Study Identifies Risk Factors of Long-Term Mortality in Sepsis Survivors

Sepsis survivors have a greater risk of long-term mortality than patients hospitalized for other reasons, and a new study by investigators in the United Kingdom has found that older males with certain sites of infection had the greatest risk of long-term mortality.

Each year in the United States, approximately 1.7 million adults develop sepsis, leading to 270,000 deaths annually. For those who survive, the risk of mortality following hospital discharge continues to be higher than that of the general population, and about 1 in 6 sepsis survivors die within the first year following hospitalization for sepsis. In a new study published in the journal JAMA Network Open, investigators assessed how factors such as age, sex, site of infection, and other patient characteristics were independently associated with long-term mortality in a sepsis survivor population.

“When studying risk factors for long-term mortality in sepsis survivors, the factors associated with short-term mortality may overwhelm and disguise factors associated with long-term mortality—as observed in many sepsis epidemiology studies included in the recent systematic review,” the investigators wrote. “The reason for this is that an increase in sepsis severity may worsen cumulative long-term mortality by increasing hospital mortality.”

The 5-year study included a sepsis survivor cohort of 94,748 patients over the age of 16 years admitted to 192 adult general critical care units in England from April 1, 2009, to March 31, 2014. The mean patient age was 61.3 years, 54% were male, and 46.3% of patients had a respiratory infection. Among the sepsis survivors, 15% died by 1 year following hospital discharge, while 6% to 8% died each year over the next 5 years. Increasing age, male sex, 1 or more severe comorbidities, prehospitalization dependency, and nonsurgical status increased the risk of long-term mortality. In addition, the risk of long-term mortality differed by site of infection at index critical care admission for sepsis. Patients with respiratory and cardiovascular sepsis sites had a slightly greater risk for long-term morbidity, as did those with 2 or 3 organ dysfunctions compared with those with single organ dysfunction.

“When these factors independently associated with long-term mortality from our results are considered with those from the literature, it indicates that sepsis survivors both retain risk from index critical care admission for sepsis but also accumulate additional risk following hospital discharge from their worsening preexisting comorbidities and/or new comorbidities both of which are associated with increased risk of long-term mortality,” the research team reported. “Thus, our study makes a case for understanding how management following discharge could alter sepsis survivors’ risk of long-term adverse outcomes.”

To reduce long-term mortality, investigators say their findings will fuel efforts to target sepsis survivors and design interventions for those at risk. Future interventional trials, they suggest, may include clinical practice interventions such as extended follow-up care either by primary care physician or with targeted follow-up clinics or immunological interventions informed by acute sepsis illness biology.