Delirium was associated with a significant decline in cognitive ability during the first year after cardiac surgery, according to study results. Researchers identified a trajectory characterized by an initial decline and prolonged impairment.
“Delirium after cardiac surgery is a common and serious complication that could adversely impact recovery,” study researcher Jane S. Saczynski, PhD, an assistant professor of medicine at the University of Massachusetts Medical School, told Healio.com. “Screening for delirium could help identify patients who need tailored transitional care and who may require extended rehabilitation services to ensure cognitive and physical recovery.”
Saczynski, along with Edward R. Marcantonio, MD, of Beth Israel Deaconess Medical Center, Sharon K. Inouye, MD, MPH, and Richard N. Jones, ScD, of Hebrew SeniorLife, and colleagues enrolled 225 patients aged 60 years or older who were planning to undergo coronary-artery bypass grafting or valve replacement. Participants were assessed preoperatively, daily during hospitalization starting on postoperative day 2, and at 1, 6 and 12 months after surgery. The researchers used the Mini-Mental State Examination (MMSE) to assess cognitive function, and delirium was diagnosed using the Confusion Assessment Method. Saczynski and colleagues examined participants’ performance on the MMSE in the first year after surgery, controlling for demographics, coexisting conditions and hospital and surgery type.
Results show that 46% of participants who developed delirium postoperatively had lower preoperative mean MMSE scores than those who did not develop delirium (25.8 vs. 26.9; P<0.001). In adjusted models, participants with delirium experienced a more significant decline in cognitive function 2 days after surgery, compared with those without delirium (7.7 vs. 2.1; P<0.001) and had significantly lower postoperative cognitive function at 1 month (24.1 vs. 27.4; P<0.001) and at 1 year (25.2 vs. 27.2; P<0.001). More participants with delirium had not returned to their preoperative baseline level at 6 months, compared with those without delirium (40% vs. 24%; P=0.01), but the difference between the two groups was not significant at 12 months (31% vs. 20%; P=0.055).
“Identifying patients at high risk for delirium and promoting the development of interventions to prevent delirium in patients undergoing cardiac surgery may reduce the rate of long-term cognitive impairment in this population,” the researchers wrote. “Patients in whom delirium develops after cardiac surgery may require further interventions and customized rehabilitation programs to optimize recovery.”
Disclosure: The researchers report no relevant financial disclosures.