A large Canadian study has shown that people treated with interferons progressed to disability just as quickly as those not treated, raising serious doubts about the use.

Scientists and clinicians treating MS have long had concerns about the assumption made after the early interferon studies were published in the 1990s that the 30% reduction in relapse rates and reduced inflammatory activity in the central nervous system (CNS) demonstrated in these short term clinical trials translated into long term benefit. The studies were unable to show any slowing of the progression of the disease to disability, and it was assumed that this was because the trials were only of short duration, and therefore didn't detect a real benefit in slowing disease progression. A large, well-conducted study from British Columbia in Canada published in one of the world's leading medical journals has shown that the assumption of long term benefit based on these short term trials was incorrect. In fact, in following 868 people with MS treated with interferons over time, and comparing them with 829 untreated people from the same time period and 959 untreated people from an earlier period, there was no difference in the time taken to require a cane to walk 100m for people treated with interferon compared to those not treated.

Expert neurologists commenting on the study in an accompanying editorial agreed with the authors that the study could find no evidence that the interferons reduced the progression of the disease to disability. This is sobering news for those people offered or taking these medications, particularly as the authors of the editorial rightly note that "the majority of—but not all—patients with MS develop severe disability 10 to 20 years after diagnosis'. But the editorial goes on to say that "Lacking evidence of treatment effect is not proof of lacking effect", meaning that the drugs may still work, even though we are unable to demonstrate this in well-designed and conducted studies. This is an amazing assertion, given that these medications cost tens of thousands of dollars annually, and are generally taken for life. Surely we require good evidence of benefit before prescribing costly medicines with potentially serious side effects!

Strangely, this argument is not used when it comes to diet. Most authorities would say that lack of evidence of a benefit from diet in MS (according to these experts) means that diet does not work. At OMS we are much more impressed with the research conducted by neurologists like Prof Swank, published in the Lancet, showing decades of disability-free living for a large cohort of people with MS sticking to a very low saturated fat diet. 

The paper is free online at http://jama.jamanetwork.com/article.aspx?articleid=1217239 and the editorial can be downloaded in pdf format above right. The editorial particularly is worth reading in full. Surprisingly, the authors assert that: "it is likely that neurologists will continue to prescribe interferon beta and other interferons and patients with relapsing-remitting MS will continue to self-inject these agents, relying on the available evidence from controlled studies about short-term benefits". Coming from doctors who demand evidence when it comes to such things as diet, meditation, exercise, etc (for which incidentally there is a wealth of solid evidence), this is a staggering statement. We hope that neurologists everywhere will reconsider the long term use of these costly medications.