Symptoms

Symptoms of Parkinson's disease usually develop gradually and are mild at first. They often begin on one side of the body before eventually affecting both sides. The order in which symptoms develop and their severity is different for each person.

Movement symptoms

The main symptoms of Parkinson's disease affect physical movement:

• Tremor - shaking that usually begins in the hand or arm and is more likely to occur when the limb is relaxed and at rest.
• Slowness of movement (bradykinesia) - physical movements become much slower than normal, which can make everyday tasks difficult and result in a slow, shuffling walk with very small steps.
• Muscle stiffness (rigidity) - stiffness and tension in the muscles, which can make it difficult to move and make facial expressions, and can result in painful muscle cramps.
• Poor balance and coordination -  balance problems tend to develop as the disease progresses and can increase the risk of falls.

Non-movement symptoms

Parkinson's disease can also cause a range of other physical and mental symptoms:

• Depression and anxiety
• Memory problems and mild cognitive impairment; in advanced stages, more significant cognitive changes and dementia can occur. Talk to a neurologist if you have concerns about cognitive symptoms.
• Sleep problems and excessive daytime sleepiness
• Loss of sense of smell, which sometimes occurs several years before other symptoms
• Swallowing difficulties
• Constipation
• Dizziness or fainting when standing up quickly
• Excessive sweating
• Nerve pain, including sensations of burning, coldness, or numbness

Causes and risk factors

Parkinson's disease is caused by the loss of nerve cells in the substantia nigra, a part of the brain that produces dopamine. Symptoms usually only begin to appear when around 60% to 80% or more of the nerve cell activity in this area has been lost.[4] The exact reason why these nerve cells die is not fully understood, but researchers believe a combination of genetic and environmental factors may be responsible.

Genetics

A number of genetic factors have been shown to increase a person's risk of developing Parkinson's disease. Parkinson's can run in families as a result of certain genes being passed from parent to child, but this is relatively rare. Most cases of Parkinson's disease do not appear to be directly inherited.

Environmental factors

Some research suggests that long-term exposure to certain environmental factors may contribute to the development of Parkinson's disease. These include pesticides and herbicides used in farming, industrial pollution, and traffic pollution. However, the evidence linking environmental factors to Parkinson's disease is not yet conclusive, and research is ongoing.

Risk factors

• Age - the risk of Parkinson's increases with age. Most people develop the condition after age 60.
• Sex - men are about 1.5 times more likely to develop Parkinson's disease than women.
• Family history - having a close relative with Parkinson's slightly increases your risk, though most cases are not inherited.
• Exposure to certain toxins - ongoing exposure to herbicides and pesticides may put you at a marginally increased risk.

Diagnosis and treatment

How is Parkinson's disease diagnosed?

There is no specific test for Parkinson's disease, which can make it challenging to diagnose. Doctors typically use a combination of a medical history review and a neurological examination to make a diagnosis. In some cases, imaging scans may be used to rule out other conditions. Because symptoms develop gradually, it may take time before a diagnosis is reached.

If you or someone you know has symptoms that may be consistent with Parkinson's disease, speak with a health care provider. They may refer you to a neurologist or specialist for further evaluation.

Treatment options

While there is currently no cure for Parkinson's disease, treatments are available to help reduce symptoms and maintain quality of life. Treatment is tailored to each person and may change over time as the condition progresses.

Medication

Medication is the most common treatment for Parkinson's disease. The most widely used medication is levodopa, which the brain converts into dopamine to help improve movement. Other medications include dopamine agonists, which mimic the effects of dopamine, and MAO-B inhibitors, which help prevent dopamine from breaking down in the brain. A specialist will work with you to find the right medication and dosage for your individual needs.

Supportive therapies

• Physical therapy - helps relieve muscle stiffness and joint pain through exercise and movement, and can improve walking, flexibility, and overall fitness
• Occupational therapy - helps identify and address challenges in daily activities such as dressing or getting around, and can help adapt your home environment to support independence
• Speech and language therapy - helps address swallowing difficulties and speech problems through targeted exercises and assistive technology
• Diet and nutrition - dietary changes can help manage some symptoms, such as increasing fiber intake to reduce constipation or adjusting meals to manage blood pressure changes

Surgery

For some people with more advanced Parkinson's disease, a surgical procedure called deep brain stimulation (DBS) may be an option. DBS involves implanting electrodes in specific areas of the brain that send electrical pulses to help regulate abnormal movement signals. It is not suitable for everyone and is typically considered when medication alone is no longer managing symptoms effectively. A specialist can help determine whether surgery is appropriate.

Living with Parkinson's disease

Many people with Parkinson's disease are able to lead full, active lives, particularly in the early stages of the condition. As the disease progresses, everyday activities may become more challenging, but with the right support and care, quality of life can be maintained for many years.

Exercise has been shown to be one of the most beneficial things a person with Parkinson's can do. Regular physical activity can help improve mobility, balance, and mood. Many communities offer exercise programs specifically designed for people with Parkinson's, such as boxing, dance, and cycling programs.

Staying connected to friends, family, and support groups can also make a significant difference. Support groups offer an opportunity to connect with others who understand the challenges of living with Parkinson's and share practical advice and encouragement.