TBI+Prognosis

A traumatic brain (TBI) is a sudden alteration in brain functioning induced by an external trauma. [2] TBIs are the leading cause of death and disability in the youth of the United States(~50%), while approximately 50,000 people will die as a resu lt of a head injury. [17] [10] [2] [2]

**Types of TBI**

__**Closed:**__ a blunt force to the head -e.g: baby syndrome, motor vehicle accidents (MVA), falls, being hit with a blunt object to the head

__**Penetrating:**__ a foreign object enters the skull -e.g: firearms, shrapnel, being hit with a sharp object [2] [16]

How’d I get this TBI? O’Sullivan Says: 50% caused by motor vehicle accidents (MVA), falls 25%, violence 15%, and sports 10% [17] The CDC Says: 35% due to falls, 17% MVA [2] Falls are most common cause of TBI in elderly > 75 y/o and children 0-4 y/o [16]

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More good CDC Stats about TBI: (Breaks down age categories, also) [] [2]

Higher velocity or force traumas (MVA, falls, etc.) have higher hospital mortality and functional deficits -Violent MOI less likely to have poor community integration post hospital [15]

Patients will obviously present very differently with TBI symptoms and functional impairments. O’Sullivan suggests a patient can have any combination of neuromuscular, cognitive, visual, perceptual, behavioral, communication, and dysphagia deficits. [17] [17]

Poor GOS outcome, high hospital mortality, and low functional level after discharge: -Contributors: old age, high severity on Glasgow Coma Scale (GCS) or Injury Severity [15]

Link for Glasgow Outcome Scale

A loss of consciousness is a common occurrence with a TBI. Four main classifications of consciousness:


 * Stupor:** arousable with repeated, noxious stimuli
 * Coma:** un-arousable, not obeying commands, opening eyes, or verbalizing
 * Vegetative State:** consistent sleep-wake cycle and periods of alertness, but no ability to follow commands or verbalize
 * Persistent Vegetative State:** vegetative state > 1 month, no meaningful motor or cognitive function with absence of awareness of self or environment

__**Glasgow Coma Scale (GCS)**__
Asses: Level of consciousness after a head injury Components: best **eye, motor, and verbal responses** Uses: monitoring patients, determining deteriorating states, for traumatic and atraumatic head injuries
 * Indicator of severity of head trauma because of its relation to both outcomes of mortality and disability

Severity Scoring Classifications:

**14-15= Mild**
[17]
 * 15 is the max score you can have

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[]
 * Glasgow Coma Scale on the CDC’s website**

Severity commonly determined by score on Glasgow Coma Scale, coma duration, and length of Posttraumatic Amnesia. [17]

*GCS was better at predicting mortality with TBI*

 * [22]**

[18]

**Study comparing SMS and GCS**
Study used meta-analysis for comparing 5 different studies (yes, very small, but nonetheless interesting to look at this information, also did not include mild TBIs) 2= obeys commands 1= localizes pain 0= withdrawl to pain or less response
 * Simplified Motor Scale (SMS)** uses three components:

Statistically and clinically, there was **__no difference between the SMS and GCS scores of patients in predicting 3 things:__**
 * //1) Clinically significant brain injury//**
 * //2) Neurosurgical intervention//**
 * //3) Emergency tracheal intubation//**

SMS advantages: -Easier to remember -Can be used on intubated patients (no verbal component) -Much less complex than GCS -Near equivalent validity of GCS [22]

= Rancho Los Amigos Level of Cognitive Functioning = A scale that looks at cognitive and behavioral recovery in patients with TBI as they come out of a coma.

