What are the stages of Parkinson’s disease?

As a progressive disease, Parkinson’s disease symptoms occur in stages:

• Stage one: Symptoms are mild and generally not severe enough to interfere with typical daily function or tasks. Symptoms during this stage may also be easily missed. If any are noticed, it is usually subtle changes that are picked up by friends and family. The easiest changes to note are a person’s walk or gait, posture and facial expression. Alternatively, a person may note subtle changes in their own movement ability or a tremor that has developed on one side.
• Stage two: Symptoms are classified as moderate and typically become more noticeable (more developed or occurring more frequently). The most obvious symptoms are usually tremors, shaking, body stiffness, and changes in facial expression. A person may note that it takes a little longer to complete a task (requiring muscle movement) or a change in posture or speech. Symptoms such as tremors may begin to affect both sides of the body (one side may be worse than the other). Progression from stage one to two can take anywhere between a few months to several years. Progression rate is unique to an individual and cannot be medically predicted.
• Stage three: This stage typically marks a turning point in the progression of the condition. Symptoms generally are similar to stage two, but a person will now begin to notice problems with balance and a decrease in reflexes. A person may experience frequent falls and also struggle with slower overall movements, which affect the ability to independently perform many daily tasks. A person is not incapable of completing tasks by themselves at all at this stage, but will certainly notice a distinctive change that may require assistance from time to time.
• Stage four: At this stage, living alone (independence) may become problematic. Significant decreases in movement (and delayed reaction times) may mean that a person is unable to walk or function unaided. Standing unaided may be possible, but not usually walking. Assistive devices such as a walker (or Zimmer frame) may be necessary and make moving about less problematic (i.e. preventing falls). A person will require assistance with most tasks from this stage onwards.
• Stage five: Progressively decreased motion and freezing may make it increasingly difficult for a person to walk, even with an assistive device. At this advanced stage, a wheelchair may become necessary, as well as around-the-clock assistance. Delusions, hallucinations and confusion are common and often result in the development of dementia. Up to 75% of individuals at this advanced stage can develop dementia.

How do doctors determine these stages?

Many doctors make use of a Unified Parkinson’s Disease Rating Scale (UPDRS), which allows them rate cognitive difficulties which hinder day-to-day lifestyle and ability to perform regular tasks. This scale also enables doctors to assess the effectiveness of treatment during the progressive stages of the condition. The scale is thorough and complex and allows doctors the ability to gain a detailed perspective of a person’s condition. It examines the overall state of health of a person, and not just motor or mobility troubles.

Others make use of another rating system known as Hoehn and Yahr, which rates a person’s symptoms on a scale of 1 to 5, assessing motor difficulties. A doctor uses the rating scale to assess the progression of symptoms – early stages will be marked as 1 and 2, mid-stages are rated at 3, with the advanced stages being 4 and 5. This rating does not take into account cognitive difficulties that the UPDRS system uses.