There are five commonly recognized stages of Parkinson’s. Neurologists stage Parkinson’s based on the way the condition typically progresses. However, symptoms of Parkinson’s vary by the type of parkinsonism and between individuals. An individual with Parkinson’s will not necessarily experience all or even most symptoms and may not experience them at the same stage in which others experience them. Parkinson’s is a progressive disease, which means that symptoms worsen gradually over time, new symptoms appear, and disability accumulates.
Assessing the stage of Parkinson’s helps anticipate disabilities and plan accordingly for care.
The stages of Parkinson’s are based on the Hoehn and Yahr scale introduced in 1967. The Hoehn and Yahr staging system focuses on disability caused by motor symptoms such as bradykinesia (slowed movements), tremor, and loss of balance. Some neurologists also use a newer scale called the Unified Parkinson’s Disease Rating Scale (UPDRS). The UPDRS scale takes into account changes in mood, cognitive function such as thinking and remembering, and social behavior.
Motor symptoms occur on one side of the body only. There is minimal or no disability.
Motor symptoms worsen and begin to affect both sides of the body. There may be difficulty walking and changes in posture, facial expression, and voice. Daily activities become harder and take longer.
In the middle stage of Parkinson’s, loss of balance becomes apparent and falls are more common. Motor symptoms make it difficult to eat, dress, and perform self-care, but the person is still capable of living alone.
At stage 4, a person is no longer able to live alone. Disability is severe, and the person requires help with many daily tasks. They may or may not be able to stand and walk without assistance. Many people begin using walkers at this stage.
During stage 5, the person cannot rise from a chair or bed without help. Motor symptoms include stumbling and freezing. They may lose the ability to stand or walk, and a wheelchair becomes necessary. Assistance is required around the clock for all activities. Some people begin to experience psychotic symptoms such as hallucinations or delusions.
A newer theory of Parkinson’s progression called Braak's hypothesis suggests that Parkinson’s may begin years before motor symptoms develop. According to Braak’s hypothesis, loss of smell and digestive symptoms such as constipation are the earliest signs of Parkinson’s, showing up many years before motor issues. While these early symptoms do not show up on an official Parkinson’s stage yet, many researchers are working on ways to identify and treat Parkinson’s earlier, even before stage 1.