A guide to nonmotor symptoms in Parkinson's disease

Parkinson’s disease is a neurodegenerative disorder that affects the brain. Neurodegenerative disorders are conditions where cells in the central nervous system (the brain and spinal cord) deteriorate and die. This disrupts how the central nervous system communicates with other parts of the body.

The primary symptoms of Parkinson’s disease

With Parkinson’s disease, the loss of cells begins in the regions of the brain that control movement. The primary symptoms of Parkinson’s disease are called “motor symptoms” or “movement symptoms.” These include

• Tremor. This is often the earliest motor symptom. Tremor is involuntary shaking or trembling when at rest. It often affects the hands, arms, legs, jaw, and face.
• Bradykinesia. This is the medical term for slowed movement. It can affect voluntary movements (like walking or standing up) and involuntary movements (like blinking).
• Rigidity. The muscles of the arms and legs become stiff, tight, and inflexible. Rigidity can cause pain and achiness, and it can limit a person’s ability to move.
• Gait abnormalities. A person may walk differently as a result of Parkinson’s disease. This can include walking with slow, shuffling steps, reduced arm swing, and stooped posture.
• Postural instability. A person with PD may struggle to maintain balance, coordinate movements, and react to changes or movement around them, putting them at risk for falls.

The nonmotor symptoms of Parkinson’s disease

While the primary symptoms of Parkinson’s disease are motor symptoms, the condition can also cause a wide spectrum of nonmotor (non-movement) symptoms. Some nonmotor symptoms can begin before motor symptoms—sometimes many years before. Parkinson’s disease can also contribute to other health conditions and complications, especially as the disease progresses.

Addressing nonmotor symptoms is an important part of treating and managing Parkinson’s disease. As a person living with Parkinson’s disease or a caregiver for someone living with Parkinson’s disease, it’s important to be aware of the nonmotor symptoms that can occur.

• Cognitive changes. These are problems with reasoning and memory. Symptoms can vary in severity, from mild forgetfulness to dementia (severe symptoms that interfere with everyday activities).
• Mental health conditions. Depression and anxiety affect many people with Parkinson’s disease. Many caregivers also experience mental health conditions.
• Sleep disorders. A person may experience insomnia, excessive daytime sleepiness, restless leg syndrome, or disordered breathing during sleep (such as sleep apnea). Also common is rapid eye movement (REM) sleep behavior disorder, which causes a person to act out vivid (often unpleasant) dreams during REM sleep cycles.
• Psychosis. Parkinson’s disease (PD) psychosis causes symptoms that involve a loss of contact with reality, such as hallucinations (seeing, hearing, or sensing things that are not there) and delusions (false beliefs not based in reality).
• Decreased sense of smell. Called hyposmia, this may be one of the earliest signs of Parkinson’s disease and can occur years before a diagnosis.
• Autonomic dysfunction. Parkinson’s disease can also affect the parts of the nervous system that control automatic or involuntary movements. This can lead to numerous issues including urinary incontinence, constipation, sexual dysfunction, and sudden drops in blood pressure.
• Problems with speech and swallowing. If Parkinson’s disease affects the muscles of the face, mouth, and throat, it can cause problems with speech and swallowing.
• Fatigue. This is extreme mental and/or physical tiredness. It can occur at any stage of the disease, and it can have a significant impact on a person’s quality of life.
• Skin symptoms. Skin changes are common among people who have Parkinson’s disease, and can include oily skin, scales, itching, inflammation, dry skin, excessive sweating, and too little sweating. People with Parkinson’s disease are also at an increased risk of skin cancer.
• Vision changes. Parkinson’s disease can affect how the eyes and eyelids move, causing problems with vision (such as double vision) and dry eye. Blurred vision can be a side effect of some medications used to treat Parkinson’s disease.
• Weight changes. Unintentional weight loss can have many causes related to Parkinson’s disease. Some therapies used to manage Parkinson’s disease can cause weight gain.
• Bone and joint problems. Muscle rigidity and changes to posture can cause problems with the bones and joints, including the spine. People with Parkinson’s disease are also at an increased risk of falls, fractures, and osteoporosis (bone loss).

While these symptoms are associated with Parkinson’s disease, many can have other causes or contributing factors. For example, vision problems can be caused by age-related macular degeneration and/or cataracts.

The only way to know what is causing a symptom—and receive appropriate treatment—is to visit a healthcare provider for an evaluation. Any new or worsening symptom should always be discussed with a healthcare provider as soon as possible.