Background In a rare disorder such as Huntington’s disease (HD) a global network of clinical trial sites with access to patients speeds up recruitment into clinical trials.
Aims To test the hypothesis that demographics, HTT genotype, clinical spectrum and progression are similar in HD participants of two large observational HD studies, the European Huntington’s Disease Network’s European REGISTRY study and the North American COHORT study.
Methods REGISTRY cross-sectional data were available from a total of 7,398 participants (1,125 (15.2%) premanifest, 6,273 (84.8%) manifest HD). COHORT cross-sectional data from 1,499 participants at 44 study sites were available (175 pre-HD (11.7%), 1,324 manifest HD (88.3%)). Participants were assessed clinically using the Unified Huntington’s Disease Rating Scale (UHDRS). Longitudinal data was available for total motor score or cognitive performance in more than 50% of REGISTRY participants and more than 70% of COHORT participants.
Results Demographics, HTT genotypes, phenotype and progression, were similar in the two studies. Patients in Europe were prescribed anti-dyskinetics more frequently, and anti-depressants less frequently, than in North America. In either study, participants on anti-dyskinetic medication had higher UHDRS total motor scores, worse function assessment scores and worse cognitive scores than those taking anti-depressants or no medication. In contrast, motor, function assessment and cognitive scores were broadly similar in participants taking anti-depressants or no medication. The differences in cognitive performances between languages were small.
Conclusions Our data suggest that HD patients, and the way they are assessed, are similar across two continents with different cultures and languages.
- clinical trials
- observational cohort study
- rare disease
- global recruitment