Epidemiology And Outcome Of Hospitalized Infants With Pertussis

Background Pertussis during infancy is associated with significant morbidity and mortality. The objective of this study was to review the epidemiology and outcome of infants with pertussis. Methods We identified infants with diagnosis of pertussis and compared demographic and outcome data with others who did not have pertussis. Infants with pertussis were matched 1:1 with correlative propensity score using sex, hospital region, income quartiles, race, ventilation status, and All Patients Refined Diagnosis Related Groups severity score. Results A total of 2920 pertussis cases were identified (prevalence: 4.7/1000 discharges). Females (49% vs 43%), Hispanics (35% vs 25%), and lower income quartile group (39% vs 36%) represented more frequently among pertussis cases (P < 0.001). Mechanical ventilation (6% vs 4.7%, P = 0.001), pulmonary hypertension (PHTN) (36% vs 1%, P < 0.001), and extracorporeal membrane oxygenation (ECMO) use (0.65% vs 0.08%, P < 0.001) were common among pertussis patients. In the intubated patients with pertussis, 50% had PHTN, 10% required ECMO, and 1 patient received leukapheresis. The mortality rate was significantly higher among ventilated (10.9% vs 0.04%, P < 0.001), PHTN (1.4% vs 0.3%, P < 0.001), and ECMO (60% vs 0.3%, P < 0.01) patients with pertussis. The mean length of stay was longer (5.96 +/- 8.3 vs 4.53 +/- 10.6 days, P < 0.01) among pertussis patients. Comparing with matched controls, the mortality rate was higher (0.72% vs 0.34%, P = 0.048), PHTN was common (36.4% vs 0.82%, P < 0.01), and ECMO usage was more frequent (0.65% vs 0%, P < 0.01) among pertussis cases. Conclusions Pertussis is more prevalent among females, Hispanics, and lower income quartile groups. This large sample study shows lower mortality than recent studies in infants with pertussis.