Author Response: Timing and Impact of Psychiatric, Cognitive, and Motor Abnormalities in Huntington Disease.

Abstract

We are grateful for the comments on our article.1 Typically, clinical onset of Huntington disease (HD) in HD gene carriers is diagnosed by expert clinicians using the emergence of extrapyramidal motor features, which are highly specific for HD. Although clinical onset is an artificial point on a continuous disease trajectory, patients can find the concept useful in developing life decisions around employment, finances, and medical care. Given that psychiatric and cognitive symptoms commonly predate motor problems in HD,1 Bird et al. suggest that these should play a diagnostic role in patients with a positive genetic test. We agree that specific neuropsychiatric symptoms in a HD gene carrier, such as sustained apathy or irritability/aggression, are strongly suggestive of HD pathology. Hallucinations and delusions may also occur, as suggested, but likely only constitute a small proportion of cases at this stage of the condition.