Parkinson’s disease (PD) is the second most common neurodegenerative disorder worldwide, affecting 2-3% of the population aged 65 or over. In Australia, it affects >120,000 people, and a new patient is diagnosed every 45 minutes.
PD is a progressive, neurological condition; typically defined by its motor features, including rigidity, bradykinesia, gait disturbance, and tremor. However, PD patients also experience a number of non-motor symptoms, including REM sleep behaviour disorder, constipation, urinary incontinence, orthostatic hypotension, depression, apathy, hyposmia, cognitive impairment and, importantly, a 6x higher risk of dementia compared to the general population.
PD pathology is characterized by progressive neuronal loss in specific areas of the substantia nigra in the brain that result in dopamine deficiency, and the accumulation of abnormal aggregates of the alpha-synuclein protein inside nerve cells (these aggregates are known as Lewy bodies).
The causes of PD are complex. Nearly 15% of PD cases have a family history, and 1-5% of PD patients have a monogenic form of the disease. The remainder are considered sporadic or idiopathic cases, without family history and thought to result from a combination of genetic and environmental factors.
Due to population aging and increased life expectancy, the prevalence and associated costs of PD are expected to increase dramatically over coming decades. There is great variation in terms of the onset, intensity and progression of PD’s clinical features between individuals.
There is currently no cure available for Parkinson’s disease. Treatment options focus on symptom management and can be pharmacological and non-pharmacological.