Psychiatric symptoms in neurologically asymptomatic Huntington's disease gene carriers: a comparison with gene negative at risk subjects

Abstract

Objective: Psychiatric profiles of two at-risk groups [Huntington's disease (HD) gene carriers and non-carriers] were compared by means of a computerized battery and a structured interview.

Method: To avoid confounding, only subjects who were free from neurological and cognitive deficits (neurologically asymptomatic) were included in the study. To avoid evaluation biases, all subjects were seen before the genetic testing was undertaken.

Results: Gene carriers had significantly worse recognition memory and scored higher in measures of irritability than controls. The groups also differed in terms of the factor structure of their psychiatric symptoms. None of the subjects qualified for a psychiatric diagnosis at the time of assessment.

Conclusion: The groups differed with respect to their profile of psychiatric symptoms. It is hypothesized that these differences are the expression of different mechanisms, i.e. that cognitive deficits relate more to genetic factors and neurotic complaints more to being brought up in a disturbed family background. Issues concerning instrument sensitivity, selection bias and the advantage of seriatim assessments are discussed.