It is important to note that the longer a patient is in a coma, the less likely they are to achieve functional recovery. [17] Box 22.2 [17]
 * **I. No Response:** Patient appears to be in a deep sleep and is completely unresponsive to stimuli || **V. continued:** With structure, may be able to converse on a social automatic level for short periods of time. Verbalization is often inappropriate and confabulatory. Memory is severely impaired; often showsinappropriate us of objects; may perform previously learned tasks with structure but is unable to learn new information. ||
 * **II. Generalized Response:** Patient reacts inconsistently and nonpurposefully to stimuli in a specific manner. Responses are limited and often the same regardless of stimulus presented. Responses may be physiological changes, gross body movements and/or vocalization || **VI. Confused-Appropriate:** Patient shows goal-directed behavior but is dependent on external input or direction. Follows simple directions consistently and shows carryover for relearned tasks such as self-care. Responses may be incorrect due to memory problems, but they are appropriate to the situation. Past memories show more depth and detail than recent memory. ||
 * **III. Localized Response:** Patient reacts specifically but inconsistently to stimuli. Responses are directly related to the type of stimulus presented. May follow simple commands such as closing eyes or squeezing hand in an inconsistent, delayed manner. || **VII. Automatic-Appropriate:** Patient appears appropriate and oriented within the hospital and home settings; goes through daily routine automatically, but frequently robotlike. Patient shows minimal to no confusion and has shallow recall of activities. Shows carryover for new learning but at a decreased rate. With structure is able to initiate social or recreational activities; judgement remains impaired. ||
 * **IV. Confused-Agitated Patient:** is in a heightened state of activity. Behavior is bizarre and nonpurposeful relative to immediate environment. Does not discriminate among persons or objects; is unable to cooperate directly with treatment efforts. Verbalizations frequently are incoherentand/or inappropriate to the environment; confabulation may be present. Gross attention to environment is very brief; selective attention is often nonexistent. Patient lacks short and long term recall. || **VIII. Purposeful-Appropriate:** Patient is able to recall and integrate past and recent events and is aware of and responsive to environment. Shows carryover for new learning and needs no supervision once activities are learned. May continue to show a decreased ability relative to premorbid abilities, abstract reasoning, tolerance for stress, and judgement in emergencies or unusual circumstances. ||
 * **V. Confused-Inappropriate:** Patient is able to respond to simple commands fairly consistently. However, with increased complexity of commands or lack of any external structure, responses are nonpurposeful, random, or fragmented. Demonstrates gross attention to the environment but is highly distractible and lack ability to focus attention on a specific task. ||  ||

‍Anticipated Goals and Expected Outcomes for Levels I, II, and III:‍
-Physical function and level of alertness are increased. -Risk of impairment is reduced. -Motor control is improved. -Effects of tone are managed. -Improved postural control. -Increased tolerance for activities and positions.

Inability to move at levels I, II, and III can cause contractures, pneumonia, and DVT. Proper positioning is crucial in preventing any skin breakdowns and contractures. [17]

Table 22.7 [17]

Anticipated Goals and Expected Outcomes for Level IV:
-Patient’s endurance is improved. -Joint mobility and integrity are maintained. -Risk of secondary impairments is reduced. -Increased tolerance of activities.

The therapist should focus on endurance instead of progressing to more challenging things because the patient doens't have the capacity for new learning at this level. [17]

Anticipated Goals and Expected Outcomes for levels V and VI:
-Performance of functional mobility and ADL skills is increased. -Gait, mobility, and balance improved. -Motor and postural control are increased. -Risk of secondary impairments is reduced. -Increased strength and endurance. -Improved safety with functional mobility and ADL’s. [17]

Table 22.8 [17]



Anticipated Goals and Expected Outcomes for level VII and VIII:
-Improved safety for patient and family. -Increased ability to perform tasks related to ADL skills, community, work, and hobbies. -Improved functional mobility. -Improvement of balance, motor and postural control. -The patient will be able to self manage symptoms. -Increased strength and endurance. -Decreased level of supervision and assistance. [17]


 * Medical intervention includes: **
 * -Maintaining BP, O2 sats, trying to prevent further brain damage **
 * -CT of brain for severe to see extent of the damage **
 * -Radiograph of C-Spine and cranium **
 * -Can have surgery to remove hematomas (within 4 hours is best if **** surgery is indicated) **
 * [2]**


 * Secondary effect of TBI we want to avoid more adverse effects on the brain:**
 * Hypotension and hypoxia**
 * Hypoventilation and hypercapnia: cerebral vasodilation causing intracranial**
 * hypertension**

Pre-Hospital Endotracheal intubation (PHI) vs No-PHI and mortality rates amongst patients with moderate to severe TBI. No significant differences between the in-hospital rates between the two groups.

Multivariable logistic regression analysis determined PHI is independently associated with mortality (95% CI, P=0.004)

PHI (which occurs 2.6% of the time in this study) group nearly 5 times more likely to die compared to Non-PHI patients with mod-severe TBI. PHI patients are associated with longer hospital stays, greater time in the Intensive Care Unit (ICU) of the hospital. Compared to intubation immediately upon arrival at the ED, PHI patients were more likely to die (56.7% vs. 29.3%).


