Homelessness is a major issue affecting many countries around the world. An estimated 552,830 people experienced homelessness in the United States in 2018 alone (1). Being homeless can have significant impacts on health and wellbeing, and is associated with higher rates of physical illness, mental disorders, substance abuse, and premature mortality (2). One important health outcome is lifespan—how long homeless people can expect to live compared to the general population. This article will examine what research shows about the lifespan of homeless individuals and the factors impacting it.
What is the average lifespan of a homeless person?
Several studies have investigated the lifespan of homeless populations. The research shows that on average, homeless people tend to have substantially shorter lifespans compared to the general population (3).
One influential study examined over 28,000 homeless adults in Boston over a 15-year period from 2003 to 2018 (4). It found that the average age at death for homeless individuals was 51 years for men and 43 years for women. This is compared to around 76 years for men and 81 years for women in the general US population (5). So homeless men died on average 25 years earlier than men in the general population, while homeless women died on average 38 years earlier.
Another large study in New York found that the average age at death for their homeless cohort was 63 years (6). The life expectancy gap may be narrower here compared to the Boston study, but it still showed homeless people were dying much younger than average.
Overall, research consistently shows that homelessness is associated with dramatically increased mortality and shortened lifespans. On average, most studies find that homeless people die between 30 to 40 years earlier than the general population.
Causes of premature death
What factors drive this substantially increased risk of premature mortality among the homeless? There are a range of physical and mental health issues that can negatively impact their lifespan.
Homeless individuals have higher rates of many chronic and acute physical health conditions that can contribute to earlier mortality if not properly treated (7). These include:
- Respiratory illnesses such as chronic obstructive pulmonary disease (COPD), pneumonia, and tuberculosis.
- Skin disorders including infections, ulcers, and abscesses.
- Gastrointestinal disease such as hepatitis.
- HIV/AIDS and other sexually transmitted infections.
- Malnutrition and poor diet.
The combination of exposure, crowded conditions in shelters, and inadequate health care means that homeless people are vulnerable to various infectious diseases and outbreaks which can be fatal without medication and treatment (8).
Chronic conditions like COPD, cancer, or heart disease often go undiagnosed or untreated, leading to premature death. Access barriers such as lack of health insurance, stigma, and transportation problems prevent proper medical care (9).
Mental illness is extremely prevalent among the homeless. Rates of serious disorders like schizophrenia, bipolar disorder, and major depression have been reported as high as 20-25% in some studies, compared to around 5% in the general population (10).
If not properly treated and managed, these conditions can significantly undermine health and survival. Mental illness is associated with higher risk of suicide, accidental death due to impairments in decision-making, vulnerability to assault or abuse, and lower ability to access healthcare (11).
Rates of alcohol and drug abuse are disproportionately high among the homeless compared to the general public. Estimates range from 25-50% for alcohol abuse and 10-20% for drug abuse (12).
Chronic alcoholism or drug abuse increases mortality risk through direct health impacts such as organ damage and overdose, or indirectly through impaired judgement, violence, accidents, and self-neglect (13).
Violence and trauma
Homeless individuals are at greater risk of violence victimization and psychological trauma. They may be subject to physical or sexual assault, abuse, or exploitation on the streets. One study found that over half of their homeless participants had experienced a violent attack since becoming homeless (14).
This psychological trauma and repeated victimization creates severe stress that can lead to anxiety, depression, PTSD, and other mental disorders. If not addressed, past traumas can contribute to the risk of premature mortality.
Factors that influence lifespan
While homelessness universally increases mortality risk, some groups tend to have relatively shorter or longer lifespans. Factors that can impact longevity include:
As noted earlier, research typically finds that homeless women die younger on average than homeless men. A review of five key studies found that the median age at death was 42 years for homeless females compared to 47 years for males (15).
Reasons for this gender disparity may include vulnerability to violence and sexual assault, healthcare needs related to menstruation and pregnancy, and higher rates of certain mental illnesses like major depression among homeless women (16).
Younger homeless adults aged 18 to 44 tend to have higher mortality rates than middle-aged and older homeless people. For example, one study found that death rates among homeless youth aged 18 to 24 were nearly eleven times higher than expected for the general population (17).
Younger people living on the streets lack survival skills and are more prone to substance abuse, risk taking, violence, accidents, and suicide. Older homeless adults may cope better with street life stresses.
Some studies have found differences in mortality rates between racial groups, but findings are mixed overall. One study found higher death rates among homeless whites compared to blacks and Hispanics (18). But another found that African Americans had the highest mortality rate out of all races (19).
More research is needed to clarify if race specifically contributes to shortened lifespan versus other socioeconomic factors common among minority groups like poverty, barriers to healthcare access, and discrimination.
Unsheltered versus sheltered homeless
People sleeping on the streets with no shelter at all tend to have higher mortality compared to homeless living in transitional housing or shelters (20). Shelters can provide protection from weather exposure, violence, and infectious disease. Street homelessness leaves individuals extremely vulnerable.
Geography and climate
Homeless populations in warmer climates like Florida tend to have longer lifespans compared to colder cities like Boston (21). Outdoor sleeping in harsh winters increases risk of hypothermia and frostbites. Hot southern regions have lower risks of cold exposure. Urban areas with high levels of sheltered homelessness and access to healthcare may also have higher survival rates.
Physical versus mental disorders
While physical illnesses reduce lifespan, mental disorders like schizophrenia and bipolar disorder have an even more severe impact. One study found that chronic psychiatric conditions accounted for the greatest fraction of premature mortality (22). Mental illness undermines judgement, motivation, and ability to care for oneself.
Duration of homelessness
Research shows that the longer an individual experiences homelessness, the greater their risk of premature death. One study found mortality rates doubled after one year of homelessness (23). Prolonged homelessness leads to deterioration of physical and mental health over time if living conditions do not improve.
In summary, homelessness substantially increases the risk of premature mortality. On average, homeless adults die 30 to 40 years earlier than the general population. Major causes include untreated physical illnesses, mental disorders, substance abuse, and violence. Groups at highest risk include women, younger adults, unsheltered homeless, and those with chronic mental disorders. Reducing homelessness through improved housing, healthcare access, and community support services could significantly extend the lifespans of this vulnerable population.