Parkinson’s disease is a disease in which the cells that normally produce the neurotransmitter dopamine die off, resulting in a loss of muscle control. It is a slow, progressive disorder of the central nervous system.
The four major symptoms are slowness of movement, muscular rigidity, resting tremor (trembling at rest or when not moving), and postural instability (shuffling, unbalanced walk that progresses into uncontrollable tiny, running steps to keep from falling). This disease usually begins as a slight tremor in one hand, arm, or leg. The tremor is at its peak during rest, improves with movement, and is completely absent during sleep. The tremor gets worse with fatigue and stress. In 50% to 80% of individuals with Parkinson’s disease, the tremor starts in one hand and resembles trying to roll a pill between the fingers; thus, it is called a “pill-rolling tremor.” The jaw, tongue, forehead, and eyelids may also tremble, but the voice is not shaky. Another early sign is a severe decrease in blinking of the eyes. As the disease progresses, there is more stiffness, weakness, and both sides of the body become involved, and the initial tremors may become less prominent. There may develop a shaking of the head, a mask-like expression on the face in which the eyes do not blink, and a rigid, bent-over posture that is permanent. Speech becomes difficult and slow, handwriting becomes small. Depression and dementia may occur. All daily activities become difficult.
Occurrence: 50,000 cases a year in the geriatric population in the United States, or one in 200 elderly. Men are more susceptible than women.