By Nicole MacKee
A map tracing the links between mental health disorders and somatic medical conditions should be a ‘wake-up call’ for both clinicians and patients, says a leading Australian psychiatry researcher.
Professor John McGrath, Director of the University of Queensland’s Centre for Mental Health and Conjoint Professor at the Queensland Brain Institute, Brisbane, recently led an international team of researchers in a Danish registry study of 5.9 million people born between 1900 and 2015.
The researchers assessed 10 broad types of mental disorders and 31 specific medical conditions. During follow up between 2000 and 2016, they found that people with mental disorders had a higher risk of developing a subsequent medical condition than those without mental disorders in 76 of the 90 mental disorder/medical condition pairings assessed.
The analysis, which was published in The New England Journal of Medicine, found that people with mental disorders had an almost 40% increased risk of developing a subsequent medical condition (median hazard ratio, 1.37). Hazard ratios varied from 0.82 for mental disorder and cancer to 3.62 for eating disorder and urogenital conditions.
Men with substance abuse disorders had a fourfold increased risk of gut or liver disorders, while women with anxiety disorders had a 50% increased risk of developing a heart condition or stroke.
Professor McGrath said that, on average, men with mental disorders lost about 10 years of life, and women lost about seven years.
‘We have seen in previous research that people with mental illnesses are not only dying from suicide but they have increased premature mortality due to everyday somatic conditions like heart attacks, diabetes, stroke, respiratory infections and lung disease,’ he said.
‘This map is a wake-up call for clinicians because we need to do better, we need to find better treatments and to reduce this premature mortality.’
Professor McGrath said the comprehensive map would reinforce lifestyle modification messages to patients.
A website exploring the medical risks associated with mental disorders has also been developed (nbepi.com/gmc).
In addition to increased risks, the researchers found some mental disorders to be protective. For example, patients with schizophrenia had a reduced risk of connective tissue disorders such as rheumatoid arthritis.
Professor McGrath said such findings provided important clues about underlying genetic or early-life risk factors that would hopefully stimulate further research.
N Engl J Med 2020; 382: 1721-1731.