The economic burden of nosocomial infections for hospitals: evidence from Germany

Nosocomial infections (NI) significantly worsen patient outcomes, resulting in higher mortality rates and reduced health-related quality of life. Furthermore, they pose substantial economic strain on healthcare systems and hospitals. For instance, patients with nosocomial infections (NIs) experience prolonged hospital stays compared to those without NIs. These extended stays result in occupied bed-days, leading to opportunity costs for hospitals. This study aimed to estimate the opportunity costs for a German hospital based on hospital stays, daily revenue, and occupancy rates (OCR).

We analysed cost data obtained from routine records maintained by the accounting department of a German hospital's surgical and orthopedic units from 2018 to 2019 for the "HygArzt" research project. To ensure balance, we employed genetic matching. We estimated the differences in length of stay (LOS) and daily revenue between patients with and without nosocomial infections (NI) using linear regression. Finally, we calculated the opportunity cost borne by the hospital by treating NI patients instead of non-NI patients. All costs are reported in 2018 Euros.

The final sample included 81 patients with NI matched with 207 patients without NI. The majority of the NI patients (77.0%) had surgical site infection (SSI). Compared to non-NI patients, we observed that NI patients had a longer LOS (10 days, p < 0.001) and lower daily revenue (€400, p < 0.001). We also found that comorbidities and the frequency of operations had significant impact on the LOS. Using a baseline 30 to 50% preventable NIs, successful prevention of a single NI could potentially reduce the length of hospital stay by 3 to 5 days and increase hospital revenue by approximately €120 to €200 per day per prevented NI. Consequently, the hospital saves 3 to 5 more bed-days to backfill and generate more revenue, and/or make more efficient resource allocation by changing bed-capacity and staffing. The resulting opportunity costs can potentially exceed €1,000 per preventable case.

NIs pose a substantial economic burden for hospitals. From a health economics' perspective, there are strong economic incentives for hospitals to implement infection control interventions, such as the involvement of a prevention link physician/nurse.