Epidemiological, clinical, and functional profile of patients with amyotrophic lateral sclerosis in a reference center in Salvador, Bahia

Abstract

Background: Amyotrophic lateral sclerosis is a progressive neurodegenerative disease with high morbidity and mortality, characterized by marked clinical heterogeneity and frequent diagnostic delay. In Brazil, there is a scarcity of data on patient profiles, particularly in centers in the Northeast region. Objective: To characterize the epidemiological, clinical, and functional profile of patients with ALS treated at a reference center for rare diseases in Salvador. Methods: This observational, descriptive, retrospective study was based on a review of medical records of patients followed between January 2018 and December 2025 in a specialized neuromuscular outpatient clinic. This was a non-probabilistic convenience sample, including patients with a confirmed diagnosis of ALS and complete medical records, while excluding inconclusive cases and those with unresolved differential diagnoses. Results: The sample (n=67) showed a balanced sex distribution and a median age of 58 years (IQR: 46–66). Most patients had completed secondary education (n=25; 37.1%). There was a higher frequency of mixed-race individuals (n=25; 37.3%), and most patients were from the Metropolitan Region of Salvador (n=46; 68.7%). Clinically, the spinal-onset form predominated (n=47; 70.1%), as well as sporadic cases (n=66; 98.5%). The median time from symptom onset to diagnosis was 20 months (IQR: 10–35). Disease-modifying therapy was used by 76.1% of participants, all receiving riluzole, with a median time to treatment initiation of 2 years (IQR: 1–4), and 9.0% (n=6) discontinued treatment during follow-up. In addition to pharmacological management, care was primarily based on motor (n=36; 53.7%) and respiratory (n=30; 44.8%) physiotherapy, with limited multidisciplinary involvement [speech therapy (n=15; 22.4%), nutrition (n=11; 16.4%), psychology (n=4; 6%)], and 10.5% (n=7) received no treatment. Noninvasive ventilation (NIV) was used in 59.7% (n=40), bag-valve-mask devices in 53.7% (n=36), gastrostomy in 67.2% (n=45), and tracheostomy in 9.0% (n=6). Functionally, 47.8% (n=32) had significant dependence (wheelchair-bound or bedridden), while only 22.4% (n=15) retained preserved ambulation. Predicted forced vital capacity (FVC) had a median of 53% (IQR: 31–70). The mortality rate was 34.3% (n=23). Conclusion: This study provides a comprehensive characterization of the profile of ALS patients at a reference center in Salvador, highlighting predominance of sporadic, spinal-onset disease with high functional impairment and mortality. The prolonged median time to diagnosis and delayed initiation of disease-modifying therapy underscore difficulties in early recognition and timely management. Care was largely centered on pharmacological therapy and motor and respiratory physiotherapy, with limited multidisciplinary adhesion. These findings emphasize the need for earlier diagnosis, expansion of multidisciplinary care, and optimization of therapeutic strategies to improve clinical outcomes and quality of life.