Objective: To study the long-term outcome and persistence of two patterns of cervical spinal cord abnormality in early relapsing-remitting multiple sclerosis (RRMS).
Methods: RRMS patients with a spinal cord MRI performed during the first 3 years of the disease, a control MRI 5 years later and who have been followed up at least 10 years were included. Patients were grouped according the T2 spinal cord MRI into: (A) nodular pattern, if one or more focal lesions were present; and (B) diffuse pattern, defined as a poorly demarcated high signal area. The end point was defined as the time to reach an Expanded Disability Status Score (EDSS) of 4.0.
Results: Twenty-five patients were included; 12 in group A and 13 in group B. Three patients in group A and 9 in group B reached EDSS 4, in a mean time of 11 years in group A and 7 years in group B (log rank 10.3, p = 0.001). Multivariate Cox regression analysis assessing the risk of EDSS 4.0 including sex, age, number of relapses in the first 2 years, number of T2 brain lesions and spinal cord pattern showed higher risk for the diffuse pattern (hazard ratio 7.2, 95% confidence interval 1.4-36.4). Control MRI showed the persistence of the diffuse pattern in all patients, and the development of diffuse pattern in two patients with basal nodular lesions.
Conclusions: The diffuse abnormality in cervical spinal cord at the beginning of the disease is persistent and predicts a worse prognosis in RRMS patients.