Traumatic brain injury (TBI) is a serious public health problem in the United States. Each year, traumatic brain injuries contribute to a substantial number of deaths and cases of permanent disability. In 2010 2.5 million TBIs occurred either as an isolated injury or along with other injuries.

A TBI is caused by a bump, blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain. Not all blows or jolts to the head result in a TBI. The severity of a TBI may range from “mild,” i.e., a brief change in mental status or consciousness to “severe,” i.e., an extended period of unconsciousness or amnesia after the injury.

The Centers for Disease Control’s research and programs work to prevent TBI and help people better recognize, respond, and recover if a TBI occurs.

Overview

Traumatic brain injury (TBI) is a major cause of death and disability in the United States, contributing to about 30% of all injury deaths. Every day, 138 people in the United States die from injuries that include TBI.  Those who survive a TBI can face effects lasting a few days to disabilities which may last the rest of their lives.  Effects of TBI can include impaired thinking or memory, movement, sensation (e.g., vision or hearing), or emotional functioning (e.g., personality changes, depression).  These issues not only affect individuals but can have lasting effects on families and communities.

What is a TBI?

A TBI is caused by a bump, blow, or jolt to the head or a penetrating head injury that disrupts the normal function of the brain. Not all blows or jolts to the head result in a TBI. The severity of a TBI may range from “mild” (i.e., a brief change in mental status or consciousness) to “severe” (i.e., an extended period of unconsciousness or memory loss after the injury).  Most TBIs that occur each year are mild, commonly called concussions.

How big is the problem?

·        In 2010, about 2.5 million emergency department (ED) visits, hospitalizations, or deaths were associated with TBI—either alone or in combination with other injuries—in the United States. 

o   TBI contributed to the deaths of more than 50,000 people.

o   TBI was a diagnosis in more than 280,000 hospitalizations and 2.2 million ED visits.  These consisted of TBI alone or TBI in combination with other injuries.

·        Over the past decade (2001–2010), while rates of TBI-related ED visits increased by 70%, hospitalization rates only increased by 11% and death rates decreased by 7%. 

·        In 2009, an estimated 248,418 children (age 19 or younger) were treated in U.S. EDs for sports and recreation-related injuries that included a diagnosis of concussion or TBI.3

o   From 2001 to 2009, the rate of ED visits for sports and recreation-related injuries with a diagnosis of concussion or TBI, alone or in combination with other injuries, rose 57% among children (age 19 or younger).

What are the leading causes of TBI?

·        From 2006–2010, falls were the leading cause of TBI, accounting for 40% of all TBIs in the United States that resulted in an ED visit, hospitalization, or death.  Falls disproportionately affect the youngest and oldest age groups:

o   More than half (55%) of TBIs among children 0 to 14 years were caused by falls.               

o   More than two-thirds (81%) of TBIs in adults aged 65 and older are caused by falls.

·        Unintentional blunt trauma (e.g., being hit by an object) was the second leading cause of TBI, accounting for about 15% of TBIs in the United States for 2006–2010.

o   Close to a quarter (24%) of all TBIs in children less than 15 years of age were related to blunt trauma

·        Among all age groups, motor vehicle crashes were the third overall leading cause of TBI (14%).   When looking at just TBI-related deaths, motor vehicle crashes were the second leading cause of TBI-related deaths (26%) for 2006–2010.

·        About 10% of all TBIs are due to assaults. They accounted for 3% of TBIs in children less than 15 years of age and 1.4% of TBIs in adults 65 years and older for 2006–2010.  About 75% of all assaults associated with TBI occur in persons 15 to 44 years of age.

Risk factors for TBI

Among TBI-related deaths in 2006–2010:

·        Men were nearly three times as likely to die as women.

·        Rates were highest for persons 65 years and older.

·        The leading cause of TBI-related death varied by age.

o   Falls were the leading cause of death for persons 65 years or older.

o   Motor vehicle crashes were the leading cause for children and young adults ages 5-24 years.

o   Assaults were the leading cause for children ages 0-4.

