Spinal Cord Atrophy in Multiple Sclerosis: A Systematic Review and Meta-Analysis

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Spinal cord atrophy (SCA) is an emerging outcome measure in multiple sclerosis (MS).
• Limited consensus exists regarding the extent and rate of SCA in MS.
• This study synthesizes available data on SCA measures in MS.

Purpose of the Study:

• To synthesize available data on measures of spinal cord atrophy (SCA) in multiple sclerosis (MS).
• To establish a consensus on the magnitude and rate of SCA in MS.
• To evaluate SCA as an outcome measure in MS clinical trials.

Main Methods:

• Literature databases were searched (1977-2017) for studies reporting quantitative SCA measures in MS patients.
• Random-effects models were used to pool cross-sectional and longitudinal SCA data from MS patients and healthy controls (HCs).
• Statistical analyses included Student's t-test for subgroup comparisons and heterogeneity assessment using Q-test and I²-index.

Main Results:

• 94 studies met inclusion criteria, analyzing 1,465 retrieved studies.
• Pooled cervical spinal cord cross-sectional area (CSA) was significantly smaller in MS patients (73.07 mm²) compared to HCs (80.87 mm²).
• The pooled annual rate of SCA was 1.78%/year, correlating with disability (r-values range: -0.75 to -0.22).

Conclusions:

• Spinal cord atrophy is a significant finding in MS, more pronounced in progressive forms than relapsing forms.
• SCA magnitude correlates with clinical disability.
• The rate of SCA in MS exceeds reported rates of brain atrophy, underscoring its relevance for MS clinical trials.