INTENS-K

Intensive speech therapy to address bulbar problems in children with neuromuscular disorders

Background: Swallowing and speech difficulties are common and progressive in children with neuromuscular disorders, limiting their social participation and quality of life. In clinical practice, speech and language therapy for children with Duchenne muscular dystrophy (DMD) and myotonic dystrophy type 1 (DM1) often focuses on compensatory strategies, such as avoiding certain foods or reducing speech rate. Although training of orofacial muscles and speech functions may offer a more proactive approach, evidence regarding its effectiveness remains limited. Therefore, there is a need to investigate whether intensive speech and language therapy can stabilize or reduce swallowing and speech difficulties in this population.

Hypothesis: The hypothesis is that intensive speech and language therapy will stabilize or improve orofacial muscle quality in children with DMD and DM1. Furthermore, we expect improvements in speech intelligibility and communicative participation, as well as stabilization of maximum bite force, suprahyoid muscle strength, and chewing and swallowing function.

Approach: This study uses a mixed methods design, combining a prospective exploratory intervention study with qualitative evaluation. Fifty children aged 5 – 18 years (25 with DMD and 25 with DM1) will participate. The intervention consists of 8 weeks of intensive speech and language therapy focusing on orofacial muscle strength training, articulation therapy, and chewing and swallowing exercises, followed by 10 months of maintenance exercises. Children will receive therapy twice weekly and practice at home with parental support using Physitrack.

Quantitative assessments will be conducted at baseline (T0), immediately after the 8-week intervention (T1), and 10 months post-intervention (T2). The primary outcome is change in orofacial muscle quality, measured using quantitative muscle ultrasound. Secondary outcomes include chewing and swallowing function, maximum bite force, severity of dysarthria, speech intelligibility, communicative participation, and swallowing-related quality of life. Outcomes will be compared with data from retrospective longitudinal studies. The qualitative component consists of semi-structured interviews to explore experiences of children and parents/caregivers, and a focus group to get insights into speech and language therapists’ experiences.

Expected results: The expectation is that intensive speech and language therapy will stabilize or improve orofacial muscle quality and functional outcomes, leading to enhanced speech intelligibility, communicative participation, and maintenance of chewing and swallowing function. This study will provide important evidence on the effectiveness and feasibility of intensive therapy in children with DMD and DM1.

Awarded grant: €275.000