Individuals with existing depression or anxiety appear to have an increased risk for death within 30 days of surgery, new research suggests.
A large, retrospective, cohort study of veterans conducted by investigators at the Iowa City Veterans Affairs Medical Center and the University of Iowa Carver College of Medicine, Iowa City, showed that 30-day mortality was higher for patients with psychiatric comorbidity (odds ratio, 1.21; 95% confidence interval, 1.07 – 1.37; P = .003).
Individual analyses revealed that the in-hospital and 30-day mortality risk was highest in those with depression (P = .01) or anxiety (P = .02) but was not significantly higher in patients with preexisting posttraumatic stress disorder (PTSD), bipolar disorders, or schizophrenia.
“Existing psychiatric comorbidity was associated with a modest increased risk of death among postsurgical patients. Estimates of the increased risk across the individual conditions were highest for anxiety and depression,” the authors, led by Thad E. Abrams, MD, write.
The study appears in the October issue of the Archives of Surgery.
Lack of Research
According to the study, previous research suggests psychiatric comorbidities are common among hospitalized patients, with prevalence estimates ranging between 5% and 40%. Furthermore, the researchers note, psychiatric comorbidity has been independently linked with an increased risk for morbidity and mortality.
However, they add, previous studies of psychiatric conditions have largely been limited to patients admitted to the hospital for medical conditions, not surgical procedures. The few studies that do exist on psychiatric comorbidity and surgical mortality are limited to patients with schizophrenia and depression.
The authors also note that “no known analyses have considered multiple psychiatric conditions separately in a single surgical cohort. Indeed the need for further work in this area was highlighted in a recent systematic review.”
To examine the potential effect of 5 existing psychiatric comorbidities, including depression, anxiety, PTSD, bipolar disorders, and schizophrenia, on postsurgical mortality, the investigators examined retrospective data from 35,539 surgical patients admitted to intensive care units from October 2003 through September 2006. The main outcome measure was in-hospital and 30-day mortality.
An existing psychiatric condition was identified in 8922 patients (25.1%). Of these, 5500 patients had depression (15.5%), 2913 patients had PTSD (8.2%), 2473 patients had anxiety (7%), 793 patients had bipolar disorder (2.2%), and 621 patients had psychosis (1.8%).
Greater Care Warranted
Before adjustment, 30-day death rates were similar among patients with and without psychiatric illnesses (3.8% vs 4%). However, after the researchers considered other factors in their analyses, 30-day death rates were higher for patients with psychiatric conditions.
In addition, the investigators found that 30-day death rates among those with psychiatric conditions were higher for those undergoing respiratory or digestive system procedures, but not procedures involving the circulatory, nervous, or musculoskeletal systems.
“Several potential mechanisms exist to explain these findings,” the authors write. “First, studies indicate that patients with depression frequently do not adhere to medical recommendations for underlying medical conditions. It is therefore plausible that such undertreated conditions may affect postoperative care and outcomes.
“Second, patients with existing psychiatric comorbidity may be more likely to undergo surgery by a lower-quality surgeon or hospital. Third, pre-existing psychiatric comorbidity may serve as an indicator for greater severity of surgical risk.”
These findings, say the authors, suggest greater care should be taken among patients with a psychiatric illness who are undergoing surgery.
“Until further research is completed, we recommend that surgeons caring for patients with a history of anxiety or depression seek early involvement of multidisciplinary teams to help identify problematic areas in perioperative care processes, particularly regarding issues of surgeon-patient communication and adherence to post-surgical recommendations,” they write.
The authors have disclosed no relevant financial relationships.
Arch Surg. 2010;145:947-953.