Behavioral profile of possible Alzheimer's disease patients in Virginia search and rescue incidents

Abstract

We performed a retrospective study of the behavior of lost dementia of Alzheimer's type (DAT) patients who became the subjects of organized search and rescue efforts. We compared the DAT patients' behavior to the behavior of elderly lost victims who possessed normal cognitive abilities. Data for both populations were from the Virginia Department of Emergency Services lost-subject database. We found that normal elderly individuals on average traveled a greater straight-line distance (2.56 km) from the point last seen (PLS) than did DAT patients (0.88 km). The median straight-line distance from the PLS was the same for both populations (0.8 km). The mortality rate for DAT patients was 19%. Mortality was caused by hypothermia, dehydration, and drowning. No fatalities were found among DAT patients when they were located within 24 h. A mortality rate of 46% was found for patients requiring more than 24 h to locate. This 24-h survivability window suggests that lost DAT patients require an immediate and aggressive search response.