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Understanding the Link Between Brain Injury and Homelessness

Research shows homeless people experience brain injury at a higher rate.

jalisko/Adobe Stock
Source: jalisko/Adobe Stock

Homelessness is a tough issue to quantify and study. The most recent tally by the U.S. government estimates there are nearly 600,000 homeless people in the U.S. And if you add in homeless people in other developed nations, that number reaches more than 1 million.

Social scientists have dedicated decades of research to understanding how and why people become homeless, and how to help. Now a new systematic review sheds light on a possible contributing factor to homelessness.

Canadian public health researchers have documented a startling incidence of brain injuries among homeless people. In a meta-analysis published last December in The Lancet, researchers from British Columbia combined the data from 38 studies to better understand the connection between traumatic brain injuries and homelessness.

They found that more than 50 percent of homeless people have experienced a traumatic brain injury of some sort – more than double the rate in the general population. And approximately 22 percent of homeless people have experienced a moderate to severe traumatic brain injury; that is 10 times the prevalence in the general population.

A traumatic brain injury is caused by a sudden jolt or hit to the head. When this occurs, the brain smashes against the skull, which can lead to bruising, bleeding and tearing of the brain tissue.

Immediately after a brain injury, the person may feel confused or experience dizziness, blurry vision, headache or memory problems. But often the most serious symptoms occur after the initial injury, when the brain swells and pushes against the skull. This can reduce the flow of oxygen to brain tissue and lead to longer-term symptoms including headache, sensitivity to light and noise, hampered decision-making, cognitive difficulties and emotional instability. These longer-term symptoms can last for months or years and affect a person’s ability to work and care for themselves and others.

Due to the quality of the data available, the review authors were not able to determine definitively whether brain injuries increase the risk of homelessness or whether being homeless increases the risk of experiencing a brain injury. But they did find some data that shows most study participants experienced at least one brain injury before they became homeless.

They also found that homeless people were most likely to have sustained a brain injury due to an assault. And study participants who had traumatic brain injuries were more likely to report poor physical and mental health, thoughts about suicide, poor memory and more involvement with the criminal justice system.

The take-home message: Traumatic brain injuries may be a contributing factor to homelessness in developed countries. These injuries create serious obstacles and difficulties for the homeless population.