Parkinson's disease: Encyclopedia II - Parkinson's disease - Symptoms

Parkinson's disease - Symptoms

Parkinson's disease - Cardinal symptoms

Symptoms may vary among patients, and additionally may vary greatly over time in a single patient. However, the cardinal symptoms are:

• tremor (while this is the best known symptom, it is not displayed by an estimated 30% of patients with little perceptible tremor; these are classified as rigid-akinetic. The classical Parkinsonian tremor is 4-7Hz, often unilateral, decreased by supination and pronation, and responsive to dopaminergics and anticholinergics. In addition, tremors of the chin and lips tend to be Parkinsonian where tremors of the whole head suggest essential tremor.),
• rigidity (increased tone or stiffness in the muscles),
• bradykinesia (slowness of movement) and akinesia (lack of spontaneous movement),
• postural instability (failing balance, walking problems)

(The mnemonic TRAP (Tremor; Rigidity; Akinesia/bradykinesia; Postural instability) can be used to remember these symptoms.)

Parkinson's disease - Additional psychological and cognitive symptoms

These additional signs and symptoms are also commonly associated with Parkinson's Disease:

• depression: occurs in 40-70% of cases; 20% of depression cases are major depressive disorder; severity and persistance of depression is positively associated with executive dysfunction and dementia;
• anxiety or panic attacks
  Note: 70% of individuals with parkinson's disease diagnosed with pre-existing depression go on to develop anxiety; 90% of parkinson's disease patients with pre-existing anxiety subsequently develop depression);
• executive dysfunction, characterized by difficulties in: differential allocation of attention, impulse control, set shifting, prioritizing, evaluating the salience of ambient data, interpeting social cues, and subjective time awareness. This complex is present to some degree in most parkinson's patients; it may progress to:
• dementia: a later development in approximately 20-40% of all patients, typically starting with slowing of thought and progressing to difficulties with abstract thought, memory, and behavioral regulation.
• memory loss; procedural memory is more impaired than declarative memory. Prompting elicits improved recall.
• apathy or abulia: abulia translates from Greek as the absence or negative of will; apathy is an absence of feeling or desire
• altered sexual function: characterized by profound impairment of sexual arousal, behavior, orgasm, and drive is found in mid and late parkinson disease. Current data addresses male sexual function almost exclusively.
• sleep disturbances: including daytime somnolence; initial, intermediate, and terminal insomnia; disturbances in REM sleep, disturbingly vivid dreams, and REM Sleep Disorder, characterized by acting out of dream content;
• slowed reaction time; both voluntary and involuntary motor responses are significantly slowed.

Parkinson's disease - Additional sensory symptoms

• impaired visual contrast sensitivity, spatial reasoning, colour discrimination, convergence insufficiency (characterized by double vision) and oculomotor control
• dizziness
• impaired proprioception (the awareness of bodily position in three-dimensional space)
• loss of sense of smell (anosmia),
• pain

Parkinson's disease - Additional physical symptoms

• "freezing", a near-total inability to move, a state which can persist for minutes or hours;
• speech-language problems (hypophonia, loss of prosody in speech production and in reception of speech [[13]], and indistinct articulation; vocal cords can also be affected, causing monotonous, whispery, soft speech qualities);
• stooped or flexed posture,
• dydiadokinesia, or the inability to perform rapidly alternating, symmetrical hand movements;
• fatigue (up to 50% of cases);
• oily skin and seborrheic dermatitis;
• difficulty in swallowing;
• masked faces (a mask-like face also known as hypomimia), with infrequent blinking(http://jnnp.bmjjournals.com/cgi/content/full/64/3/320);
• drooling;
• micrographia (small, cramped handwriting);
• impaired fine motor dexterity and coordination;
• impaired gross motor coordination;
• loss of accessory movement, noted as decreased arm swing when walking
• difficulty rolling in bed or rising from a seated position;
• turning "en bloc", rigidly;
• gait characterized by slowness, and reduced amplitude in three dimension. The more-effected foot may drag, or be arched and curled on itself; also festination, characterized by small, rapid, stutter-steps forward, with a forward imbalance
• urinary incontinence, typically in later disease progression
• constipation, severe enough to endanger comfort and even health

Parkinson's disease - Other notes

Symptoms usually only begin to appear after about 80% of the dopamine in the brain has been lost. More recent data based on PET scans suggests that symptoms may occur when 50-60% of dopaminergic neurons are lost. The level of dopamine will continue to fall slowly over time, with an attendant worsening of symptoms.

It is an incapacitating disease, disturbing important human functions and ultimately substantially reducing quality of life. As in many neurologic diseases, psychological complications are often extremely serious and require the patient's family members and relatives to pay keen attention to the emotional fragility that usually follows the emergence of the disease; indeed, the depression which often results is seen by many as one of the worst aspects of the disease.

Fairly effective medication for the movement difficulties of Parkinson disease have been available for some time, but the neuropsychiatric aspects of the disease, especially depression and anxiety, are more recently characterized, less well understood, and often less adequately treated. As patients become more disabled, they become more dependent on care from others to perform all manner of tasks, from eating and bathing to monitoring and taking medication. Helping individuals with chronic disability and psychiatric comorbidity to maintain purposeful engagement with life takes a physical and emotional toll on caregivers, who may consequently experience illness and depression themselves.

Cases of PD are reported at all ages, though it is quite rare in people younger than 30 and the average age at which symptoms begin is 58-60; the risk of developing it substantially increases with age. It occurs in all parts of the world, but appears to be more common in people of European ancestry than in those of African ancestry. Those of East Asian ancestry have an intermediate risk. It is more common in rural than urban areas and men are affected slightly more often than women.

Adapted from the Wikipedia article "Symptoms", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki