The aging of the U.S. population will lead not to increased emergency department visits, but to an increase in "boarding" and an increase in subsequent hospital admissions, according to the results of a data analysis.
The researchers used the National Hospital Ambulatory Medical Care Survey and data from the U. S. Census Bureau.
From 1997 to 2009, the population grew by 15%, while annual emergency department visits increased by 43%, prompting the Institute of Medicine to describe U.S. emergency care as "at the breaking point."
Moreover, the U.S. population is aging, and visits by older patients are viewed as a driving force in demand for emergency department services, according to Dr. Daniel J. Pallin, director of research in the department of emergency medicine at Brigham and Women’s Hospital, Boston, and his colleagues.
Using hospitalization rates observed during 1993-2009 and age subgroup–specific values from the period 2003-2009, Dr. Pallin and his colleagues modeled the effect of population aging on the demand for emergency department services. The results of their research – projecting through the years 2009-2050 – appear in the July issue of Health Affairs.
Overall, their projections showed that as the population increased at a growth factor of 1.4 (from 307 million in 2009 to 439 million in 2050), ED visits also increased at the same rate of 1.4 (from 136 million to 197 million), "refuting our initial hypothesis" that an aging population would lead to more ED visits, the researchers explained.
Their subgroup analysis provide an explanation. It showed that there were three peaks in the relationship of age to ED visit rates. The yearly rate of visits was 7 for every 10 children aged 0-4 years; 5.4 for every 10 adults aged 20-24; and 10 visits for every 10 adults aged 95-99. "Most notable is the fact that adults ages 60-80, who are the most numerous older Americans, are not heavy uses of the ED. For example, there are only 3.5 visits per year for every 10 adults ages 65-69," the researchers said.
"We observe that it is actually infants and young adults, not the elderly, who account for the largest number of ED visits. Although it is true that people older than 80 are most likely to visit the ED, they make up only 3.7% of the population and thus contribute little to the total national number of visits," the researchers wrote.
In contrast, the visit lengths in the ED (calculated as visit length minus waiting time) increased almost linearly with age. The mean visit length for small children was about 1.6 hours vs. more than 3.5 hours for the oldest patients.
Similarly, the likelihood of a hospital admission from an ED increased with age: 10% in small children and rising to almost 50% for the oldest patients. Patients use ED resources while waiting to move to hospital rooms, and this scenario, known as ‘boarding,’ is a major cause of ED crowding and a threat to patient safety, the researchers stated.
"We project that the aggregate length of ED visits will increase 10% by 2050. To keep pace, EDs must expand 10% faster than population growth, or the process of hospital admission will have to become more efficient," they noted (Health Aff. 2013;32:1-7).
"Hospitalizations from the ED will increase 23% faster than the anticipated rate of population growth," and to keep pace, hospitals must grow faster than the population and must optimize movement of admitted emergency department patients, they concluded.
The authors reported no relevant disclosures. The research was funded by a seed grant from the Brigham and Women’s Hospital’s department of emergency medicine.