Can simple and low-cost motor function assessments help in the diagnostic suspicion of Duchenne muscular dystrophy? / Avaliações simples da função motora e de baixo custo podem ajudar na suspeita diagnóstica da distrofia muscular de Duchenne?

Abstract Objective: Duchenne muscular dystrophy, an X-linked genetic disease, leads to progressive muscle weakness mainly in the lower limbs. Motor function tests help to monitor disease progression. Can low-cost, simple assessments help in the diagnostic suspicion of Duchenne muscular dystrophy? The authors aim to define the sensitivity of time to rise from the floor, time to walk 10 meters, and time to run 10 meters, evaluating them as eventual diagnostic screening tools. Methods: This is an analytical, observational, retrospective (1998-2015), and prospective study (2015-2018). Cases were recruited from the database of the pediatric neurology department and the healthy, from child care consultations, with normal gait development (up to 15 months) and without other comorbidities (neuromuscular, pulmonary, heart diseases) from the same university hospital. Results: 128 Duchenne muscular dystrophy patients and 344 healthy children were analyzed, equally distributed in age groups. In Duchenne muscular dystrophy, there is a progressive increase in the means of the times to perform the motor tests according to the age group, which accelerates very abruptly after 7 years of age. Healthy children acquire maximum motor capacity at 6 years and stabilize their times. The time to rise showed a p-value <0.05 and a strong association (effect size [ES] >0.8) in all age groups (except at 12 years), with time to walk 10 meters from 9 years, and with time to run 10 meters , from 5 years. The 100% sensitivity points were defined as follows: time to rise, at 2 s; time to walk 10 meters, 5 s; time to run 10 meters, 4 s. Conclusions: Time to rise is a useful and simple tool in the screening of neuromuscular disorders such as Duchenne muscular dystrophy, a previously incurable disease with new perspectives for treatment.

Resumo Objetivo: A distrofia muscular de Duchenne, doença genética ligada ao X, determina fraqueza muscular progressiva principalmente em membros inferiores. Os testes de função motora ajudam a monitorar a progressão da doença. Avaliações simples de baixo custo podem ajudar na suspeita diagnóstica da distrofia muscular de Duchenne? Objetivamos definir a sensibilidade do tempo levantar, tempo andar 10 metros e tempo correr 10 metros, avaliando-os como eventuais ferramentas de triagem diagnóstica. Métodos: Estudo analítico, observacional, retrospectivo (1998 até 2015) e prospectivo (2015 até 2018). Os casos foram recrutados do banco de dados do serviço de neurologia infantil e os saudáveis, de consultas de puericultura, com desenvolvimento de marcha normal (até os 15 meses) e sem outras comorbidades (neuromusculares, pneumopatias, cardiopatias), do mesmo hospital universitário. Resultados: Foram analisados 128 pacientes com distrofia muscular de Duchenne e 344 saudáveis, distribuídos igualmente em faixas etárias. Na distrofia muscular de Duchenne ocorre aumento progressivo das médias dos tempos para realizar as provas motoras, de forma acentuada a partir dos 7 anos. Os saudáveis estabilizam os tempos a partir dos 6 anos, adquirindo capacidade motora máxima. O tempo de levantar apresentou p-valor <0,05 e forte associação (TE >0,8) em todas as faixas etárias (exceto aos 12 anos), tempo de andar 10 metros a partir de 9 anos e o tempo de correr 10 metros, dos 5 anos. Os pontos de 100% sensibilidade foram definidos: tempo de levantar aos 2 segundos; tempo de andar, 5 segundos e tempo de correr 10 metros, 4 segundos. Conclusões: O tempo de levantar é útil e simples na triagem de doenças neuromusculares como a distrofia muscular de Duchenne, doença antes incurável com novas perspectivas de tratamento.

Can simple and low-cost motor function assessments help in the diagnostic suspicion of Duchenne muscular dystrophy?

