Ataxia is common in various forms of human prion diseases but there is a dearth of validated assessment tools and data on the subject. Originally used for inherited cerebellar ataxias, the Scale for Assessment and Rating of cerebellar Ataxia (SARA) and Composite Cerebellar Functional Severity Score (CCFS) have been incorporated into the National Prion Monitoring Cohort (NPMC) as semi-quantitative measures of posture, gait, kinetic dysfunction and speech in patients with sporadic and inherited Creutzfeldt-Jakob disease (CJD).
SARA and CCFS assessments were completed for patients with sporadic CJD (sCJD, n=119), and inherited prion disease (IPD, n=46). Patients were concurrently scored on the Medical Research Council Prion Disease Rating Scale (MRC PDRS), a functionally-oriented measure of disease progression validated in CJD patients.
SARA scores in sCJD and IPD patients showed a strong, statistically significant correlation with the MRC PDRS. The SARA score may be useful in providing semi-quantitative evidence of deteriorating co-ordination in sCJD and IPD patients; serial attainment of scores could represent an objective measure of response to clinical therapeutic trials in CJD.