Long-term Effects of Annual Intensive Rehabilitation in Patients with Hereditary Pure Cerebellar Ataxia: A 7-year Follow-up Study

Background : Although intensive rehabilitation has achieved short-term benefits in patients with spinocerebellar degeneration, long-term outcomes of periodic intervention remain unclear, particularly in patients with pure spinocerebellar ataxia types 6 (SCA6) and 31 (SCA31). Objective : To investigate the longitudinal effects of annual intensive rehabilitation on ataxic symptoms and balance function in patients with pure cerebellar type SCA6 and SCA31. Methods : Seven patients with genetically confirmed SCA6 or SCA31 participated in annual 4-week intensive rehabilitation programs. Each program consisted of daily physical therapy, occupational/speech therapy, and self-directed balance training. The participants were assessed annually at pre-intervention, post-intervention, and the 6-month follow-up using the Scale for the Assessment and Rating of Ataxia (SARA) and Balance Evaluation Systems Test (BESTest). Changes were analyzed using linear mixed-effect models. Results : SARA scores were stable, indicating slower progression than the expected natural history, through year 6, with significant improvement observed post-intervention in year 2 (p=0.04). Significant deterioration occurred at year 7 based on pre-intervention scores (p=0.01), suggesting prolonged sustained benefits for coordination. The BESTest scores revealed an earlier decline, with significant deterioration from year 3 (p=0.04), which progressed until year 7 (p<0.01). Conclusions : Annual intensive rehabilitation demonstrated potential long-term benefits on motor functions in patients with pure cerebellar-type ataxia. Coordination function improved, suggesting prolonged slowing of progression. However, maintaining balance function may be more challenging under an annual intervention schedule. More frequent or comprehensive approaches, specifically targeting balance, may be necessary to complement the observed benefits in coordination and address the progressive decline in balance function.