Burden and impact of pertussis in patients with chronic obstructive pulmonary disease exacerbation.

Pertussis is highly prevalent in chronic obstructive pulmonary disease (COPD) patients, but it is underrecognized and underreported in India. This study aims to assess the burden and impact of pertussis in patients with COPD acute exacerbations and also evaluates the correlation between pertussis and COPD exacerbation. This is a prospective, observational, cross-sectional study enrolling 250 COPD patients admitted with moderate to severe exacerbation. Relevant investigations and oropharyngeal swabs for pertussis were collected from the study subjects. Among 250 patients with COPD acute exacerbation, a throat swab was positive for Bordetella pertussis in 40 (16.1%) of subjects. Among positive subjects, 45% had moderate and 55% had severe exacerbation. Pertussis-positive subjects had statistically significantly higher COPD assessment test scores (p=0.02), more exacerbations in the past year (p=0.03), associated coronary artery disease (p=0.007), pulmonary hypertension (p=0.001), significantly lower forced expiratory volume in 1 second values (p=0.04), exercise-induced desaturation (p=0.02), and belonged to group E GOLD category (p=0.01), compared to negative subjects with no significant difference in mortality. 55% of pertussis-positive patients required intensive care unit (ICU) admission compared to negative subjects (p=0.04). Further, within swab-positive patients, physiological indicators like peripheral oxygen saturation and diffusing capacity of the lung for carbon monoxide significantly predicted ICU need. This study demonstrates that COPD patients are potentially at increased risk of pertussis infection, and there is an association between pertussis infection and COPD severity. Vaccination coverage against pertussis among COPD patients is negligible. Large multicenter studies are required to establish the true burden of pertussis in COPD patients, including the healthcare costs.