Primary <scp>P</scp>rogressive <scp>M</scp>ultiple <scp>S</scp>clerosis <scp>E</scp>volving <scp>F</scp>rom <scp>R</scp>adiologically <scp>I</scp>solated <scp>S</scp>yndrome

Abstract

Subjects with RIS evolve to PPMS at the same frequency as expected from general MS populations in an age-dependent manner. Besides age, unequivocal presence of spinal cord lesions and being male predicted evolution to PPMS. Our findings further suggest that RIS is biologically part of the MS spectrum.