Parkinson’s disease is a progressive brain disorder that affects the nervous system, causing gradual loss of muscle control. According to Parkinson Canada, it occurs when cells that normally product dopamine, “a chemical that carries signals between the nerves in the brain,” die.
The symptoms of Parkinson’s disease present themselves slowly, and worsen as the condition progresses over time. Although they vary from person to person, the following are the six most common signs of the condition.
1. Tremors or Shaking
Tremors or shaking are among the most common motor symptoms of Parkinson’s disease. According to the Parkinson’s Disease Foundation, approximately 70 percent of people of people in the early stages of the disease will develop a tremor on one side of the body, typically in the hand or foot but sometimes in the jaw or face.
Shaking limbs can sometimes occur after engaging in exercise or if that particular area of the body has been previously injured, but when caused by Parkinson’s disease it will typically occur while the person is at rest and the muscles are relaxed.
2. Slowed Movement
As the disease progresses, movements that once occurred almost automatically may become slowed, making it challenging and time-consuming to do simple tasks such as buttoning a shirt or brushing one’s teeth.
This symptom, known as bradykinesia, may also make it difficult to walk, causing the affected individual to take shorter steps or drag their feet as they walk. Healthline says these symptoms are caused by “the impairment of the neurons that control movement.”
3. Rigid Muscles
Most people with Parkinson’s disease will develop some degree of muscle stiffness, particularly in the limbs, neck and trunk. This stiffness is known as rigidity, which WebMD defines as “the inability of the muscles to relax normally.”
Rigidity can decrease the body’s range of motion, causing discomfort and pain in the affected areas. One common sign of rigidity is a person’s inability to swing their arms while walking.
4. Changes in Writing
Micrographia, or small handwriting, is another common indicator of Parkinson’s disease, although it is subtler than some of the other motor symptoms. Writing can suddenly become more challenging; letters are written smaller and words appear crowded together on the page.
The Parkinson’s Disease Foundation says that bradykinesia, which makes it difficult to perform repetitive tasks, is what causes this to occur and is one of the most common ways it presents itself.
5. Impaired Posture and Balance
As a person with Parkinson’s disease loses some of the reflexes and coordination required to maintain an upright posture, they may become stooped or slouched over. This doesn’t happen overnight, however. Healthline says that “posture will change in small ways at first, and will gradually worsen.”
Parkinson’s disease may also affect a person’s balance, causing them to sway backwards when rising from a chair—known as retropulsion. Retropulsion may also make pivoting, turning or quick movements especially difficult.
6. Speech and Voice Changes
The muscle impairment caused by Parkinson’s disease can also affect how a person speaks. Speech problems often present themselves in several different ways, from slurring to speaking rapidly to hesitating before talking.
The voice becoming softer and more monotone are other common indicators of Parkinson’s disease. Northwest Parkinson’s Foundation says that this is frequently one of the first early warning signs of the disease, and is often noticed by friends and family before the patient becomes aware.