In patients with multiple sclerosis (MS), extensive cortical damage at onset is associated with florid inflammatory clinical activity and increases the risk for rapid occurrence of the progressive phase, according to results published in Neurology.
Risk factors that can help identify high-risk patients include age at onset, the number of early attacks, and the extent of baseline focal cortical damage. These patients may benefit from more active therapy.
The study included participants with relapsing-remitting MS (RRMS; n=219). The researchers assessed the number of cortical lesions, the number of white matter lesions, and cortical thickness at baseline and after 7.9 mean years of follow-up.
In 6.1 mean years, 27% of participants (n=59) converted to secondary progressive MS (SPMS).
A larger number of cortical lesions at baseline predicted a higher risk for SPMS (hazard ratio [HR] 2.16, 4.79, and 12.3 for 2, 5, and 7 cortical lesions, respectively; P <.001) and shorter latency to progression.
Participants with ≥3 early relapses had a larger volume of white matter and cortical lesions at onset, accrued more cortical lesions, experienced more severe cortical atrophy over time, and entered the SPMS phase more rapidly compared with participants with 1 or 2 early relapses.
In the multivariate model, older age at onset (HR 1.97; P<.001), larger baseline cortical lesion volume (HR 2.21; P =.005), larger baseline white matter lesion volume (HR 1.32; P =.03), early changes in global cortical thickness (HR 1.36; P =.03), and ≥3 early relapses (HR 6.08; P <.001) independently predicted a higher probability of SPMS.
Scalfari A, Romualdi C, Nicholas RS, et al. The cortical damage, early relapses, and onset of the progressive phase in multiple sclerosis. [published online May 16, 2018]. Neurology. doi:10.1212/WNL.0000000000005685.