Open Access Research article

Disease-modifying drug initiation patterns in commercially insured multiple sclerosis patients: a retrospective cohort study

Jay M Margolis1*, Robert Fowler2, Barbara H Johnson2, Cheryl A Kassed3 and Kristijan Kahler4

Author Affiliations

1 Thomson Reuters, 332 Bryn Mawr Ave., Bala Cynwyd, PA, 19004, USA

2 Thomson Reuters, 4301 Connecticut Ave NW, Suite 330, Washington, DC, 20008, USA

3 Health Analytics, LLC, 9200 Rumsey Road, Suite 215, Columbia, MD, 21045, USA

4 Novartis Pharmaceuticals, One Health Plaza, USEH 501/399O, East Hanover, NJ, 07936, USA

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BMC Neurology 2011, 11:122  doi:10.1186/1471-2377-11-122

Published: 6 October 2011



The goal of this research was to compare the demographics, clinical characteristics and treatment patterns for newly diagnosed multiple sclerosis (MS) patients in a commercial managed care population who received disease-modifying drug (DMD) therapy versus those not receiving DMD therapy.


A retrospective cohort study using US administrative healthcare claims identified individuals newly diagnosed with MS (no prior MS diagnosis 12 months prior using ICD-9-CM 340) and ≥ 18 years old during 2001-2007 to characterize them based on demographics, clinical characteristics, and pharmacologic therapy for one year prior to and a minimum of one year post-index. The index date was the first MS diagnosis occurring in the study period. Follow-up of subjects was done by ICD-9-CM code identification and not by actual chart review. Multivariate analyses were conducted to adjust for confounding variables.


Patients were followed for an average of 35.7 ± 17.5 months after their index diagnosis. Forty-three percent (n = 4,462) of incident patients received treatment with at least one of the DMDs during the post-index period. Treated patients were primarily in the younger age categories of 18-44 years of age, with DMD therapy initiated an average of 5.3 ± 9.1 months after the index diagnosis. Once treatment was initiated, 27.7% discontinued DMD therapy after an average of 17.6 ± 14.6 months, and 16.5% had treatment gaps in excess of 60 days.


Nearly 60% of newly-diagnosed MS patients in this commercial managed care population remained untreated while over a quarter of treated patients stopped therapy and one-sixth experienced treatment gaps despite the risk of disease progression or a return of pre-treatment disease activity.