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Published on: December 9, 2015
Clinical course of multiple sclerosis: A nationwide cohort study
Ali Manouchehrinia1, Omid Beiki2, Jan Hillert1
1Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Background:
The course of multiple sclerosis (MS) has been studied in several cohorts; however, results have varied significantly.
Objective:
To describe the clinical course of MS in a nationwide cohort of patients.
Method:
Data from the Swedish MS register (SMSreg) were used to estimate the median time to the sustained Expanded Disability Status Scale (EDSS) scores 3.0, 4.0 and 6.0, onset of secondary progressive multiple sclerosis (SPMS) and death using Kaplan-Meier method. A possible effect of first-line treatments on age at EDSS 6.0 and SPMS was estimated.
Results:
In all, 12,703 patients were included. Median ages at EDSS scores 3.0, 4.0 and 6.0 were 55.4 (95% confidence interval (CI): 54.8-55.8), 60.7 (95% CI: 60.1-61.2) and 64.3 (95% CI: 63.6-64.7), respectively. Median age at SPMS was 57.4 (95% CI: 56.9-57.9). The median age at the time of death was 80.5 (95% CI: 79.9-81.1). Males and progressive-onset patients showed higher risks of disability worsening. On average, treated patients gained 1.6 years (95% CI: 0.2-3) to EDSS 6.0 as a result of treatment.
Conclusion:
Ages at disability milestones in this population-based cohort were higher than previously described in clinic- and regional-based samples. Nevertheless, MS patients die at younger age and live at an average almost 20 years with moderate and 30 years with severe disability.
Insights
This nationwide study found that multiple sclerosis (MS) patients reach disability milestones later than previously reported. However, MS significantly impacts lifespan and years lived with disability.
Area of Science:
- Neurology
- Epidemiology
- Clinical Research
Background:
- Previous studies on multiple sclerosis (MS) clinical course show significant variability.
- Understanding the disease trajectory in large, representative populations is crucial for accurate prognosis and patient care.
Purpose of the Study:
- To characterize the clinical course of MS within a comprehensive nationwide cohort.
- To establish median ages for key disability milestones and survival in Swedish MS patients.
Main Methods:
- Utilized data from the Swedish MS register (SMSreg) for 12,703 patients.
- Employed Kaplan-Meier methods to estimate time to Expanded Disability Status Scale (EDSS) 3.0, 4.0, 6.0, secondary progressive MS (SPMS), and death.
- Assessed the potential impact of first-line treatments on age at EDSS 6.0 and SPMS onset.
Main Results:
- Median ages: EDSS 3.0 (55.4 years), EDSS 4.0 (60.7 years), EDSS 6.0 (64.3 years), SPMS onset (57.4 years), and death (80.5 years).
- Higher risk of disability worsening observed in males and patients with progressive onset.
- First-line treatments were associated with a median gain of 1.6 years to reaching EDSS 6.0.
Conclusions:
- Disability milestones in this nationwide cohort occurred at later ages compared to previous clinic- or region-based studies.
- Despite later milestones, MS patients experience reduced lifespan and prolonged periods with moderate (approx. 20 years) and severe (approx. 30 years) disability.
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