Background Various drugs are used in management of chorea in HD patients, but for most of them there is no evidence based medicine (EBM) data confirming the efficacy. In European HD centres first choice drugs for motor symptoms are usually tiapride, olanzapine, quetiapine and tetrabenazine.

Aims Aim of this study was to compare motor symptoms, including chorea and cognitive competence using Stroop interference test in HD patients on stable doses of tiapride, olanzapine and tetrabenazine lasting for one year.

Methods We analysed medications used as a first choice drugs in management of HD motor symptoms in patients from REGISTRY and Enroll-HD studies of two Polish Sites: Warsaw-IPiN and Poznan. Among 420 subjects (280 from Warsaw-IPiN and 140 from Poznan) we selected 63 patients, who started to be treated for HD motor symptoms during baseline visit (BL) and were on stable doses for one year until a follow-up visit (FUP).

Results Among the 63 patients tiapride was used as a first choice drug in 20 cases, tetrabenazine in 16 cases, olanzapine in 8 cases, quetiapine in 4 cases, haloperidol in 4 cases, sulpiride in 2 cases and Risperidone in 1 case. Statistical comparison of UHDRS parameters at BL and FUP were made for tiapride, tetrabenazine and olanzapine.

For tiapride comparing mean scores of baseline and follow up visits revealed not significant worsening in TMS score, respectively BL 36.9 ± 3.7, FUP 40.3 ± 4, (P > 0.05), for chorea subscore respectively BL 10.3 ± 1.1, FUP 10.89 ± 1.1 (P > 0.05) and for cognitive Stroop interference score respectively BL 24 ± 2.4, FUP 22 ± 6 (p > 0.05).

For tetrabenazine comparing mean scores of baseline and follow up visits revealed no change in TMS score, respectively: BL 45.2 ± 4.7, FUP 46.5 ± 4.7, (P > 0.05), for chorea subscore, respectively 12.1 ± 1.2, 10.5 ± 08, (P > 0.05). During FUP visit the mean cognitive interference score was significantly decreased, respectively: BL 23 ± 2.7, FUP 18.6 ± 2.5(p = 0.03).

For olanzapine no changes of mean TMS score at BL and FUP were found, respectively BL 46.2 ± 5.2, FUP 51 ± 6.5, (P > 0.05), chorea subscore, respectively BL 10.2 ± 1.4, FUP 9.5 ± 1.7 (P > 0.05) and cognitive interference score, respectively BL 20.1 ± 3.5 FUP 20.8 ± 2.8 (p > 0.05).

Conclusions Tiapride, tetrabenazine and olanzapine are the most often first choice drugs in management of chorea in Polish HD Study Sites: Poznan and Warsaw-IPiN, however their effectiveness in a year observation seems to be limited. This could be explained by HD progression and lack of neuroprotective effect of these drugs. Moreover, they may have (mostly tetrabenazine) a significant negative impact on cognitive abilities.