Counting the cost and paying the price are not one and the same. For decades MRI has been the way by which all and sundry have monitored MS disease activity.
But, what does it all mean?
And, how good is it really?
Recently, in a natural history evaluation of MS disease activity, the Barcelona group looked at MRI scans of those presenting to their centre on whom they had at least 10 years of follow up data. This amounted to 401 PwMS.
The figure below is the main finding from their analysis. It demonstrates the risk estimated of reaching a diagnosis of MS (McDonald MS and clinically definite MS or CDMS), EDSS 3.0 and EDSS 6.0 (requiring a stick to walk).
This evaluation is based on the number of T2 lesions on the very first scan.
As you can see a greater number of T2 lesions was associated with an earlier 2nd attack i.e. an MS diagnosis. Whilst, in those with at least 10 lesions at baseline – 30% reached an EDSS of 3.0 and 7% an EDSS of 6.0.
The authors state that these last two figures rose to 39% and 9% respectively if this was the first 15 years of disease.
If you are confused, your confusion is justified. The fact that it’s not enough to simply count lesion numbers on scans as an estimate of the long-term progression risk, is something I’ve suspected for a while now. Furthermore, investigators in said such trials we should question presenting drug efficacy data simply on a reduction in T2 lesion counts pre- and post-treatment. Our outcome measures for this type of evaluation clearly require a shake up.
The long-term outcomes of CIS patients in the Barcelona inception cohort: Looking back to recognize aggressive MS
M Tintore , G Arrambide , S Otero-Romero , P Carbonell-Mirabent , J Río , C Tur , M Comabella , C Nos , M J Arévalo , E Anglada , R Menendez , L Midaglia , I Galán , A Vidal-Jordana , J Castilló , P Mulero , A Zabalza , B Rodríguez-Acevedo , M Rodriguez , C Espejo , J Sequeira , R Mitjana , A de Barros , D Pareto , C Auger , S Pérez-Hoyos , J Sastre-Garriga , A Rovira , X Montalban
Objective: To explore the long-term outcomes of patients with clinically isolated syndromes from the Barcelona cohort.
Methods: We selected patients with a follow-up longer than 10 years to (1) estimate the risks of multiple sclerosis (MS) and disability accumulation according to the baseline number of T2 lesions and to compare treated versus untreated patients and early versus delayed treatment, and (2) to study baseline features of patients with aggressive MS (Expanded Disability Status Scale (EDSS) ⩾6.0 at 10 years).
Results: In all, 401 patients were included (mean follow-up of 14.4 (standard deviation of 2.9) years). A higher number of T2 lesions was associated with an earlier MS diagnosis and an earlier risk of irreversible disability. Early treatment was associated with a decreased risk of EDSS of 3.0: adjusted hazard ratio = 0.4, 95% confidence interval = (0.2, 0.7). Patients with aggressive MS differed in their baseline brain magnetic resonance images: The median (interquartile range) number of T2 lesions and contrast-enhancing lesions (CEL) was 71 (28–95) versus 7 (1–19) and 3 (1–24) versus 0 (0–1), respectively. The cut-offs that better classified patients with aggressive MS were 20 for T2 lesions and 2 for CEL.
Conclusion: Although MS natural history is changing, a high lesion load at onset is helpful to identify patients at risk of presenting an aggressive MS.