Delirium among nursing home residents often goes undiagnosed and needs to be treated more seriously than it currently is by long-term care professionals, a new research review has found.

The review showed that delirium affects nearly 1 in 5 (18%) long-term care residents, and carries a 40% one-year mortality rate. Due to the similarities between delirium symptoms and dementia, the former often goes undiagnosed or misdiagnosed in older patients, the review’s authors said in the Journal of the American Osteopathic Association.

Some of the studies included in the review showed links between delirium and a long-term care facility’s environment. Residents were more likely to have delirium-linked disruptive behavior when there was no clock or telephone in their room; restraints also upped the risk for delirium.

Lead author Martin Forsberg, M.D., with the Rowan University School of Osteopathic Medicine, advised providers to reduce residents’ non-essential surgeries, hospitalizations and medications in order to help prevent delirium.

“I think, historically, we have thought of delirium as a relatively benign condition,” Forsberg said. “The data tells us we need to treat it more scientifically and more seriously than we do.”

The review also found antipsychotic medications to be a successful treatment for delirium, a finding that came with the caveat that such medications also have been linked to increased risk of death for patients with dementia.