Older age has been known to be a negative factor in recovery after traumatic brain injury. While there are several factors that may be involved in this association, such as pre-existing conditions or multiple medications that negatively impact the injury, a cellular explanation has also been proposed.
Mitochondria are critical to cell functioning because they are involved in producing energy and promoting growth. Mitochondrial dysfunction has long been associated with aging, and past research has shown that mitochondrial dysfunction in aging is much more evident when the brain has been injured than when it has not.
A recent study from the University of Kentucky has verified that mitochondrial dysfunction plays a role in negative recovery after traumatic brain injury in older patients. They found that mitochondria in the cells of the synapse of a neuron are particularly vulnerable after traumatic brain injury. The interaction between aging and injury creates a stress on mitochondria that can impair recovery, as well as increase mortality rates.
Gilmer LK, Ansari MA, Roberts KN, & Scheff SW. Age-related mitochondrial changes following traumatic brain injury. Journal of Neurotrauma. (February 2010).