They develop tremors and facial tics. . Parkinson's disease is a degenerative disease of the nervous system that generally affects both men and women who are more than 40 years old. The disease develops slowly over time and is associated with trembling of the arms and legs, stiffness and rigidity of the muscles and slowness of movement. A third of Parkinson's suffers also develop senile dementia. Parkinson's sufferers eventually die from secondary complications such as pneumonia, urinary tract infection, pressure sores, septicemia and stroke.
Symptoms vary from patient to patient, appear slowly and in no particular order.
Many years may pass before early symptoms progress to the point where they interfere with normal activities. It is thought that Parkinson's Disease is caused by a chemical imbalance in the co-ordination centre of the brain, known as the striatum. Parkinson's patients suffer from cell death in an area of the brain called the substantia nigra, which produces the chemical dopamine. As the cells die, less dopamine is produced and transported to the striatum, resulting in co-ordination problems. Later in the disease, cells in other portions of the brain and nervous system also degenerate.