From the Editor
Greetings from Ottawa. This morning, the Canadian Psychiatric Association’s 67th Annual Conference opens here. And the agenda looks great, and includes the release of the new Canadian guidelines for the treatment of schizophrenia.
It’s difficult not to feel upbeat, as people from coast to coast to coast gather to discuss new findings and new ideas on problems like refractory depression and chronic pain and, yes, schizophrenia. And this is a great time to be involved in mental health care – as stigma fades and societal recognition grows.
But how are we doing in terms of actual outcomes? This week, we look at a new British Journal of Psychiatry paper. Hayes et al. consider mortality for those with severe mental illness and the rest of us. Unfortunately, the authors find that the mortality gap has grown with time.
Ottawa: Host city of this year’s CPA Annual Conference
In this Reading, we review the paper and an editorial, and consider the larger context.
Illness and Mortality
“Mortality gap for people with bipolar disorder and schizophrenia: UK-based cohort study 2000–2014”
Joseph F. Hayes, Louise Marston, Kate Walters, Michael B. King, David P. J. Osborn
The British Journal of Psychiatry, September 2017
Death rates are increased in people with severe mental illness (SMI) relative to the general population, and this is reflected in the 10- to 20-year reduced life expectancy observed. This has been found in a number of longitudinal studies. However, it has been reported that the mortality gap has narrowed or plateaued since the mid-1990s in some countries. Since the turn of the millennium, a number of strategies aimed at reducing the mortality gap between people with SMI and the general population have been implemented in the UK. Similar strategies have been employed in other countries, including the USA, Canada, Australia and throughout Europe. Few studies cover this period. It is therefore timely to review all-cause and cause-specific mortality rates in individuals with bipolar disorder and schizophrenia relative to the general population. We used cardiovascular (CVD) mortality and suicide as exemplars of natural and unnatural causes of death that have been targets of mental health policy. Evidence suggests CVD is the leading cause of death in individuals with SMI. However, large representative longitudinal studies remain limited in number. In the UK a number of initiatives have been targeted at reducing CVD morbidity; to encourage earlier diagnosis, reduce risk factors and ensure effective treatment implementation. Suicide is the cause of death that is most elevated in individuals with bipolar disorder and schizophrenia compared with the general population. Up-to-date estimates of suicide rates are important markers of the success of psychiatric care. Self-harm is the major risk factor for suicide, with a large number of those dying by suicide having a history of self-harm. Self-harm is also a marker of quality of life and emotional distress in individuals with SMI. This study compares all-cause mortality, CVD death and CVD diagnosis, suicide and self-harm rates in people with bipolar disorder, and schizophrenia and a general population comparator group from 2000 to 2014.
So begins a paper by Hayes et al.
Here’s what they did:
- The data was drawn from UK primary care electronic medical records, covering 11 million people, from 2000 to 2014. The records include ICD-10 diagnoses.
- All individuals aged 16 and over were included if they ever had diagnoses of bipolar or schizophrenia. Exclusion criteria included diagnoses of depression and schizoaffective disorder.
- A comparator group was created with up to six people without diagnoses, but matched with age and gender.
- Outcomes considered cardiovascular mortality and suicide.
- Statistical analyses included Cox proportional hazards regressional analyses.
Here’s what they found:
- There were 17,314 people with bipolar disorder and 22,497 with schizophrenia. They were matched with 219,387 individuals without these mental disorders.
- Demographically: people tended to be in their early 40s (bipolar 42.79 years old; schizophrenia 42.51; comparison group 41.35); gender was mixed (bipolar 58.83% women; schizophrenia 37.78%; comparison group 46.51%).
- Deaths: bipolar 1,266 (7.30%), schizophrenia 2,061 (9.16%), comparison group 6,279 (2.86%). “Mortality was elevated in those with bipolar disorder (HR = 1.77) and schizophrenia (HR = 2.08) relative to the general population comparison group, after adjustment for age gender, calendar year, area-level deprivation and ethnicity…” Using statistical analysis, the authors found a drop then a rise in hazard ratios over years.
