Abstract
Debate persists regarding the merit of vertebroplasty following publication of blinded vertebroplasty trials in 2009, one of which was the Investigational Vertebroplasty Efficacy and Safety Trial (INVEST). This study was performed to determine whether referring physicians at two academic medical centers were aware of the trial results and to assess if this awareness prompted a change in their treatment of osteoporotic fractures. E-mail surveys were distributed to physicians within the Mayo Clinic and Baylor Health Care System (BHCS). Of 1390 surveys sent, 194 (14%) were returned. Results showed that 92 of 158 respondents (58%) reported familiarity with INVEST; 66 of 92 (72%) agreed that INVEST changed their understanding of vertebroplasty efficacy; and 64 of 92 (70%) agreed that INVEST diminished their enthusiasm to refer patients for vertebroplasty. However, 105 of 159 respondents (66%) felt vertebroplasty was an effective procedure in appropriate patients. Mayo physicians were more likely than BHCS physicians to be aware of INVEST (73% vs 67%, P < .0001), respond that INVEST changed their understanding of the appropriate treatment for osteoporotic compression fractures (79% vs 57%, P = 0.026), view vertebroplasty less favorably (45% vs 21%, P = 0.005), and treat osteoporotic compression fractures with medical therapy/pain management alone (73% vs 48%, P = 0.003). INVEST changed referring physicians’ understanding of the role of vertebroplasty and diminished their willingness to refer osteoporotic compression fracture patients; the impact varied by location.
The Investigational Vertebroplasty Safety and Efficacy Trial (INVEST) (1) and a concurrent Australian vertebroplasty trial (2) were published in the New England Journal of Medicine in August 2009 and demonstrated equivalent efficacy for vertebroplasty and a sham intervention for improvement in pain and function in osteoporotic compression fracture patients. Despite extensive criticism (3–8), these studies created controversy regarding the benefit and appropriateness of vertebral augmentation. Historically, the literature has shown positive outcomes associated with thousands of vertebroplasty patients (9, 10). Follow-up vertebroplasty studies have ensued (11, 12), including a study from the Mayo Clinic, which documented a statistically significant decline in referral volumes before and after publication of the August 2009 sham-controlled studies (13). This study was performed to determine whether referring physicians at two academic medical centers, one of which (Mayo Clinic) was the lead site for INVEST, were aware of the INVEST trial results, whether their awareness of these results changed their understanding of the efficacy of vertebroplasty and/or their management decisions for patients suffering from painful osteoporotic fractures, and whether there were differences between the institutions regarding these research questions.
METHODS
Short e-mail surveys were distributed to physicians in a wide range of specialties (Table) that commonly encounter patients with osteoporotic compression fractures within the Mayo Clinic system (Rochester, MN) and the Baylor Health Care System (BHCS, Dallas–Fort Worth, TX). The survey was sent to all physicians with accessible e-mail addresses in these specialty areas, not only to individual physicians who had previously referred patients to interventional neuroradiology for vertebroplasty. Results were collected from September to November 2010 and were analyzed using Survey Monkey. Approval for this research was granted by the institutional review board of Baylor Research Institute.
Table.
Respondents by subspecialty
| Specialty | n | Specialty | n |
|---|---|---|---|
| Cardiology | 4 | Neurosurgery | 5 |
| Endocrinology | 13 | Orthopedic surgery | 6 |
| Family medicine | 40 | Pain management | 6 |
| Gastroenterology | 7 | Physical medicine and rehabilitation | 20 |
| Hematology/oncology | 9 | Pulmonology | 9 |
| Internal medicine | 51 | Rheumatology | 1 |
| Neurology | 14 | Transplant medicine | 5 |
The survey asked participants about their familiarity with the INVEST study, their understanding of the role of vertebroplasty for treatment of osteoporotic compression fractures, if the INVEST results changed their understanding of the treatment for osteoporotic compression fractures or changed their referral patterns for vertebroplasty, and how they were currently treating patients with painful osteoporotic compression fractures. In addition to collecting information on respondents’ specialty, it asked whether they had seen at least one patient during the last 18 months with an osteoporotic vertebral compression fracture.
Statistical analysis of the data was performed with chi-square tests. Physicians were allowed to skip questions. Referring physicians were not queried regarding the Buchbinder et al trial (2) or any of the other vertebral augmentation trials in our survey. No incentives were offered for participation.
