Apathy in Movement Disorders (Parkinson’s Disease, Huntington’s Disease)

Abstract

Apathy is a disabling neuropsychiatric symptom occurring in movement disorders such as Parkinson’s disease (PD) and Huntington’s disease (HD). Early identification, diagnosis, and timely treatment of apathy in movement disorders are very relevant, since apathy is related to poor disease outcome, reduced daily functioning and quality of life, and caregiver distress. This chapter discusses the phenomenology and assessment tools for screening and diagnosing apathy in PD and HD patients, including psychometric properties of several tools. Demographic, clinical, and neuropsychological correlates underlying apathy related to PD and HD are also reviewed. Furthermore, structural and metabolic brain correlates of apathy in both PD and HD are discussed: frontal-subcortical system(s) dysfunction in particular may lead to the onset of apathy. Finally, the chapter provides an overview of pharmacological treatments and their efficacy in improving apathy in PD and HD.