Apathy and executive functioning among non-demented community-dwelling elderly individuals in an everyday environment: the mediating effect of impulsivity.

Abstract

Apathy is common in normal ageing and widely recognized as a predictor of cognitive decline, especially in executive functions. Much less characterized than apathy in the elderly is impulsivity, which increases with ageing. It is also frequently described in comorbidity with apathy in various clinical populations, in whom it is associated with poorer executive functioning. In the present study, by capitalizing on a multidimensional approach, we explore the mediating role of facets of impulsivity on the bidirectional relationships between apathy dimensions and executive functioning in non-demented community-dwelling elderly individuals in daily life. A sample of non-demented community-dwelling older adults (n= 101) completed self-rated questionnaires. Apathy was measured by the Apathy Evaluation Scale; impulsivity was examined through the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency (UPPS-P) Impulsive Behaviour Scale; and executive functioning in daily life was assessed by the Behaviour Rating Inventory of Executive Function-Adult (BRIEF-A). Two models positing mediation were tested using conditional process modelling. Hierarchical regressions controlling for depressive symptoms indicated that the cognitive apathy dimension was associated with the UPPS-P facets sensation seeking, lack of perseverance, and premeditation. Among the UPPS-P facets, lack of perseverance and negative urgency were found to contribute significantly to BRIEF-A Metacognitive index variance. Finally, in both models, lack of perseverance was found to totally mediate the relationship between cognitive apathy and the BRIEF-A Metacognitive index. These preliminary findings suggest that, in normal ageing, apathy may share an overlap with impulsivity, contradicting the notion they represent opposite ends of a single behavioural spectrum. Our results argue for bidirectional relationship between a specific apathy dimension (i.e. cognitive apathy) and executive functioning. Moreover, they shed new light on the underlying psychological process implicated (i.e. lack of perseverance) among older adults without dementia and represent an interesting prospect for psychological interventions.