What is the epidemiology of sepsis?

Epidemiology of Sepsis

Sepsis is a major global health burden with an estimated 48.9 million cases and 11 million deaths worldwide in 2017, accounting for nearly 20% of all global deaths. 1

Global Incidence and Mortality

• The global incidence of sepsis was estimated at 48.9 million cases in 2017, with 11 million sepsis-related deaths representing approximately 20% of all global deaths worldwide 1
• In the United States, the incidence of sepsis exceeds 1.7 million adults per year, with more than 15% of diagnosed patients dying and an in-hospital mortality rate exceeding 30% 2
• Sepsis accounts for 5.2% of total US hospital costs, amounting to more than $20 billion in 2011, with the incidence continuing to rise due to an aging population 2
• Despite declining age-standardized incidence (37% decrease) and mortality (52.8% decrease) from 1990 to 2017, sepsis remains a major cause of health loss worldwide 1

Regional Variations

• Sepsis incidence and mortality vary substantially across regions, with the highest burden in sub-Saharan Africa, Oceania, South Asia, East Asia, and Southeast Asia 1
• In middle- and low-income countries, sepsis represents a disproportionately high burden, with 90% of worldwide deaths from pneumonia, meningitis, and other infections occurring in less developed countries 2
• Approximately 70% of the 9 million global deaths in neonates and infants are attributable to sepsis, with the majority occurring in Asia and sub-Saharan Africa 2
• The incidence of neonatal sepsis in middle-income countries has been reported to be up to 40 times higher than in high-income countries 2

Risk Factors

• Risk factors for sepsis development overlap with risk factors for infection and include:
  • Immune compromise and chronic diseases such as malignancy 2
  • Specific demographics: infants and elderly persons, males, and Black race 2
  • High incidence of bacterial, parasitic, and HIV infections 2
  • Low hygienic standards and vaccination rates 2
  • Widespread malnutrition 2
  • Limited healthcare resources 2

Common Sources of Infection

• Chest infections (pneumonia) are the most commonly identified source of infection in sepsis, reported in 38.6% of patients in one study 2
• Pulmonary and intra-abdominal infections are the most commonly associated sites of infection identified in patients suffering acute lung injury related to sepsis 2
• In neonatal sepsis in low- and lower-middle-income countries, Gram-negative bacteria account for 60% of cases, with significant regional variations in the types of pathogens 2

Healthcare Impact and Resource Utilization

• Sepsis accounts for a significant proportion of intensive care unit (ICU) admissions, varying from 10% in Switzerland to 64% in Portugal, with countries having fewer ICU beds per capita showing a greater proportion of beds occupied by sepsis patients 2
• The availability of ICU beds impacts sepsis care, with countries having fewer ICU beds showing delayed ICU admissions and potentially higher mortality rates 2
• Hospital mortality from sepsis has historically ranged from 25% to 80%, though recent trends suggest declining rates 3

Complications and Outcomes

• The development of acute respiratory distress syndrome (ARDS) in patients with sepsis occurs in 25-42% of cases, with the risk increasing with persistent arterial hypotension 2
• Mortality in sepsis is most often due to unresolved sepsis or multisystem organ failure rather than progressive respiratory failure 2
• Factors affecting mortality include age, severity of illness, cause of lung injury, presence of multisystem organ failure, and preexisting comorbid conditions 2

Diagnostic and Treatment Challenges

• High rates of antimicrobial resistance are observed against WHO-recommended empirical antibiotics for neonatal sepsis in many low- and lower-middle-income countries 2
• CT imaging plays an important role in evaluating patients with suspected sepsis, with a high positive predictive value and the ability to lead to management changes in approximately 45% of cases 2
• Delayed ICU admission due to lack of beds is associated with substantially longer time in hospital before ICU admission and higher mortality, even after adjustment for case-mix 2

Understanding the epidemiology of sepsis is crucial for developing effective prevention strategies, improving early recognition, and implementing appropriate treatment protocols to reduce the substantial global burden of this condition.