Symptoms of chronic bronchitis in individuals without chronic obstructive pulmonary disease: prevalence, burden, and risk factors in southern Poland

Introduction Chronic bronchitis (CB) symptoms are commonly reported in individuals without chronic obstructive pulmonary disease (COPD), but CB is rarely diagnosed in this population.
Objectives We aimed to determine the prevalence and burden of CB, as well as its risk factors, in a population of patients without COPD.
Patients and methods Data from the “Health Action” program (a lung cancer prevention and health care improvement program conducted in Proszowice County, Poland) were used. All county inhabitants aged 40 years or older without COPD were invited to participate. As part of the program, a questionnaire was administered to assess CB symptoms and risk factors. Spirometry at baseline and after the bronchodilator test was also performed.
Results CB symptoms were present in 9.1% of the 3558 participants. The prevalence of CB in the study population was 7.12% (95% CI, 6.70–7.56). Patients with CB had more dyspnea and more often received medical treatment for lung disease or were hospitalized for respiratory disorders than patients without CB. CB was associated with worse lung function and a worse score in the modified Medical Research Council Dyspnea Scale even after adjustment for possible confounders. In a multivariate analysis, male sex, age over 70 years, current smoking, passive exposure to tobacco smoke, gas or wood heating, occupational exposure to chemical agents, lower forced expiratory volume in 1 second, and asthma correlated with an increased risk of CB.
Conclusions CB symptoms are common in individuals without COPD aged 40 years or older and are associated with more dyspnea irrespective of lung function and comorbidities.