Correspondence: Dr. Andreas Laupacis, St. Michael’s Hospital, 30 Bond Street, Toronto, ON, Canada M5B 1W8; laupacisa@smh.ca
It would be difficult to be a Canadian and be unaware of the controversy regarding
endovascular treatment for multiple sclerosis (MS). Dr. Paolo Zamboni,
an Italian physician, has hypothesized that MS is caused by a newly
discovered abnormality of venous drainage from the brain that he has
called chronic cerebrospinal venous insufficiency (CCSVI), and that
endovascular treatment of CCSVI can markedly improve the symptoms of MS.1,2
The endovascular treatment has been given the rather sensational name
“liberation procedure,” invoking the notion of “setting free.” The
overwhelming majority of MS researchers dismiss Dr. Zamboni’s findings
because they fly in the face of what is known about the etiology of MS,
and because of questions about the scientific quality of Dr. Zamboni’s
work. His studies of the association between CCSVI and MS have not been
consistently replicated, and his trial addressing the effectiveness of
endovascular treatment was not randomized. As well, although Zamboni
found no serious complications in 65 MS patients undergoing angioplasty
of the jugular veins, no large-scale study of complications has been
reported. These are important and valid criticisms.
The public profile of CCSVI in Canada was raised in the fall of 2009 by a relatively uncritical article in The Globe and Mail (Toronto), and an even more uncritical broadcast on the CTV public affairs program W5.3,45 They demand that endovascular treatment be made available in Canada or,
at the very least, that a randomized trial of the procedure be started
immediately.
Both portrayed Dr. Zamboni as a pioneer whose theories were discounted
by conventional medicine and focused relatively little on the criticisms
of his studies. Many Canadians with MS, eager for an effective
treatment for this miserable disease, have been convinced by Dr.
Zamboni’s research, and by the testimonials of patients who have
travelled to other countries to receive the procedure. They accuse many
in the MS scientific community of being narrow minded, obsessed with
irrelevant scientific niceties, and/or of being in the clutches of the
pharmaceutical industry.
Into this perfect storm have marched the Canadian Institutes of Health Research (CIHR) and the Multiple Sclerosis Society of Canada. In
September of this year they released a summary of the deliberations of a
“Joint Invitational Meeting” of 15 clinical and scientific experts, 5
employees of the CIHR, 3 employees of the MS Society, and one
unidentified person with MS. The panel examined the scientific
literature relating CCSVI and MS, and decided that the evidence linking
CCSVI and MS was so unconvincing that it would be inappropriate at this
time to perform a clinical trial examining the benefits and risks of
endovascular treatment as a therapy for MS.6
Too often, health care interventions are introduced on the basis of poor scientific evidence. Therefore, what the CIHR and MS Society have
attempted to do seems admirable to those of us who are proponents of
evidence-based health care and evidence-informed policy-making. A review
and summary of all research that is relevant to important health policy
decisions by unbiased experts can be used by politicians and
policy-makers to make policy decisions, in this case whether to fund
endovascular treatment for CCSVI, either as part of a randomized trial
or through the publicly funded health care system. However, we suggest
that there are important lessons to be learned from this panel’s
experience that should be considered when constituting future panels
that address other issues that are at the intersection of science,
advocacy and policy-making.
Concerns have been raised about the membership of the expert panel.7 No proponents of the liberation procedure participated in the
Invitational Meeting, which seems odd. Most scientific experts have some
degree of conflict of interest, and these are usually dealt with by
publicly declaring them, not by excluding a particular point of view
from a panel. Conversely, the potential conflicts of interest of the
individuals who were on the panel were not described in the report, thus
allowing some to accuse the CIHR of attempting to hide their potential
biases.8
The panel recommended that no clinical trials of endovascular treatment for CSSVI should be conducted until the association between MS
and CCSVI has been firmly established. The rationale for this
recommendation is sensible: one should not expose MS patients to the
risks of endovascular therapy—which, although rare, can be fatal9,10—
if there is no rational scientific reason to think that CCSVI causes
MS. However, the panel spent little time either justifying their
controversial recommendation or discussing potentially opposing points
of view. We believe that both the panel’s approach to the problem and
its membership were too narrow to completely fulfill its mandate.
It appears to us that the panel addressed three questions. The first question was whether current evidence establishes that patients with MS
have a higher frequency of CCSVI than patients without MS. The second
was whether current evidence establishes that the benefits of
endovascular treatment in patients with MS outweigh the risks. The third
was whether a publicly funded randomized trial of endovascular therapy
for MS should be initiated now.
