Urban–Rural Disparities in Case Fatality of Community-Acquired Sepsis in Germany: A Retrospective Cohort Study

Background: We aimed to examine urban–rural disparities in sepsis case fatality rates among patients with community-acquired sepsis in Germany. Methods: Retrospective cohort study using de-identified data of the nationwide statutory health insurance AOK, covering approx. 30% of the German population. We compared in-hospital- and 12-month case fatality between rural and urban sepsis patients. We calculated odds ratios (OR) with 95% confidence intervals and the estimated adjusted odds ratio (OR adj ) using logistic regression models to account for potential differences in the distribution of age, comorbidities, and sepsis characteristics between rural and urban citizens. Results: We identified 118,893 hospitalized patients with community-acquired sepsis in 2013–2014 with direct hospital admittance. Sepsis patients from rural areas had lower in-hospital case fatality rates compared to their urban counterparts (23.7% vs. 25.5%, p < 0.001, Odds Ratio (OR) = 0.91 (95% CI 0.88, 0.94), OR adj = 0.89 (95% CI 0.86, 0.92)). Similar differences were observable for 12-month case fatalities (45.8% rural vs. 47.0% urban 12-month case fatality, p < 0.001, OR = 0.95 (95% CI 0.93, 0.98), OR adj = 0.92 (95% CI 0.89, 0.94)). Survival benefits were also observable in rural patients with severe community-acquired sepsis or patients admitted as emergencies. Rural patients of <40 years had half the odds of dying in hospital compared to urban patients in this age bracket (OR adj = 0.49 (95% CI 0.23, 0.75), p = 0.002). Conclusion: Rural residence is associated with short- and long-term survival benefits in patients with community-acquired sepsis. Further research on patient, community, and health-care system factors is needed to understand the causative mechanisms of these disparities.