|Principal Investigator: NicholasJohnson|
|Keywords: myotonic dystrophy , congenital myotonic dystrophy , CDM , dystrophia myotonia||Department: Neurology|
|IRB Number: 00066988||Co Investigator: AmyPowell|
|Sub Specialties: Muscular Dystrophy|
We propose to longitudinally characterize the symptoms and functional outcomes associated with CDM disease progression in early and late childhood to develop a model for symptom development and progression. This study will enroll sixty children with CDM and 30 control subjects with stratified recruitment into four cohorts (birth to 2 years, 11 months; 3 years to 5 years, 11 months; 6 years to 8 years, 11 months; and 9 years to 13 years, 11 months) in order to address the following Specific Aims.
To determine in a prospective manner important clinical endpoints for children with CDM and establish reliability, validity, and responsiveness of these endpoints at differing stages of the disease. These endpoints include medical morbidity and mortality, neuropsychological function, oral facial weakness, muscle weakness, respiratory function, gastrointestinal function, and cardiac conduction. These endpoints will be evaluated for feasibility, test-retest reliability, and responsiveness to change. Determining these profiles will provide accurate and impactful endpoints that may be extended to therapeutic trials.
To validate the disease specific, patient reported outcome measure developed for CDM by assessing its correlation with generic quality of life measures and functional outcome measures using the cross sectional and longitudinal data obtained in Aim 1. This validation process will assess the test-retest reliability, responsiveness of the patient-reported outcome measure-to-measure change, and the validity of the measurement compared to functional outcome measures and generic quality of life scores. In addition, analysis of the patient and parent proxy instruments completed by both parents and educators will assess the ability of various proxies to measure symptom impact and concordance between the proxy and patient instruments. At the completion of this Aim we will have a reliable, valid, and responsive patient reported outcome measure capable of measuring the aggregate symptom impact in this multi-system disease.
To evaluate potential biomarkers, including RNA splicing ratios, PGE2 levels, and lean muscle mass. Prior RNA splicing biomarkers may not be practical in young children. We will assess the ability to obtain accurate RNA splicing ratios and microRNA differences in blood samples. We will extend prior work evaluating a potential difference in PGE2 levels in CDM samples by assessing in vivo PGE2 levels in blood and urine. Lean body mass, as measured by DEXA, will be determined in a subset of children able to cooperate with this procedure. This imaging modality, which has been used commonly in other pediatric NM conditions, may be an important imaging biomarker reflecting muscle mass and may be responsive to change over time and change due to intervention.
Identify changes in functional connectivity in CDM participants’ brains when compared to age-matched controls using resting state fMRI. Resting state fMRI (R-fMRI) will be used to map the functional organization of the CDM brains of 20 children, age 7 or older. These scans will be compared to a set of age-matched controls to examine if brain activity is altered as a result of neurological disease. We hypothesize that the CDM brain will show functional differences at baseline.
Identify changes in functional connectivity in CDM participants’ brains over time. R-fMRI will be conducted on the same group of CDM children at one year from baseline to determine if there are changes in functional connectivity and organization over time, and how these changes are related to age and CDM.
Evaluate associations of identified functional changes in the CDM brain with clinical characteristics. Clinical endpoints of cognition, executive functioning, repetitive behaviors, social behaviors, and adaptive functioning that have been obtained annually as part of a disease progression study of which the CDM children are participants will be correlated with R-fMRI data to connect the underlying pathophysiology with the clinical phenotype.
Characteristics of subject population: Both male and female subjects will be recruited. Volunteers from diverse and racial backgrounds will be solicited through the use of local and national recruitment tools.
This study proposes a longitudinal study of 60 children with CDM stratified into the following age cohorts: birth to 2 years, 11 months; 3 years to 5 years, 11 months; 6 years to 8 years, 11 months; and 9 years to 13 years, 11 months. Enrollment will be evenly distributed between cohorts. In addition, 30 control subjects will be recruited,10 subjects per cohorts 2-4.
Inclusion criteria CDM group:
a. Age 0-13 years, 11 months of age
b. A diagnosis of CDM, which is defined as children having symptoms of myotonic dystrophy in the newborn period (<30 days), such as hypotonia, feeding or respiratory difficulty, requiring hospitalization to a ward or to the neonatal intensive care unit for more than 72 hours; and a genetic tests confirming an expanded trinucleotide (CTG) repeat in the DMPK gene in the child or mother. An expanded CTG repeat size in the child is considered greater than 200 repeats or E1–E4 classification (E1= 200–500, E2=500–1,000, E3=1,000–1,500, E4>1,500).
Inclusion criteria, controls:
a. Age 0-13 years, 11 months years of age
b. Healthy children on no medication
Exclusion criteria CDM group:
- Any other non-DM1 illness that would interfere with the ability or results of the study in the opinion of the site investigator
- Significant trauma within one month
- Internal metal or devices (exclusion for MRI and DEXA component)
- Any of the following, which impair the ability to measure PGE2 levels: Prolonged or recent NSAID use within one week; Treatment with glucocorticoids within one month; Vitamin B supplementation within one month; Coffee consumption within 2 days; Treatment with propafol (a general anesthetic) within one week; Chemotherapeutic or antineoplastic drugs (need a reference) within 3 months; Honokiol within one month; Diacerin/rhein within one month; Ethanol within one week; Silibinin/silimaryn within one month
Exclusion criteria, controls:
- Any illness or social situation that, in the opinion of the site investigator, has the possibility to interfere with study procedures
- Recent febrile illness within 2 weeks
- Hemolytic disease
- Increased levels of uric acid
- Idiopathic hypercalcuria – by history only
- Cystic Fibrosis
- DM types 1 and 2
- Active or remitted Hodgkin’s Disease (HD)
- Any of the items previously identified in item d of the exclusion criteria in the CDM subjects.