The first two questions are largely ones of science, and are best addressed by highly qualified experts who represent the diversity of
views in the scientific community. However, we believe that although the
third question must be informed by science, it should be addressed
using a broader perspective. A clinical trial of endovascular treatment
funded by the CIHR or provincial governments would consume public
resources, which are clearly limited. Given the controversy, and given
the way this issue has galvanized the public, the decision about whether
to conduct a clinical trial should be informed by the public. We
believe that members of the public, beyond 3 employees of the MS Society
and one anonymous person with MS, should have been included on the
Joint Invitational Meeting panel. By “members of the public,” we do not
mean only patients with multiple sclerosis or advocates for MS
patients, but also thoughtful citizens without MS who can consider all
points of view, deliberate about them, and contribute to informed
recommendations.
If half a dozen or so such individuals had participated in the deliberations, they might have asked questions about why proponents of
the liberation procedure were not members of the panel, and they would
have contributed greatly to the discussion about the appropriateness of a
clinical trial in the face of poor scientific evidence supporting the
CCSVI hypothesis and uncertainty about the risks of endovascular therapy
(which appear to vary depending upon whether or not a stent is
inserted). They would likely have encouraged the panel to more fully
articulate the reasons why a clinical trial should not (or possibly
should) be conducted now, and might have had different views about how
to balance information about the risks and potential benefits of
angioplasty. A number of Canadians are now using their own resources to
travel to other countries to undergo endovascular treatment, performed
by surgical teams whose quality standards are not always clear. Would
these patients be better off, and policy-makers and the public better
informed, if a randomized trial were conducted now? If patients are
fully informed about current doubts regarding the association of CCSVI
and MS, as well as the limitations of Zamboni’s non-randomized trial of
endovascular treatment, and the potential side-effects of endovascular
treatment, should they be given the opportunity of participating in a
trial now? Of course, surgeons and interventional radiologists should
not participate in the trial if they feel that the current evidence
suggests they are likely to do more harm than good to their patients.
However, we know of reputable Canadian vascular surgeons who would
operate on MS patients in the context of a randomized trial.
Even had greater public membership on the panel not changed the recommendations made in the report at all, or had the committee not been
able to come to a consensus, the very fact that members of the public
were on the committee would likely have increased the legitimacy of the
report in the eyes of the public (although not in everyone’s).
The public pays for research funded by the CIHR and the MS Society of Canada, are affected by the findings, and are more likely to be
supportive of research in general if they feel that researchers are more
in touch with the community. The CIHR has itself, in reference to its
Stem Cell Oversight Committee, stated “Technical experts will provide
the Committee access to the latest scientific and ethical information,
and representatives from the general public will represent the views and
values of Canadians potentially affected by the new technologies.”11
We agree with this statement and suggest that, in the future, members
of the public should be more actively involved in scientifically based,
but patient-relevant and emotionally charged, issues considered by the
CIHR, by other Canadian research organizations and by the provincial,
territorial and federal governments.
References
- Zamboni P, Galeotti R, Menegatti E, Malagoni AM, Tacconi G, Dall'Ara S, et al. Chronic cerebrospinal venous insufficiency in
patients with multiple sclerosis. J Neurol Neurosurg Psychiatry 2009;80(4):392–399. [CrossRef] [PubMed] [Full Text]
- Zamboni P, Galeotti R, Menegatti E, Malagoni AM, Gianesini S, Bartolomei I, et al. A prospective open-label study of endovascular
treatment of chronic cerebrospinal venous insufficiency. J Vasc Surg 2009;51(4):1348–1358. [CrossRef] [PubMed] Erratum in: J Vasc Surg 2010;51(4):1079
- Picard A, Favaro A. Researcher’s labour of love leads to MS breakthrough. The Globe and Mail (Toronto) 2010 Sept 20 (accessed 2010 Sept 26). [Full Text]
- CTV News. The Liberation Treatment: A whole new approach to MS. W5 (accessed 2010 Sept 26). [Full Text]
- Smith J, Ogilvie M. MS doctors attacked for their skepticism. The Toronto Star 2010 Sept 24 (accessed 2010 Sept 26). [Full Text]
- CIHR and MS Society of Canada. Joint Invitational Meeting on Multiple Sclerosis Research - Summary Report (accessed 2010 Sept 26). [Full Text]
- Canada - What you need to know (accessed 2010 Nov 2). [Full Text]
- Kingston A. Liberation therapy for MS patients still locked away. Maclean's 2010 Sept 23 (accessed 2010 Nov 2). [Full Text]
- Rudick RA. Multiple sclerosis: Is multiple sclerosis caused by venous insufficiency? Nat Rev Neurol 2010;6(9):472–474. [CrossRef] [PubMed] [Full Text]
- Ont. Man dies after MS vein opening. CBC News 2010 Nov 18 (accessed 2010 Nov 19). [Full Text]
- Venuta R, Graham ID. Involving citizens and patients in health research. J Ambul Care ManageCrossRef] [PubMed] 2010;33(3):215–222. [
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