However, the whole group of heterozygous and homozygous normal at-risk individuals showed a significantly greater number of psychiatric episodes than did their 43 spouses, suggesting stress from the uncertainty associated with belonging to a family segregating this disorder. (1995) performed extensive neuropsychologic evaluations on 8 genotype-positive individuals comparing them to 8 genotype-negative individuals from families with Huntington disease.They found no significant differences between these 2 groups, casting further doubt on earlier reports that suggested cognitive impairments are premonitory signs of the classical neurologic syndrome of Huntington disease. (1995) performed a double-blind study on 33 persons at risk for HD who had applied for genetic testing.Significantly inferior cognitive functioning was disclosed in gene carriers by a battery of neuropsychologic tests covering attentional, visuospatial, learning, memory, and planning functions.Primarily, attentional, learning, and planning functions were affected. (1995) performed a prospective analysis of neuropsychologic performance and CT scans of 60 individuals with Huntington disease.For example, gene carriers lost to follow-up, those deceased before onset of disease, and those who had not yet manifested the disease at the time of data collection were excluded from the observed distribution of age at onset.
The frequency of symptomatic schizophrenia was 9%, and significant personality change was found in 72% of the sample.
The mutation carriers without symptoms had higher scores for anxiety, paranoid ideation, and psychoticism compared to the nonmutation control group.
The results indicated that individuals in the preclinical stage of HD exhibit specific psychiatric symptoms and that additional symptoms may manifest later in the disease course.
A characteristic atrophy of the caudate nucleus is seen radiographically.
Typically, there is a prodromal phase of mild psychotic and behavioral symptoms which precedes frank chorea by up to 10 years.