Tackling the health inequalities of people living with severe mental illness

Authors: Gerard Leavey, Michael Rosato, Finola Ferry, Rachel McCarter 

Date: February 2024

Research summary

This study examined the physical health disparities experienced by people with severe mental illnesses (SMIs), focusing on long-term illnesses, dental care, and eye health. The findings provide crucial evidence for policymakers, healthcare providers, and practitioners, highlighting the need for targeted interventions to improve health outcomes in this population. To maximise the impact of this research, the project team organised a symposium on SMIs, bringing together policymakers, practitioners, and service users to discuss the findings and explore practical solutions.

Background

Research has shown than people living with severe mental illnesses (SMIs) die up to 25 years earlier than the general population.

Despite two decades of evidence on health disparities related to SMIs, further research is needed to understand the risk factors and mechanisms driving poor health outcomes in this population. It is important to continually monitor their morbidity and mortality rates compared to the general population, to consider the ongoing impact of policy and public health initiatives.

People with SMI often face multiple barriers to healthcare, including fragmented services, diagnostic overshadowing, stigma, and social exclusion. These factors contribute to poorer health outcomes and lower engagement with essential health services.

Additionally, while evidence exists on the major physical health conditions affecting people with SMIs, less attention has been paid to other areas of health such as ophthalmology and dental treatment.

People with SMIs often face multiple barriers to healthcare, including fragmented services and discriminatory healthcare, as well as ‘overshadowing’ behaviour by professionals – the tendency to focus on their mental, rather than physical health. Additionally, factors such as social exclusion, stigma, low self-confidence, and cognitive deficits can undermine these individuals’ self-management and ability to engage with essential health services.

By using linked administrative data, this research provides a nuanced analysis of health disparities, examining health service use and outcomes for people with SMIs compared to the general population.

Data used

The researchers used linked data provided by the Northern Ireland Health and Social Care Business Services Organisation, which is managed and maintained by the Honest Broker Service.

The linked data consists of routinely collected electronically linked hospital administrative records, which the researchers used to define an initial study population of people normally resident in Northern Ireland and registered with a General Practitioner. It also includes:

• prescriptions data
• standard indicators of social deprivation
• dental records
• eye care records
• mortality data from the General Register Office
• demographic information.

Methods used

The researchers employed a range of approaches and statistical techniques:

Having multiple long-term health conditions and risk of death:

1. Analysed linked hospital administrative records (2010–2021) for patients aged 20 and above – 929,412 people, of whom 10,965 (1.3%) had an SMI diagnosis
2. Derived sex-specific age-standardised rates for seven chronic, life-limiting physical conditions
3. Examined the relationship between SMIs, social factors, and having multiple health conditions
4. Assessed how having an SMI affects people’s risk of death.

Dental services:

1. Linked GP, hospital, and dental data
2. Examined dental service use and treatments (extractions, fillings, crowns and x-rays) among the hospital population between January 2015 and November 2019 (with a sample size of 798,564).

Eye care:

1. Linked GP, hospital, and eye care data
2. Examined receipt of any eye tests from Health and Social Care, and (based on eligibility recorded for a sight test) any glaucoma, diabetes, and blindness
3. Examined the association of SMIs with each of the dental and eye care-related outcomes, controlling for sex, age, marital status, locale of residence, and area level deprivation.

Research findings

Having multiple long-term health conditions and risk of death:

• People with an SMI diagnosis were more likely to be living in socially deprived and urban neighbourhoods, and to have multiple physical health problems
• Although SMI patients were significantly more likely to be in contact with hospital services at younger ages and for all conditions, they were twice as likely to die early.

Dental services:

• People with SMI were less likely to be given fillings and x-rays as part of their dental service use, and instead experienced higher levels of extractions
• Older SMI patients were less likely to have received any of the four dental treatments than younger SMI patients - this may be explained by the likelihood of having significantly fewer teeth.

