English

Noun

1. The inability of a diseased or weakened organic system or organ to compensate for its deficiency, resulting in functional deterioration.
   • 1982, Pamela Martyn, "If You Guessed Cardiovascular Disease, Guess again," American Journal of Nursing, vol. 82, no. 8, p. 1239,

     Once it was determined that hyperthyroidism was the probable etiology of her cardiac decompensation, the next step was treatment of the underlying disease.

2. The deterioration of cognitive or emotional functionality in a person who is distressed or who suffers from a psychological disorder.
   • 1945, William C. Menninger, "The Mentally or Emotionally Handicapped Veteran," Annals of the American Academy of Political and Social Science, vol. 239 (May), p. 21,

     A varying percentage of our combat soldiers reach the limit of their endurance and must leave their foxholes, not for physical wounds but because of emotional decompensation.

Related terms

• decompensate

References

• Oxford English Dictionary, 2nd ed., 1989.
• Random House Webster's Unabridged Electronic Dictionary, 1987-1996.

Decompensation is the functional deterioration of a previously working structure or system. Decompensation may occur due to fatigue, stress, illness, or old age. When a system is "compensated", it is able to function despite stressors or defects. Decompensation describes an inability to compensate for these deficiencies. It is a general term commonly used in medicine to describe a variety of situations.

For example, cardiac decompensation may refer to the failure of the heart to maintain adequate blood circulation, after long-standing (previously compensated) vascular disease (see heart failure).

In psychiatry, decompensation is the deterioration of mental health in a patient with previously maintained psychiatric illness, leading to a diminished ability to think and carry on daily activities. This includes loss of memory, both long term and short.