People with a mental illness die on average about 10-15 years earlier than people without one. The evidence is probably strongest, as it often is, for schizophrenia – because that condition tends to get the most research funding. Ten years ago, Hennekens and colleagues showed that people with schizophrenia had mortality rates about twice as high as in the general population – and that the single biggest contributor to this premature death was heart disease. Numerous studies before and since agree that more than 50% of people with schizophrenia die from heart disease as compared to about 25% of the rest of the population. And this mortality gap is probably increasing.[2,3]
A substantial (10 years or more) reduction in life expectancy is also a fact of life for people with bipolar disorder, depression and learning disability.[4,5] And mortality rates are even higher in people with substance use disorders and anorexia nervosa. The natural (stigmatising) reaction to these figures is to suggest that suicide is the cause, but it isn’t. Suicide accounts for about 5-10% of deaths in people with mental illnesses. The vast majority of people with mental illness die from heart attacks, strokes and cancer like the rest of the humanity. So why is this?
What causes health inequalities?
Schizophrenia, like all mental illness, has many causes. So does heart disease. Just about everyone knows that heart attacks are related to a family history, poor diet, alcohol excess, smoking, a lack of exercise, hypertension and high cholesterol. And just about all these factors are more common in people with schizophrenia.[1,6] But there are also other factors, over and above those in the general population…
Additional genetic risk – Andreassen and colleagues have identified ten genetic loci that are associated with both schizophrenia and heart disease risk factors, mainly genes coding for triglyceride and lipoprotein levels but also waist-to-hip ratio, systolic blood pressure, and body mass index. In other words, many people with schizophrenia are at higher genetic risk of heart disease.
Medication (but especially the lack of it) – Many people assume antipsychotic drugs increase early deaths in schizophrenia, and they probably do increase the rate of sudden cardiac death but this is very, very rare. What people appreciate less is that antipsychotics and especially clozapine probably reduce overall mortality. In other words, if one has schizophrenia antipsychotics prolong life.
Probable discrimination in health services – In addition, it is increasingly clear that people with schizophrenia have difficulty accessing the usual health care services for physical illness. They are less likely to consult doctors, less likely to take part in health screening, and less likely to be investigated or treated in primary care. Even if they are seen, people with schizophrenia are less likely to be referred to, investigated or treated in secondary care.[9,10] To what extent these factors reflect self-stigma, a lack of self-care, medical service stigma, underfunding of mental health service funding and underfunding of research into causes and treatments is unclear but perhaps all apply.
What should we do about it?
The excess mortality in all mental illnesses demand a higher priority for research into the prevention and treatment of the causes of early death in the mentally ill. And yet, even though mental health is supposed to be a priority it gets about 10% of all NHS funding in the UK and only 5% of research funding. Thus, researchers, doctors, carers and patients should work together:
- For parity of mental and physical health in both service provision and research spend
- To try to reduce self- and medical-stigma of the mentally ill
- To promote healthy lifestyle interventions in people with schizophrenia and other conditions – preferably interventions that have been shown to work in those particular populations.
 Hennekens CH, Hennekens AR, Hollar D, Casey DE. Schizophrenia and increased risks of cardiovascular disease. Am Heart J. 2005 Dec;150(6):1115-21. http://www.ncbi.nlm.nih.gov/pubmed/16338246
 Brown S. Excess mortality of schizophrenia. A meta-analysis. Br J Psychiatry. 1997 Dec; 171:502-8. http://www.ncbi.nlm.nih.gov/pubmed/9519087
 Saha S, Chant D, McGrath J. A systematic review of mortality in schizophrenia: is the differential mortality gap worsening over time? Arch Gen Psychiatry. 2007 Oct;64(10):1123-31. http://www.ncbi.nlm.nih.gov/pubmed/17909124
 Chesney E, Goodwin GM, Fazel S. Risks of all-cause and suicide mortality in mental disorders: a meta-review. World Psychiatry. 2014 Jun;13(2):153-60. http://www.ncbi.nlm.nih.gov/pubmed/24890068
 Walker ER, McGee RE, Druss BG. Mortality in mental disorders and global disease burden implications: a systematic review and meta-analysis. JAMA Psychiatry. 2015 Apr;72(4):334-41. http://www.ncbi.nlm.nih.gov/pubmed/25671328
 Osborn DP, Hardoon S, Omar RZ, Holt RI, King M, Larsen J, Marston L, Morris RW, Nazareth I, Walters K, Petersen I. Cardiovascular risk prediction models for people with severe mental illness: results from the prediction and management of cardiovascular risk in people with severe mental illnesses (PRIMROSE) research program. JAMA Psychiatry. 2015 Feb;72(2):143-51. http://www.ncbi.nlm.nih.gov/pubmed/25536289
 Andreassen OA, et al. Improved detection of common variants associated with schizophrenia and bipolar disorder using pleiotropy-informed conditional false discovery rate. PLoS Genet. 2013 Apr;9(4):e1003455. doi: 10.1371/journal.pgen.1003455. http://www.ncbi.nlm.nih.gov/pubmed/23637625
 Tiihonen et al. 11-year follow-up of mortality in patients with schizophrenia: a population-based cohort study (FIN11 study). Lancet. 2009 Aug 22;374(9690):620-7. http://www.ncbi.nlm.nih.gov/pubmed/19595447
 De Hert et al. Physical illness in patients with severe mental disorders. I. Prevalence, impact of medications and disparities in health care. World Psychiatry 2011; 10: 52-77. http://www.ncbi.nlm.nih.gov/pubmed/21379357
 De Hert et al. Physical illness in patients with severe mental disorders. II. Barriers to care, monitoring and treatment guidelines, plus recommendations at the system and individual level. World Psychiatry 2011; 10: 138-51.http://www.ncbi.nlm.nih.gov/pubmed/21633691