Herald Column: In Search of Evidence-Based Policy

My latest Calgary Herald column looks at some recently published studies and how they contrast with government policy:

 

...In recent days, we’ve seen new evidence emerge further confirming our lamentable trajectory away from evidence-based policy.
The question of Vancouver’s safe injection site, better known as Insite, is one example. A court ruling next month will help decide whether Insite continues to operate under an exemption to federal drug laws – an exemption the Conservatives seem intent on ending.
The evidence tells us quite overwhelmingly, though, that Insite’s approach works. The latest study, published in the The Lancet, shows the fatal overdose rate near the Insite facility fell by 35 per cent over the first 27 months of its operation, whereas the rate dropped by just nine per cent over the rest of the city.
Even more remarkably, though, for women and aboriginals, the rate drop near Insite was 50 per cent, whereas the rate for those two groups actually doubled in the rest of Vancouver.
The case against Insite seems primarily ideological, but it’s not always ideology that leads us astray. In fact, it can often be a well-meaning desire to “protect” people. Not that there’s anything wrong with keeping people safe, but we need evidence to determine what those dangers are. Often the precautionary principle is taken too far.
That appears to be the case with Bisphenol-A (BPA). Canada took the lead in banning the chemical from baby bottles, and recently BPA was added to Canada’s official list of toxic substances.
Last year, however, an international panel of experts convened by the World Health Organization concluded that the evidence for BPA's alleged health risks is weak, and that a ban is premature. A study published this month in the journal Critical Reviews in Toxicology concurs.
It found that current tolerable daily intake levels for BPA are sufficient and that most people come nowhere near those limits. The study concludes that “available evidence indicates that BPA exposure represents no noteworthy risk to the health of the human population, including newborns and babies”.
So did Canada overreact? So it would seem. And yet, no politicians have called attention to this.
Another area where a well-meaning effort to help people appears at odds with the scientific evidence is the so-called “Liberation Treatment” for multiple sclerosis (MS) based on Italian researcher Paolo Zamboni’s theory that the disease is caused by vein blockages, dubbed CCSVI.
Many Canadian politicians have taken an unusually active interest in this. Alberta committed $1-million to a study of the procedure, and other provinces promised funding for clinical trials – despite the Canadian Institutes for Health Research (CIHR) warning against doing so. The federal Liberals even criticized the Conservatives for following the CIHR’s advice.
However, many subsequent studies have found no correlation between these blockages and MS. So far no one has replicated Zamboni’s findings.
A large study this month out of the University of Buffalo found CCSVI in 56 per cent of MS patients, and 42 per cent among those with other neurological condition. It was also present in 23 per cent of healthy patients. The authors suggest that MS might be causing CCSVI, but conclude the reverse is unlikely.
More research is needed, but so far the scientific evidence is not matching the enthusiasm of many policy makers. While the door should not yet be closed on this theory, we should consider the risks of devoting great amounts of resources into a theory that might not pan out.
Many hopes were raised by Zamboni’s theory, but wanting it to be true does not make it so. As disappointing as it may be, we need to heed the evidence.
As we’ve seen, though, when the evidence clashes with our hopes, our fears, or our long held beliefs, it can be easy to ignore.
That’s no excuse for policy makers and politicians. An improvement on the status quo is not too much to ask. 

More Problems for "Liberation Treatment" Theory

Despite the enthusiasm and attention from Canadian politicians, more problems continue to come to light regarding the theory that CCSVI is the cause of multiple scleroris and that the so-called "Liberation Treatment" represents a cure.
It's an issue I've previously written about.
The latest studies yet again demonstrate that these vein blockages are unlikely to be the cause of MS:

Several new studies are pointing against narrowed neck veins as being the primary culprit in causing multiple sclerosis.
(...)
Now, results of a study that involved Doppler ultrasounds of 499 subjects, led by Dr. Robert Zivadinov of the University of Buffalo, N.Y., have been published in the journal Neurology.
The prevalence of CCSVI was 56 per cent for patients with MS, 42 per cent in patients with other neurologic diseases, 38 per cent in those with clinically isolated syndrome that can be a precursor to MS and 23 per cent in healthy controls.
"Our findings are consistent with an increased prevalence of CCSVI in MS but with modest sensitivity/specificity," the researchers concluded.
"Our findings point against CCSVI having a primary causative role in the development of MS."
(...)
An accompanying editorial in the journal says the study suggests that CCSVI, as defined using ultrasound of the intracranial and extracranial venous system, is not likely to be a primary causal process in MS.
(...)
A number of other smaller studies on the subject were presented this week at the meeting.
A study led by Katayoun Alikhani of Calgary included 67 people at the city's University Hospital who underwent magnetic resonance venography of their neck veins.
Among the findings: vein abnormalities were found in 20 per cent of those with MS and 20 per cent of those without MS.
"This first independent Canadian MRV study confirms neck vein abnormalities are infrequent and independent of the diagnosis of MS," the researchers wrote in their conclusion, noting that larger, controlled, blinded and more comprehensive studies are underway.

Another group in Europe assessed whether the venous drainage from the brain was impaired in 94 patients with MS and 20 healthy control subjects. Their findings provided compelling evidence against a significant role of cerebro-cervical venous congestion in the pathogenesis of MS, they concluded.

 

What's also of note is that Dr. Zivadinov had previously seemed to be quite supportive of Paolo Zamboni's CCVSI theory.

