Researchers used novel statistical methods to study outcomes for 1178 people with MS from three MS centers in Italy, and concluded that using disease-modifying therapies significantly reduced the risk of progressing from relapsing-remitting
MS. Roberto Bergamaschi, MD (Neurological Institute C. Mondino, Pavia, Italy) and colleagues report their findings in MS Journal (2012 May 31. [Epub ahead of print]
). This novel, investigator-initiated study adds to the body of evidence suggesting that MS therapies improve future outcomes for people with MS.
Multiple sclerosis occurs when the immune system attacks the brain and spinal cord. Several treatments, called disease-modifying therapies
(DMDs), are available that can reduce the inflammation associated with the immune attack and reduce disease activity.
The effect of these therapies on damage to nerve fibers is not well understood, and it is unknown to what extent they reduce the progression of MS, which is associated with nerve fiber damage, beyond what is reported from relatively short-term clinical trials. Some of the difficulties involved in answering this question using traditional, randomized clinical trials include that it would take a long time to observe effects on progression, and that the conditions of a trial do not necessarily reflect how the ‘real world’ affects disease progression.
These researchers took a novel approach to analyze data and outcomes related to 1178 people who had MS for 10 or more years and were examined at one of three MS centers in Italy. Of these, 478 had received no prior MS treatment; 700 had been treated with disease-modifying therapies of any type, including 606 who had taken interferons or glatiramer acetate. The researchers focused many of their comparisons on this group rather than the smaller number who had been on other therapies such as natalizumab, mitoxantrone or fingolimod.
The researchers used a measure of how many people shifted from relapsing-remitting MS to secondary-progressive MS. Following an initial period of relapsing-remitting MS, many people develop a secondary-progressive disease course in which the disease worsens more steadily, with or without occasional flare-ups, minor recoveries (remissions), or plateaus. In this study, secondary-progressive MS was considered to have begun after an individual experienced continuing deterioration without a relapse or remission, for at least one year, severe enough to lead to an increase of at least one point on the EDSS disability scale.
The investigators found that those who had received treatment were significantly less likely to have shifted to secondary-progressive MS. At 10 years, 382 out of 478 (79.9%) who had not been treated still had RR MS, and 96/478 (20.1%) had developed SP MS. Of those treated with interferons or glatiramer acetate, 585/606 (97%) still had RR MS and 21/606 (3%) had developed SP MS.
The team designed a novel statistical method that incorporated clinical factors collected within the first year of disease. These factors indicated whether people were at high risk or low risk for progressing from relapsing-remitting to secondary-progressive MS. In evaluating these factors, the risk of progression to secondary-progressive MS was reduced in people who took DMDs – both in people at high risk and at low risk for progression.
This novel study adds to the body of evidence suggesting that MS therapies improve future outcomes for people with MS, having a positive effect not only on inflammation but also on the damage to nerve tissues that causes progression of disability over time. The study requires further confirmation, but it indicates the value of pursuing every novel avenue to answer the tricky questions posed by MS.