Psychological implications of predictive genetic testing for amyotrophic lateral sclerosis: demographics, motivations, and potential risks of testing

Predictive genetic testing allows individuals at-risk of amyotrophic lateral sclerosis (ALS) to ascertain their risk of developing this disease. However, guidelines for testing may not be well-informed or able to support at-risk individuals due to the lack of ALS-specific research. This study thus assessed the demographic characteristics of individuals who test, their motivations for testing, and the potential risks of testing. Online questionnaires were administered to 104 participants with a family history of ALS including 38 individuals who had not received predictive testing for ALS, 43 individuals who had received a positive test result, and 23 individuals who had received a negative test result. Results found that individuals who received testing were more likely to correctly answer specific questions on the genetic aspects of ALS and less likely to be unsure of what gene ran in their family. The most common motivation endorsed for testing was to inform future planning. Regarding psychological motivations of testing, there were no differences between testers and non-testers on levels of self-efficacy or health anxiety. However, testers were more likely to perceive themselves as a carrier of the ALS gene than non-testers. Testers who endorsed relief from uncertainty as a testing motive had higher levels of health anxiety. Regarding potential risks of testing, there were no differences in family functioning, subjective well-being, or survivor guilt by testing status. However, ALS-specific distress was found to be significantly higher in negative testers than positive testers, but not non-testers. These findings suggest that guidelines should consider providing support on future planning when assisting individuals with testing decision-making, assess and consider perceived carrier status and relief from uncertainty as motivators for testing that may relate to poor outcomes, and inform individuals of and provide support for potential distress reactions in individuals who receive a negative result.