RESULTS
Surveys were distributed to 1390 clinicians with a collective response rate of 14% (194 participants). Overall, 92 of 158 respondents (58%) reported being familiar with INVEST (36 respondents did not answer this question), and 53 of these 92 respondents (58%) agreed and 13 (14%) strongly agreed that the results of INVEST had changed their understanding of the efficacy of vertebroplasty (Figure 1); 51 (55%) agreed and 13 (14%) strongly agreed that the study had diminished their enthusiasm to refer patients for vertebroplasty (Figure 2). Cumulatively, 105 respondents (66%) felt that vertebroplasty was an effective procedure in appropriate patients, 52 respondents (33%) felt that vertebroplasty was of limited efficacy, and 2 respondents (1.3%) felt that the potential benefits of vertebroplasty were outweighed by the risks of the procedure (Figure 3).
Figure 1.
Respondents indicating that INVEST changed their understanding of the role of vertebroplasty for treatment of osteoporotic compression fractures. Difference between Mayo and Baylor respondents: χ2 (1, n = 92) = 4.99, P = 0.0255.
Figure 2.
Respondents indicating that INVEST diminished their enthusiasm to refer patients for vertebroplasty. Difference between Mayo and Baylor respondents: χ2 (1, n = 92) = 0.82, P = 0.3662.
Figure 3.
Respondents’ current view of vertebroplasty for treatment of osteoporotic compression fractures. Difference between Mayo and Baylor respondents: χ2 (2, n = 159) = 10.76, P = 0.0046.
There was a statistically significant difference in the responses between clinicians in the two geographic locations, with Mayo physicians being more aware of the INVEST study (63 of 86 [73%] at Mayo vs 29 of 43 [67%] at BHCS; chi-square DF 1, P < 0.001) and responding that INVEST had changed their understanding of the appropriate treatment for osteoporotic compression fractures (Figure 1; 49 of 62 [79%] at Mayo vs 17 of 30 [57%] at BHCS, chi-square DF 1, P = 0.026). There was also a statistically significant difference between clinicians in the two locales in response to descriptions of their current understanding of vertebroplasty for treatment of osteoporotic compression fractures, with Mayo clinicians viewing vertebroplasty less favorably than BHCS physicians (Figure 3; 39 of 87 [45%] at Mayo vs 15 of 72 [21%] at BHCS, chi-square DF 2, P = 0.005). A majority of respondents from both clinician groups indicated that the INVEST results had diminished their willingness to refer patients for vertebroplasty, although the difference between the two respondent groups was not statistically significant for this question (Figure 2; 45 of 62 [73%] at Mayo vs 19 of 30 [63%] at BHCS, chi-square DF 1, P = 0.366). Mayo clinicians were also statistically significantly more likely than BHCS clinicians to treat osteoporotic compression fracture patients with medical therapy and pain management alone, rather than in combination with vertebroplasty (Figure 4; 57 of 78 [73%] at Mayo vs 28 of 58 [48%] at BHCS, chi-square DF 1, P = 0.003).
Figure 4.
Respondents’ approach to treating most of their patients with painful osteoporotic compression fractures. Difference between Mayo and Baylor respondents: χ2 (1, n = 136) = 8.73, P = 0.0031.
DISCUSSION
This survey suggests that INVEST negatively influenced clinicians’ perceptions of and referral patterns for vertebroplasty for treatment of painful osteoporotic compression fractures, similar to the findings reported by Luetmer and Kallmes (13). It also unveiled interesting geographic distinctions, as the survey results varied significantly by location. Though a percentage of physicians at both sites viewed vertebroplasty as an effective procedure in appropriate patients (55% at Mayo vs 79% at BHCS), the referral/utilization rates of vertebral augmentation were notably lower (27% at Mayo vs 52% at BHCS); the reason for this discrepancy is likely multifaceted but was not determined by this survey.
This study sampled a relatively small population of physicians and included inherent bias by limiting the survey to two predefined groups of physicians. The response rate was within the previously published range for e-mail–based surveys, which has been as low as 6% (14). Subgroup analysis by medical subspecialty was not performed due to the relatively small sample size. The Mayo Clinic physicians were likely more aware of the INVEST results since Mayo was the lead site in the original multicenter trial. Peer-to-peer education and interactive discussions were proactively performed at the Baylor University Medical Center campus to educate referring physicians about the INVEST data and to encourage continued patient referrals to interventional neuroradiology. Generalization of these two groups’ responses to the wider medical community may not be entirely representative. Additionally, extrapolation of this information to predict future trends in clinician demand and referral patterns for vertebroplasty is shortsighted without considering all of the subsequent and ongoing clinical trials investigating the efficacy of vertebroplasty.
Further research is needed to address the suggested flaws and confounding factors and to clarify the appropriate treatment of patients with osteoporotic compression fractures. The current ambiguity surrounding vertebroplasty should prompt physicians to enroll as many patients as possible into well-designed trials to help generate data.
Acknowledgments
The authors thank Sunni Barnes, PhD, director of survey research and clinical trials at BHCS.
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