Apathy is a multidimensional syndrome that frequently presents in stroke survivors and is characterised by a loss in motivation and initiative, reduced social interactions, and neutral emotionality. Apathy affects cognitive functioning, everyday activity including social life, and functional recovery. Despite the prevalence of apathy among the sequelae of stroke, an understanding of this symptom trajectory and its effect on patient and carer’s quality of life needs to be clarified.

The research presented in this thesis mainly focuses on a prospective longitudinal study conducted in three acute stroke services in the East of England, UK. The main goal of the study was to evaluate the prevalence of post-stroke apathy and its association with outcome, mood, and cognition. Findings show that overall apathy tends to increase over one year after stroke and that different groups of patients present with different symptom trajectories. Moreover, the study results show that post-stroke apathy presents with specific patterns of impaired dimensions, which may vary depending on the measurement technique used, including method of scoring.

After analysing the relationship between apathy, disability, and quality of life, my findings suggest that depression, more than apathy, might play an important role in determining functional outcome and recovery. The investigation of neurobiological bases of apathy found an association with white matter pathology, reinforcing the idea that chronic ischaemia coupled with acute lesions might set up a cascade of events leading to apathy. A new study was then set up to investigate the effects of apathy on carers of patients with small vessel disease and found that apathy is associated with higher care burden and distress. The results of this study pave the way for targeted intervention approaches.

Overall, this thesis suggests that apathy is a symptom or syndrome presenting in about 20% of stroke patients and affecting patient and carer lives alike. A comprehensive characterisation of apathy holds clinical relevance and encourages the further development of new apathy treatments.