Cerebellar cognitive-affective syndrome in Friedreich Ataxia.

BACKGROUND

Increasing evidence suggests that cognition and affect may be affected in Friedreich Ataxia (FA).

OBJECTIVES

To investigate the Cerebellar Cognitive Affective Syndrome (CCAS) in patients with FA and evaluate its correlations with speech and clinical parameters.

METHODS

Patients were recruited from the PROFA study (NCT05943002), a prospective observational cohort in France, Germany, and Austria. Assessments included clinical scales (Friedreich Ataxia Rating Scale-Activities of Daily Living, FARS-ADL, Scale for the Assessment and Rating of Ataxia), the CCAS scale, and patient-reported outcomes. Controls data were obtained from the READISCA study (NCT03487367).

RESULTS

A total of 101 patients with FA and 43 controls with similar ages were included (35.4 ± 14.9 years vs 38.8 ± 9.5 years, p = 0.11). The mean CCAS total raw score was lower in patients than in controls (92.4 ± 13.7 vs 104.0 ± 8.5, p < 0.001), with a higher rate of definite CCAS (47% vs 12%, p < 0.001). The most frequently impaired cognitive functions in FA were phonemic fluency (44% vs 14%, p < 0.001), categoric switching (41% vs 9%, p < 0.001), and semantic fluency (20% vs 2%, p = 0.007). In multivariate models, CCAS total raw score increased with higher education and decreased with FARS-ADL (both p < 0.001). Dysarthria had no significant effect on total or item-level CCAS scores after adjustment for education, FARS-ADL, mean GAA repeats, and study center (all p > 0.15).

DISCUSSION: Definite CCAS is common in FA, with deficits in phonemic fluency, categoric switching, and semantic fluency. Cognitive impairment appears independent of dysarthria severity, suggesting CCAS is an intrinsic manifestation of the disease.