Among non-fatal TBI-related injuries for 2006–2010:

·        Men had higher rates of TBI hospitalizations and ED visits than women.

·        Hospitalization rates were highest among persons aged 65 years and older.

·        Rates of ED visits were highest for children aged 0-4 years.

·        Falls were the leading cause of TBI-related ED visits for all but one age group.

o   Assaults were the leading cause of TBI-related ED visits for persons 15 to 24 years of age.

·        The leading cause of TBI-related hospitalizations varied by age:

o   Falls were the leading cause among children ages 0-14 and adults 45 years and older.

o   Motor vehicle crashes were the leading cause of hospitalizations for adolescents and persons ages 15-44 years.

Severe TBI

Each year, TBIs contribute to a substantial number of deaths and cases of permanent disability. In fact, TBI is a contributing factor to a third (30%) of all injury-related deaths in the United States.1 In 2010, approximately 2.5 million people sustained a traumatic brain injury. Individuals with more severe injuries are more likely to require hospitalization. 

Changes in the rates of TBI-related hospitalizations vary depending on age.  For persons 44 years of age and younger, TBI-related hospitalizations decreased between the periods of 2001–2002 and 2009–2010.  However, rates for age groups 45–64 years of age and 65 years and older increased between these time periods.  Rates in persons 45–64 years of age increased almost 25% from 60.1 to 79.4 per 100,000.  Rates of TBI-related hospitalizations in persons 65 years of age and older increased more than 50%, from 191.5 to 294.0 per 100,000 during the same period, largely due to a substantial increase (39%) between 2007–2008 and 2009–2010.  In contrast, rates of TBI-related hospitalizations in youth 5–14 years of age fell from 54.5 to 23.1 per 100,000, decreasing by more than 50% during this period.

A severe TBI not only impacts the life of an individual and their family, but it also has a large societal and economic toll. The estimated economic cost of TBI in 2010, including direct and indirect medical costs, is estimated to be approximately $76.5 billion. Additionally, the cost of fatal TBIs and TBIs requiring hospitalization, many of which are severe, account for approximately 90% of the total TBI medical costs.

TBI Classification Systems

TBI injury severity can be described using several different tools.

The Glasgow Coma Scale (GCS),5 a clinical tool designed to assess coma and impaired consciousness, is one of the most commonly used severity scoring systems. Persons with GCS scores of 3 to 8 are classified with a severe TBI, those with scores of 9 to 12 are classified with a moderate TBI, and those with scores of 13 to 15 are classified with a mild TBI.

Other classification systems include the Abbreviated Injury Scale (AIS), the Trauma Score, and the Abbreviated Trauma Score. Despite their limitations,6 these systems are crucial to understanding the clinical management and the likely outcomes of this injury as the prognosis for milder forms of TBIs is better than for moderate or severe TBIs.

Potential Effects of Severe TBI

A non-fatal severe TBI may result in an extended period of unconsciousness (coma) or amnesia after the injury. For individuals hospitalized after a TBI, almost half (43%) have a related disability one year after the injury.10 A TBI may lead to a wide range of short- or long-term issues affecting:

·        Cognitive Function (e.g., attention and memory)

·        Motor function (e.g., extremity weakness, impaired coordination and balance)

·        Sensation (e.g., hearing, vision, impaired perception and touch)

·        Emotion (e.g., depression, anxiety, aggression, impulse control, personality changes)

Approximately 5.3 million Americans are living with a TBI-related disability and the consequences of severe TBI can affect all aspects of an individual’s life.11 This can include relationships with family and friends, as well as their ability to work or be employed, do household tasks, drive, and/or participate in other activities of daily living.

Fast Facts

·        Falls are the leading cause of TBI and recent data shows that the number of fall-related TBIs among children aged 0-4 years and in older adults aged 75 years or older is increasing.

·        Among all age groups, motor vehicle crashes and traffic-related incidents result in the largest percentage of TBI-related deaths (31.8%).

·        People aged 65 years old and older have the highest rates of TBI-related hospitalizations and death.