Importance of psychiatric examination in predictive genetic testing for Huntington disease

Abstract

Background and purpose

Huntington disease (HD) is an autosomal dominant hereditary neurodegenerative disease with multiplication of CAG triplet in the short arm of chromosome 4, manifested by motor symptoms, cognitive dysfunction progressing to dementia, and various types of neuropsychiatric disorders. The diagnosis of HD is confirmed by a genetic test, which may also be carried out presymptomatically.

Material and methods

We studied differences in psychiatric examination and psychometric measures among the 52 people at risk of HD, who were recommended to postpone or to continue in the predictive protocol. In addition to the psychiatric examination, we administered the Eysenck Personality Questionnaire (EPQ-A), the Symptom Checklist 90 (SCL-90), and quality of life questionnaire (MANSA).

Results

People at risk of HD with the recommended test postponement showed lower rate of neuroticism and EPQ-A lie score, higher values on the phobia and the so-called ‘positive symptom distress index’ in SCL-90 and lower quality of life than people at risk of HD with the recommendation to continue.

Conclusions

Our results indicate that the formalized testing does not bring significant information whereas the clinical psychiatrie examination remains the main decisive factor in the recommendation to perform a predictive genetic test. The motivation of applicants is considered as the most important factor in the decision-making proces.