Parkinson's disease is a neurological disorder characterized by four cardinal signs: postural instability, slow or interrupted movements (bradykinesia), rigidity, and tremors.

The disease is progressive, meaning symptoms worsen gradually over time. Parkinson’s disease can begin several years before symptoms become noticeable. Early indicators often include difficulty standing up from a chair, speaking softly, and writing more slowly. Non-motor symptoms affecting digestion, mental health, and sleep can also appear early and are sometimes among the first signs. Over time, Parkinson’s disease can lead to Parkinson’s dementia, a condition marked by severe cognitive and memory problems.

As the second most common neurological disorder worldwide, Parkinson’s disease affects approximately 2% to 3% of people over the age of 65. It can have a significant impact on both physical and mental health. Below is an overview of the signs and symptoms of Parkinson's disease.

Cardinal Symptoms

Parkinson’s disease is caused by the degeneration and death of brain cells in the substantia nigra, a part of the brainstem that regulates motor skills and balance. The primary, or "cardinal," symptoms of Parkinson's disease affect movement and coordination:

  • Bradykinesia: Refers to slowing or consistent interruption of physical movement, causing fatigue, lack of coordination, and weakness. It is present in most people at the onset of symptoms.
  • Postural Instability: Involves difficulty maintaining an erect posture, leading to balance problems and an increased risk of falls. This symptom typically appears in the later stages of the disease.
  • Rigidity: Characterized by muscle stiffness and resistance to movement or pressure. Rigidity often begins on one side of the body and can result in stooped posture, reduced arm swing while walking, and a "locking" of the hand joints.
  • Tremors: Involves uncontrollable shaking of the arms, hands, feet, jaw, tongue, or lips. Tremors usually start on one side and occur when the body is at rest, decreasing during movement.

Cognitive Symptoms

Approximately one-quarter to one-third of people with Parkinson’s disease experience cognitive decline or dementia. Symptoms include difficulties with concentration, memory problems, and trouble focusing on tasks. Cognitive changes can develop slowly or progress rapidly.

Parkinson's dementia is a type of Lewy body dementia, caused by deposits of a protein called alpha-synuclein in the brain. This form of dementia can significantly reduce a person's quality of life and ability to live independently.

Psychosis and visual hallucinations are also common, affecting 20% to 40% of individuals taking medications for Parkinson's. Psychosis may worsen over time and increase the risk of developing Parkinson’s dementia.

Motor Symptoms

In addition to the cardinal signs, Parkinson's disease can cause a range of motor symptoms affecting different parts of the body:

Craniofacial Symptoms

  • Difficulty swallowing (dysphagia)
  • Excessive drooling
  • Difficulty coordinating muscles for speaking and breathing (hypokinetic dysarthria)
  • Reduced facial expression (hypomimia)
  • Quiet, breathy, or monotone speech (hypophonia)
  • Decreased spontaneous blinking

Visual Symptoms

  • Blurry vision due to reduced visual focus
  • Difficulty shifting eye focus (hypermetric saccades)
  • Impaired contrast sensitivity, affecting the ability to distinguish patterns and textures
  • Impaired convergence, leading to difficulty focusing on near objects
  • Impaired vestibulo-ocular reflex, affecting eye stability during head movements
  • Difficulty opening eyes voluntarily (lid-opening apraxia)

Musculoskeletal Symptoms

  • Forward bending of the spine (camptocormia)
  • Involuntary muscle contractions (dystonia)
  • Abnormal spinal curvature (kyphosis or scoliosis)
  • Small, cramped handwriting (micrographia)
  • Involuntary muscle jerking (myoclonus)
  • Sideways bending of the spine (Pisa syndrome)

Gait Abnormalities

Changes in walking pattern, known as "Parkinsonian gait," are common. These include shuffling, short steps, sudden stops or freezing during walking, and festination, where the person unconsciously speeds up repetitive movements.

Non-Motor Symptoms

Non-motor symptoms can appear before the motor symptoms and significantly affect quality of life. They include:

Mental Health Issues

  • Anxiety: Persistent feelings of worry and fear, often accompanied by depression.
  • Apathy: Loss of interest, motivation, and emotional expression.
  • Depression: A common issue involving sadness, reduced interest in activities, and low mood affecting daily life.

Sleep Disorders

Sleep disturbances are common in Parkinson’s disease, affecting around two-thirds of people with the condition. These disturbances include:

  • Excessive daytime sleepiness
  • Insomnia
  • REM sleep behavior disorder (RBD), causing physical activity during dreaming
  • Restless legs syndrome (RLS), an uncontrollable urge to move the legs at night

Fatigue resulting from sleep problems is often an early sign of the disease.

Autonomic Dysfunction

Parkinson's disease can interfere with bodily functions that operate automatically, such as:

  • Constipation
  • Excessive sweating (diaphoresis)
  • Difficulty swallowing food
  • Low blood pressure upon standing (orthostasis)
  • Sexual dysfunction
  • Urinary incontinence

Other Symptoms

Loss of the sense of smell and various forms of pain, including tingling, burning, or sharp pain in different body parts, are also common among people with Parkinson’s disease.

When to Contact a Healthcare Provider

You should contact a healthcare provider if you experience symptoms like tremors, muscle stiffness, or difficulty with movement or balance. Medical attention is also necessary if you experience:

  • Cognitive difficulties, such as trouble concentrating or remembering
  • Difficulty eating, including choking or coughing
  • Severe reactions to medications
  • Symptoms of a urinary infection, like burning during urination or frequent urination
  • Sudden or significant changes in symptoms
  • Increased pain or discomfort

Questions to Ask Your Provider

If you are experiencing symptoms of Parkinson’s disease or have been diagnosed, important questions to ask your healthcare provider include:

  • How do Parkinson’s disease symptoms typically progress?
  • How frequently should I schedule medical appointments or see specialists?
  • What treatment options are available for managing Parkinson’s disease?

A Quick Review

Parkinson’s disease is a progressive neurodegenerative disorder that mainly affects movement and motor skills. The four cardinal symptoms are postural instability, slow or interrupted movements, rigidity, and tremors.

This disorder can also lead to significant challenges in walking, bodily function control, sleep quality, and mental health. Prompt medical attention and appropriate treatment are important to manage symptoms and maintain quality of life.

FAQs.

1. What is life expectancy with Parkinson's disease?
The average life expectancy of someone with Parkinson’s disease is similar to that of the general population. However, the disorder significantly impacts quality of life and can cause disability within 10 years of diagnosis.

2. What foods should you avoid with Parkinson's disease?
A diet rich in plant-based, whole foods may help manage Parkinson's symptoms. It is often recommended to avoid hard-to-chew foods like tough meats and raw vegetables, as well as high-sodium foods that could elevate blood pressure and worsen symptoms.

3. What is the finger test for Parkinson's disease?
The finger test assesses bradykinesia. A healthcare provider will ask you to rapidly touch your index finger to your thumb, then spread the fingers apart, repeating the movement with both hands to observe speed and coordination.