PSYCHOLOGICAL EFFECTS OF PRESYMPTOMATIC DNA TESTING FOR HUNTINGTONS-DISEASE IN THE DUTCH PROGRAM

This study assessed the 6-month follow-up effects of presymptomatic DN A testing for Huntington's disease (HD) in 73 individuals at 50% prior risk who were identified either as carriers of the HD gene (N = 29) o r as noncarriers (N = 44). The subject's knowledge of being a gene car rier was expected to induce intrusive emotions, denial-avoidance behav ior, and pessimistic expectancies of the future and adjustment problem s. The Impact of Event Scale, the Beck Hopelessness Scale, and the Gen eral Health Questionnaire were used as standard measures of psychologi cal distress. At the disclosure of the test results, carriers had a st rong increase in pessimistic expectations but showed a decline to base line levels 6 months later. Noncarriers reported a steep decline in ho pelessness compared with their pretest conditions but had increased sc ores after 6 months. Six months after the disclosure of the test resul ts, both gene carriers and noncarriers reported a significant decrease in unwanted intrusive thoughts about HD. Carriers showed a slight inc rease in denial-avoidance behavior, whereas noncarriers showed a clear decrease. Our observations might indicate that tested individuals fou nd relief from the prior psychological distress and that they were abl e to acknowledge the impact of the test result on their future. An unr esolved question is how the foreknowledge will affect carriers as they approach the impending onset of the disease. Longer observation perio ds (> 6 months after disclosure) are required to study changes of the impact of DNA test results over time.