- “There was an elevated HR for CVD deaths in schizophrenia (HR = 1.39) after accounting for age, gender, calendar year, area-level deprivation, ethnicity and average number of visits to the physician during follow-up. Following additional adjustment for smoking, hypercholesterolemia, hypertension, BMI and diabetes CVD deaths were no longer elevated in people with schizophrenia relative to the general population…” The bipolar data was less clear. (See figures below.)
- “After accounting for age, gender, calendar year, area-level deprivation, ethnicity and average number of visits to the physician per year of follow-up, the suicide rate in those with bipolar disorder was 12.66 (95% CI 7.79–20.58) times that of the comparison group. The adjusted HR in the group with schizophrenia was 7.21 (95% CI 4.26–12.19).”
All-cause mortality rate and adjusted hazard ratios compared with the general population. In bipolar disorder and schizophrenia (2000–2014).
Mortality rates, per 100 person-years at-risk (PYAR) in (a) bipolar disorder and (b) schizophrenia groups. Adjusted hazard ratios (HRs) in (c) bipolar disorder and (d) schizophrenia groups.
In this cohort of over 17 000 people with bipolar disorder and over 22 000 with schizophrenia, we found decreasing rates of all-cause mortality for both disorders since 2000. However, the HRs for mortality relative to a matched general population comparison group increased from the mid-2000s. This suggests that the improvement in health in the general population is increasing more rapidly than in those with SMI, and health inequalities are growing. This is despite a greater focus on this problem at a national and international level, in specialist, primary care and public health settings.
The paper runs with an editorial by Siddiqi et al., “Closing the mortality gap for severe mental illness: are we going in the right direction?”
You can find it here:
They make several points:
- There is good news here: mortality has actually fallen for those with severe mental illness – it’s just that mortality fell more for the general population.
- There are various drivers of the disparity. They note, for example: “There has been a significant decrease in mortality for the UK general population during the past few decades, attributed largely to lifestyle changes, improvements in treatments, and initiatives for health promotion and prevention.Public health interventions (for example to reduce smoking and improve diet), however, appear to have largely failed to engage people with SMI.” Also: “Unfortunately, resources from bed closures have not been adequately re-invested in community mental health services.”
They close with a call for action:
We must continue to monitor mortality and make greater efforts to understand the causal mechanisms behind the increased risk of mortality for people with severe mental illness. We must also, based on what we know already, intervene with screening and targeted interventions.
A few thoughts:
- This is a good paper.
- The paper’s main finding is deeply troubling. Is it reproducible? The main finding of Nielsen et al. paper is similar: a growing life expectancy gap for those with schizophrenia and those without, by looking at Danish data from 1980 to 2010. (Curiously, that paper wasn’t referenced by Hayes et al.) You can find it here: http://www.schres-journal.com/article/S0920-9964(13)00117-5/fulltext.
- The Hayes et al. paper considers UK data (and is published in a UK journal). It’s likely that Canadian data would have yielded similar results. In a 2012 paper, Kurdyak et al. looked at cardiac outcomes in people with schizophrenia following an acute myocardial infarction. “Individuals with schizophrenia were 56% more likely to die within 30 days of discharge, but approximately 50% less likely to receive cardiac procedures or to see a cardiologist within 30 days of discharge.” You can find the paper here: http://www.sciencedirect.com/science/article/pii/S0920996412005269.
- There is the hope that our current interventions will help close this mortality gap over time. That said, it would seem more likely that our work has just began.
- Congratulations, by the way, to the authors of the new schizophrenia guidelines. And congratulations to Dr. Scott Patten, the editor of The Canadian Journal of Psychiatry, for publishing their papers in the September issue.
Reading of the Week. Every week I pick articles and papers from the world of Psychiatry.