When patients are moved into isolation while admitted in hospital, they are twice likely to develop delirium, a risky state of mental status impacting hospital patients. However patients who began their stay in isolation were not at worse risk.

The study, published in the January issue of Infection Control and Hospital Epidemiology, the journal of the Society for Healthcare Epidemiology of America, is the largest of its kind to examine the link between delirium and measures taken to prevent the spread of hard-to-treat infections such as MRSA. The measures, known as contact precautions, require patients to be isolated in their own room, and for healthcare personnel to wear masks, gowns, and other protective equipment. Some clinicians have been concerned that contact precautions may be disorienting to patients, making delirium more likely. Though delirium is generally a temporary condition, it can often adversely affect patient care. Symptoms include confusion, an inability to pay attention, and fluctuations in alertness.

A team of researchers led by Dr. Hannah Day of the University of Maryland School of Medicine examined two years of data from the university's 662-bed medical center. They found that patients who were placed on contact precautions at some point after admission to the hospital were 1.75 times more likely to develop delirium. However, patients on contact precautions starting at admission were no more likely to develop delirium. That finding, the researchers say, suggests that it may not be the precautions themselves causing delirium.