The challenges of measuring disability accumulation in relapsing–remitting multiple sclerosis: evidence from interferon beta treatments

Abstract

Irreversible disability is the critical long-term consequence of multiple sclerosis (MS). While there are well-established measures for disability in MS, they have limitations that may affect our perception of disease progression either due to the empirical nature of some assessments or the lack of validation with long-term outcomes. Measuring effects on disability accumulation in relapsing–remitting MS is also difficult in clinical trial situations because of the protracted evolution of the disease and the ethical and practical implications of long-term placebo-controlled trials, which may have implications for clinicians considering treatment options. Despite these issues, interferon-beta therapies have decades of follow-up data, with which it is possible to evaluate prognostic factors for the accumulation of disability in relapsing–remitting MS.

Keywords::

• disability measures
• EDSS
• interferon beta
• MSFC
• multiple sclerosis

Financial & competing interests disclosure

BC Kieseier has received honoraria from Bayer Schering, Biogen Idec, Medac, Merck Serono, Novartis, Sanofi, Talecris, and Teva and research support from Bayer Schering, Biogen Idec, Biotest, Merck Serono, and Teva. The work was funded by Biogen Idec Inc. The author retained full editorial control. The author has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Medical writing assistance was provided by Simon Whiteley and editorial support was provided by J Cannon and J Safran, all of Infusion Communications.

Key issues

• Accumulated clinical experience with interferon-beta (IFNβ) over 20 years in patients with multiple sclerosis suggests that early initiation and long duration of treatment translate into meaningful clinical endpoints in patients suffering from this disabling disease.

• Finding the right therapy for the individual patient at the right time remains a challenging task for the treating neurologist.

• The assessment of clinical disability is key to treatment decision pathways in clinical practice.

• The Expanded Disability Status Scale and Multiple Sclerosis Functional Composite, as well as magnetic resonance imaging, may be helpful in predicting an individual’s clinical course.

Notes