OBJECTIVES: Pertussis is a contagious respiratory infection impacting individuals of all ages, especially adults and those with underlying conditions (UCs). This study aimed to assess pertussis-related healthcare resource utilization (HCRU) and costs in adults with and without UCs in Germany.

METHODS: A retrospective cohort study was conducted using German statutory health insurance claims data from 2015 to 2019. Patients ≥18 years, with and without UCs, reported with pertussis were matched 1:1 to patients without pertussis. Excess outpatient and prescription drug utilization and costs were estimated for the acute pertussis quarter and four quarters after. Hospitalizations were identified with a primary hospitalization diagnosis of pertussis. To capture uncertainty, cases with hospitalized pneumonia/encephalopathy in the acute quarter of pertussis were additionally evaluated.

RESULTS: A total of 4,382 pertussis patients and controls are included. Outpatient costs increase significantly in patients with pertussis in the index quarter (€119.32; 95%-confidence interval (CI): €107.50-€131.14) and are higher in patients with any-UC (€140.99; 95%-CI: €114.59-€167.38) then in those without-UC (€107.93; 95%-CI: €97.02-€118.83). Overall, costs remain elevated across the subsequent year. Prescription drug costs are significantly higher during the index quarter (€15.74; 95%-CI: €14.87-16.62) in the overall population, with higher costs in patients with UC (€18.42; 95%-CI: €17.19-€19.65) compared to those without-UC (€14.34; 95%-CI: €13.17-€15.51). Overall mean hospital costs are €2,761(SD: €1,055) with a mean length of stay (LOS) of 5.57 days (SD: 3.72). Mean hospital costs (UC: €2,955; SD: 1,262; without-UC: €2,466; SD: €528) and mean LOS (UC: 6.27 days, SD: 3.44; without-UC: 4.47 days, SD: 3.98) differ between patients with and without-UC.

CONCLUSIONS: Pertussis leads to increased healthcare service utilization not only during the infection but also in subsequent quarters. Costs remain high over a prolonged period with an increase in patients with UC. Direct hospital costs related to pertussis and LOS were also higher in patients with UC.