Therapeutic Management and Use of Resources and Costs of Spinal Muscular Atrophy in Spain

Sociodemographics included:

• Biological sex
• Dead patients
• Growth percentiles for growth charts (3%, 4-15%, 16-50%, 51-85%, 86-97%, greater than 97%)
• Patient's cohabitants (father, mother, both parents, brother(s), sister(s), other relatives)
• Patient's caregiver (father, mother, both parents, brother(s), sister(s), other relatives)
• Patient's primary caregiver (father, mother, both parents, brother(s), sister(s), other relatives)

• Age at the time of data collection
• Age of onset of SMA symptoms
• Age at clinical diagnosis of SMA
• Age of death

Clinical characteristics included:

• Anti-adeno-associated virus serotype 9 (AAV9) antibody titer test
• Neonatal screening for SMA together with other screening tests
• Prenatal or perinatal SMA diagnosis
• Ventilatory support
• Patient with scoliosis
• Patient with scoliosis surgery
• Patients with a chair for scoliosis
• Total or partial cost of the chair for scoliosis borne by the family
• Patients still use a chair for scoliosis at the time of data collection
• Patients with back brace
• Total or partial cost of the back brace borne by the family
• Patient with hip dislocations or subluxations
• Head control
• Relevant medical record
• End of ventilatory support

Time intervals included:

• Less than 1 month
• 1 to 3 months
• 4 to 6 months
• 7 to 18 months
• More than 18 months

ICD codes included:

• ICD-9 335.1: Spinal muscular atrophy
• ICD-9: 335.1: Spinal muscular amyotrophy, unspecified
• ICD-9 335.11: Kugelberg-Welander disease
• ICD-10 G12.1: Other hereditary spinal muscular atrophies
• ICD-10 G12.25: Progressive spinal muscular atrophy
• ICD-10 G12.8: Other spinal muscular atrophies and related syndromes
• ICD-10 G12.9: Spinal muscular atrophy, unspecified

Diagnosis types included:

• Clinical suspicion and subsequent patient referral for genetic confirmation
• Genetic diagnosis

Mutations included:

• Biallelic deletion of exons
• Biallelic deletion of exon 7
• Biallelic deletion of exons 7 and 8
• Compound heterozygous mutation
• Point mutation and deletion of exons 7 and 8
• Biallelic point mutation

SMN2 copy numbers: 0, 1, 2, 3, 4, and greater than 4.

SMA-associated comorbidities included:

• Chronic lung disease
• Swallowing impairment
• Malnutrition
• Hypoxic encephalopathy
• Relapsing obstructive bronchial syndrome
• Recurrent pneumonia
• Sleep apnea-hypopnea syndrome
• Epilepsy
• Hip dysplasia
• Obesity
• Respiratory compromise
• Thorax deformity
• Scoliosis
• Other

Family history categories included:

• Yes
• No
• Mother
• Father
• Both parents
• Brothers and sisters
• Other

Types of ventilatory support included:

• Invasive (hospital and outpatient)
• Non-invasive (hospital and outpatient)

Reasons of ventilatory support included:

• Preventive intent
• Therapeutic intent

Types of administration included:

• By mouth
• Through a feeding tube
• Both (mouth and feeding tube)
• Through gastrostomy

Types of nutritional supplementation included liquid thickeners (corn starch and Nutilis Clear thickener, neutral taste, Nutricia) and nutrition supplements (Resource shakes, High protein shakes, Ensure Junior drink, Infatrini, Pediasure Complete, RESOURCE C, Vitamin D, Fortini high protein shakes, protein shakes, Pediasure, Resource with fiber, Resource protein).

Types of surgeries included:

• Growing rods lengthening
• Dorsal/lumbar dorsal arthrodesis
• Growing rods

Types of joint contractures included proximal and distal.

Developmental Milestones:

• Sitting independently or with support
• Standing independently or with support
• Walking independently or with support
• Crawling with the elbows, belly crawl, or with hands and knees

Surgeries included:

• Mouth surgery
• Tracheostomy
• Surgery for gastrostomy
• Tenotomy
• Other

Healthcare visits included:

• General
• Primary care
• Pediatric neurology
• Rehabilitation physician
• Traumatologist
• Nutritionist
• Pulmonology
• Cardiologist
• Physical therapy
• Nursing staff
• Phoniatrist
• Speech therapist
• Rehabilitation sessions
• Other experts
• Emergency Room
• Related to therapy

SMA-related medical visits included:

• Primary care
• Pediatric neurology
• Rehabilitation physician
• Traumatologist
• Nutritionist
• Pulmonologist
• Cardiologist
• Physical therapist
• Nursing staff
• Phoniatrist
• Speech therapist
• Rehabilitation sessions
• Other specialists

SMA-related emergency room visits included outpatient and hospital visits.

SMA-related hospitalizations included visits to day hospital, admissions to ward, intensive care unit admissions.

Hospitalization included admission to ward. Reason for hospitalization included related to treatment and not related to treatment.

Reason for admission to ICU included related to treatment and not related to treatment.

Medical areas included:

• Pulmonology
• Endocrinology/nutrition
• Physical therapy
• Rehabilitation
• Logopedics
• Thoracic surgery
• Orthopedics
• Other

Additional tests included:

• Blood count
• Vitamin D test
• Blood creatine kinase test
• Electromyogram
• Brain magnetic resonance imaging
• Muscle magnetic resonance imaging
• Bone densitometry
• Nocturnal polysomnography
• Muscle biopsy
• Nerve conduction velocity study
• Blood amino acid test
• DNA test to confirm diagnosis

Additional tests included:

• Blood count
• Vitamin D
• Blood creatine kinase
• Electromyogram
• Brain magnetic resonance imaging
• Muscle magnetic resonance imaging
• Bone densitometry
• Nocturnal polysomnography
• Muscle biopsy
• Nerve conduction velocity study
• Blood amino acid test
• DNA test to confirm diagnosis

Treatments included:

• Nusinersen
• Risdiplam
• Onasemnogene abeparvovec
• Palivizumab
• Influenza vaccine
• Meningococcal vaccine
• High protein shakes

Nusinersen doses included loading and maintenance doses.

Risdiplam dose included starting dose and dose changes.