Infectious Disease, University of Washington

Sepsis associated with 1 in 5 deaths worldwide, UW researchers say

U.S. Centers for Disease Control and Prevention [CDC] technician with a lab culture of a bacteria frequently associated with sepsisKlebsiella pneumoniae. Photo: CDC

Twice as many people as previously believed are dying of sepsis worldwide, according to an analysis published today in The Lancet. Among them are a disproportionately high number of children in poor areas.

Led by researchers at the medical schools of the  University of Pittsburgh and University of Washington, the study revealed 48.9 million global cases of sepsis in 2017 and 11 million deaths, representing 1 in 5 deaths worldwide.

Sepsis occurs when a person’s organs cease to function properly as the result of an out-of-control immune response to infection. Even if sepsis doesn’t kill its victims, it can create lifelong disabilities in survivors.

The large majority of sepsis cases – 85% in 2017 – occurred in countries with low or middle sociodemographic status. The highest burden was found in sub-Saharan Africa; the South Pacific islands near Australia; and South, East, and Southeast Asia.

Sepsis incidence was higher among females than males. By age, the incidence of sepsis peaks in early childhood, with more than 40% of all cases occurring in children under 5.

“We are alarmed to find sepsis deaths are much higher than previously estimated, especially as the condition is both preventable and treatable,” said Dr. Mohsen Naghavi, senior author on the study. He is a researcher at the Institute for Health Metrics and Evaluation (IHME)  and a professor of health metrics sciences at the  University of Washington School of Medicine in Seattle. “We need renewed focus on sepsis prevention among newborns and on tackling antimicrobial resistance, an important driver of the condition.”

For their analysis, Naghavi and colleagues leveraged the Global Burden of Disease study, a comprehensive epidemiological analysis coordinated by IHME.

The Global Burden of Disease 2017 study reports on 282 primary causes of death, not including sepsis, which is considered an intermediate cause of death.

A primary cause of death is the underlying condition (such as cancer) which leads to the intermediate cause (sepsis) that ultimately results in death.

Previous global estimates for sepsis were limited because they relied upon hospital databases from a select group of middle- and high-income countries.

The previous estimates overlooked the substantial burden of sepsis that occurs outside of the hospital, especially in low-income countries. Today’s study findings are unprecedented as they represent mortality both in and out of the hospital.

The study authors analyzed annual sepsis incidence and mortality trends from 1990 through 2017 and found rates are improving. In 1990, there were an estimated 60.2 million sepsis cases and 15.7 million deaths; by 2017, incidence had dropped by 19% to 48.9 million cases and deaths by 30% to 11.0 million.

The most common underlying cause of sepsis-related death in both 1990 and 2017 was lower respiratory infection.

“I’ve worked in rural Uganda, and sepsis is what we saw every single day. Watching a baby die of a disease that could have been prevented with basic public health measures really sticks with you,” said lead author Dr. Kristina E. Rudd, assistant professor in Pitt’s Department of Critical Care Medicine.

“I want to contribute to solving this tragedy, so I participate in research on sepsis. However, how can we know if we’re making progress if we don’t even know the size of the problem? If you look at any top 10 list of deaths globally, sepsis is not listed because it hasn’t been counted.

“So what is the solution? Well, to start with it’s basic public health infrastructure. Vaccines, making sure everyone has access to a toilet and clean drinking water, adequate nutrition for children and maternal health care would address a lot of these cases,” said Rudd, who is also a University of Pittsburgh Medical Center critical care physician. “But sepsis is still a problem here in the United States, where it is the No. 1 killer of hospital patients. Everyone can reduce their odds of developing it by getting the flu shot, and the pneumonia vaccine when appropriate. Beyond that, we need to do a better job preventing hospital-acquired infections and chronic diseases, like diabetes, that make people more susceptible to infections.

“Finally, for people in high-income countries who want to help reduce the rates of sepsis in low-income areas, we need to support research into treatments and advocate to our elected officials for the importance of supporting sepsis prevention and control efforts in low-income communities,” Rudd said.

Additional findings include:

  • In 2017, 33.1 million incident cases of sepsis, or two of every three cases, occurred in patients with an underlying infectious condition; the remaining 15.8 million incident cases occurred in individuals with underlying injuries or non-communicable diseases.
  • In countries with low sociodemographic status, the majority of sepsis-related deaths were due to infection, whereas in countries with high sociodemographic status most sepsis-related deaths were associated with non-communicable diseases.

The study is entitled “Global, regional, and national sepsis incidence and mortality, 1990-2017: analysis for the Global Burden of Disease Study.”

SEPSIS DEATH RATES (ALL AGES), 195 COUNTRIES AND TERRITORIES, 2017

Highest death rates

  1. Central African Republic: 771.1 deaths per 100,000 people
  2. Chad: 566.3
  3. South Sudan: 551.4
  4. Lesotho: 512.8
  5. Somalia: 491.2
  6. Niger: 475.8
  7. Guinea: 460.6
  8. Mali: 455.1
  9. Burkina Faso: 453.1
  10. Sierra Leone: 453.0

Lowest death rates

  1. Qatar: 10.8 deaths per 100,000 people
  2. Kuwait: 17.6
  3. Lebanon: 24.2
  4. Oman: 24.8
  5. Bahrain: 27.1
  6. Maldives: 27.4
  7. United Arab Emirates: 27.5
  8. Saudi Arabia: 29.7
  9. Iceland: 32.4
  10. Jordan: 33.1

SEPSIS INCIDENCE RATES (ALL AGES), 195 COUNTRIES AND TERRITORIES, 2017

Highest incidence rates

  1. Mali: 2,806.9 new cases of sepsis per 100,000 people
  2. Niger: 2,660.0
  3. Chad: 2,659.4
  4. Nigeria: 2,588.1
  5. Sierra Leone: 2,259.7
  6. South Sudan: 2,256.1
  7. Burkina Faso: 2,229.8
  8. Central African Republic: 2,196.1
  9. Guinea: 1,779.5
  10. Democratic Republic of the Congo: 1,683.6

Lowest incidence rates

  1. Qatar: 92.6 new cases per 100,000 people
  2. Kuwait: 115.8
  3. Bahrain: 127.1
  4. United Arab Emirates: 127.6
  5. Oman: 180.7
  6. Macedonia: 190.1
  7. Albania: 190.8
  8. Iceland: 191.6
  9. Montenegro: 195.8
  10. Tunisia: 198.4