The Disease Burden and Healthcare Resource Utilization of Gram-Negative Multi-Drug Resistant Bacteria

OBJECTIVES: Gram-negative multi-drug resistant (MDR) bacteria are a major cause of hospital-acquired infections (HAI). Since elderly patients are at a high risk of mortality due to HAI, this study aimed to evaluate the disease burden and healthcare resource utilization of gram-negative MDR bacteria in the elderly population in Germany.

METHODS: This retrospective analysis was based on anonymized claims data of a German sickness fund (AOK PLUS), including patients (≥65 years) with at least one inpatient diagnosis of gram-negative MDR bacteria (ICD-10 code: U81!) included between 2010 and 2021 with an index date defined as the first diagnosis. Descriptive analysis included patient demographics, the average length of hospitalization, and the main diagnosis code recorded at index date. The frequency and average length of all-cause hospitalization were determined for one-year follow-up and patient mortality at 3/6/9/12 months after index was calculated using Kaplan-Meier methodology. The annual prevalence of MDR among all hospitalizations for patients aged ≥65 was estimated for each year of 2017 to 2021.

RESULTS: A total of 18,058 patients with an inpatient diagnosis of gram-negative MDR were identified (female: 52%, mean age: 80 years, mean CCI: 4.0, average index hospitalization length: 21 days). Heart failure (ICD-10: I50, n= 984), complicated urinary tract infection (ICD-10: N39, n= 929) and sepsis (ICD-10: A41, n= 911) were the most common reasons for hospitalization. During the 1-year follow-up, patients experienced an average of 2 hospitalizations (all-cause) and the mean length of hospital stay was 16 days. Patient mortality at 3/6/9/12 months after index date was 26%/35%/40%/44%, respectively. The annual prevalence of gram-negative MDR bacteria in the elderly population has decreased by almost 50% from 2017 (1.73%) to 2021 (0.90%).

CONCLUSIONS: The study revealed a decline in the annual prevalence of gram-negative MDR infections while observing high mortality rates throughout the one-year follow-up period.