Objective: Apathy has been reported as a possible adverse effect of deep brain stimulation of the subthalamic nucleus (STN-DBS). We investigated the prevalence and severity of apathy in 22 patients with Parkinson's disease (PD) who underwent STN-DBS, as well as the effects of apathy on quality of life (QOL).
Methods: All patients were assessed with the Lille Apathy Rating Scale (LARS), the Apathy Scale (AS), and the Parkinson's Disease Questionnaire and were compared to a control group of 38 patients on pharmacotherapy alone.
Results: There were no significant differences in the prevalence or severity of apathy between patients who had undergone STN-DBS and those on pharmacotherapy alone. Significant correlations were observed between poorer QOL and degree of apathy, as measured by the LARS (p<0.001) and the AS (p=0.021). PD-related disability also correlated with both apathy ratings (p<0.001 and p=0.017, respectively).
Conclusion: Our findings suggest that STN-DBS is not necessarily associated with apathy in the PD population; however, more severe apathy appears to be associated with a higher level of disability due to PD and worse QOL, but no other clinico-demographic characteristics.
Keywords: Apathy; Parkinson’s disease; behavior; deep brain stimulation; quality of life; subthalamic nucleus.