A Johns Hopkins study of more than 1,700 patients with schizophrenia hospitalized for medical or surgical care unrelated to their mental disorder shows they are at least twice as likely as similar patients without schizophrenia to suffer dangerous and expensive adverse events. The adverse events are associated with poor outcomes, including death.

The researchers concluded that decreased quality of care given to patients with schizophrenia may put them at higher risk for serious infections and other complications.

A report on these findings appears in the March issue of the Archives of General Psychiatry.

“The results of our study suggest that having schizophrenia may be a previously unrecognized or under-appreciated contributor to higher likelihood of complications and death for patients admitted to a medical or surgical hospital service,” said Gail L. Daumit, M.D., M.H.S., an assistant professor of medicine at The Johns Hopkins University School of Medicine and first author of the report. The primary diagnoses in these cases were conditions that required immediate medical or surgical care.

The Hopkins team, composed of investigators from the School of Medicine and Bloomberg School of Public Health, evaluated patients discharged from Maryland acute care hospitals following medical or surgical treatment in 2001 and 2002. The patients included 1,746 patients who had schizophrenia and 732,210 who did not.

Using a set of standard patient safety indicators, or PSIs, developed by the Agency for Healthcare Research and Quality, the team found that patients with schizophrenia were two and one-half times more likely than non-schizophrenics to have hospital-associated infections; two times more likely to have postoperative respiratory failure or postoperative deep vein blood clots, and two times more likely to suffer post-operative sepsis (overwhelming infections throughout the body caused by toxin-producing bacteria) than patients without schizophrenia.

In addition, patients with schizophrenia who had respiratory failure or sepsis were twice as likely as those without respiratory failure or sepsis to be admitted to the intensive care unit and to die.

The team also found that the median length of hospital stay for patients with schizophrenia and adverse events was at least 10 days longer than the stay of schizophrenics without adverse events; and median hospital charges were at least $20,000 greater in hospitalizations with adverse events.

“Much of this increased risk could be due to variation of quality of care,” said Peter Pronovost, M.D., Ph.D., the medical director of the Center for Innovation in Quality Patient Care and a professor in the Department of Anesthesiology/Critical Care Medicine at Johns Hopkins University’s School of Medicine.

“We already were aware that individuals with schizophrenia have a high risk of premature mortality, but it wasn’t clear until now whether complications during hospitalization were a contributing factor,” Daumit said.

Previous studies by others suggest that health care professionals might minimize or misinterpret the medical symptoms of people with schizophrenia and delay diagnosis and treatment of conditions requiring attention, Daumit said. This is especially likely if these patients are hallucinating, behaving aggressively or communicating poorly.

Other factors contributing to poor outcomes may include improper use of restraints, excessive medication dosages and interactions of drugs used to control schizophrenia symptoms with other medications, Daumit noted. Such drug errors can cause over sedation, which in turn could cause respiratory problems, such as pneumonia, she said.

“Further research is needed to evaluate the extent to which having schizophrenia increases the risk for complications and death, and whether they are preventable and responsive to interventions to improve quality of care,” Pronovost said. He explained that more information about health care provider and system level factors such as communication between medical specialties and the availability of consultation-liaison psychiatric services would be important to target future quality improvement efforts.

PSIs are designed to help hospitals identify situations that might require further study, according to the Hopkins researchers. AHRQ is part of the U.S. Department of Health and Human Services.

Other authors of the study from Johns Hopkins University School of Medicine include Daniel E. Ford, M.D., M.P.H, vice dean and professor in the Department of Medicine, and Christopher B. Anthony, a research assistant in the Department of Medicine. Authors from the Bloomberg School of Public Health include Donald M. Steinwachs, Ph.D., a professor in the Department of Health Policy and Management, and Eliseo Guallar, Ph.D., an associate professor in the Department of Epidemiology.

This work was supported by the National Institute of Mental Health.