Parkinson’s disease is a progressive neurological disorder that affects how the brain controls movement. It develops gradually, often beginning with subtle symptoms that are easy to overlook.

The condition was first described in 1817 by the British physician James Parkinson. Today it is recognized as one of the most common neurodegenerative diseases worldwide, affecting millions of people.

Causes

Parkinson’s disease is caused by the loss of brain cells that produce dopamine, a chemical messenger essential for smooth and coordinated movement. As dopamine levels decline, movements become slower, stiffer and more difficult to control.

At the cellular level, Parkinson’s disease is associated with the buildup of an abnormal protein called alpha-synuclein inside brain cells. These clumps, known as Lewy bodies, are a pathological hallmark of the disease and are believed to disrupt normal cell function and survival.

While getting older increases the risk of Parkinson’s disease, it’s not a part of normal aging. Most people are diagnosed in their 60s, though younger people can also be affected. Genetics and environmental exposures can both contribute to developing Parkinson’s, but in most cases the exact cause is unknown.

Common symptoms

The most well-known features of Parkinson’s disease are motor symptoms that affect movement, including:

• Slowness of movement (bradykinesia), making everyday tasks take longer.
• Muscle stiffness or rigidity, which can limit range of motion.
• Tremor, often beginning in one hand while at rest.
• Problems with balance and posture, increasing the risk of falls.

Symptoms typically begin on one side of the body and often remain uneven as the disease progresses.

Beyond movement

Parkinson’s is not only a movement disorder. Many people experience nonmotor symptoms that can appear years before movement problems, including:

• Constipation and other digestive issues.
• Sleep disturbances, such as acting out dreams.
• Loss of smell.
• Fatigue, depression or anxiety.
• Changes in thinking or memory.

For many people, these symptoms can be just as disruptive as motor difficulties.

Living with Parkinson’s

There is no cure for Parkinson’s disease, but treatments are available to significantly improve quality of life. Medications help to replace or mimic dopamine, reducing movement symptoms. Exercise, physical therapy and lifestyle adjustments such as regular aerobic exercise, strength and balance training, adequate sleep, stress management and a balanced, nutrient-rich diet, are key components of care. In some cases, surgical treatments such as deep brain stimulation may help tame symptoms as well.

Around the world, we are collectively living longer. As research into earlier diagnosis and better therapies continues to expand, science is offering hope for improved outcomes in the future.