Eye care:

• Those with SMI were more likely to have an eye test, as well as be recorded as having diabetes
• However, they were less likely to be diagnosed with glaucoma. People with SMI were also less likely to have had an eye test in the older age groups, which may explain these lower rates of glaucoma.

Research impact

The researchers established a Community Advisory Board to ensure that this research was responsive to the needs of people with lived experience and facilitate optimum impact with policy and practice. Stakeholders included professionals from the Public Health Agency, Northern Ireland Department of Health, the Royal College of Psychiatry, and community-based mental health organisations (Inspire Wellbeing, Praxiscare, Mindwise and Action Mental Health).

The steering group helped inform research questions, interpret findings, and achieve policy impact. For example:

• Members clarified responsibility for the monitoring of the dental care of people with SMIs
• It contributed to the development of a new Client Management System, which could include reminders in care plans
• Plans were made to organise a psychoeducational workshop for professionals about the complex needs of patients with SMIs, including hygiene and self-care.

This study has provided evidence for policymakers, healthcare commissioners, and service providers across mental health, physical health, dentistry, and eye care, informing efficient resource allocation. The study findings are also useful to academics, service users, and carers, and can inform research across the UK and internationally.

Findings were shared through:

• Two Data Insights, presenting the research in accessible and useful forms for government and voluntary and community groups
• Peer-reviewed papers targeted at social policy, epidemiology, and mental health journals
• A symposium about SMIs for service providers, patients, policymakers, and voluntary and community groups.

Furthermore, the findings helped secure funding for CHOICE (Challenging Health Outcomes - Integrating Care Environments), a £2.2M social prescribing project in Northern Ireland. Co-designed with people who have lived experience, CHOICE aims to improve health and social outcomes for those living with SMI. This project is part of the Tackling Inequalities initiative, funded by the Arts & Humanities Research Council (UKRI).

Research outputs

Publications and reports

McCarter, R., Rosato, M., Thampi, A., Barr, R., Leavey, G. (2023). Physical health disparities and severe mental illness: A longitudinal comparative cohort study using hospital data in Northern Ireland. European Psychiatry, 66(1), e70, 1–8 . https://doi.org/10.1192/j.eurpsy.2023.2441

Ferry, F., Rosato, M., & Leavey, G. (2024). Mind the gap: an administrative data analysis of dental treatment outcomes and severe mental illness. Journal of Mental Health, 33(4), 474-480. DOI: 10.1080/09638237.2022.2069722

Ferry F, Rosato M, Leavey G. (2023). Severe mental illness and ophthalmic health: A linked administrative data study. PLoS One. 18(6):e0286860. doi: 10.1371/journal.pone.0286860.

Data Insights

Physical health disparities and mortality among people with severe mental illness in Northern Ireland (July 2024).

Mind the gap: an administrative data analysis of dental treatment outcomes and severe mental illness (January 2023).

Involvement events

Symposium about SMI and CHOICE Research Project: Challenging Health Outcomes - Integrating Care Environments.

Presentations

March 2023: symposium about SMI and CHOICE Research Project: Challenging Health Outcomes/Integrating Care Environments.

May 2024: Presentation by Professor Leavey to the NI Protect Life 2 Strategy Steering Group chaired by the Chief Medical Officer (Professor Sir Michael McBride).

June 2024: Public Health Agency – Mental Health Strategy Committee presentation by Professor Leavey on CHOICE and UK Public Mental Health Network.

September 2022: oral and poster (Life-limiting conditions and mortality associated with service use differences between people with severe mental illness and the general hospital population in NI) presentations at the International Population Data Linkage Network conference, Edinburgh.

Acknowledgements

The authors would like to acknowledge the help provided by the staff of the Honest Broker Service (HBS) within the Business Services Organisation Northern Ireland (BSO). The HBS is funded by the BSO and the Department of Health, Social Services and Public Safety for Northern Ireland (DHSSPSNI). The authors alone are responsible for the interpretation of the data and any views or opinions presented are solely those of the author and do not necessarily represent those of the BSO. The authors acknowledge the help provided by the steering committee members and the Community Advisory Board of CHOICE.