People with Primary-progressive MS have steadily worsening symptoms from the outset of their diagnosis, and do not have distinct relapses. Their disability gradually worsens, and it may level off at some point or continue over months or years.
Primary-progressive MS is a progressive form of the disease and does not display any definitive periods of relapse or remission. The age when people first experience this form of the disease is generally older than for other types of MS; PPMS typically affects people in their 40s and onwards (rare cases may occur at an earlier age).
Unlike other forms of MS, PPMS is as likely to occur in men as in women. Initial signs of disease are generally experienced as an increasing spastic gait with an associated decline in quality of walking. Disease prognosis in PPMS is generally poorer than for other types of MS, with quicker deterioration.
Making a definitive diagnosis of PPMS can be difficult and an MRI scan of the brain may not show any evidence of the typical MS plaques, due to their characteristic formation in the spinal cord. It is therefore essential to perform a spinal MRI in order to diagnose this form of MS.
