"Put simply, on average, patients with schizophrenia are two to three times more likely to die compared to the general population," said review co-author John McGrath, M.D., a professor at the Queensland Centre for Mental Health Research in Australia.
"People with schizophrenia suffer from hallucinations and what's called 'disorganized' thinking. Medications can control symptoms fairly quickly, but they have numerous side effects," said Thomas McGlashan, M.D., a professor of psychiatry at Yale University.
In the new review, McGrath and colleagues examined 37 studies from 1980 to 2006 that explored death rates among people with schizophrenia. The studies were from 25 countries, including a number from the United States.
The researchers found that the death rate among people with schizophrenia was about 2.5 times that of other people. Suicide was the biggest risk: Schizophrenia patients were almost 13 times more likely to commit suicide than other people.
"That number is a "tragic reflection on how suboptimal our current treatments are," McGrath said. McGrath thinks the divide may become even bigger in the future because newer medications for schizophrenia causes unhealthy side effects like weight gain and an increased risk of type 2 diabetes.
Many schizophrenic patients take their pills only sporadically because of their side effects. "Probably the most pernicious (side effect) is that they take the 'joie de vivre' out of life. Patients just don't often feel alive or with it or motivated," McGlashan said.
As a result, many stop taking their medications and end up having symptoms again. "They have to be re-hospitalized and put back on medication," he said. "It becomes a revolving door."
Even if people do take their schizophrenia medications, they have problems taking care of themselves when they become ill, McGlashan said. "They're less self aware, less motivated to do the kinds of things that are required for handling a lot of these disorders. Going to a doctor regularly, getting blood tests they don't do it, even when they're on medication."
Other possible factors may be at play, according to the review. Schizophrenic patients are more likely to engage in high-risk activities, and it may be possible that their genetic makeup makes them more prone to some illnesses like diabetes.
Overall, the report said, the findings 'suggest that this already disadvantaged group is not benefiting from the improved health of the community in an equitable fashion. A systematic approach to monitoring and treating the physical health needs of people with schizophrenia is clearly warranted'.
"But they're not really sure what causes that kind of reaction to begin with. It has something to do with the disorder, but it involves something different than the usual neurochemicals that the drugs target," McGlashan said.
"In the long term, we're working hard to try to figure out a cause of this disorder. It's going to be a while. We don't know how long," he added.
The study is published in the October 2007 issue of the Archives of General Psychiatry.