 * “The overall mortality for the study population was 14.4%. There was a marked difference noted in overall mortality (90.2% versus 12.4%, P < 0.001), with the PHI group being almost 65 times more likely to succumb to their injuries.”**


 * Rapid Sequence Intubation (RSI) à sedative + neuromuscular blocking drug administered by EMS**
 * -Better functional neurologic outcomes at 6 months compared to hospital intubation [1]**

[23]

**-Tells us about status of mesencephalic cisterns, midline shift, and presence or absence of local lesions**

 * Category || Definition ||
 * Diffuse injury I (no visible pathology) || No visible intracranial pathology seen on CT scan ||
 * Diffuse injury II || Cisterns are present with midline shift of 0-5mm and/or: lesion densities present; no high- or mixed-density lesion >25 cc; may include bone fragments and foreign bodies ||
 * Diffuse injury III (swelling) || Cisterns compressed or absent with midline shift 0-5mm, no high-or mixed-density lesion >25 cc ||
 * Diffuse injury IV || Midline shift >5mm, no high or mixed-density lesion >25 cc ||
 * Evacuated mass lesion || Any lesion surgically evacuated ||
 * Non-evacuated mass lesion || High or mixed-density lesion >25 cc, not surgically evacuated ||

http://surgvideo.surg.sunysb.edu/Volumes/ACSS+Jan+2011/ACSCD/tables/ch0719-t4.htm (For the Marshall Classification Table) [10]

“Obliteration of third ventricle or basal cisterns” on computed tomography was associated with the worst prognosis at 14 days. **Strongest predictor of 6 month mortality rate [18]**

Mild TBI symptoms:
headache, confusion, lightheadedness, dizziness, blurred vision or tired eyes, ringing in the ears, bad taste in the mouth, fatigue or lethargy, a change in sleep patterns, behavioral or mood changes, and trouble with memory, concentration, attention, or thinking. [2]

Mod to Severe TBI symptoms:
headache that gets worse or does not go away, repeated vomiting or nausea, convulsions or seizures, an inability to awaken from sleep, dilation of one or both pupils of the eyes, slurred speech, weakness or numbness in the extremities, loss of coordination, and increased confusion, restlessness, or agitation. [2]

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__Good Outcomes:__
-Epidural hematoma -Low to moderate (230 mg/dl) BAC had decreased mortality compared to no BAC or high BAC (BAC=Blood Alcohol Concentration) Why?: Alcohol is most likely associated with head trauma from a MVA, and maybe the alcohol allows the person to not tense up as much, resulting in a more flaccid body to prevent injury. (Like they say, the drunk driver usually is not hurt as bad as the person they hit) [15]
 * Neuroprotective effects of alcohol?
 * -Higher Glasgow Coma Score >6**

__Poorer Outcomes:__
-Low pH -ICP (Intracranial pressure) >20 -Pre-Existing Secondary Conditions (hypoxia, hypotension, hypothermia) -Intracranial mass lesion -Subarachnoid Hemorrhage (5x increase in poorer outcome) -Subdural Hematoma (increased mortality) [15]
 * -No light reflex of pupils**
 * -Marshall CT score of II with ANY shift**
 * -Marshall CT score of IV with >5mm shift (increased mortality)**
 * -Glasgow Coma Score <5-6**

=Prognostic Calculator: =

=Wear your [|helmet!]= Those individuals that are over 60 years old with a TBI have the highest rate of mortality of any age group. (5) That being said those that are over the age of 75 years old are three times as likely to die as those between the ages of 65 and 74 years old. However, there was a linear relationship between a decreasing score on the GCS and mortality rate even in the younger group. Among these older adults with TBI’s, those that fall into the categories of moderate or severe have higher mortality rates than those in the mild category.
 * AGE**

The GCS is reliable predictor of death in the younger age groups, those under 55 years old, (mortality rates increased in a linear fashion with the decrease in GCS), however it is much less of an accurate predictor in the older age groups due to the addition of confounding variables that affect their survival. The likelihood of co-morbidities increases with age including problems with the cardiovascular and urinary systems, cancer, diabetes, and other age related health problems. As a result, older individuals with TBI’s encounter more complications with recovery and necessitate more medical attention then younger individuals. This may explain part of the reason that there is a significant difference in mortality rates between the younger age groups and the older ones. An additional explanation for the difference would be the type of treatment that each age group receives. Those in the older group receive more conservative, lower intensity, treatment and have a higher percentage of DNR orders while in acute care. The younger groups receive more aggressive treatment in comparison. This more aggressive treatment may also contribute to the younger groups significantly better outcomes. (13) There is little research available pertaining to functional outcomes of the older group due to the predominant focus being on mortality outcomes. (25) [21]

The outcomes for pediatrics are a bit different. For one, behavior problems are an issue that must be kept a close eye on. Children with TBI’s are more likely to experience feelings of frustration and depression leading to behavior problems than those children who experience orthopedic injuries. Also there is some evidence that the poor behavior outcomes may be a direct result of the actual neurocognitive damage in addition to frustrations related to recovery.

