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Published on: October 13, 2023
Late-onset multiple sclerosis in Isfahan, Iran.
Masoud Etemadifar1, Seyed-Hossein Abtahi, Alireza Minagar
1Medical School, Isfahan University of Medical Sciences, Isfahan, Iran.
Archives of Iranian Medicine
|October 2, 2012
Summary
Late-onset multiple sclerosis (LOMS) affects 1.36% of patients, with a higher male frequency and faster progression than typical MS. LOMS cases showed more primary progressive patterns and higher progression indices.
Area of Science:
- Neurology
- Epidemiology
Background:
- Multiple sclerosis (MS) typically affects young adults.
- Late-onset MS (LOMS) is defined as initial symptoms appearing after age 50.
Purpose of the Study:
- To determine the frequency and characteristics of LOMS in the Isfahan MS Society (IMSS) cohort.
- To compare LOMS patients with non-LOMS individuals.
Main Methods:
- Retrospective analysis of 3522 MS patient records from the IMSS (2003-2010).
- Identification and comparison of 48 LOMS cases with 1698 non-LOMS subjects.
Main Results:
- LOMS frequency was 1.36%, with a higher prevalence in males (2.4%) than females (1.0%).
- The female to male ratio in LOMS was 1.4:1, significantly lower than in non-LOMS (3.37:1).
- LOMS patients exhibited a higher mean progression index (0.88) compared to non-LOMS (0.37) and a greater frequency of primary progressive MS.
Conclusions:
- LOMS is characterized by a higher frequency of the primary progressive pattern and a higher progression index compared to non-LOMS.
- LOMS constituted a smaller proportion of the total MS population in Isfahan compared to other high-risk populations.
