Longitudinal changes in clinical outcome measures in COL6-related dystrophies and LAMA2-related dystrophies

Minal S Jain1, Katherine Meilleur2, Eunhee Kim2

  • 1From the Rehabilitation Medicine Department (M.S.J., M.W., R.V., R.L., C.N.), Clinical Research Center, Neuromuscular Symptoms Unit (K.M., I.C., M.L., M.P., J.E., F.T., J.W.), Tissue Injury Branch, National Institute of Nursing Research, Clinical Trials Unit (E.K., G.N.) and Neuromuscular and Neurogenetic Disorders of Childhood Section (S.D., M.L., E.H., G.M.A., A.K., A.S., K.Z., P.M., D.B.-G., A.R.F., C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, and Pulmonary Branch (M.B., J.F., P.M.), National Heart, Lung, and Blood Institute, NIH, Bethesda, MD; Departments of Physical Therapy (L.N.) and Clinical Sciences (L.H.), University of Texas Southwestern, Dallas; Occupational Therapy and Physical Therapy Department (M. McGuire, J.C.C.), Cincinnati Children's Hospital Medical Center, OH; Pediatric Rehabilitation Medicine Department (T.D.), Children's National Medical Center, Washington, DC; Physical Therapy Department (K.K.), Rady's Children Hospital, San Diego, CA; Department of Physical Therapy (D.J.L.), University of Florida, Gainesville; Physical Therapy Department (A.G.), Children's Hospital of Philadelphia, PA; Paediatric Gait Analysis Laboratory of New South Wales (K.R.), The Children's Hospital at Westmead, Sydney, Australia; Dubowitz Neuromuscular Centre (M. Main), Great Ormond Street Hospital for Children, London, UK; Department of Physical Therapy (C.F.), Kennedy Krieger Institute, Baltimore, MD; G.H. Sergievsky Center and Department of Neurology (R.F., V.H.), Columbia University, New York, NY; Goryeb Children's Hospital (J.D.), Morristown, NJ; CureCMD (E.S.K., A.R.), Torrance, CA; and L'Escale Service Central de MPR pédiatrique (C.V.), Hospices Civils de Lyon, France carsten.bonnemann@nih.gov mjain@cc.nih.gov.

Neurology
|October 27, 2019
PubMed

Insights

Congenital muscular dystrophies (CMD) like COL6-RDs and LAMA2-RDs cause significant yearly declines in motor function, muscle strength, and pulmonary function in children. Quality of life did not significantly change over the 4-year study period.

Area of Science:

  • Neurology
  • Pediatrics
  • Genetics

Background:

  • Congenital muscular dystrophies (CMD) are a group of inherited muscle disorders affecting children.
  • COL6-related dystrophies (COL6-RDs) and LAMA2-related dystrophies (LAMA2-RDs) are distinct subtypes with varying clinical presentations.
  • Understanding the rate of disease progression is crucial for managing these conditions.

Purpose of the Study:

  • To determine the annual rate of change in clinical outcome measures for children diagnosed with COL6-RDs and LAMA2-RDs.
  • To compare the progression rates between these two types of congenital muscular dystrophy.

Main Methods:

  • A longitudinal study followed 47 children (aged 4-22 years) with either COL6-RDs (n=23) or LAMA2-RDs (n=24) over 4 years.
  • Clinical assessments included the Motor Function Measure 32 (MFM32), myometry, goniometry, pulmonary function tests, and quality-of-life questionnaires.
  • Linear mixed-effects models were used to analyze the rate of change for each outcome measure.

Main Results:

  • Children with COL6-RDs and LAMA2-RDs showed significant yearly declines in total MFM32 scores (4.01 and 2.60 points, respectively).
  • Muscle strength decreased across most groups, with notable reductions in knee extension and elbow flexion/extension.
  • Range of motion decreased in specific joints, and pulmonary function (forced vital capacity) declined annually in COL6-RD patients.

Conclusions:

  • This study quantifies the progressive decline in motor function, muscle strength, and pulmonary capacity in children with COL6-RDs and LAMA2-RDs.
  • The findings highlight the significant impact of these conditions on physical function over time.
  • No significant changes were observed in quality-of-life measures during the study period.
Abstract