It has been estimated that 1 out 3 adults over 65 years old falls down every year  (1). 

The growing ageing population worldwide and the changes in the physical activity patterns that we experience with age have led to the fact that fall accidents are currently a public health problem.  

The ageing process leads to multiple physiologic and morphological changes in our body, which can cause alterations in different functions and increase our fragility. Factors such as alterations in the visual or hearing functions, loss of muscle strength, balance disturbances or the use of some medications, among others, have strongly been linked to the risk of falling in the elderly. 

Unfortunately, many of these fall accidents cause an impact on the person’s head, leading to the diagnosis of Traumatic Brain Injury. 

What is a Traumatic Brain Injury? 

Traumatic Brain Injury (TBI) can be defined as an injury to the brain caused by an external force applied to the head.

Impacts, explosions or penetrating elements able to break through the skull are some of the agents which could cause a TBI. Moreover, depending on the causing agent’s characteristics and the acting forces’  biomechanical properties (speed, acceleration, direction, etc) the TBI and its outcomes will be different. 

In adults, the first cause of TBI is traffic accidents. However, in the population over 65 years old, 80% of the TBIs are caused by a fall accident (2).

In the case of fall accidents with an impact on the patients’ head, as we can see in the image, there are multiple forces which could cause a primary injury to the brain (skull fractures, contusions, axonal injuries etc): (a) linear forces, which make the head move forwards and backwards, hitting the back or front of the head; (b) rotational forces, which will make the head rotate to one side; (c) or impact deceleration forces, which occur when the head hits the ground.

Source : Blennow et al. 2016 (3)

After this primary injury, a secondary injury (brain hemorrhage, edema, increase in the intracranial pressure, etc) could be developed some hours or days after the accident. 

TBIs are usually classified as mild, moderate or severe, following the Glasgow Coma Scale (4), which is based on the following clinical elements:

Eye opening response	4 points       spontaneous  3 points       to sound 2 points      to pressure 1 point        none
Verbal response	5 points       oriented 4 points       confused  3 points       inappropriate responses (some words)  2 points       incomprehensible sounds or speech  1 point        no verbal response
Motor response	6 points       obeys commands  5 points       moves to painful stimuli  4 points       flex to withdraw from pain  3 points       abnormal (spastic) flexion, decorticate posture  2 points       extensor (rigid) response, decerebrate posture  1 point        no motor response

 

A score between 13 and 15 is considered as Mild TBI, from 9 to 12 as Moderate TBI and ≤8 as severe TBI.  In the elderly population, most TBI cases are classified as ‘’Mild’’ (5). However, it has been seen that an advanced age is a risk factor for clinical deterioration after TBI.

What are the consequences of TBI in the elderly population? 

The outcomes after TBI in the elderly population depend on multiple factors, such as the patients’ age, previous clinical history, comorbidities, injury severity, location of the injury, clinical management, etc. 

The most frequently found consequences are sensory, cognitive, motor and/or speech disturbances. Therefore, many of these patients become dependent for their daily life activities, which has a negative impact on their quality of life. Furthermore, in some cases, TBI can even lead to mortality. 

Multiple studies have shown that elderly patients suffer from worse outcomes after TBI, when compared to younger patients (6).

How could research help to reduce the impact of TBI in these patients’ quality of life? 

To date, elderly patients have been underrepresented in the TBI research field. However, the growing incidence and prevalence of TBI in the elderly have increased the interest for the study of this population among the scientific community. This could lead to many benefits for these patients and society.

At the moment, most of the used clinical guidelines and prognostic tools with this population are based in data obtained from younger patients. Therefore, many of the existing prognostic tools have shown to lose reliability with age. In the near future, new studies, specific for the population older than 65 years old, are necessary to create better prognostic tools with higher efficacy for this age group. In that way, we will be able to select the best clinical strategies to treat each of these patients and improve their quality of life.

References

1. Tinetti ME, Speechley M, Ginter SF. Risk factors for falls among elderly persons living in the community. N Engl J Med. 1988 Dec;319(26):1701–7. 
2. Depreitere B, Meyfroidt G, Roosen G, Ceuppens J, Grandas FG. Traumatic brain injury in the elderly: a significant phenomenon. Acta Neurochir Suppl. 2012;114:289–94. 
3. Blennow K, Brody DL, Kochanek PM, Levin H, McKee A, Ribbers GM, et al. Traumatic brain injuries. Nat Rev Dis Prim. 2016 Nov;2:16084. 
4. Teasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet (London, England). 1974 Jul;2(7872):81–4. 
5. Styrke J, Stålnacke B-M, Sojka P, Björnstig U. Traumatic brain injuries in a well-defined population: epidemiological aspects and  severity. J Neurotrauma. 2007 Sep;24(9):1425–36.
6. Mak CHK, Wong SKH, Wong GK, Ng S, Wang KKW, Lam PK, et al. Traumatic Brain Injury in the Elderly: Is it as Bad as we Think? Vol. 1, Current translational geriatrics and experimental gerontology reports. United States; 2012. p. 171–8.

 

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This article was sent by Rebeca Alejandra Gavrila Laic. Rebeca graduated from Physiotherapy in the University of Zaragoza and studied the master in Neuroscience at the Universidad Autónoma de Madrid. In 2018 she moved to Leuven (Belgium) to start her PhD at KU Leuven. She studies the effects of Traumatic Brain Injuries in elderly people. You can find her on LinkedIn and Twitter.