READ MOREDelirium is a state of confusion that comes on suddenly and is associated with longer ICU and hospital stays, increased costs of care and higher death rate. Known risk factors for developing delirium in the ICU include age, pre-existing cognitive impairment, and sedation (often used in conjunction with mechanical ventilation).
Prior to the new study by researchers from the Regenstrief Institute and the Indiana University Center for Aging Research, the relationship between race and delirium had not been systematically evaluated.
"Relationship between African-American Race and Delirium in the Intensive Care Unit" is published online ahead of print in the journal Critical Care Medicine.
"Since African-Americans tend to have higher disease severity in the ICU, we were surprised to find that race could be a protective factor for younger African-American adults," said Regenstrief Institute investigator and IU Center for Aging Research scientist Babar A. Khan, M.D., M.S., the first author of the study.
"We now know that race should be considered among the risk factors for developing delirium for Caucasians of all ages but only for African-Americans if they are 50 or older. Clearly, different groups have different risk profiles for delirium."
A total of 2,087 adults, admitted to a medical or surgical ICU, 48 percent of whom were African-Americans, participated in the study. The majority participated in an indigent care program or state Medicaid program and were thus considered to be of similar economic status.
All had ready access to healthcare services and delivery at Eskenazi Health, a healthcare system that puts special emphasis on vulnerable populations in the metropolitan Indianapolis area. Dr. Khan is the medical director of the Eskenazi Health Critical Care Recovery Center.
Based on patient data from the Regenstrief Medical Record System, the African-Americans and Caucasians had comparable death rates, illness severity and similar rates of mechanical ventilation and dementia diagnoses, however smoking and depression diagnosis were greater among Caucasians.
More drugs associated with delirium were prescribed for Caucasians than African-Americans.
The reasons why African-Americans have lower rates of delirium are unclear according to Dr. Khan and will need exploration in future studies. ■