Functional performance and muscular strength in symptomatic female carriers of Duchenne muscular dystrophy

Abstract

Duchenne muscular dystrophy (DMD) usually affects men. However, women are also affected in rare instances. Approximately 8% of female DMD carriers have muscle weakness and cardiomyopathy. The early identification of functional and motor impairments can support clinical decision making. Objective: To investigate the motor and functional impairments of 10 female patients with dystrophinopathy diagnosed with clinical, pathological, genetic and immunohistochemical studies. Methods: A descriptive study of a sample of symptomatic female carriers of DMD mutations. The studied variables were muscular strength and functional performance. Results: The prevalence was 10/118 (8.4%) symptomatic female carriers. Deletions were found in seven patients. The age of onset of symptoms in female carriers of DMD was quite variable. Pseudohypertrophy of calf muscles, muscular weakness, compensatory movements and longer timed performance on functional tasks were observed in most of the cases. Differently from males with DMD, seven female patients showed asymmetrical muscular weakness. The asymmetric presentation of muscle weakness was frequent and affected posture and functionality in some cases. The functional performance presents greater number of compensatory movements. Time of execution of activities was not a good biomarker of functionality for this population, because it does not change in the same proportion as the number of movement compensations. Conclusion: Clinical manifestation of asymmetrical muscle weakness and compensatory movements, or both can be found in female carriers of DMD mutations, which can adversely affect posture and functional performance of these patients.

Perspectives on Everyday Life Challenges of Danish Young People With Duchenne Muscular Dystrophy (DMD) on Corticosteroids

“…The representative credibility in this study can be argued to be uncertain due to the small sample of persons with DMD. Only boys were included in the study, since the disease almost never occurs in girls, and no girls with the diagnosis were registered at National Rehabilitation Center for Neuromuscular Diseases (Silva et al, 2020). Nevertheless, our sample even though small represented almost half of the persons with DMD in Denmark in the studied age group.…”

Identification of hub genes related to Duchenne muscular dystrophy by weighted gene co-expression network analysis

“…[ 14 ] Women are generally carriers, and may have mild cardiac dysfunction, but rarely have the disease. [ 15 , 16 ] The pathological degree of DMD is generally related to the decrease of muscle function and the deficiency of dystrophin on the plasma membrane of muscle fiber. However, these characteristics do not fully explain the formation of DMD muscle injury, which changes were not reported until the onset of the apparent disease.…”

Symptomatic female carriers of mutations in the Duchenne muscular dystrophy gene

“…In our two patients, we found duplication mutations by means of the MLPA method. Silva et al 1 found only one duplication, with deletions being the most common mutation in seven patients.…”

“…We read with interest the article published by Silva et al 1 on functional performance and muscular strength in symptomatic female carriers of the Duchenne muscular dystrophy (DMD) gene. If a female individual carries the dystrophin gene mutation on one of the two chromosomes, the second X-chromosome 'protects' her due to the production of a regular dystrophin protein.…”