Increased Burden of Pertussis Among Adolescents and Adults With Asthma or COPD in the United States, 2007–2019

Describe the incidence of pertussis and pertussis with complications from 2007 to 2019 in the Optum general population and to compare them with people with asthma or chronic obstructive pulmonary disease (COPD), overall and stratified by age. The frequency of asthma or COPD exacerbations during the 180 days before and after the diagnosis of pertussis was described in individuals with asthma or COPD.Eight hundred fifty adults, children, and adolescents with asthma and pertussis (322 aged 10-17 years). Outcomes of infection compared with the general population.Observational, retrospective database study conducted in an administrative health care claims system from a large national managed care company across all 50 states in the United States. Inclusion criteria included age 10 years or older during the study period from January 2017 through December 31, 2019, and 12 months of continuous health enrollment prior to cohort entry. Participants were divided into age groups, including ages 10 to 17 years, 18 to 44 years, 45 to 64 years, and 65 years and older. People with asthma or COPD were identified by 1 or more inpatient or 2 or more outpatient claims with the corresponding diagnosis. Patients with asthma were excluded if they had COPD, and vice versa. The asthma or COPD population were age and sex matched with 4 control patients from the general population without asthma or COPD. Pertussis cases were identified by International Classification of Diseases, Ninth Revision (ICD-9) or ICD-10 diagnosis codes. Pertussis with complications included pertussis with pneumonia, hospitalization, subdural hemorrhage, seizures, syncope, rib fracture, rectal prolapse, pneumothorax, and encephalitis within 90 days of initial pertussis diagnosis. Severe exacerbations of asthma or COPD were also included.Across the age ranges, the incidence of pertussis was highest in those aged 10 to 17 years. This age group also had the second highest incidence of complications (behind those aged ≥65 years). Individuals with asthma had a 3.57-fold higher risk of pertussis compared with the general population, noted for all age groups, highest in those aged 10 to 17 years, and a 4.12-fold higher risk of pertussis with complications. The highest risk was in those aged 18 to 44 years, with the 10- to 17-year-olds next. Asthma exacerbations occurred most frequently in the 30 days immediately before the pertussis diagnosis, returning to baseline 90 days after diagnosis. Rates of exacerbations during those time periods were 25.14% to 13.14%, respectively.Children and adolescents, aged 10 to 17 years, had the highest incidence of pertussis compared with adults, consistent with data from the Centers for Disease Control and Prevention. The incidence of pertussis and pertussis with complications was increased in patients with asthma compared with the general population.Pertussis cases are markedly increased this year, compared with previous years, and asthma care clinicians need to be aware that their patients are at higher risk for disease, complications, and exacerbations. Because asthma exacerbations most commonly occurred prior to pertussis diagnosis, pertussis may have been missed and diagnosed as an asthma exacerbation. Encourage all your patients with asthma to get immunized against pertussis.