Cross-Sectional Study on Prevalences of Psychiatric Disorders in Mutation Carriers of Huntington's Disease Compared With Mutation-Negative First-Degree Relatives

Objective: To investigate the prevalences of formal DSM-IV diagnoses in pre-motor-symptomatic and motor-symptomatic mutation carriers at different stages of Huntington's disease compared to a control group of first-degree noncarrier relatives and the general population. Method: Between May 2004 and August 2006, 154 verified mutation carriers and 56 verified noncarriers were recruited from the outpatient clinics of the Neurology and Clinical Genetics departments of Leiden University Medical Center and from a regional nursing home. To assess the 12-month prevalences of DSM-IV diagnoses, the sections for depression, mania, anxiety, obsessive-compulsive disorder, and psychosis/schizophrenia of the Composite International Diagnostic Interview were used. Prevalences in the Dutch general population were extracted from the Netherlands Mental Health Survey and Incidence Study (NEMESIS). Results: Both presymptomatic and symptomatic mutation carriers portrayed significantly more major depressive disorder (p = .001 and p < .001, respectively) and obsessive-compulsive disorder (p = .003 and p = .01, respectively) than the general population. Symptomatic mutation carriers also showed an increased prevalence (p = .01) of nonaffective psychosis. Psychiatric disorders were more prevalent, although not significantly (p = .06), in mutation carriers compared to first-degree relatives who were noncarriers. Noncarriers did not differ from the general population. Conclusion: Psychiatric disorders occur frequently in Huntington's disease, often before motor symptoms appear. In addition, first-degree noncarrier relatives do not show more psychiatric disorders compared to the general population, although they grew up in comparable, potentially stressful circumstances. Taking these findings together, psychopathology in Huntington's disease seems predominantly due to cerebral degeneration rather than to shared environmental risk factors.