About 20-40% of pediatrics suffering from TBI between the ages of 5 and 15 years old showed significant executive dysfunction within 1 year post injury.

A major factor in pediatric TBI prognosis is the family environment. Developmental changes, especially within the first year post injury, are highly influenced by the family environment and the intervention efforts need to be focused on making this environment as conducive to positive outcomes as possible. Behavior problems in children post TBI are a bit of a mixed bag in their presentation and are difficult to predict, especially since many may not show up until years later. However, being proactive to be watchful for behavior problem indicators as well as taking steps to create a conducive environment can have significant impact in decreasing the chances of behavior problems developing. (11)

Approximately 40% of all people suffering from TBI end up being able to return to work. Vocational rehabilitation programs that focus on specific tasks and social interactions have the highest success. However, TBI patients receiving any type of vocational rehabilitation have better outcomes then those who don’t in regards to their ability to return to work. (26)
 * ACTIVITIES OF DAILY LIFE**
 * Return to Work**

In a study on Vietnam War veterans who sustained penetrating head injuries compared to uninjured veterans, at 15-year follow-up, 56% of TBI veterans had returned to work compared to 82% of controls who had returned to work. Again, the more severe the TBI the lower the probability of ability to return to work. If the coma lasted under one hour the return to work percentage was 64%, between 1 to 24 hours, 50%, 1 to 6 days, 51%, 7 to 13 days, 36%, 14-28 days, 18%, and 29 days or longer, 6%. Additionally, within this population the longer the length of the coma the less those individuals earned for income. Time to return to work was also significantly and linearly related to TBI severity. Those individuals in the military with sustained TBI were discharged more often due to behavioral issues than the total group of discharged personnel. These issues included lack of motivation, misconduct, and a series of discipline problems. Discharge due to behavior issues was twice as likely in those with moderate or severe TBI than in the mild TBI group. Discharge resulting from drug or alcohol abuse was significantly higher in those with moderate or mild TBI than those with severe TBI. Medical disability discharge was 7.5 times higher in those with mild TBI than the discharge population without TBI, 25 times higher in those with moderate TBI, and 40 times higher in those with severe TBI. (24) Overall, risk of discharge was mostly related to injury severity, not the other types of discharge.

Sexual dysfunction is a significant problem in TBI patients. Of the patients that were sexually active prior to injury, over half of them report a decrease in the frequency of sexual activity, and about a third of them report a reduction in sex drive. Women were affected more than males when it came to sexual fantasy, arousal, behavior, and orgasm following TBI. That being said, even males scored significantly below the sampled control group based on the DISF-SR scale. Dissatisfaction in sexual functioning was reported in 29% of those surveyed with males reporting higher dissatisfaction then women. (20)
 * Sexual Function**

Sleep dysfunction is extremely prevalent among those with TBI with about 50% of participants reporting some level of dysfunction. This dysfunction has the ability to impact their recovery as well as their long term outcomes. These dysfunctions are significantly more prevalent than in the control group and in the community at large. The most prevalent types of sleep dysfunction are insomnia (29%), hypersomina (28%), and sleep apnea (25%). (12)
 * Sleep**

Factors that impact the ability of a TBI patient to return to work include both individual characteristics as well as the school support systems. Important individual characteristics include the student’s personality, feelings about their injury, personal goals, and ability to adjust. The concept of self plays a central and important role in the level of a TBI student’s participation and return to school. Those that personally struggle in dealing with their injury are more likely to have worse return to school participation related outcomes. TBI students must be able to accept their new identity, including the inevitable losses, as well as accept the opportunities and supports that are available to them to help them reengage in the school setting. School support systems are fairly uniform due to the well researched and documented successful recommendations in the literature. Therefore, it is the personal factors that are better predictors of success. Better outcomes are seen when the support systems focus on helping the student to reconstruct their lives.(14)
 * Return to School**

Social functioning assessments (SF-36 Physical Functioning and Social Functioning scales and SF-36 Perceived Health change) taken 6 months after injury revealed significant differences between the mild TBI group and the moderate/severe TBI group. The patients with moderate/severe TBI showed more dysfunction than did the patients with mild TBI. Additionally, within the mild TBI group, those with additional injuries fared worse than those with a TBI alone.
 * Social Functioning**

The ability of TBI patients to carry on conversation is also affected by injury. Conversations of TBI patients were considered to be significantly less interesting, appropriate, and rewarding. They required more effort than the conversations of the control subjects. In addition, they required more prompting and didn’t efficiently use the time during their turn to speak.

