Prevalence of dysarthria in the multiple sclerosis population: A systematic review and meta-analysis

Introduction

Dysarthria is a common type of motor speech disorder seen in people with MS (PwMS), with studies reporting a prevalence ranging from 40 % to 51 %. There is inconsistent evidence regarding its specific prevalence and its potential association with disability progression and disease duration.

Methods

This systematic review and meta-analysis aims to estimate the prevalence of dysarthria in PwMS and to explore potential associations between dysarthria and demographic and disease-specific factors. Adhering to PRISMA guidelines, a detailed search of the MEDLINE PubMed, Cochrane Library, and Scopus databases was conducted.

Results

A total of 14 studies involving 1833 MS patients were included, revealing a pooled prevalence of dysarthria in MS of 44.9 % (95 % CI [31.9,58.2], I2=96.2 %, p < 0.00). The aggregated risk ratio of speech disorders in MS patients versus healthy controls was 8.09 (95 %CI [2.40, 27.26], pz=0.0007, I²=53 %, p = 0.05. However, meta-regression sensitivity analysis showed no statistically significant associations between speech disorders and age, or disability level but there was evidence of an anti proportional linear relationship between the prevalence of speech disorders and disease duration (p = 0.1)

Conclusion

This systematic review and meta-analysis found a 44.9 % prevalence of dysarthria in the MS population; however, no relationship could be established between dysarthria and demographic and disease-specific characteristics. Considering the impact of dysarthria in the quality of life in PwMS, as well as the diagnostic limitations currently existing in clinical practice, this study highlights the necessity for future studies to, systematically and accurately, record dysarthria symptomatology and aetiology in PwMS.