Adverse Events During Medical and Surgical Hospitalizations for Persons With Schizophrenia
Daumit GL, Pronovost PJ, Anthony CB, Guallar E, Steinwachs DM and Ford DE;
Commented by , 28 Apr 2006
Aim
It is well established that people with schizophrenia have a high risk of suffering from a number of comorbid medical problems, and that their life span is reduced on average by approximately 10 years. What is less clear are the circumstances associated with this phenomenon. Given the stigma towards mental illness and the lack of experience of staff in medical wards there is a hypothesis that more adverse events occur during the hospitalization of people with severe mental illness.
The aim of the current study therefore was to estimate the amount of adverse events during medical and surgical hospitalizations for persons with schizophrenia compared with non-schizophrenic patients. Furthermore, the relation between adverse events and intensive care unit admissions, in-hospital death, length of stay, and total costs for hospitalizations for people with schizophrenia was assessed.
Methods
In a cross-sectional design the authors included all discharges from all Maryland acute care medical and surgical hospitals in 2001 and 2002. 1,746 medical and surgical hospitalizations of adults with a secondary diagnosis of schizophrenia were compared with those of 732,158 hospitalizations of adults without schizophrenia.
The "Agency for Healthcare Research and Quality's Patient Safety Indicators (PSIs)" were used to detect adverse events in administrative data. The PSIs for hospitalizations for patients with a secondary diagnosis of schizophrenia were compared with those for patients without schizophrenia.
The association between schizophrenia and each PSI was determined adjusting for both patient and hospital characteristics. In addition, the association between each PSI and intensive care unit admission, in-hospital death, length of stay, and total costs were analysed. Only hospitalizations for patients with schizophrenia were included in the latter analyses.
Results
A number of adverse events were statistically significantly more frequent during hospitalizations of people with schizophrenia than among patients without schizophrenia: postoperative respiratory failure (odds ratio (OR) 2.08, 95% confidence interval (CI) 1.41 to 3.06, infections due to medical care (OR 2.49, CI 1.28 to 4.88), postoperative deep venous thrombosis (OR 1.96, CI 1.18 to 3.26), and postoperative sepsis (OR 2.29, CI 1.49 to 3.51).
Among the patients with schizophrenia the development of respiratory failure or sepsis was associated with at least twice the odds for intensive care unit treatment and death. The length of stay of patients with schizophrenia was at least ten days longer, and the median hospital costs were elevated by at least 20,000 USD for infections due to medical care, respiratory failure, deep venous thrombosis and sepsis.
Dr Leucht's comments
While it has been well-established that people with schizophrenia suffer from a number of comorbid medical conditions, this study is the first analysis showing that iatrogenic factors in terms of adverse events during hospitalizations may play a role. A limitation of the study is that adverse events could only be assessed post-hoc by using administrative data.
Clearly any data of this kind depend on the accuracy and on the completeness of reporting. It is also possible that pre-existing medical comorbid conditions of people with schizophrenia contributed to higher illness severity and worse outcomes.
Assuming that the high prevalence of adverse events during hospitalisations of people with schizophrenia is a true finding, explanations could be drug-drug effects (e.g. antipsychotic drugs are sedating and could interact with anaesthesia) or delayed recognition of symptoms due to problems in communicating with schizophrenic patients. Whatever the reason is, the authors conclude that efforts to reduce these adverse events should become a research priority.