Clinical Characterization of Patients With <scp>5q</scp> Spinal Muscular Atrophy Types 2 and 3 in Brazil: A Cross‐Sectional Observational Study
Spinal muscular atrophy (SMA), linked to chromosome 5q, is a rare hereditary neurodegenerative disease characterized by progressive motor neuron loss. It is classified into subtypes based on age at onset and the highest motor milestone achieved. This cross-sectional observational study aimed to describe the clinical profile of patients with types 2 and 3 SMA followed within the Brazilian Public Health System (SUS). Clinical data from patients with types 2 and 3 SMA followed at nine national reference centers (2020-2021) were analyzed. A total of 155 patients were included: 76 with type 2 and 79 with type 3 SMA. Disease duration was longer in type 3 patients. Time from symptom onset to genetic confirmation was also longer in this group. Functional impairment was observed in both subtypes. Type 2 patients had lower HFMSE scores overall, though higher scores were seen among those on disease-modifying therapies. In type 3, earlier symptom onset and longer disease duration were associated with worse motor outcomes. HFMSE scores varied with treatment use and disease duration. Findings reveal the clinical heterogeneity of SMA and emphasize the impact of diagnostic delays and disease duration on function. Early diagnosis and ongoing multidisciplinary care are crucial.
Authors
- Graziela Jorge Polido (ORCID: https://orcid.org/0000-0002-8748-8509)
- Ronaldo V P Soares (ORCID: https://orcid.org/0009-0004-4817-3899)
- Gisele Sampaio Silva (ORCID: https://orcid.org/0000-0002-3247-3123)
- Paulo Victor Sgobbi de Souza (ORCID: https://orcid.org/0000-0002-7416-7108)
- Raquel Tavares Boy da Silva (ORCID: https://orcid.org/0000-0001-6432-4870)
- André Luíz Santos Pessoa
- Jomênica de Bortoli Livramento
- Denison Pedrosa (ORCID: https://orcid.org/0000-0003-2947-0842)
- Frederico Monfardini (ORCID: https://orcid.org/0000-0002-9590-5448)
- Viviane Aparecida Rodrigues Sant’Anna (ORCID: https://orcid.org/0000-0002-5008-3129)
- Pereira Mde B
- Luciana Pereira Almeida de Piano (ORCID: https://orcid.org/0009-0008-2868-1019)
- Luiz Vicente Rizzo (ORCID: https://orcid.org/0000-0001-9949-9849)
- Jonas Alex Morales Saute (ORCID: https://orcid.org/0000-0003-1141-6573)
- Alexandra Prufer de Queiroz Campos Araújo (ORCID: https://orcid.org/0000-0003-2591-4354)
- Adriana Banzzatto Ortega
- Elice C. Batista
- Bruna dos Santos Sampaio
- Camila Santos Nascimento Albuquerque
- Flávia Duarte
- Gustavo Prado dos Santos
- Juliana Gurgel Giannetti
- O Berwanger
- Acary Souza Bulle Oliveira (ORCID: https://orcid.org/0000-0002-6986-4937)
- Vanessa Teich
- Marcondes Cavalcante França Junior (ORCID: https://orcid.org/0000-0003-0898-2419)
- Diogo Fagundes Moia
- João Brainer Clares de Andrade (ORCID: https://orcid.org/0000-0001-8768-7164)
- Henrique Andrade R. Fonseca
- Mário Fritsch Toros Neves
- Fernando Galan Júnior
- Edmar Zanoteli (ORCID: https://orcid.org/0000-0002-4991-6760)
Institutions
- Universidade Federal de Minas Gerais (BR)
- Universidade Federal do Rio de Janeiro (BR)
- Universidade Federal do Rio Grande do Sul (BR)
- Universidade de São Paulo (BR)
- Universidade Estadual de Campinas (UNICAMP) (BR)
- The George Institute for Global Health (GB)
- Hospital Israelita Albert Einstein (BR)
- Hospital de Clínicas de Porto Alegre (BR)
- Hospital Universitário Pedro Ernesto (BR)
- Hospital Erasto Gaertner (BR)
- Hospital Infantil Albert Sabin (BR)
- Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (BR)
- Imperial College London (GB)
- Universidade Federal do Estado do Rio de Janeiro (BR)
- Universidade Federal de São Paulo (BR)
Publication Details
- Journal
- Clinical Genetics
- Published
- 2026-05-08
- DOI
- https://doi.org/10.1111/cge.70176
- Primary Topic
- Neurogenetic and Muscular Disorders Research
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Ministério da Saúde