People with mental illness more likely to have multiple physical illnesses, study finds

People with severe mental illness (SMI) are nearly twice as likely to have multiple chronic physical illnesses, a large-scale review of research has found.

It is already well-established that people with SMI have a higher prevalence of several chronic physical health conditions, also known as multimorbidity. The aim of the review, carried out by Anglia Ruskin University, in partnership with Cambridge University, was to assess the strength of the association between SMI and physical multimorbidity.

The researchers analysed 19 different studies encompassing data from 194,123 psychiatric patients across the world, with 7,660,590 individuals in control groups. They found that psychiatric patients were 1.84 times more likely to report multimorbidity than the controls.

It is the first systematic review and meta-analysis, the researchers say, to collate the literature on SMI and physical multimorbidity. They note that long-term physical conditions and mental health problems “often co-occur, act synergistically and have negative effects on levels of disability, with longer hospital stays and increased costs and mortality.”

The physical conditions reported by the psychiatric patients in the study included metabolic diseases, hypertension, epilepsy, respiratory, vascular, kidney, and gastrointestinal diseases and cancer.

Poor clinical management leads to reduced life expectancy

The researchers note that physical health disparities “are observed across the entire spectrum of mental illnesses in low-income, middle-income and high-income countries.” They add: “The poor clinical management of physical comorbidity and multimorbidity in people with mental illnesses results in drastically reduced life expectancy and increases the personal, social and economic burden of mental illnesses across the lifespan.”

Their findings, the researchers say, “are in line with the growing evidence highlighting the increased risk of multiple physical conditions in people who suffer from severe mental health problems. Although these data are significant in and of themselves, they must be considered in light of the increasing number of mental health problems and the reduced and unequal healthcare offered to patients suffering from severe mental health problems.”

People with severe mental health conditions die on average 10–20 years earlier than the general population, and this is mostly due to preventable physical diseases, the researchers say, adding: “On the other hand, just a small fraction of people in need of mental health services have access to effective, affordable and quality mental healthcare, especially in low-income countries.”

As an example, the researchers say, 71% of those with psychosis worldwide do not receive mental health services.

Urgent need to find solutions

In order to address physical multimorbidity in those with SMI, the researchers write, there is an urgent need to find “integrated and multidisciplinary solutions which consider the complexity of care and the interaction of different health professionals and specialists across different types of care.”

Lee Smith, professor of public health at Anglia Ruskin University and lead author on the study, said: “Mental health underpins our individual and collective abilities to make decisions, build relationships, and shape the world we live in. It is evident from our research that individuals with severe mental illness are at a significantly higher risk of experiencing physical multimorbidity.

“This complex relationship between severe mental illness and physical multimorbidity has far-reaching implications, including decreased treatment compliance, increased risk of treatment failure, increased treatment costs, relapsing disease, worsening prognosis, and reduced life expectancy.

“Poor clinical management of physical comorbidities in people with mental disorders exacerbates the issue, leading to an increased burden on individuals, their communities, and healthcare systems.

“A holistic approach is urgently needed to improve the physical, mental, and social outcomes of individuals dealing with severe mental illness and physical multimorbidity.”