People suffering from severe mental illnesses die 15 years earlier than the rest of the population. The underlying reasons for this mortality gap are complex. Cardiovascular disease seems to be at the heart of the matter here. As the mortality gap continues to expand, research by Osborn & colleagues regarding those with schizophrenia, psychosis and bipolar disorder has gone into evaluating the efficacy of different interventions to reduce cardiovascular risk.
In a randomised controlled trial, the Primrose intervention was tested against treatment as usual in general practice for people with severe mental illnesses (Osborn et al, 2018). The trial based in English primary care, looked at raised cholesterol as well as other modifiable cardiovascular disease risk factors. The research found that the different interventions are similar in terms of clinical effectiveness, but important questions are raised about the relative cost-effectiveness of treatments.
The Primrose intervention could prove to be a gateway to improve cardiovascular risk in patients with mental illness. The results of this study call for further research into possible interventions and the value that communities put into quality of life in financial terms. There is also a need to recognise that people with mental illness also carry a great burden of cardiovascular disease and should receive as much attention as the general population does, if not more.
Osborne and colleagues set out to investigate the cost-effectiveness and treatment outcomes for PRIMROSE: an intervention for reducing cholesterol and cardiovascular risk in patients with severe mental illness. They adopted a cluster randomised controlled trial methodology and opened the study up to all eligible GP practices in England. Practices were eligible if they had an available nurse or health-care assistant and at least 40 patients on their register with severe mental illness. From this, practices self-selected, and patients were randomly assigned to treatments.
Patients were eligible if they had severe mental illness, were between the age of 30 and 75, had high levels of cholesterol and presented with at least one more cardiovascular disease risk factor. Patients, health professionals and practitioners were informed of their treatment group, however researchers were masked to allocation to mitigate the chances of bias in the analysis. The provided statistics indicated minimal variance between socio-economic and physical/health statistics at the start of the trial. Due to health practitioners and nurses being aware of their allocated treatment group, it cannot be ruled out that participants were not treated equally, however there is no evidence provided to support either way.
The study considered a large range of secondary variables alongside the primary variable of lowered cholesterol. Secondary variables were collected at two intervals: at 6 months and at 12 months.
The Primrose intervention involved a trained primary care professional (Nurse or health practitioner) who conducted 12 weekly or fortnightly appointments with patients that aimed to instantiate behavioural changes (e.g. exercise, adherence to statin medication, cessation of smoking) that are thought to improve cardiovascular health outcomes. The control group was treatment as usual, however no details were provided about what this entailed.
The study had two main findings:
- There was no significant difference in cholesterol levels in patients with psychosis and obesity after 12 months of physical health intervention (behavioural change strategies). The behavioural change strategies were matched to risk factors of each individual
- There was some cost savings from inpatient admissions by using the physical health intervention.
- The mean total cholesterol did not differ at 12 months between the intervention and control group (treatment as usual)
- Mean cholesterol decreased over 12 months for both groups, but slightly more in the control group (not significant).
Cost effective savings
- Total healthcare costs in the intervention group was £895 cheaper per person than the control
- There was a saving from inpatient admission of £799 in the intervention group, when compared to the control.
This study suggests that there are possible cost saving benefits, mostly from reduced inpatient admissions in using behavioural strategies that help patients with psychosis and obesity to identify and take action on their personal risk factors for higher cholesterol and cardiovascular disorder.
While this trial showed no significant change in cholesterol levels over the 12 month period, further studies should explore these behavioural strategies to understand how preventive measures may improve the long term health (over 12 months) of individuals with psychosis and obesity. In the meantime, the cost-saving benefits that focus on behavioural changes should be explored by healthcare professionals seeking to reduce the bottleneck and long-term cost of treatment.
Strengths and limitations
- The study uses randomisation which limits selection bias and balances the groups with respect to any confounding variables (Suresh, 2011).
- Training a multidisciplinary team of nurses and healthcare assistants to deliver the intervention allows for broader expertise and ensures the intervention is delivered accurately.
- Well-balanced stratification of participant characteristics allows for an accurate comparison between treatment and control group. • Long follow up of 12 months provides information on efficacy and safety outcomes (Bennets et al., 2016).
- The authors place their findings in context, allowing for a better understanding of the outcomes. They also provide directions to improve future research.
- It would be interesting to know why training and non-attendance costs were not included in the economic analysis. Mitchell and Selmes (2007) found that the annual NHS cost of non-attended healthcare appointments was almost double among individuals with severe psychiatric conditions compared with the general population. Thus, it is possible that including costs of non-attendance would reduce the cost-effectiveness of the PRIMROSE intervention. As neither this nor attendance rates in the control group were reported, the author’s conclusion that the intervention is more economical is uncertain.
- Given that the majority of participants in the intervention and control groups were white, and England has a multicultural population, the applicability of the results for diverse ethnic groups is questionable.
- Although it is commendable that efforts were made to ensure protocol adherence by recording intervention sessions, adherence was not optimal. It would be useful to know how nurses and healthcare professionals deviated to minimise protocol adherence issues for future research.
Implications for practice
Although the total concentration of cholesterol did not differ between the Primrose intervention and the treatment-as-usual group, there is evidence to suggest that cardiovascular risk factors can be improved in patients with mental illness suggesting a lack of therapeutic nihilism.
The reduction in psychiatric admissions seen in the Primrose intervention group is also of interest and may suggest that these costs should be considered when measuring cost effectiveness of a physical health intervention. Further research should focus on designing additional interventions, which aim to improve the cardiovascular health of these patients.
Statement of interests
Thanks to the students from the University of Glasgow Global Mental Health MSc who wrote this blog.
University of Glasgow MSc Students
This blog has been written by a group of students on the University of Glasgow Global Mental Health MSc who took part in a blogging workshop led by The Mental Elf.
We regularly publish blogs written by individual students or groups of students studying at universities that subscribe to the National Elf Service. Contact us if you’d like to find out more about how this could work for your university.
Osborn, D et al. (2018) Clinical and cost-effectiveness of an intervention for reducing cholesterol and cardiovascular risk for people with severe mental illness in English primary care: a cluster randomised controlled trial. The Lancet Psychiatry, Volume 5, Issue 2, 145 – 154 https://doi.org/10.1016/S2215-0366(18)30007-5