1Amirreza Naseri, 1Ehsan Nasiri, 2Mohammad Ali Sahraian, 3Sara Daneshvar, 3Mahnaz Talebi

1Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran; 2Sina MS Research Center, Sina hospital, and department of neurology, Tehran University of Medical Sciences,, Tehran, Iran; 3Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran

Background:

Multiple sclerosis (MS) commonly affects young adults at the ages 20 to 40 years old, but it can onset at each age. Late-onset multiple sclerosis (LOMS) is defined as symptoms initiating after the age of 50. Because of similar manifestations between LOMS and other diseases of the elderly, misdiagnosis and a remarkable gap in diagnosis of LOMS is a challenge of the elderly population (1, 2). Since its technical development in the early 1980s, magnetic resonance imaging (MRI) has quickly been adopted as an essential tool in supporting the diagnosis, longitudinal monitoring, evaluation of therapeutic response, and scientific investigations in MS (3). In this systematic review, we elevate the MRI profiles of LOMS cases, based on published studies. As spinal cord involvement is an important cause of disability in patients with MS (4), we also investigated the proportion of spinal cord involvement in LOMS cases.

Material(s) and Method(s):

MEDLINE via PubMed, EMBASE, and Scopus databases were searched with the “multiple sclerosis, MS, late onset and LOMS” keywords, on November, 2020, with no restrictions and updated via hand searching in October 2021. Two independent researchers screened the records in title/abstract and full-text stages and extracted the data using a data extraction table. The meta-analysis was conducted using the Comprehensive Meta-Analysis (CMA) with 95% confidence intervals and 0.05 level of significance for p-value.

Result(s):

733 records were screened in the title/abstract and 70 studies in full-text stages and finally 16 studies were included in this systematic review (figure1). In one of the included studies in a Canadian setting, spinal cord involvement was seen in 100% of patients, but this study was limited by size (n= 12) and the age of patients was above 60 in time of diagnosis of MS. On the other hand, the lowest spinal cord involvement (29.1%) belonged to a study in an Iranian setting with 48 patients. The details of included studies are reported in table 1. Based on the meta-analysis in random effect model 65.4% (95% CI: 49.7% to 78.3%) of LOMS casas had spinal cord involvements with 89.79% I2 heterogeneity (p-value <0.01) (figure2).

Conclusion(s):

There is a significant rate of spinal cord involvement in LOMS cases, which can cause a significant disability in MS patients and affect the patients’ quality of life. Improvement in MRI techniques has allowed a better assessment of correlation between the clinical and radiological parameters. Not only does MRI identify MS-like lesions, but it also excludes other potentially mimicking pathologies, so increasing the knowledge regarding the MRI finding of LOMS cases, can help clinician in timely diagnosis of the disease.