People with schizophrenia or bipolar disorder have a substantially raised risk of premature death, research warns, and the risk seems to be increasing. Attempts have been made in recent years to understand this “mortality gap,” but the current death rates from natural vs. unnatural causes remain unclear.
Dr. Uy Hoang of Oxford University, UK, and colleagues looked at hospital and death records from 1999 to 2006. By 2006, the mortality rate for patients with schizophrenia or bipolar disorder was about double the average for the population. What’s more, this mortality gap has widened over time, they report on the website of the British Medical Journal.
For schizophrenics, the risk was raised by 60 percent in 1999, but more than twofold by 2006. For people with bipolar disorder, it was 30 percent higher in 1999 and ninety percent higher by 2006.
About three-quarters of all deaths were classed as natural causes. Circulatory disease and respiratory disease were the main components of this increase.
The authors say, “There is a need for better understanding of the reasons for the persistent and increasing gap in mortality between discharged psychiatric patients and the general population, and for continued action to target risk factors for both natural and unnatural causes of death.” They conclude: “Optimizing the general health of people with schizophrenia warrants urgent attention.”
Commenting on the findings, Dr. Brian Miller of Georgia Health Sciences University points out that the well-documented link between schizophrenia and bipolar disorder and increased early death from natural causes “is an important public health problem.”
He calls for better integration of mental and physical health services after hospital discharge, “because integrated primary medical care is associated with improved outcomes.”
Over the past ten years, the raised rate of coronary heart disease, stroke, and cancer among people with severe mental illness has been the focus of much research. This raised rate is not clearly linked to medication, smoking, or social deprivation.
The reasons are “are little understood and likely to be complex,” say Dr. Hoang and colleagues, but “are likely to be influenced by adverse lifestyle and social factors associated with the presence of mental illness such as alcohol and illicit drug use, and exposure to poor housing.”
“There is an urgent need for more research to understand the contribution of the six leading global risk factors for mortality identified by WHO, namely, hypertension, smoking, raised glucose concentration, physical inactivity, overweight and obesity, and high cholesterol concentration, to excess mortality in people with severe mental illness, including schizophrenia and bipolar disorder,” they warn.
Late diagnosis and inadequate treatment of physical illnesses may also be contributing to the problem for people with schizophrenia, add the experts.
The finding that mortality for people with schizophrenia has widened recently is reflected in the findings of a systematic review by Dr. Sukanta Saha and colleagues based at the Queensland Center for Mental Health Research in Australia in 2007.
The team reviewed 37 studies based in 25 countries and found that most of the major causes of death were elevated in people with schizophrenia, and this has “worsened in recent decades.” It seems to affect men and women equally.
Risks increased during the three decades examined in the study. This finding is consistent with earlier studies, suggesting that “people with schizophrenia have not fully benefited from the improvements in health outcomes available to the general population,” say the researchers.
They point out that several of the newer, second-generation antipsychotic drugs can trigger metabolic syndrome, which is associated with a two- to threefold increase in death from cardiovascular disease and a twofold increase in deaths from all causes combined.
“Adverse health outcomes associated with weight gain and/or metabolic syndrome (e.g. heart attack or cancer) may take decades to fully emerge,” they warn. “In light of the rising risks already identified by this review, the prospect of further increases in mortality for schizophrenia is alarming.”
They conclude, “It is sobering to reflect on this paradox of schizophrenia treatment. As we become better at detecting and treating the core symptoms of schizophrenia, patients have worsening mortality rates.
“Given the potential for an even greater disease burden as a result of the introduction of second-generation antipsychotic medications, research aimed at optimizing the physical health of people with schizophrenia needs to be undertaken with a sense of urgency.”
Hoang, U., Stewart, R. and Goldacre, M. J. Mortality after hospital discharge for people with schizophrenia or bipolar disorder: retrospective study of linked English hospital episode statistics, 1999-2006. The British Medical Journal, 2011;343:d542.
Miller, B. J. Editorial: Hospital admission for schizophrenia and bipolar disorder. The British Medical Journal, 2011;343:d5652.
Saha, S., Chant, D. and McGrath, J. A systematic review of mortality in schizophrenia: is the differential mortality gap worsening over time? Archives of General Psychiatry October 2007, Vol. 64, pp. 1123-31.