Patients who experience a septic infection are at risk of developing mental and physical impairments later in life, a new study suggests.
Older adults who survived severe sepsis — a widespread bacterial infection usually accompanied by dangerously low blood pressure — were more likely to develop moderate to severe cognitive problems than adults hospitalized for other reasons, the researchers said.
Patients with sepsis also required assistance with more daily activities, including walking and getting dressed, after their infection than did adults who didn't have sepsis while hospitalized.
"For most older Americans, they suffer severe brain and body problems for years after sepsis," said study researcher Dr. Theodore Iwashyna, assistant professor of internal medicine at the University of Michigan Health System. "And these problems are large — they're of a magnitude that place a real burden on the family members who have to care for patients," and often lead to the patient being placed in a nursing home, he said.
Preventing sepsis, and the disabilities that arise from it, could reduce health care costs as well as the burden on patients' families, Iwashyna said.
The researchers estimate sepsis contributes to 20,000 new cases of cognitive impairment, such as dementia , in older adults per year.
Immune system in overdrive
Sepsis occurs when the body's normal immune system response, known as inflammation , gets out of control. It can start as a reaction to an infection, such as pneumonia, and go on to damage the body itself. When organs are damaged, the condition is known as severe sepsis. Sepsis affects hundreds of thousands of patients each year, and about 40 percent of people with the illness die from it.
Iwashyna and his colleagues looked at medical information from 516 people over age 50 who survived severe sepsis, and 4,517 older adults hospitalized for other conditions. Participants were assessed for cognitive problems as well as physical disabilities four years before their illness and about eight years afterward.
About 60 percent of sepsis patients experienced worsening cognitive or physical function , or both, after their infection, the researchers say.
Nearly 17 percent showed signs of moderate to severe cognitive impairment, compared with about 6 percent before the sepsis infection. Patients hospitalized for something other than sepsis did not show an increase in cognitive problems.
In addition, about 40 percent of sepsis patients later had trouble walking, and 20 percent needed assistance with activities such as going to the grocery store or preparing a meal, Iwashyna said.
"These are huge changes for previously very independent, functional adults who have survived sepsis," Iwashyna told MyHealthNewsDaily.
The low blood pressure and inflammation patients experience during sepsis may lead to brain damage that causes cognitive problems. Sepsis patients also frequently become delirious, a state known to be associated with Alzheimer's disease .
Inflammation and infection can attack the muscles, and lack of proper physical therapy during sepsis might also contribute to the patients' later disability, Iwashyna said.
Older patients should get their flu and pneumonia vaccines to reduce the risk of infections that can lead to sepsis. New treatments are also needed to prevent the cognitive and physical consequences of the condition, Iwashyna said.
The results will be published tomorrow (Oct. 27) in the Journal of the American Medical Association.