Motor Function Characteristics of Adults With Late-Onset Pompe Disease

Abstract

Background and objectives:Pompe disease is a rare neuromuscular disease caused by a deficiency of the lysosomal enzyme GAA. The late-onset of Pompe disease (LOPD) in adults is characterized by weakness of ventilatory, axial and proximal extremity muscles. These muscle impairments progressively impair various motor functions such as locomotion and postural control. Nearly 87% of adults with LOPD report walking problems and over 80% report instability and falls. Knowledge of these motor functions is now sufficient to provide a clear and comprehensive overview of motor function in adults with LOPD. Therefore, this scoping review aimed to summarize current knowledge about motor function in adults with LOPD. It specifically targeted neuromuscular performance, locomotion and postural control.Methods:A systematic search in MEDLINE (via PubMed), EMBASE and Cochrane databases was conducted until May 2021. We included studies providing primary data on at least four participants exploring neuromuscular performance, locomotion and/or postural control in adults with LOPD. Risk of bias analysis was assessed using tools appropriate to the study designs; ROB 2.0 for randomized controlled trials, ROBIN-I for non-randomized interventional trials, and NOS for cohort studies and case controls.Results:The search identified 2,885 articles. After screening, 58 articles were included in the analysis. In these studies, 88% explored locomotion, 83% neuromuscular performance and 3% postural control. This review showed that adults with LOPD have symmetrical weakness, concerning especially the hip and lumbar muscles. Locomotor activities are limited with a distance reduction, spatiotemporal gait parameter modification and an increased pelvic drop and tilt. Balance disorders are also observed especially in the anteroposterior direction.Discussion:We performed the first review on motor function characteristics in adults with LOPD. Although a significant amount of knowledge was synthesized in this review, our study also highlighted the lack of current research on this topic. Maximal muscle strength was the only neuromuscular performance studied and gait biomechanics and postural control were poorly explored in LOPD. Relationships between the degree of muscle weakness and motor function alterations also remains to be determined in adults with LOPD.