Epidemiology of Parkinson’s Disease
Parkinson’s disease is a chronic, progressive neurodegenerative disease that is characterized by both motor and non-motor features. It is the most common cause of parkinsonism- a term used to describe the motor symptoms. Parkinsonism can be caused by other diseases or can be drug-induced. PD is the second most common neurodegenerative disease after Alzheimer's disease and its prevalence is estimated between 100 and 300/100,000. The cardinal signs of PD are rest tremor, bradykinesia (slowness of movement) and muscular rigidity; often referred to as the classical triad. Both rigidity and bradykinesia occur in more than 80% of patients; while tremor occurs in 70-90% of patients and primarily involves the hands. Another feature; called postural instability, occurs in 50% of patients. These symptoms are due to progressive degeneration of dopaminergic neurons in the substantia nigra, leading to the loss of dopaminergic function.
Parkinson’s disease is a chronic neurodegenerative disease that is characterized by three main motor features: rest tremor, bradykinesia and muscular rigidity. These symptoms are due to the loss of dopaminergic neurons in the substantia nigra which leads to decreased levels of dopamine in the striatum negatively affecting the motor control. Other features include hyposmia and constipation. PD is also characterized by presence of Lewy bodies in the substantia nigra. Its incidence increases with age and is more common in men. A cure hasn’t been found yet; but improvement of motor functions is possible.