60/30: 60% of the Morbidity-Associated Multiple Sclerosis Disease Burden Comes From the 30% of Persons With Higher Impairments

Marco Kaufmann; Milo Alan Puhan; Anke Salmen; Christian P Kamm; Zina-Mary Manjaly; Pasquale Calabrese; Sven Schippling; Stefanie Müller; Jens Kuhle; Caroline Pot; Claudio Gobbi; Nina Steinemann; Viktor von Wyl; Swiss Multiple Sclerosis Registry (SMSR)

doi:10.3389/fneur.2020.00156

60/30: 60% of the Morbidity-Associated Multiple Sclerosis Disease Burden Comes From the 30% of Persons With Higher Impairments

Front Neurol. 2020 Mar 6:11:156. doi: 10.3389/fneur.2020.00156. eCollection 2020.

Authors

Marco Kaufmann¹, Milo Alan Puhan¹, Anke Salmen², Christian P Kamm^{2

3}, Zina-Mary Manjaly^{4

5}, Pasquale Calabrese⁶, Sven Schippling^{7

8}, Stefanie Müller⁹, Jens Kuhle¹⁰, Caroline Pot¹¹, Claudio Gobbi^{12

13}, Nina Steinemann¹, Viktor von Wyl¹; Swiss Multiple Sclerosis Registry (SMSR)

Affiliations

¹ Department of Epidemiology, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland.
² Department of Neurology, Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland.
³ Neurology and Neurorehabilitation Centre, Luzerner Kantonsspital, Lucerne, Switzerland.
⁴ Department of Neurology, Schulthess Clinic, Zurich, Switzerland.
⁵ Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.
⁶ Division of Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.
⁷ Neuroimmunology and Multiple Sclerosis Research, Department of Neurology, University Hospital Zurich and University of Zurich, Zurich, Switzerland.
⁸ Center for Neuroscience Zurich, University of Zurich and Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland.
⁹ Department of Neurology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
¹⁰ Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, Switzerland.
¹¹ Service of Neurology, Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
¹² Faculty of Biomedical Sciences, Università della Svizzera Italiana (USI), Lugano, Switzerland.
¹³ Department of Neurology, Multiple Sclerosis Center (MSC), Neurocenter of Southern Switzerland, Lugano, Switzerland.

Abstract

Background: Multiple sclerosis (MS) is the most common chronic, non-traumatic, neurologic disease in young adults. While approximate values of the disease burden of MS are known, individual drivers are unknown. Objective: To estimate the age-, sex-, and disease severity-specific contributions to the disease burden of MS. Methods: We estimated the disease burden of MS using disability-adjusted life years (DALYs) following the Global Burden of Disease study (GBD) methodology. The data sources consisted of the Swiss MS Registry, a recent prevalence estimation, and the Swiss mortality registry. Results: The disease burden of MS in Switzerland in 2016 was 6,938 DALYs (95%-interval: 6,018-7,955), which corresponds to 97 DALYs per 100,000 adult inhabitants. Morbidity contributed 59% of the disease burden. While persons in an asymptomatic (EDSS-proxy 0) and mild (EDSS-proxy >0-3.5) disease stage represent 68.4% of the population, they make up 39.8% of the MS-specific morbidity. The remaining 60.2% of the MS-specific morbidity stems from the 31.6% of persons in a moderate (EDSS-proxy 4-6.5) or severe (EDSS-proxy ≥7) disease stage. Conclusions: Morbidity has a larger influence on the disease burden of MS than mortality and is shared in a ratio of 2:3 between persons in an asymptomatic/mild and moderate/severe disease stage in Switzerland. Interventions to reduce severity worsening in combination with tailored, symptomatic treatments are important future paths to lower the disease burden of MS.

Keywords: DALY; SMSR; burden; epidemiology; morbidity; mortality.