9,10, are limited by inclusion of women undergoing hysterectomy for a variety of indications. The number of women undergoing hysterectomy for leiomyomata were relatively small (31,⁹ 145,¹⁰ and 625 ⁵), and results were not reported separately by indication. Although the authors of all studies stated that results did not differ among indications, the potential impact of factors such as preoperative size of the uterus, number and location of leiomyomata, and specific type of symptoms on outcomes is not reported.

The FIBROID Registry was able to enroll more than 3,000 women undergoing a procedure for symptomatic uterine leiomyomata and thus represents the largest available cohort of women undergoing a single therapy for this condition. A subsequent article will report on the short-term outcome, and future articles will report on longer-term follow-up. Given that new procedures can be introduced without the need for approval from the Federal Drug Administration or other regulatory agencies, voluntary registries organized by specialty societies early after the introduction of a new procedure may be 1 of the few ways to collect prospective data on outcomes in ways that avoid the limitations of single-center studies, industry-sponsored trials, or administratively collected data. For example, registries of laparoscopic cholecystectomy organized by state or regional medical societies were instrumental in providing data about the relationship between safety and physician experience.¹¹ One of the particular strengths of this Registry is the availability of data on patient characteristics, such as obesity and uterine anatomy, that may affect the difficulty of the procedure, and therefore allow more meaningful risk adjustment than is offered by administrative data.¹² The experience of the Society of Interventional Radiology with the FIBROID Registry can be a model for other specialty societies as new procedures are introduced into practice.

Another key aspect of this registry is the use of a disease-specific validated questionnaire to measure symptom status and health-related quality of life.¹³ Previous studies have used generic quality-of-life instruments, which may not be as sensitive to small changes in quality of life. Because most of the clinical impact of leiomyomata is based on subjective symptoms, it was important to try to provide the most reliable and repeatable measure of that status for evaluation of patient outcome over time.

Although missing data elements became more common with time, the proportion of data elements that were complete remained above 90% throughout, a proportion that is as good or better than other voluntary registries.¹⁴ The baseline data in the Registry suggests that women undergoing uterine artery embolization are similar in many measurable respects to women undergoing surgical management of leiomyomata, particularly hysterectomy,^5–7,10,11 and are also similar to those reported in other large studies of women undergoing uterine artery embolization, such as the Ontario Uterine Fibroid Embolization Trial.¹⁵ In particular, differences between African-American and white women in age, body mass index, uterine anatomy, and symptom severity are similar to reported differences in large studies of women undergoing a variety of invasive procedures for leiomyomata, including hysterectomy³ and myomectomy⁵ as well as uterine artery embolization.

In summary, voluntary, prospective collection of data in patients undergoing a new procedure in a wide range of clinical settings is feasible. From the data collected in the FIBROID Registry, reported characteristics of women undergoing uterine artery embolization seem similar to women undergoing other procedures for management of leiomyomata. Ongoing data collection and analysis should provide additional insight into both short- and long-term outcomes of this procedure, as well as provide important information to help design future studies comparing uterine artery embolization with other management options.

	Appendix

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
FIBROID Registry core site principal investigators are listed below: Anne Roberts, MD, University of California San Diego Medical Center, La Jolla, CA; Jeffrey Dieden, MD, Kaiser Medical Center, Oakland, CA; Mahmood Razavi, MD, Stanford University Hospital, Palo Alto, CA; Michael Hines, MD, Kaiser Permanente Hospital, Vallejo, CA; James Spies, MD, Georgetown University Hospital, Washington, DC; James Benenati, MD, Miami Cardiac and Vascular Institute, Miami, FL; Gerald Niedzwiecki, MD, Mease Countryside Hospital, Safety Harbor, FL; John Lipman, MD, Radiology Associates of Atlanta, Atlanta, GA; Robert Vogelzang, MD, Northwestern Memorial Hospital, Chicago, IL; Steven Smith, MD, LaGrange Memorial Hospital, LaGrange, IL; Karen Ehman, MD, Methodist Hospital, Indianapolis, IN; Moises Yoselevitz, MD, Ochsner Clinic Foundation, New Orleans, LA; David Brophy, MD, Mount Auburn Hospital, Cambridge, MA; Rajinder Sharma, MD, Henry Ford Hospital, Detroit, MI; William Romano, MD, William Beaumont Hospital, Royal Oak, MI; David Hovesepian, MD, Mallinckrodt Institute of Radiology, St. Louis, MO; Mark Garcia, MD, Christiana Care Health Services, Newark, NJ; Gary Siskin, MD, Albany Medical Center, Albany, NY; Robert Min, MD, Cornell Vascular-New York Presbyterian Hospital New York, NY; James Newman, MD, Cleveland Clinic Foundation, Cleveland, OH; Robert Worthington-Kirsch, MD, Delaware Valley Imaging, Philadelphia PA; Joseph Bonn, MD, Thomas Jefferson University Hospital, Philadelphia, PA; Richard Schlansky-Goldberg, MD, Hospital of the University of Pennsylvania, Philadelphia, PA; Keith Sterling, MD; INOVA Alexandria Hospital, Alexandria, VA.

