Thinking outside the box: A re-evaluation of Canadian recommended outcome measures in adult spinal muscular atrophy – report of a national consensus workshop

Background Disease-modifying therapies for persons with spinal muscular atrophy (SMA) has led to greater need and demand for relevant outcomes assessments. Such tools help monitor disease progression, assess treatment response, and inform clinical management. Canadian SMA clinicians participated in a Delphi process to achieve a 2021 national consensus on recommended outcomes, recognizing future reassessment would be essential given the evolving field and gaps in patient-reported and bulbar measures. Objective Derive updated Canadian consensus of recommended outcome measures for adults with SMA. Methods A national consensus workshop was held with SMA clinicians, patient/family representatives, research leaders, national registry and advocacy organizations. Clinics and registry experience and data were presented and discussed, utility of current and additional outcomes reviewed. Long and short lists of measures were generated, with voting to derive consensus. Results Practical implementation, value of data, and relevance to persons with SMA were key considerations. Consensus was achieved to ‘think outside the box’, recognizing a spectrum of function and need to choose the right outcome measure for the right patient at the right time. Measures with greater acceptance for adults were selected, and bulbar measures introduced. Eight outcome measures are recommended; 4 motor, 2 respiratory and 2 patient reported domains, with use based on the individuals level of function. The Revised Upper Limb Module was deemed to have broadest applicability except in the strongest and weakest adults. Additional measures are included as optional and exploratory. Conclusions Employing measures meaningful for clinicians, researchers, and persons living with SMA is essential to ensuring quality data collection and an engaged patient-centred clinical team. Clinicians should select measures based on the person's functional ability and goals. Building a national community of practice to support clinical and research practice, including standardized outcome measure training, will be a key next step in dissemination and advocacy.