Epidemiology and Risk Factors of Clostridioides difficile Infections in Germany: A Health Claims Data Analysis.

Introduction: Clostridioides difficile infection (CDI) is increasingly recognized as a public health threat at the community level in addition to being one of the most common causes of healthcare-associated infections. In Germany, the epidemiology of CDI is primarily informed by national hospital-based CDI surveillance. We used health claims data from Germany to obtain valuable insights on population-level disease burden and risk factors for CDI.

Methods: This was a retrospective cohort study using a representative sample from the InGef research database. Overall and age- and sex-stratified CDI incidence rates were estimated for German adults from 2013 to 2017 using different case definitions (i.e., main, broad, strict), and further stratified by setting (inpatient versus outpatient). Risk factors for CDI were assessed for the 2013-2016 period.

Results: The CDI incidence rate was high but declined by 15.3% from 2013 [141 (95% confidence interval, CI 137-145) cases/100,000 person-years] to 2017 [120 (95% CI 116-123)]. Annual CDI incidence rates were higher in female patients and the elderly. The most important risk factors for CDI were chronic inflammatory bowel disease [odds ratio (OR) 4.7, 95% CI 4.0-5.5], chemotherapy (OR 4.7, 95% CI 4.1-5.2), chronic kidney disease (OR 2.9, 95% CI 2.6-3.3), and ciprofloxacin receipt (OR 2.6, 95% CI 2.4-2.8).

Conclusions: Despite prevention strategies leading to declining incidence, CDI remains an important public health threat in Germany, with a high burden in the hospital setting and an outpatient epidemiology that is poorly understood. These findings, which are relevant both regionally and globally, can be used as a basis for further research on the full burden of CDI in Germany.