Now these are just the most recent but certainly not the only studies casting doubt on the CCSVI theory. Some of the others include:
This (a study Dr. Zivadinov was also involved in):
No significant differences in the extracranial venous systems between MS patients and HC subjects were detected by using MR venography.
This:
Chronic cerebrospinal venous insufficiency (CCSVI) has been postulated as a cause for multiple sclerosis (MS). Venous pressure assessments have not been made. Intracranial venous pressure was assessed using ophthalmodynamometry in 29 MS patients and compared with 28 healthy controls and 19 cases with elevated intracranial pressure (ICP). MS and control subjects had normal venous pressures (mean 15.5 resp. 15.1 cmHg). Only cases with intracranial pressure pathology had elevated venous pressures (mean 28.8 cmHg). There is no evidence of an increased intracranial venous pressure in MS patients.
This:
This triple-blinded extra- and transcranial duplex sonographic assessment of cervical and cerebral veins does not provide supportive evidence for the presence of CCSVI in MS patients. The findings cast serious doubt on the concept of CCSVI in MS
This:
...we studied 21 relapsing-remitting multiple sclerosis cases and 20 healthy controls with phase-contrast magnetic resonance imaging. In addition, in multiple sclerosis cases we performed contrast-enhanced magnetic resonance angiography. We found no differences regarding internal jugular venous outflow, aqueductal cerebrospinal fluid flow, or the presence of internal jugular blood reflux. Three of 21 cases had internal jugular vein stenoses. In conclusion, we found no evidence confirming the suggested vascular multiple sclerosis hypothesis
This:
Findings suggestive of anomalies of the cranial venous outflow anatomy were frequently observed in both MS patients and healthy controls. Given the normal intracranial venous flow quantification results, it is likely that these findings reflect anatomical variants of venous drainage rather than clinically relevant venous outflow obstructions.
This:
Our results challenge the hypothesis that cerebral venous congestion plays a significant role in the pathogenesis of MS. Future studies should elucidate the difference between patients and healthy subjects in BVF regulation.
This:
Our findings do not support a cause-effect relationship between CCSVI and pMS. Further studies are warranted to clarify whether CCSVI is associated with later disease stages and characterizes the progressive forms of MS.
None of this necessarily closes the door on the CCSVI theory, although it certainly would imply that Zamboni's initial findings are not reliable. More research, though, is warranted to see what if any relationship there is between MS and these blockages. It could be that MS is causing CCSVI as opposed to the other way around.
It's unfortunate, though, that as much attention as the CCSVI theory gets in the media and from politicians, these studies do not seem to be included in much of the coverage.
What's also unfortunate is that other important research on MS (that has nothing to do with CCSVI) seems to get overlooked, as well.

Herald Column: Canadians Deserve Courageous Politicians

My latest Calgary Herald column looks at the moribund election campaign and puts the blame squarely on a lack of political courage on the part of the parties and party leaders:

 

It’s been noted many times that this election seems remarkably devoid of substance. I’d hardly be the first to wonder why so much of what’s passed for debate and discussion on the campaign trail has seemed trivial at best.
It’s easy enough to notice the shallowness of the various political parties, but what seems less fully explored is the reason why there is such an unwillingness to take tough – even controversial - positions on important issues.
However, the explanation may be as simple and straightforward as the observation itself: Canada is suffering from a severe dearth of political courage.
It might be tempting to blame ourselves for this. After all, the politicians who seem to have shunned political courage are after our votes; were Canadians demanding courageous politicians no doubt we’d see them in abundance. Mind you, Canadians haven’t really had the chance to reject courageous politicians, so cause for optimism remains.
It may also be the nature of the beast itself. We’ve got poll-driven election campaigns with politicians so fearful of anything perceived to be a gaffe that it’s become safer to say very little of substance. Much of that is media-driven; campaign coverage often seems pre-occupied with poll-watching and gaffe-hunting rather than exploring the substance of whatever ideas are proposed by candidates or parties.
We saw that in how the Liberals handled some controversial remarks from their candidate in the Alberta riding of Wild Rose. In fact, the Liberals seem to lead all others when it comes to political cowardice.
Take the whole area of law-and-order. There is much wrong with the Conservative approach, and the Liberals on occasion have pointed this out. They have also shown a remarkable tendency for going along with each crime bill the government brings forward.
The Liberals have made much political hay of the enormous costs that might be entailed though the Conservative law-and-order agenda.  However, the Liberals have indicated they will not undo any of the Tories’ crime bills. In other words, the costs they are criticizing are costs they are prepared to swallow themselves – all because they lack to political courage to take a stand.
We see the same cowardice when it comes to the GST. Not that I’m clamouring for a restoration of the GST cuts, but there’s a solid case to be made that it was the wrong tax to cut.
The Liberals have certainly made that case, arguing that the GST cut deprived the government of needed revenue and contributed to the large deficit we now face. There’s a pretty straight downward line to be drawn when it comes to GST revenue.
I realize that in the midst of an election campaign, promising to raise the GST might not seem like brilliant political strategy.
However, if you’re going to criticize the government for cutting the GST then you’d damn well better have the courage to explain why the GST ought to be put back to where it was.
The Conservatives for their part have also shown a disappointing lack of political courage.
In recent days, for example, the issue of federal health transfers has come up on the campaign trail.
After the Liberals proposed an apparently endless six per cent annual escalation in annual health transfers, the Conservatives – rather than point out how reckless and unsustainable the Liberal promise was – simply promised the same thing.
As the chief economist for the Canadian Federation of Independent Business pointed out, a six percent annual increase in health transfers is one-point-five per cent faster than future GDP growth. In other words, we face a major crunch relatively quickly.
The parties’ health promises come just as a new paper was released by the C.D. Howe institute, co-authored by former Bank of Canada governor David Dodge.
The report warns that without major changes, our system is unsustainable, and that we need to have an “adult discussion” about what the report calls a “chronic health-care spending disease”.

One would like to think that Canadians are up for some “adult discussions” about a whole range of important issues. However, because are politicians lack the courage to start such a discussion, we’ll never know for sure.