, according to the results of a new study.
The findings suggested that dementia occurs earlier in homeless individuals, and that these patients could benefit from proactive screening and housing interventions.
“Whether dementia caused the homelessness or homelessness caused the dementia, it’s a bidirectional relationship,” said lead author Richard G. Booth, PhD, RN, adjunct scientist at ICES (formerly Institute for Clinical Evaluative Sciences) and associate professor of nursing at Western University in London, Ontario, Canada.
The study was published in the April issue of The Lancet Public Health.
Dementia at Early Ages
The investigators used health administrative data from Ontario to compare the prevalence of dementia among homeless people with that among housed individuals in the general population and those living in low-income neighborhoods.
They included individuals aged 45 years or older on January 1, 2019, who visited hospital-based ambulatory care (such as emergency departments), were hospitalized, or visited a community health center in 2019. The researchers identified people as experiencing homelessness if they had one or more healthcare records with an indication of homelessness or unstable housing. The prevalence of dementia was ascertained as of December 31, 2019.
Included in the population-based, cross-sectional comparative analysis were 12,863 homeless people, 475,544 people in the low-income group, and 2,273,068 people in the general population group.
Dementia prevalence was 68.7 per 1000 individuals among the homeless population, 62.6 per 1000 in the low-income group, and 51.0 per 1000 in the general population group.
After adjustments for age, sex, geographical location of residence (urban vs rural), and health conditions associated with dementia, the prevalence ratio of dementia among homeless people was 1.71, compared with the low-income group, and 1.90, compared with the general population group.
Dementia also was detected in the 45- to 55-year age group among homeless people. This age is much earlier than the age at which doctors start screening their patients for cognitive decline (65 years).
“The study was not designed to define the causality but consider: If you have early-stage dementia and you are not intact enough to do basic functions of life, the likelihood of you becoming homeless is definitely increased, and vice versa. If you are homeless and suffer significant environmental and physical traumas just living on the street, you age much quicker, and you will experience geriatric symptoms such as dementia earlier in your life trajectory,” said Dr. Booth.
“The main takeaway here is that if you don’t have housing, bad things are going to happen in life.”
Public Health Problem
In an accompanying editorial, William J. Panenka, MD, associate professor of psychiatry at the University of British Columbia in Vancouver, British Columbia, Canada, and colleagues cited modifiable risk factors for dementia, including lower education, traumatic brain injury, substance use, smoking, mood disorders, and social isolation, many of which are disproportionately prevalent among homeless individuals.
“Ultimately, dementia could contribute to the cycle of homelessness, whereby housing instability increases the risk for brain impairment, and brain impairment makes breaking the cycle of homelessness progressively more challenging,” they wrote.
Dr. Panenka and colleagues also pointed out that the average age of homeless people is increasing. In the United States, it is now approximately 50 years. This fact underscores “the immediacy and gravity of the public health problem. A multifaceted approach that integrates healthcare, housing, and social services is needed to better understand and alleviate the health consequences of homelessness. A concerted effort at all levels is vital to inform future public health efforts and stem the tide of increasing morbidity, compromised function, and early mortality in homelessness,” they concluded.
Stephen Hwang, MD, director of the MAP Centre for Urban Health Solutions at St. Michael’s Hospital and Unity Health in Toronto, said that the study may underestimate the magnitude of the problem of dementia among homeless people.
“The methods used in this research study are very strong because they draw upon data for everyone living in the entire province of Ontario, and this is a very powerful way of looking at this challenging problem. The study probably underestimates the magnitude of the problem because to be diagnosed with dementia, patients have to have contact with healthcare providers that make that diagnosis. Often, people experiencing homelessness don’t have extensive contact with the healthcare system, and so their condition may go undiagnosed,” said Dr. Hwang.
A specialist in internal medicine, Dr. Hwang has provided healthcare for homeless people, and his research focuses on homelessness, housing, and health. He said that the findings from the Canadian study are applicable to the United States.
Forced clearances of homeless people and placing them in encampments, something that has been discussed in Florida, is unlikely to solve the problem, he said.
“The approach that has been shown to be beneficial is to engage with people and offer them housing and services that will allow them to exit homelessness without criminalizing the fact that they’re homeless. There really is no reason to think that this approach of forced clearances is going to help anyone.”
This study was supported by ICES (formerly the Institute for Clinical Evaluative Sciences), which is funded by the Ontario Ministry of Health and Ontario Ministry of Long-Term Care. Dr. Booth and Dr. Hwang reported no relevant financial relationships. Dr. Panenka reported receiving a research grant from the Canadian Institutes of Health Research.
A version of this article appeared on Medscape.com.