Psychological studies in Huntington's disease: making up the balance
- Magdalena Duisterhofa,
- Rutger W Trijsburga,
- Martinus F Niermeijerb,
- Raymund A C Roosc,
- Aad Tibbena,b,c
- aDepartment of Medical Psychology and Psychotherapy, Erasmus University Medical Centre Rotterdam, Dr Molewaterplein 50, Room CF 226, 3015 GE Rotterdam, The Netherlands, bDepartment of Clinical Genetics, Erasmus University Medical Centre Rotterdam, Rotterdam, The Netherlands, cDepartment of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
- Dr Duisterhof,
Editor—Huntington's disease (HD) is an incurable neurodegenerative disease, characterised by involuntary movements, changes in behaviour and personality, and cognitive impairment, leading to death 15 to 20 years after its onset.1 HD is an autosomal dominantly inherited disorder, the gene for which is localised on the short arm of chromosome 4.2 Subjects carrying the gene will develop the disease in the absence of other causes of death. The mean age of onset is 40 years, by which time gene carriers may have passed on the gene to their offspring. The age of onset ranges from 2 to 75 years3 so that those at risk (that is, risk carriers at 50% or 25% genetic risk) can never be sure of having escaped HD.
Since 1986, presymptomatic DNA testing using genetic linkage analysis has made it possible for risk carriers to have their risk modified to approximately 98% or 2%. After identification of the HD gene mutation in 1993, CAG repeat size analysis of the huntingtin gene allowed complete certainty of either having or not having HD.2
Risk carriers, being raised in a family in which HD played a major role, could be expected to have specific adjustment problems. Yet, only one study addressed the psychological functioning of people at risk for HD before presymptomatic testing was introduced. Most psychological studies were started when clinicians and researchers became concerned about the effects of a presymptomatic test on people at risk.
The aim of this article is to review studies addressing psychological and psychiatric adjustment of people at risk for HD. The methods used by the studies (that is, objectives, inclusion and exclusion criteria, recruitment, assessment, design, and statistical analyses) and their results are presented. General trends and limitations of the present work are described and a direction …