Voice Characteristics and Parent-Reported Voice Handicap in Children With Mucopolysaccharidosis: A Pilot Case-Control...

Mucopolysaccharidoses (MPS) are inherited lysosomal storage disorders characterized by glycosaminoglycan accumulation and multisystem involvement. Ear, nose, and throat manifestations are common and may appear early; however, pediatric voice characteristics in MPS remain under-described.

To compare acoustic and cepstral voice measures, maximum phonation time (MPT), and parent-reported voice-related handicap (Pediatric Voice Handicap Index-pVHI) between children with MPS and age- and sex-matched typically developing peers, and to describe upper-airway and laryngeal mucosal alterations based on videoendoscopic findings as part of a multidimensional assessment. A secondary aim was to explore differences between MPS type IV and MPS type VI.

Seventeen children with MPS (type IV, n = 10; type VI, n = 7) and 17 age- and sex-matched controls with normal hearing were included. Sustained /a/ phonation was recorded for acoustic analysis using perturbation-based measures (MDVP) and cepstral-spectral analysis (analysis of dysphonia in speech and voice; cepstral peak prominence [CPP]). MPT was measured across three trials (mean used for analysis). Parents completed the Pediatric Voice Handicap Index (pVHI). Flexible upper-airway and laryngeal videoendoscopy was performed, and recordings were reviewed by study laryngologists using a disease-specific classification system for mucosal alterations in mucopolysaccharidosis, with consensus procedures applied in cases of discrepant ratings.

Compared with controls, children with MPS demonstrated reduced MPT and increased noise-to-harmonics ratio. After applying domain-specific Holm-Bonferroni correction, voice turbulence index and CPP also remained statistically significant. No significant differences were found for fundamental frequency, jitter, shimmer, or CPP variability. Children with MPS exhibited substantially higher voice-related handicap. No statistically meaningful differences were observed between MPS type IV and type VI.

Findings from this preliminary study, which combined parent-reported voice handicap and acoustic analysis, underscore the importance of incorporating routine voice assessments into the multidisciplinary management of individuals with MPS.