A study of more than five million Canadians has found that having both physical and mental illness increases emergency department visits beyond what would be expected from simply tallying the health burden of each.
“When both are present, the sum of their impacts is greater than its parts,” says the study’s lead author Marc Simard, a biostatistician at the Institut National de Santé Publique du Québec.
The researchers looked at hospital patient diagnoses between 2012 and 2016, taken from a disease surveillance database that covers 98% of adults in Quebec, which has free, universal-access healthcare.
Armed with the information, they set about building a picture of how a mounting toll of physical and mental illness affects the likelihood people will make frequent visits to the emergency department, defined as three or more trips per year.
Patients were rated on the number of physical illnesses they had – for example rheumatoid arthritis, heart attack or high blood pressure – as well as the number and severity of mental disorders.
Schizophrenia, bipolar disorder and other psychotic disorders were graded as “serious” and all other mental disorders as “common”.
What the researchers found has major implications for the emergency care of people with mental health disorders.
In people without mental health issues, a rise in the number of physical illnesses from zero to four increased their risk of being a frequent ED attendee by just over 11%. But for people with a serious mental disorder, the same upping of physical illness raised their risk of frequent visits to more than 16%. That figure was nearly matched by people with “common” mental illness at just over 15%.
At first glance those percentages mightn’t seem big but, the authors write, “a small increase in risk for a large number of patients may have large public health effects”.
Those effects are measured in a linked editorial, lead-authored by Mark Sinyor, a psychiatrist and scientist at the Sunnybrook Health Sciences Centre in Toronto, Canada.
The editorial notes the study found that “synergy” between mental and physical disorders accounted for between 13% and 24% of all emergency department visits for people with a mental disorder, leading to 24,388 additional visits over 14 months.
“This would equate to more than $15 million in yearly excess health spending on emergency department visits alone,” the authors write.
Simard and colleagues offer a number of explanations for why this might be happening.
“People with mental disorders may engage in more unhealthy behaviours, such as tobacco use and poor dietary habits, and may have difficulty adhering to treatment,” they write.
Perhaps more worrying, they also say people with mental disorders can “receive less proactive treatment” for some diseases, noting that “other studies imply negative perceptions of people with mental disorders as noncompliant or difficult-to-treat patients”.
The editorial authors also point out that Western medicine is, perhaps belatedly, coming to grips with the deep links between mind and body.
“Just as we understand the heart and lungs to be separate but interdependent organ systems, the field of medicine is increasingly recognising brain and body as a single system,” they write.
A case in point, they say, is the interplay between depression and heart disease.
Depression can make people less likely to follow medical advice such as exercise, diet and smoking. But it can also have physical effects on inflammation and the endocrine system that damage blood vessel walls and make platelets stickier, increasing the risk of blood clots.
Those authors call for Canada to adopt a Mental Health Parity Act, similar to the US Mental Health Parity and Addiction Equity Act, which mandates that private health insurers do not discriminate against people with a mental illness, including substance misuse, and ensure equivalent coverage to physical illness.
The articles come as the Australian state of Victoria launches a Royal Commission into its overstretched mental health system. Emergency mental health care features prominently in its brief.
Last year the Australasian College for Emergency Medicine announced it would lobby government to reduce “access block” for emergency department mental health patients waiting for hospital beds. Those people comprised only 4% of patient load but made up 19% of those waiting for an inpatient bed. One mental health patient waited six days for a ward bed.
The editorial authors write out a clear prescription for change. We must, they write: “reduce the stigma of mental disorders that remains in medicine and… shift from viewing these disorders as an impediment to treatment of physical disorders, toward a justification for more intensive patient care efforts.”
The study and editorial appear in the Canadian Medical Association Journal.