Multiple sclerosis (MS) is a complex, recurrent, and progressive autoimmune disease of the central nervous system affecting an estimated 250,000 to 400,000 people in the US. Primarily diagnosed in young adults at a mean age of 29 years, it follows four recognized disease courses: relapsing/remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS), and progressive relapsing MS (PRMS) [1–4]. Approximately 20% of patients have a mild form of the disease, yet MS can also render a person unable to write, speak, or walk, with up to 60% of patients losing ambulatory capability within 20 years after onset [1, 2, 5]. Since most people with MS have a fairly normal life expectancy, this chronic disease evokes very significant social, medical and economic impacts.
MS is neither easy nor quick to diagnose, especially in its early stages, compounded by the often transient nature of attacks, variability in symptoms, other diseases producing similar symptoms, and the lack of a specific unequivocal diagnostic test [1–4, 6, 7]. Clinical diagnosis often requires several strategies to determine if a person meets the established criteria (e.g., The Revised McDonald Criteria), including a detailed medical history, neurologic exams, magnetic resonance imaging (MRI), evoked potentials (EP) and spinal fluid analysis [7–9]. Symptoms may vary in frequency, severity and form, and so patients diagnosed with clinically definite MS will typically have been through several diagnostic stages often drawn out over months or years [10–17].
There is presently no known cure for MS. Current treatments for MS are aimed at returning function after an attack, preventing new attacks, managing symptoms and preventing or postponing long-term disability . Acute symptomatic attacks are most often treated with high dose glucocorticoids, however there does not appear to be any long-term functional benefit from their use [18, 19]. Several disease-modifying drugs (DMDs) have been found to reduce the relapse rate, reduce lesion development, positively affect MRI metrics and disease progression, and improve the quality of life for many MS patients [3, 18, 20–23]. Six parenterally administered DMDs are currently approved for immunomodulatory and immunosuppressive treatment of relapsing and secondary-progressive MS (in alphabetical order): glatiramer acetate, interferon beta 1a--intramuscular, interferon beta 1a--subcutaneous, interferon beta 1b, mitoxantrone, and natalizumab . DMD treatment can be sustained indefinitely, as long as there is evidence of benefit, particularly since cessation of therapy may result in returning to pre-treatment disease activity [21, 24–29].
The decision to begin or continue MS therapy is complex and controversial . The National Multiple Sclerosis Disease Management Consensus Statement  recommends initiating interferon beta or glatiramer DMD therapy as soon as possible following definite diagnosis of active, relapsing MS, and also to consider DMD therapy for selected high risk patients with a first attack. Although the DMDs have positively affected the treatment and course of RRMS, numerous factors including their parenteral route of administration, injection anxiety, side effects, unobservable improvement, adjunctive therapy, and treatment fatigue can affect the initiation and continuation of DMD therapies [5, 17, 23, 25–29].
The objective of the current research was to understand the differences in demographics, clinical characteristics and treatment patterns between newly diagnosed MS patients in a commercial managed care population who received DMD therapy versus those not receiving DMD therapy.