Psychological functioning before predictive testing for Huntington's disease: the role of the parental disease, risk perception, and subjective proximity of the disease

Background-Psychometric testing of participants in predictive DNA Huntingon 's disease (HD) has shown that 15% of the subjects at risk for HD had at le ast mild depression or a high score for general anxiety or both in the pre- test period. The main aim of the study was the delineation of variables ass ociated with pre-test distress of applicants for predictive testing for HD. Based on theoretical considerations, four specific hypotheses were tested regarding the role of (1) the test participant's age at the (perceived) par ental onset of HD, (2) the affected parent's sex, (3) the perception of the risk for HD, and (4) the subjective proximity of the disease. Secondly, th ese four variables were used in multiple regression analyses to select the best predictors of pre- and post-test psychological functioning tone year a fter the test). Increasing the understanding of pre- and post-test distress is important for developing better counselling and support strategies for test applicants. Methods-Data were collected by means of clinical interviews and psychometri c questionnaires during the pre- and posttest tone year after the test) cou nselling sessions for predictive testing for HD. Results-We found significant associations of the participant's age at the p arental onset, the subjective proximity of the disease onset, and the perce ived risk with pre-test psychometric measures of psychological functioning. Multiple regression analyses showed that the best predictors of pre-test f unctioning were the perceived proximity of the disease onset and its intera ction with risk perception. Regarding post-test functioning, none of the pr oposed variables had a unique contribution beyond that accounted for by pre -test psychological functioning. Conclusions-Test participants who are close to the perceived age of onset o f HD and who have a pessimistic risk perception should be given special att ention during pre-test counselling because of their possible negative affec tive condition at that time. Pre-test psychological measures were the best predictors of post-test distress, irrespective of the test result. Suggesti ons for future longitudinal research are formulated. This kind of retesting of search should enable clinical geneticists and mental health professiona ls to refine the pre- and post-test counselling strategies for predictive D NA testing, not only for HD, but also for other incurable late onset disord ers.