The higher severity of injury significantly correlates to a decrease in the number of friends (P<.04). (24) media type="youtube" key="NeAf-S_1GKI" height="315" width="420"[] ** Independent Living ** Return to independent living for those with a TBI was significantly lower than the trauma controls at 1 year follow up (76% vs. 93%). The longer a patient was in a coma following the injury the less likely that they will be able to return to independent living after 1 year (P<.001). If they were in a coma for less than one hour, 89% of them were able to return to independent living, 1 to 24 hours, 89%, 1 to 6 days, 74%, 7 to 13 days, 49%, 14 to 28 days, 55%, and more than or equal to 29 days, 23%. The more severe the injury the more dependent on parents the patient becomes (P<.02). The resulting conclusion of these findings was that one of the biggest changes in the lives of those who were previously living independently were forced to move back in with their parents. (24)

The leisure activities of those with TBI were significantly impaired compared to those with who do not (33%). (24)
 * Leisure **

(Temkin, Corrigan, Dikmen & Machamer, 2009) ** Overall, regardless of the severity and stage, those with TBI will experience some dysfunction in areas of their daily life including hygiene, walking, driving, and leisure. Those with a moderate or severe TBI may also have greater problems with finding and keeping a job, social functioning, and living independently. ** (24)

__Psychological Factors and Comorbidities Related to Prognosis of TBI__

__Depression:__
Many studies focusing on the relationship between depression and TBIs have lead to the discovery of mounds of information regarding the often correlated pair. Foundations for these studies are more than warranted as the prevalence of depression among TBI victims is nearly 3x that of the general population- 33% versus 8-10%. The vast majority of the information found in these studies directly relates to risk factors of developing depression following a TBI, and the most effective treatment plans for treating it.

The relationship between an obtained TBI and the future development of clinical depression is based on many well defined risk factors:
 * // **women** // have been shown to carry a higher risk for developing depression following a TBI than men, although they are less likely to suffer from recurring bouts of depression.


 * // **Men** //, although tending to be less likely to develop depression, are far more likely to develop a TBI in the first place. Middle aged men of low socioeconomic status have been shown to be the highest population risk of suffering a TBI. The most common modes of developing these TBI’s, many of which correlate with low socioeconomic status) are blunt force trauma, gunshot wounds, falls, heavy object falling on the head and motor vehicle accidents. Knowing this, it is easy to understand how alcoholism and drug abuse are each highly correlated both with the risk of obtaining a TBI and with developing depression following a TBI. [6] [28]




 * // **Past lifestyle patterns and behaviors** // consistently provide excellent predictors of patient behavior following a TBI. For example a history of alcohol abuse prior to obtaining a TBI is the best indicator that a patient will also struggle with alcohol abuse following the TBI. In the same way, previous history of depression is the best and most accurate indicator of developing depression following a TBI. Other elevating risk factors include residual cognitive disability, social aggression and motor disability. Hypertension, obesity and diabetes were all other common comorbidities assosciated with TBIs, but it is strongly suggested that lack of physical activity and depression contribute directly to these conditions. [6]

__**D**//**epression is itself a risk factor for developing other mental health disorders.**//__
__//**It has been clinically shown that being diagnosed with depression is a positive risk factor for developing...**//__ [29] [9]
 * Post Traumatic Stress Disorder
 * panic disorder
 * PTS (post traumatic seizures )
 * other generalized anxiety disorders.
 * personality disorders
 * psychosis

[29]

[9]

[28]

**__Treatment strategies for post TBI depression:__**

 * __//**Medication**//-__ In patients diagnosed with major clinical depression, Citalopram has been proven to be one of the most effective medications. Citalopram is an SSRI and when given over a 10 week period was shown to be very effective in improving patient’s symptoms of depression, even categorizing a percentage of the subjects as “in remission” following the Citalopram intervention. It is noted, however, that this form of therapy has only been shown to be effective on individuals diagnosed with major depressive disorder. Results on the effects of this treatment in those with mild or moderate depression were inconclusive. [19] [6]



