Spinal Cord Volume Loss in Primary Progressive MS Correlates With Disability

Patients with primary progressive multiple sclerosis (PPMS) demonstrated marked loss of spinal cord volume (SCV) compared with patients with relapse-onset MS, according to a retrospective, longitudinal analysis published in Multiple Sclerosis Journal. 

Furthermore, the loss of SCV correlated with progression of disability symptoms over time. 

For this analysis, 60 patients with MS were selected from an ongoing large-scale cohort study conducted in Basel, Switzerland. Of the study patients, 12 had PPMS, 24 had relapsing-remitting MS (RRMS), and 24 had secondary progressive MS (SPMS). All patients were matched for age, sex, and disease duration.  

This longitudinal study was conducted over 6 years. Clinical and magnetic resonance imaging (MRI) data were collected during annual check-ups. Upper cervical SCV was measured via T1-weighted MRI, and other measured parameters included total brain volume (TBV) and brain T2 lesion volume (T2LV).  The Expanded Disability Status Scale (EDSS) was used for clinical assessment.

Patients with PPMS demonstrated a faster loss of SCV over time compared with patients with RRMS (P <.01).  In addition, SCV loss was faster by trend in PPMS vs RRMS (P =.066).  Unlike in patients with RRMS and SPMS, SCV loss in patients with PPMS was independent of changes in TBV and T2LV.  Furthermore, SCV loss was associated with an increase in EDSS over time (P <.01) in patients with PPMS only. 

“To our knowledge, this is the first longer term follow-up study demonstrating such a striking between-group difference of SCV loss over time,” the investigators wrote. Furthermore, although the study was limited by its small sample size, “[t]he development of SC-related physical disability in our group of PPMS patients in parallel to preferential SCV loss compared with other MS subtypes emphasizes the inclusion of SCV measurements not only as a marker in clinical trials for emerging therapeutic agents, but also in the clinical routine in order to optimize individualized medicine in this patient group,” the investigators noted.

Disclosures: Several authors declare affiliations with the pharmaceutical industry, please refer to the full length text for the complete list. 

Reference

Tsagkas C, Magon S, Gaetano L, et al.  Preferential spinal cord volume loss in primary progressive multiple sclerosis [published online May 21, 2018].  Mult Sler.  doi:10.1177/1352458518775006