OBJECTIVE: Duchenne muscular dystrophy, an X-linked genetic disease, leads to progressive muscle weakness mainly in the lower limbs. Motor function tests help to monitor disease progression. Can low-cost, simple assessments help in the diagnostic suspicion of Duchenne muscular dystrophy? The authors aim to define the sensitivity of time to rise from the floor, time to walk 10meters, and time to run 10meters, evaluating them as eventual diagnostic screening tools. METHODS: This is an analytical, observational, retrospective (1998-2015), and prospective study (2015-2018). Cases were recruited from the database of the pediatric neurology department and the healthy, from child care consultations, with normal gait development (up to 15 months) and without other comorbidities (neuromuscular, pulmonary, heart diseases) from the same university hospital. RESULTS: 128 Duchenne muscular dystrophy patients and 344 healthy children were analyzed, equally distributed in age groups. In Duchenne muscular dystrophy, there is a progressive increase in the means of the times to perform the motor tests according to the age group, which accelerates very abruptly after 7 years of age. Healthy children acquire maximum motor capacity at 6 years and stabilize their times. The time to rise showed a p-value <0.05 and a strong association (effect size [ES] >0.8) in all age groups (except at 12 years), with time to walk 10 meters from 9 years, and with time to run 10 meters , from 5 years. The 100% sensitivity points were defined as follows: time to rise, at 2s; time to walk 10 meters, 5s; time to run 10 meters, 4s. CONCLUSIONS: Time to rise is a useful and simple tool in the screening of neuromuscular disorders such as Duchenne muscular dystrophy, a previously incurable disease with new perspectives for treatment.

Timed motor function tests capacity in healthy children.

OBJECTIVE: Motor function tests are used clinically and in research in children, particularly in those with neuromuscular disorders. Timed function tests are recommended in the follow-up of patients with neuromuscular disorders. This study was designed to know how healthy children perform on simple timed motor function tests. MATERIAL AND METHODS: In a cross-sectional observational study, 345 children aged 2-12 years, followed at the Federal University of Rio de Janeiro's Institute of Paediatric, were evaluated. To be eligible they had to have acquired independent walking before the age of 14 months, be able to cope and willing to participate in the study. Anthropometric and vital signs were verified, as well as contact with smokers. The following timed motor function tests were measured: time to rise from the floor (TRF), time to walk 10 meters (10MWT) and time to run 10 meters (10MRT). RESULTS: Improvement in time to perform those motor functions was found to occur in healthy preschool children. Stabilisation of mean times for those motor functions was seen thereafter: TRF of 1.2 s, 10MWT of 10 s and 10MRT of 5 s. CONCLUSIONS: Walking and rising speed improve with age in preschoolers, as expected, and is shown to occur up to a plateau level. Our findings for the 10MWT, 10MRT and TRF are in line with those published in 2008 for the 6 minute walk test (6MWT). The motor functions used in the present study require less time and space than the ones in the 6MWT. They should be considered more universally applicable. Those tests could be used in childcare clinics as a screening for motor disorders such as the neuromuscular diseases. TRIAL REGISTRATION NUMBER: 1.098.302.

Distrofia muscular de Duchenne: fatores da história associados ao diagnóstico precoce / Duchenne's muscular dystrophy: factors of the familiar history associated to early diagnosis

Objetivo: avaliar caracaterísticas da história dos pacientes com diagnóstico de Distrofia Muscular de Duchenne que chegam ao serviço de neuropediatria nos primeiros 5 anos de vida, comparando-as com os que chegam mais tardiamente, a fim de buscar explicações para a demora do diagnóstico. Métodos: pacientes com diagnóstico de DMD confirmado pela ausência de distrofia em imuno-histoquímica de biópsia muscular ou pesquisa de deleção do gene da distrofina foram divididos em dois grupo de acordo com a idade da primeira consulta no serviço de neuropediatria: até cinco anos de idade (13 casos) ou após (28 casos). Foram comparadas a idade de percepção dos sintomas pela família e a presença de história familiar, sendo calculada a razão de chances. Resultado: observou-se uma chance de 2,81 vezes maior da criança ter seu primeiro atendimento no serviço de referência antes dos cinco anos quando havia uma história familiar prévia (0,9