COGNITIVE FUNCTION IN EARLY CLINICAL PHASE HUNTINGTON DISEASE AFTER RIVASTIGMINE TREATMENT
AbstractBackground: In Huntington disease (HD) patients receiving rivastigmine treatment improvement of behavioral symptoms and of
cognitive function (assessed with screening diagnostic instruments) has been reported. The aim of the present study was to verify
such improvement in cognitive function by cognitive function assessment with a detailed neuropsychological battery covering all
relevant cognitive systems expected to be impaired in early phase HD.
Subjects and methods: Eighteen (18) HD patients entered the study and were randomly allocated to the rivastigmine and
placebo group. All subjects underwent neuropsychological assessment at baseline. Follow-up neuropsychological assessment was
applied after 6 months of rivastigmine or placebo treatment. Eighteen (18) healthy controls entered the study to control for practice
effect and underwent neuropsychological assessment at baseline and after 6 months, without treatment. The neuropsychological
battery consisted of assessment tools that are sensitive to cognitive impairment seen in early phase HD: CTMT, SDMT, Stroop
(attention and information control), RFFT, TOL, Verbal fluency (executive functioning), CVLT-II, RCFT (learning and memory).
Effect of rivastigmine and possible effect of practice was assessed using the mixed ANOVA model.
Results: No statistically significant effect of rivastigmine treatment on cognitive function in HD patients was detected. There was
no evidence for practice or placebo effect.
Conclusions: Detailed neuropsychological assessment did not confirm previously reported effect of rivastigmine treatment on
cognitive function in HD patients. The limitations of our study are, in particular, small sample size and the lack of a single measure
of relevant cognitive functioning in HD patients. Instead of focusing solely on statistical significance, a clinical relevance study is
proposed to clarify the issue of rivastigmine effects in HD