Key points
- People with severe mental illness develop physical illness sooner than the general population.
- Many people with severe mental illness have multiple chronic condition across their body system.
- Young women with mental illness experienced disproportionately poorer physical health outcomes.
Being diagnosed with a severe mental illness such as schizophrenia or bipolar disorder can reduce a person’s life expectancy by up to 20 years compared with the general population, University of Queensland researchers have found.
To investigate this problem, psychiatry registrar and UQ PhD candidate Dr Sean Halstead analysed 24 years of Queensland hospital data covering nearly 180,000 patients, finding people with severe mental illness developed serious physical diseases much sooner.
“Many people have assumed the shorter life expectancy associated with schizophrenia or bipolar disorder is mostly due to suicide, but much of the gap is actually driven by physical illnesses, many of which are preventable or treatable” Dr Halstead said.
“We need to stop thinking about schizophrenia and bipolar disorder as mental health conditions that exist in isolation.”
Researchers examined 11 major categories of physical illness including cardiovascular, respiratory, musculoskeletal, neurological, infectious and metabolic diseases.
Among the 30,000 people with severe mental illness, rates of physical disease were substantially higher, with many patients experiencing multiple chronic conditions affecting different systems.
“These physical conditions affect health across the entire body,” Dr Halstead said.
“Good treatment isn’t just managing the primary condition; it’s looking after the whole person and preventing complications.
“By the time physical conditions emerge, opportunities for prevention may already have been missed.”
The study found severe mental illness had its biggest impact on physical health in younger adults, particularly women under 25 who experienced disproportionately poorer physical health outcomes.
Psychiatrist, senior UQ researcher, and co-author Professor Dan Siskind said growing evidence suggests schizophrenia and bipolar disorder may have broader effects on the body than previously understood, but the relationship between severe mental illness and physical disease remains an evolving area of research.
“Evidence points to a combination of factors, including genetics, medication side effects, higher rates of smoking and alcohol use, challenges accessing healthcare, and the tendency for physical symptoms to be overlooked in people with severe mental illness,” he said.
“A person diagnosed with a mental illness at, say, age 20 may start medication that causes weight gain and, over time, develop diabetes, kidney disease, and an increased risk of stroke or heart attack.”
Dr Halstead said prompt treatment and regular physical health monitoring following a mental health diagnosis could help reduce the build-up of multiple chronic conditions.
“Doctors need to be thinking about physical health from the moment severe mental illness is diagnosed.”
Read the research published in Lancet Psychiatry.
Collaboration and acknowledgements
The research was conducted in collaboration with Metro South Addiction and Mental Health Service, Queensland Centre for Mental Health Research, Queensland Health Statistical Services Branch, King’s College London, University of Oxford, Charité – Universitätsmedizin Berlin, Karolinska Institutet, University of Sydney, University of Eastern Finland and Dalhousie University.