	Footnotes

 
See related article on page 52.

* For a list of the FIBROID Registry core site principal investigators, see the Appendix.

No statement in this article should be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.

Address reprint requests to: Evan R. Myers, MD, MPH, DUMC 3279, 244 Baker House, Duke University Medical Center, Durham, NC, 27710; e-mail: myers008{at}mc.duke.edu.

Financial Disclosure Establishment of the registry and data collection were funded by the Society for Interventional Radiology Foundation through unrestricted grants from Biosphere Medical, Boston Scientific Corporation, COOK, Inc, and Cordis Endovascular; additional funding for analysis was provided by the Agency for Healthcare Research and Quality and the Food and Drug Administration Office of Women's Health.

doi:10.1097/01.AOG.0000165827.66541.dd

	REFERENCES

TOP ABSTRACT MATERIALS AND METHODS RESULTS DISCUSSION Appendix REFERENCES

 
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3. Dueholm M, Lundorf E, Hansen ES, Ledertoug S, Olesen F. Accuracy of magnetic resonance imaging and transvaginal ultrasonography in the diagnosis, mapping, and measurement of uterine myomas. Am J Obstet Gynecol 2002;186:409–15.[Medline]

4. Hovsepian DM, Siskin GP, Bonn J, Cardella JF, Clark TW, Lampmann LE, et al. Quality improvement guidelines for uterine artery embolization for symptomatic uterine leiomyomata. J Vasc Interv Radiol 2004;15:535–41.[Medline]

5. Kjerulff KH, Rhodes JC, Langenberg PW, Harvey LA. Patient satisfaction with results of hysterectomy. Am J Obstet Gynecol 2000;183:1440–7.[Medline]

6. Matchar DB, Myers ER, Barber MW, Couchman GM, Datta S, Gray RN, et al. Management of uterine fibroids. Evid Rep Technol Assess (Summ) 2001;34:1–6.

7. Roth TM, Gustilo-Ashby T, Barber MD, Myers ER. Effects of race and clinical factors on short-term outcomes of abdominal myomectomy. Obstet Gynecol 2003;101:881–4.[Abstract/Free Full Text]

8. Myers ER, Barber MD, Gustilo-Ashby T, Couchman G, Matchar DB, McCrory DC. Management of uterine leiomyomata: what do we really know? Obstet Gynecol 2002;100:8–17.[Abstract/Free Full Text]

9. Weber AM, Walters MD, Schover LR, Church JM, Piedmonte MR. Functional outcomes and satisfaction after abdominal hysterectomy. Am J Obstet Gynecol 1999;181:530–5.[Medline]

10. Carlson KJ, Miller BA, Fowler FJ Jr. The Maine Women's Health Study: I. Outcomes of hysterectomy. Obstet Gynecol 1994;83:556–65.[Medline]

11. Orlando R 3rd, Russell JC, Lynch J, Mattie A. Laparoscopic cholecystectomy: a statewide experience. The Connecticut Laparoscopic Cholecystectomy Registry. Arch Surg 1993;128:494–8.[Abstract]

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13. Spies JB, Coyne K, Guaou Guaou N, Boyle D, Skyrnarz-Murphy K, Gonzalves SM. The UFS-QOL, a new disease-specific symptom and health-related quality of life questionnaire for leiomyomata. Obstet Gynecol 2002;99:290–300.[Abstract/Free Full Text]

14. Jacobs JP, Mavroudis C, Jacobs ML, Lacour-Gayet FG, Tchervenkov CI, William Gaynor J, et al. Lessons learned from the second harvest (1998–2001) of the Society of Thoracic Surgeons (STS) Congenital Heart Surgery database. Eur J Cardiothorac Surg 2004;26:18–37.[Abstract/Free Full Text]

15. Pron G, Cohen M, Soucie J, Garvin G, Vanderburgh L, Bell S. The Ontario Uterine Fibroid Embolization Trial. Part 1. Baseline patient characteristics, fibroid burden, and impact on life. Fertil Steril 2003;79:112–9.[Medline]

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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Myers, E. R. Search for Related Content PubMed PubMed Citation Articles by Myers, E. R. Related Collections Immunology