Longitudinal Neuropsychological Study of Presymptomatic c.709-1G>A Progranulin Mutation Carriers.

The assessment of individuals from families affected by familial frontotemporal dementia (FTD) allows the evaluation of preclinical or pre-diagnosis disease markers. The current work aims to investigate the existence of a cognitive phase in GRN mutation carriers before overt clinical symptoms begin. We performed a longitudinal neuropsychological analysis (three assessments in 4 years) in a group of presymptomatic c.709-1G>A progranulin (GRN) (n=15) mutation carriers and non-carrier relatives (n=25) from seven FTD families. GRN mutation carriers showed subtle decline over the longitudinal follow-up in several different domains (namely, attention, facial affect recognition, decision-making, language, and memory). The differences between groups were most marked in the facial affect recognition test, with improvement in the non-carrier group and decline in the GRN mutation carrier group, with very large effect sizes. Facial affect recognition may decline before clinical diagnosis and makes the adapted version of the Picture of Facial Affect a potential candidate for early detection of GRN-associated FTD. (JINS, 2019, 25, 39-47).