Risk Factors for Suicidal Ideation in People at Risk for Huntington’s Disease

Background: Suicidal ideation (SI) and attempts are increased in Huntington's disease (HD), making risk factor assessment a priority. Objective: To determine whether, hopelessness, irritability, aggression, anxiety, CAG expansion status, depression, and motor signs/symptoms were associated with Suicidal Ideation (SI) in those at risk for HD. Methods: Behavioral and neurological data were collected from subjects in an observational study. Subject characteristics were calculated by CAG status and SI. Logistic regression models were adjusted for demographics. Separate logistic regressions were used to compare SI and non-SI subjects. A combined logistic regression model, including 4 pre-specified predictors, (hopelessness, irritability, aggression, anxiety) was used to assess the relationship of SI to these predictors. Results: 801 subjects were assessed, 40 were classified as having SI, 6.3% of CAG mutation expansion carriers had SI, compared with 4.3% of non-CAGmutation expansion carriers (p = 0.2275). SI subjects had significantly increased depression (p < 0.0001), hopelessness (p < 0.0001), irritability (p < 0.0001), aggression (p = 0.0089), and anxiety (p < 0.0001), and an elevated motor score (p = 0.0098). Impulsivity, assessed in a subgroup of subjects, was also associated with SI (p = 0.0267). Hopelessness and anxiety remained significant in combined model (p < 0.001; p < 0.0198, respectively) even when motor score was included. Conclusions: Behavioral symptoms were significantly higher in those reporting SI. Hopelessness and anxiety showed a particularly strong association with SI. Risk identification could assist in assessment of suicidality in this group.