Study examines why the elderly are less likely to survive burn injuries

TORONTO, Ontario (August 4, 2015) – A world-first study by Sunnybrook Health Science Centre researchers has taken a closer look at why elderly burn patients are far less likely to survive a burn injury than younger adults.

“Outcomes for children and adults with burns have greatly improved over the last 30 to 40 years, but the mortality rate has remained much higher for elderly burn patients. We tried to identify the reasons why, which has never been done before,” says Dr. Marc Jeschke, Director, Ross Tilley Burn Centre at Sunnybrook.

The researchers found the elderly to have a higher death rate, more complex pre-existing medical conditions, a higher risk of developing multi-organ failure, and a significantly longer hospital stay, of one day per percent burn, than younger adults.

“We found that the elderly did not have the same immune response as younger adults, which is necessary to fight disease and injury. Their bodies lack some of the essential stem cells that are essential for skin healing,” says Dr. Jeschke, who is also Professor, Department of Surgery, Department of Immunology, Division of Plastic & Reconstructive and General Surgery, University of Toronto.

The researchers also found that metabolic responses seemed to be reversed. “While younger patients moved into a state of less stress and less hyper metabolism over time, elderly patients showed the exact opposite trajectory," says Dr. Jeschke.

Dr. Jeschke and his research team found several abnormal markers in the elderly group of patients to explain these differences in outcome, including a delayed increase in metabolism, an increase in inflammation over time and delays in wound healing due to changes in a certain kind of cell, known as progenitor cells.

The study analyzed 1461 patients admitted to Sunnybrook’s burn centre between 2006 and April 2015. Patients were grouped into adults (ages 18-65) and the elderly (over age 65), using the World Health Organization’s current definition of elderly. Blood and tissue samples were collected from patients who required surgery, and demographic data were collected from all patients.

The researchers hope their findings will encourage others to continue studying how outcomes of elderly burn patients can be improved. “By learning the major differences that come with this age group, we will be able to better help elderly people who have been subjected to burn injuries,” says Dr. Saeid Amini-Nik, Junior Scientist, Sunnybrook Research Institute and Assistant Professor, Department of Surgery, University of Toronto.

The study, which received funding from Canadian Institutes of Health Research and National Institutes of Health, was published in the EBioMedicine Journal with an assigned DOI of 10.1016/j.ebiom.2015.07.040.