//*note: It is important to educate patients on the importance of continuing a self motivated exercise program on their own, outside of physical therapy. A positive correlation has been shown to exist between the secession of exercising and the onset of depression.//
 * __//**Companionship**//:__It has been shown that individuals who have the availability of a confidant are less likely to develop depression than those who do not. Similarly, it has been concluded that there is an inverse relationship with number of years married and risk of developing depression [6].
 * __//**Peer Mentorship program**//__: Pairing TBI victims with non TBI peer models in a mentorship program also proved to be very successful in improving the quality of life for the TBI victims. Subjects who participated in this mentorship program self-reported a high level of satisfaction with the program, reporting that:
 * **__the program helped them improve in the areas of:__**
 * emotional functioning
 * community resources
 * acquired knowledge of TBI
 * “dealing with life”
 * Ultimately increased their amounts of happiness and quality of living
 * coping
 * **__the program also decreased/lessened:__**
 * the level of chaos in their home environment
 * alcohol abuse
 * emotional distress
 * desire for blame placemen [7]
 * __//**Exercise:**//__TBI victims who participate in exercise programs have been shown to have improved mood, balance awareness, self-esteem, and social participation. Types of effective exercise include 90 minutes /week or more of any of the following exercise regimens:
 * Tai chi
 * treadmill walking
 * balance retraining exercises
 * Structured aerobic exercise programs


 * //**__Goal Setting__:**// Research has shown that post TBI patients who participate in goal setting, set and reach more goals than those who don’t. Goal setting was shown to be related to better prognosis and to increased quality of life for patients who participated. This program was found to be especially effective in the areas of sleep, incontinence and leisure activities. When using goal setting as a form of therapy, it was found that goals were more effective when they were structured //**following a specific criterion:**//
 * goals were viewed as self-set
 * goals were paired with a nursing model of care for the patient
 * goals included patient’s friends and family in the goal making process
 * goals that were assigned or identified within a pre-existing structure improved task performance
 * goals were person-centered
 * goals utilized real-time inclusion of patient


 * It was also noted that patients were more likely to write generic goals focused particularly on reduction of impairment and activity limitations but were likely to ignore the personally relevant goals unique to an individual and involved in the reduction of handicap, and the resumption of social roles and personhood. [4]

__Dementia:__
It has long been suggested that a person’s chances of acquiring dementia, even early onset dementia is increased with a history of TBI. As it turns out, research is showing that there is in fact a //**significantly strong link between a history of moderate to severe TBIs ,“injuries of sufficient severity as to result in lack of consciousness or posttraumatic amnesia of longer than 24 hours”, and the prognosis of developing dementia.**// A meta analyses conducted over 15 case-control studies concluded that //**individuals who had obtained TBIs of this nature were 50% more likely to develop dementia than those who had not**//. Another prospective study done with 1,776 US Marine and Navy veterans, who had served in WWII, concluded that those who had experienced severe TBIs were over 4 times more likely to develop dementia than those who had not. [21]

__//APOE// ϵ4 allele and Dementia??__
Another piece of the TBI and dementia relationship puzzle which has yet to be put in place is how much the //APOE// ϵ4 allele contributes to the prognosis. Research on this is still inconclusive but it has been suggested that a person’s inheritance, or lack thereof, of this allele in combination with sustaining a severe TBI may alter their risk for developing dementia. Some studies have shown that people possessing the allele may have an increased risk for developing dementia by as much as 10 fold. However, other studies has previously stated, the research is yet ongoing and inconclusive. [8] [21]

__TBI and malignant brain tumors:__
One of the newest discoveries among TBI research, is the unfortunate link it holds to an individual’s increased risk of developing a malignant brain tumor. In studies that have been done around the world among adults 18 years and older of multiple ethnicities, it has been consistently proven that having a history of TBI resulted in a 4.67 fold increased risk of that individual developing a malignant neoplasm of the brain within a follow-up period of the TBI. The most tumors were discovered in a 1-3 year post TBI period but still more were discovered as far as 24 years following the TBI. There has been speculation that increased monitoring and imaging of the patient’s brain because of the acquired TBI is the link to the discovery of so many tumors. In light of this hypothesis, several more large scale retrospective studies were launched. As of 2011, the general consensus among researchers, although they cannot yet explain the pathology of this correlation, is that it does exist. It has also been found that in men, the risk is highest for developing meningiomas. [3]