Consensus Statement for Standard of Care in Spinal Muscular Atrophy

Abstract

Spinal muscular atrophy is a neurodegenerative disease that requires multidisciplinary medical care. Recent progress in the understanding of molecular pathogenesis of spinal muscular atrophy and advances in medical technology have not been matched by similar developments in the care for spinal muscular atrophy patients. Variations in medical practice coupled with differences in family resources and values have resulted in variable clinical outcomes that are likely to compromise valid measure of treatment effects during clinical trials. The International Standard of Care Committee for Spinal Muscular Atrophy was formed in 2005, with a goal of establishing practice guidelines for clinical care of these patients. The 12 core committee members worked with more than 60 spinal muscular atrophy experts in the field through conference calls, e-mail communications, a Delphi survey, and 2 in-person meetings to achieve consensus on 5 care areas: diagnostic/new interventions, pulmonary, gastrointestinal/nutrition, orthopedics/rehabilitation, and palliative care. Consensus was achieved on several topics related to common medical problems in spinal muscular atrophy, diagnostic strategies, recommendations for assessment and monitoring, and therapeutic interventions in each care area. A consensus statement was drafted to address the 5 care areas according to 3 functional levels of the patients: nonsitter, sitter, and walker. The committee also identified several medical practices lacking consensus and warranting further investigation. It is the authors' intention that this document be used as a guideline, not as a practice standard for their care. A practice standard for spinal muscular atrophy is urgently needed to help with the multidisciplinary care of these patients.

New insights into SMA pathogenesis: immune dysfunction and neuroinflammation

“…Accordingly, many SMA patients had nonmucocutaneous candidiasis, which usually only occurs in immunodeficient individuals 25. Moreover, pulmonary infection, especially pneumonia, appears to be a common feature of SMA patients 26, 27, 28, 29, 30. Decreased respiratory efficiency and stasis of secretions can increase risk of infections 29, 31.…”

Parental attitudes toward newborn screening for Duchenne/Becker muscular dystrophy and spinal muscular atrophy

“…Although the diaphragm is spared in SMA, expiratory and intercostal muscles are weakened, making breathing difficult (D'Amico, 2011). This leads to recurrent chest infections, decreased respiratory function, impaired cough with poor secretion clearance, and eventually respiratory failure (Wang, 2007;D'Amico, 2011). …”

“…SMA should be on the list of differential diagnoses when a severely weak child or hypotonic baby presents with normal attentiveness and cognitive function (Menezes, 2011;D'Amico, 2011). SMA-related weakness is typically proximal and symmetrical, and tendon reflexes are diminished or absent (Wang, 2007;D'Amico, 2011). There are no associated sensory abnormalities (Wang, 2007).…”

“…SMA-related weakness is typically proximal and symmetrical, and tendon reflexes are diminished or absent (Wang, 2007;D'Amico, 2011). There are no associated sensory abnormalities (Wang, 2007). In SMA type I, there may be feeding difficulties, a weak cry and cough, and impaired head control (D'Amico, 2011).…”

Baseline results of the NeuroNEXT spinal muscular atrophy infant biomarker study

“…15, 16 Natural history studies in the SMA type 1 population demonstrated shortened lifespan, with 68% mortality within the first 2 years of life 9, 10. With the advent of standardized care guidelines,17 the mortality of SMA type 1 infants has been reduced at 2 years of age to 30%, with nearly half of these infants dependent upon noninvasive ventilation 18. In a recent observational study, SMA infants who developed symptoms prior to 6 months of age demonstrated very poor motor function and significant motor loss electrophysiologically at the enrollment visit 19.…”