Parkinson's disease

Abstract

Parkinson's disease (PD) is a common neurodegenerative condition, affecting 2–3% of individuals >65 years of age. Although it is defined as a movement disorder, patients also experience a range of non-motor symptoms, reflecting pathology that is more widespread than originally thought in the peripheral and autonomic nervous system as well as the brainstem and cortex. Some non-motor symptoms emerge years before motor problems. This prodromal stage of PD may represent the optimal time for intervention with future disease-modifying therapies. Patients differ in the extent of non-motor and motor symptoms at presentation, and in the speed of evolution. This is partly because of genetic factors and is to some extent predictable in early disease. Here, we discuss the natural history of PD and provide an update on its genetic and pathological basis before reviewing motor and non-motor symptomatology. We discuss currently available therapies and their complications, before reviewing new therapeutic developments and the need to target these precisely to particular disease subtypes that are now better defined at an early disease stage.