SAN DIEGO ─ Although it's present in only a tenth of all patients who are admitted to the hospital, sepsis contributes to up to half of all hospital deaths in the U.S., according to a study presented at the American Thoracic Society's annual conference here.
Although many studies have examined the incidence and mortality of patients diagnosed with sepsis in the U.S. over time, the study authors say that so far, the impact of sepsis on overall hospital mortality has been poorly understood. THe data were also published simultaneously as a research letter in JAMA.
"Our study was designed to quantify the national impact of sepsis on hospitalized patients and to highlight the importance of sepsis care on mortality at a population level," said study lead author Vincent Liu, M.D., M.S, of the Kaiser Permanente Northern California Division of Research.
Theodore Iwashyna, M.D., senior author of the study and a University of Michigan Health System and VA Ann Arbor critical care physician, says, "Although patients may have been weakened by heart disease or cancer or other chronic diseases, it is often sepsis that leads to their death. Preventing death from sepsis is a core strategy for improving care for many, many conditions -- conditions that people might think are not related to acute infections."
For their study, the researchers conducted a retrospective analysis of 6.5 million hospital discharge records derived from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (NIS) in 2010. The NIS is the largest publicly-available, all-payer inpatient database in the U.S., containing data from 100 percent of hospital discharges from a stratified sample of community hospitals.
Using diagnosis and procedure codes, the researchers identified hospital admissions and deaths of patients with sepsis and estimated the percentage of total hospital charges associated with sepsis hospitalizations.
At the end of their analysis, they found that sepsis patients had a hospital mortality rate of 10.4 percent compared to a rate of 1.1 percent in patients who did not have sepsis. They also found that of all hospital deaths nationally, as many as 52.0 percent were among patients diagnosed with sepsis. Sepsis hospitalizations also contributed to 21.2% of all hospital charges.
Sepsis is a serious medical issue in the U.S., affecting as many as 750,000 hospitalized patients in the U.S. annually, according to data from the Centers for Disease Control and Prevention (CDC). Between 2000 and 2010, deaths due to septicemia increased 17% despite an overall decline in overall hospitalization rates, and hospital deaths due to septicemia increased from 45,000 to 135,000 during the same period.
According to the Agency for Healthcare Research and Quality (AHRQ), sepsis is the most expensive cause of hospitalization in the United States, accounting for more than $24 billion annually.
"We were surprised to find that as many as 1 in 2 patients dying in US hospitals had sepsis. Teasing apart these findings in a similar regional study of sepsis mortality at Kaiser Permanente Northern California, we found that most patients already had sepsis at the time of hospital admission. There was also a large number of patients with less severe sepsis, a group for whom treatment guidelines are less well-defined," Dr. Liu said. "The results of our study suggest that improved care for sepsis patients of all severity levels and in all hospital settings could result in many future lives saved."
Iwashyna, an associate professor in the Pulmonary and Critical Care division of the Department of Internal Medicine at the U-M Medical School, is a member of the U-M Institute for Healthcare Policy and Innovation, the U-M Institute for Social Research, and the VA Center for Clinical Management Research at the Ann Arbor VA.
Reference: ATS 2014 Abstract 50626 and JAMA doi:10.1001/jama.2014.5804
Funding: The research was supported by the Permanente Medical Group, the Kaiser Foundation Hospitals and Health Plan, the Gordon and Betty Moore Foundation, and U.S. Department of Veterans Affairs Health Services Research & Development grant IIR 11-109.