Restless legs syndrome as a comorbidity in amyotrophic lateral sclerosis: a systematic review and meta-analysis

Restless Legs Syndrome (RLS), characterized by an urge to move the legs, is linked to neurodegenerative diseases. Emerging evidence suggests a higher RLS prevalence in Amyotrophic Lateral Sclerosis (ALS), impacting quality of life. However, there is lack of comprehensive review addressing its prevalence and associated risk factors. This meta-analysis estimates RLS prevalence in ALS patients compared to healthy controls.

We searched PubMed, Embase, Web of Science, and Scopus for studies assessing RLS in ALS patients versus controls, adhering to PRISMA guidelines. Two reviewers independently extracted data and assessed bias using Joanna Briggs Institute (JBI) checklist. Meta-analysis used Comprehensive Meta-Analysis software with a random-effects model due to heterogeneity. The certainty of evidence was appraised using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) framework.

Out of 291 studies, eight studies (792 ALS, 716 controls) were included. The pooled RLS prevalence in ALS was 17% (95% CI: 14.0%-21.1%; I²: 56.5%; p-value < 0.001). The fixed effect meta-analysis of four studies indicated that the difference of RLS prevalence was statically significant between patients with ALS and healthy controls (OR: 5.65; CI: 2.86-11.13; P-value < 0.001; I²: 28.7.).

RLS is significantly more prevalent in ALS patients, potentially worsening sleep and quality of life, mental health, and social well-being. Therefore, it is essential to draw clinicians' attention to RLS in ALS patients due to its potential impact on overall health.