Progression and Symptoms of Parkinson's Disease

Symptoms of Parkinson's disease are triggered by the progressive loss of dopamine in the brain. Typically, symptoms occur after eighty percent of the dopaminergic neurons in the brain have died.
 
To date, no know cure or treatment exists for halting the progression of PD. However, a wide range of therapies and medication can usually alleviate the symptoms of Parkinson's disease, which include rigidity, tremors, depression and Parkinson's dementia.

Symptoms of Parkinson's disease may vary considerably among patients. Not all patients will exhibit the main symptoms commonly associated with Parkinson's disease. For instance, as many as thirty percent of sufferers may not have tremor symptoms and, in some cases, the symptoms are so mild as to go undetected for several years. In addition, rates of progression and the severity of symptoms, once diagnosed, often differ significantly among patients. Lobes of the Brain


Early Symptoms of Parkinson's Disease

Early symptoms may include rigidity of limbs, fingers and shoulders and/or muscle stiffness and slight tremors in the hands, face and limbs. Initially, symptoms are likely to affect one side of the body only, often appearing in one hand, but then progressing slowly to both sides of the body. Onset and progression tend to be slow. In the majority of cases, symptoms appear gradually and sporadically and increase in severity, over a period of years.

Parkinson's Disease Symptoms Onset

Symptoms of Parkinson's disease rarely present in people under the age of 55, with early-onset of PD occurring in as few as five to ten percent of people under the age of fifty. Minor variations exist between the symptoms exhibited by early- and late-onset Parkinson's disease. The main difference tends to be the faster progression of the disease in younger age groups.

Main Symptoms of Parkinson's Disease

The four main symptoms of Parkinson's disease are:
  • involuntary tremors or trembling of the hands, face, jaw, arms and legs
  • rigidity or stiffness and muscle cramps of the neck, limbs and torso
  • slowness in initiating motor movements (bradykinesia)
  • poor balance, impaired co-ordination, postural instability, difficulty initiating movements, problems with walking, turning and talking, and poor manual dexterity involving simple tasks.

Other Symptoms of Parkinson's Disease

Parkinson's also produces a number of other symptoms, which include:
  • depression, anxiety and emotional problems
  • lack of motivation and mood swings
  • dementia, personality disorders
  • sleep disorders (such as insomnia and restless leg syndrome)
  • mask-like, expressionless face
  • shuffling gait and stooped posture
  • soft, monotone speech
  • excessive sweating
  • paralysis
  • inability to move (akinesia)
  • problems rolling over in bed
  • drooling, difficulty chewing and swallowing
  • small, "spidery" handwriting
  • constipation and/or urinary problems
  • decreased sense of smell.

Parkinson's Dementia

About 30 percent of Parkinson's patients develop dementia. It evolves slowly in the Parkinson's patient, with symptoms beginning to show about ten to fifteen years following the PD diagnosis. The presence of Lewy bodies is standard in Parkinson's dementia, but a majority of Parkinson's disease patients exhibiting dementia symptoms also have Alzheimer's disease.
 
Parkinson's dementia is caused by the dying off of specialized cells in the brain called neurotransmitters. The brain is divided into two hemispheres (the right controls the left side of the body, the left controls the right side of the body); dementia affects both hemispheres at the same time. Each of the hemispheres is divided into lobes. Each of these lobes control a different function. The symptoms exhibited by Parkinson's dementia depend on the lobe or lobes affected:
  • Frontal lobes: These are the most common lobes affected by dementia. The frontal lobes are responsible for movement, speech, problem solving and emotions. Symptoms include emotional instability, difficulty processing things happening in the immediate vicinity, balance and difficulty speaking.
  • Temporal lobes: Located just behind and below the frontal lobes the temporal lobes are responsible for memory, danger response, and sound and smell processing. The most common symptoms associated with Parkinson's dementia affecting the temporal lobes include memory loss and inability to retain new information.
  • Occipital lobes: The lobes process visual information, but are typically unaffected by dementia.
  • Parietal lobes: Dementia affecting the parietal lobes results in difficulty following directions and understanding speech. A person with Parkinson's dementia affecting the parietal lobes may also have difficulty determining distance and spatial relations.

The symptoms and treatment of Parkinson's disease were first mentioned over 5,000 years ago in the Ayurveda (the Indian Vedic system of holistic healthcare, based on healing the patient's whole personality, body, mind and spirit). The symptoms of Parkinson's disease were also touched upon in 2,500 BC, in the first ancient Chinese medical treatise entitled the Huang Di Nei Jing Su Wen.

Parkinson's Disease Prognosis

Parkinson's disease is rarely the direct cause of death; more commonly, people die from complications associated with PD rather than from the disease itself. The death rate from complications increases in severe cases of chronic Parkinson's where patients have suffered poor physical and mental health for several years. Common complications include pneumonia, sepsis (blood infection), stroke and other vascular diseases of the brain.
 
Life expectancy for people suffering from Parkinson's disease has improved markedly, in recent years, thanks largely to the increasing availability of more effective drugs and therapies for managing the symptoms of this distressing disease.
 
Resources

Hotton, G. & Chaudhuri, K.R. (2001).Parkinson's disease.

National Library of Medicine. (2004). Parkinson's disease. MedlinePlus Medical Encyclopedia.

National Institute of Neurological Disorders and Stroke. (updated 2005). Parkinson's disease: Hope through research [NIH Publication No. 94-139].

Paisan-Ruiz, C., Jain, S., Evans, E., Gilks, W., Simon, J., van der Berg, M., de Munian, A., et al. (2004, November 18). Cloning of the gene containing mutations that cause PARK8-linked Parkinson's disease. Neuron 44 (4), 595-600.

Parkinson's Disease Society. (2004, June 4). Will I die from Parkinson's?

Waseem, S. & Gwinn-Hardy, K. (2001, December). Pain in Parkinson's disease: Common yet seldom recognized syndrome is treatable. Postgraduate Medicine online 110(6).