Keypoints.doc: Difference between revisions

One of the hallmarks of aging is increased vulnerability where the apparent homeostatic point is closer to critical thresholds with increasing age because of decreased available physiologic reserves. That is a smaller challenge or perturbation can cause an older person to decompensate. Frailty is when the reserves are so depleted that trivial challenges produce decompensation.

One reason why the available reserves are decreased with age is that many are already being invoked to compensate for age-related changes just to maintain homeostasis. In the heart, reserves used to increase cardiac output for exercise or overload in the young are in use at rest in the old.

The development of a challenge has a dynamic in itself, interacting with the organism to potentially nip them in the bud. The “decompensation” is also dynamic from individual to individual, many individuals decompensate in the same way (ie., become confused or fall) no matter what the challenge.

The apparent homeostasis is also dynamic with small fluctuations occurring at all times and possible abilities to decrease vulnerability by increase the available physiologic reserves.