Background: Recent natural history studies suggest that MS is a more slowly progressing disease than previously thought. These observations are from studies separated by time, geography and methodological approach.
Epub ahead of print: Shirani et al. Temporal trends of disability progression in multiple sclerosis: findings from British Columbia, Canada (1975-2009). Mult Scler. 2011 Sep 27.
Objectives: The researchers investigated whether MS disease progression has changed over time in British Columbia, Canada.
Methods: The British Columbia MS database was queried for relapsing-onset MS patients with symptom onset from 1975 to <1995, first assessed within 15 years from onset and with at least two Expanded Disability Status Scale (EDSS) scores. Latest follow-up was to 2009. Patients were grouped by 5-year onset intervals (1975 to <1980, 1980 to <1985, 1985 to <1990, 1990 to <1995). Outcome was defined as time to reach sustained and confirmed EDSS 6 within 15 years of disease duration.
Results: A total of 2236 relapsing-onset MS patients (73.4% female; mean age at onset: 32.3 ± 8.8 years) were included. No significant trend was found in the proportion of patients reaching EDSS 6 (needing a walking stick) within 15 years from onset (28.5%, 26.4%, 27.7%, 22.3% for intervals 1975 to <1980, 1980 to <1985, 1985 to <1990, 1990 to <1995, respectively; p = 0.09).
Conclusions: Rates of disease progression remained relatively stable over two decades of MS onset in British Columbia, Canada. Our results suggest that differences in disease progression findings between natural history studies may be related to factors other than time period.
“This is disappointing as we would hope the introduction of DMTs would have an impact on the rate of disease progression.”
“We must not forget that the first-line therapies are not that effective and that too few subjects may have been followed in this cohort too see the impact of DMTs on disease progression rates; i.e. this study was under powered.”
“We will need to wait to see the impact of the next generation of treatments on disease progression. If there is no effect we have got the facts or current dogma about MS wrong.”