Awareness screening and referral patterns among pediatricians in the United States related to early clinical features of spinal muscular atrophy (SMA)

Abstract

Background: Spinal Muscular Atrophy (SMA), a leading genetic cause of death in infants, is an autosomal recessive neuromuscular disease characterized by progressive muscle weakness and atrophy. While early diagnosis of SMA is critical to modifying disease progression and improving outcomes, serious diagnostic delays persist. There is a need to improve SMA awareness, screening, and referral patterns.

Methods: Two online surveys, developed by Cure SMA for general pediatricians, were distributed by Medscape Education via email (September 2018, n = 300, December 2019, n = 600). The surveys asked about adherence to the American Academy of Pediatrics (AAP) developmental screening and surveillance guidelines, comfort with identification of early signs of neuromuscular disease (NMD), familiarity with SMA, and barriers to timely referral.

Results: In 2018, 70.3% of survey respondents indicated comfort in identifying early signs of NMD and 67.3% noted familiarity with SMA. 52.7% correctly indicated the need for genetic testing to make a definitive diagnosis of SMA, 74.0% meet or exceed developmental screening recommendations, and 52.0% said they would immediately refer to a specialist. In 2019, with a larger sample, 73.0% adhere to developmental screening guidelines, and awareness of the genetic testing requirement for SMA was significantly lower by 7.7% (p < 0.03). Specialist wait times emerged as a barrier to referral, with 64.2% of respondents citing wait times of 1-6 months.

Conclusions: Many pediatricians underutilize developmental screening tools and lack familiarity with diagnostic requirements for SMA. Continuing efforts to expand awareness and remove barriers to timely referral to SMA specialists, including reducing appointment wait times, are needed.

Fig. 1

Providers’ Response Upon Observation of Hypotonia by Self-Reported Comfort Identifying Neuromuscular Disease (2018 Survey). The breakdown of self-reported comfort identifying the early signs of NMD is as follows: Extremely comfortable: 3.3% (n = 10); Very comfortable: 18.7% (n = 56); Moderately comfortable: 48.3% (n = 145); Slightly Comfortable: 26.7% (n = 80); Not at All Comfortable: 3.0% (n = 9). The breakdown of provider response upon observation of hypotonia in an infant or toddler* is as follows: Immediate referral to pediatric neurologist for further evaluation: 52.0% (n = 156); Immediate referral to early intervention for further evaluation: 55.3% (n = 166); Wait and see, evaluate at next scheduled well visit: 14.0% (n = 42).* Each pediatrician had the option to ‘select all that apply’ for the provided responses

Fig. 2

Provider Awareness of SMA Diagnostic Requirements Organized by Self-Reported Familiarity with the Disease (2018 Survey). The breakdown of self-reported familiarity with SMA is as follows: Extremely familiar: 4.3% (n = 13); Very familiar: 13.7% (n = 41); Moderately familiar: 49.3% (n = 148); Slightly Familiar: 30.3% (n = 91); Not at All Familiar: 2.3% (n = 7). The breakdown of provider response regarding the testing required for SMA diagnosis is as follows: Electromyography: 11.3% (n = 34); Genetic testing: 52.7% (n = 158); MRI: 0.7% (n = 2); Muscle biopsy: 31.0% (n = 93); Serum creatine kinase: 4.3% (n = 13)

Fig. 3

Percent (%) of patients referred via each method across all practices (2019 Survey)

Fig. 4

Percent of patients referred to a neurologist / pediatric neurologist in previous 12 months (2019 Survey)

Fig. 5

Factors considered when choosing a neurologist / pediatric neurologist for receipt of patient referral (2019 Survey)

Fig. 6

Average wait time for first appointment to see neurologists / pediatric neurologists in respondents’ region (2019 Survey)

Fig. 7

Perceived Contributors to Average Wait Time for Patients Completing a Neurology/Pediatric Neurology Referral (2019 Survey)