GERIATRIC  [ back to Brain Injury 101 ]
TBI to an elderly person can be hard to detect, because of the assumption that old age is accompanied by increased forgetfulness, cognitive slowing, occasional disorientation, sometimes being at a loss for words, crankiness and insomnia. However, make no mistake that closed head injury is common in the elderly and is truly harmful to them, above and beyond the spontaneous deterioration of mental capacities associated with advanced age. 

Certain physical peculiarities of the elderly make them more susceptible to TBI. The elderly are more prone to fall, because of decreases in eyesight, balance and reaction time. Their skulls are thinner and more brittle than those of middle aged persons. Their brains are physically smaller due to atrophy, i.e. the progressive loss of brain cells over the lifespan due to effects of age, alcohol, first or second hand smoking, toxic exposure, decreased blood circulation, prior trauma, etc. Because their brains occupy less of the total intra-cranial volume, they have more room to accelerate and rebound during head trauma. This facilitates sudden acceleration/deceleration damage to their brains from closed head trauma. The shrinkage of the cerebrum causes a lengthening of the bridging veins that cross the dural membrane attaching the brain to the skull. These are veins that cause subdural hematomas when ruptured by head trauma. Thus the elderly are more likely to fall, more likely to sustain skull fracture and more likely to suffer subdural hematomas than younger persons. Subdural hematomas are much less dramatic and much less obvious than the epidural hematomas common in children that are accompanied by vomiting, lethargy and pupillary abnormalities. Subdural hematomas can cause gradual onset of dementia with no clear indicia of sudden brain damage.

Other factors can conceal TBI in the elderly. Older persons are more likely to live alone, so no one witnesses the fall onto the floor that they cannot remember or report. When an older person suffers head trauma in an accident that breaks their hip or leg, they must endure decreased mobility, loss of independence and depression. Frequently, the orthopedic trauma is blamed for all their  problems, when in reality a closed head injury to the brain is as much or more to blame for their decline.

We are living at a time of great sensitivity to Alzheimer's Disease, when early diagnosis can be made with MRI or PET scans showing damage to the hippocampus or memory center on both sides of the brain. Neuropsychological testing can also differentiate between dementia due to AD and dementia due to TBI. The course of AD and TBI is different. While Alzheimer's gets progressively worse and moves from loss of short term to loss of long term memory, the purely cognitive problems from TBI either get better over time or remain static.

Using neuroimaging, neuropsychological testing and applying knowledge about the course of illness, can tease apart a cognitive decline due to Alzheimer's or other dementia versus a cognitive decline due to TBI.

The expected course of the problem and the treatments are very different, so it is very important to make a correct differential diagnosis. For this reason, if an elderly person is known or suspected to have suffered head trauma, and displays cognitive decline, the possibility of TBI must be seriously entertained, and the person should be properly assessed by a neurologist and neuropsychologist for TBI vs. dementia. In some cases a person already diagnosed with mild dementia can suffer a TBI that seriously worsens his symptoms. To make matter still more complicated, a TBI in a susceptible person can trigger onset of Alzheimer's Disease. People known to be susceptible to Alzheimer's Disease from TBI are people with the APOE-e4 gene mutation. If the elderly victim of TBI was not exhibiting any signs or symptoms of dementia before the TBI, but experienced somewhat rapid onset of dementia thereafter, there could certainly be a causal link.

Why should we care if an elderly person sustains a TBI? This depends on whether you subscribe to the myths about growing old. One of these myths is that age necessarily brings about serious decline in cognitive abilities, physical mobility and the capacity to enjoy life. This is indeed a myth, because people are proving it wrong everyday by maintaining their minds and bodies in sharp, highly functional condition through physical and mental exercise well into their 70s, 80s and 90s. When an elderly person with intact faculties who is enjoying his life is rendered disabled by a TBI caused by someone else's negligence (such as driver who blew a stop sign), making a legal claim for damages is not just legitimate; it is imperative since the victim will need expensive medical and assitive care and therapies.