Late Breaking Abstract - The burden of pertussis in adults with asthma: a retrospective database study in England

Introduction: Pertussis is under-recognized in older adults, especially those with chronic conditions like asthma. It is important to estimate the incidence and economic burden of pertussis in these populations. Objectives: To estimate the burden of reported pertussis cases among ≥50-year-olds (≥50yo) and in an asthma sub-population (≥50yo+Asthma) in England, 2009-18. Methods: A retrospective observational study was conducted using the Clinical Practice Research Datalink, GOLD and Aurum databases, linked to Hospital Episode Statistics. Occurrence of pertussis and asthma were identified by diagnostic codes. Incidence rates (IRs) of pertussis among ≥50yo and ≥50yo+Asthma cohorts were estimated. Healthcare resource utilization will be presented in the poster. Results: Among ≥50yo, 28.5 million (m) person-years follow-up (PYFU) were included, with 3.6m PYFU ≥50yo+Asthma. Across the study period, IRs of pertussis were statistically higher in ≥50yo+Asthma than the ≥50yo cohort (9.61 (95% CI: 8.63-10.68) and 5.76 (5.48-6.04) /100,000 PYFU, respectively), with point estimates consistently higher over time. Observed IRs decreased with age in both groups. Conclusions: The incidence of diagnosed pertussis was higher among ≥50yo+Asthma patients than the ≥50yo cohort. Considering other literature suggesting under-diagnosis of pertussis, further research is warranted on the potential health and economic impact of pertussis in asthmatics.