Poster 18: Lack of Awareness of Motor and Cognitive Phenoconversion in Huntington's Disease

Abstract

Background Self-awareness of Huntington's disease (HD) onset has rarely been studied in a premanifest cohort, but poor recognition and reporting of symptoms could lead to a delay in diagnosis and, with that, appropriate management/care and notification of family regarding their HD risk. Moreover, poor awareness of first onset of HD could result in collecting inaccurate information about the disease; treatment, if available, could be delayed; and reports of drug effectiveness, inaccurate. Also, some patients, once they have undergone testing for the HD mutation, become overly “aware” of possible symptoms. We investigated this in a cross-sectional sample of 615 participants attending their third visit in the Predict-HD study. Results Of these, 79 (13%) were recently diagnosed with manifest HD. However, more than a third of those diagnosed did not acknowledge any disease symptoms, despite showing similar signs of decline in terms of UHDRS Motor and TFC scores, psychomotor performance (Tapper), and companion ratings of frontal/executive dysfunction. Participants who reported not noticing any symptoms of HD also reported significantly less depression and fewer behavioral difficulties (indicative of frontal/executive dysfunction), consistent with poor insight. For participants who were classified as premanifest, those reporting symptoms of HD tended to have more cognitive, psychiatric, and other symptoms (compared to motor symptoms, which were most common in the recently diagnosed group). In the premanifest group, participants reporting symptoms had significantly higher ratings of depression and frontal/executive dysfunction (compared to those who were ‘symptom-fee'), rating themselves similarly to the group with HD diagnosis, despite fewer signs of disease (i.e., better Motor, TFC, and Tapper scores) and longer estimated time to disease onset. Conclusions These results suggest that poor awareness of HD is a substantial problem in the premanifest or early stages of HD, but further research is needed to examine the predictors and implications of under/over reporting of HD symptomatology.