Homeless people with mental illness have higher 30-year risk of serious cardiovascular disease, research finds
Homeless people with mental disease have a greater than double risk of developing serious or fatal cardiovascular disease over 30 years than people of the same age and gender with no risk factors for the disease, new research has found.
A homeless person with mental illness has a 24.5 per cent chance of having a heart attack, a fatal or non-fatal stroke or sudden cardiac death over 30 years, said Dr. Agnes Gozdzik, a research associate in the Center for Research in Inner City Health of St. Michael's Hospital.
That compares to a 10.1 per cent risk for the "ideal person" of the same age and gender who does not smoke or have diabetes, and who has normal blood pressure and body mass index, Dr. Gozdzik wrote in a study published today in the journal BMC Public Health.
She found the risk was significantly greater among men than women and was higher among those with a substance abuse problem.
Cardiovascular disease is a leading cause of death among homeless people, probably because they have a high rate of traditional risk factors such as smoking or undiagnosed or untreated hypertension, diabetes or high cholesterol, combined with the stress and low socio-economic status associated with homelessness. Dr. Gozdzik, who has a PhD in public health, said substance abuse and mental illness, which are both associated with an increased risk of cardiovascular disease, are also found at disproportionately high rates among homeless people compared to the general population.
"Many of the factors that we thought would be associated with the 30-year cardiovascular risk among homeless adults with mental illness were actually not significant, such as not having a family doctor or having a diagnosis of psychosis or having a higher need for mental health services," said Dr. Gozdzik. "However, if you are homeless and having a mental illness and are a male or have a substance use disorder, your risk of 30-year cardiovascular disease appears to be much higher even if you may not show the typical other predictors such as high BMI or hypertension, etc.. This is something that clinicians who work with this population should be aware of."
Dr. Gozdzik's study looked at 352 people in Toronto who were enrolled in the At Home/Chez Soi Project, a randomized trial of a Housing First initiative among homeless adults with mental illness. She said that while previous studies have looked at the 10-year risk of cardiovascular disease among the homeless population, she felt that was not a long enough period of time to take into account the impact of changed behavior, such as stopping smoking.
High rates of smoking are consistently reported in studies of both homeless and mentally ill populations. An estimated 73 to 80 per cent of homeless adults smoke. Tobacco companies have targeted people who are homeless in past marketing strategies, including distributing free cigarettes at homeless shelters. Focus group findings indicate that smoking is socially acceptable in homeless settings and many individuals smoke due to high levels of boredom and stress.
Similarly, people with mental illness are more than twice as likely to smoke cigarettes as the general population, with estimated prevalence rates ranging between 45 to 88 per cent among people with schizophrenia, 58 to 90 per cent among those with bipolar disorder and 37 to 73 per cent among people with a major depressive disorder, compared to a rate of about 20 per cent in the general population.
"Given that smoking represents a key modifiable behavior, primary care providers should be aware of these associations," Dr. Gozdzik said.
Among shelter users in Toronto, 40 per cent reported current drug problems, with marijuana, cocaine and opiates the three most frequently used substances. Cocaine in particular has been linked to a range of cardiovascular complications, including heart attack, arrhythmias, sudden death and cardiomyopathy.