Subject and study design
A cohort study was carried out in a university hospital in the State of Rio de Janeiro, from January 2017 to May 2018. Patients over the age of eighteen were recruited from an outpatient clinic specializing in pulmonology. All patients underwent high resolution computed tomography (HRCT), which is considered the gold standard for the diagnosis of bronchiectasis. The Research Ethics Committee of the University Hospital Pedro Ernesto, Brazil approved the research (no. 1,823,665). The patients were individually interviewed, a structured questionnaire with demographic and clinical data was administered. Then, the Quality of Life Questionnaire (EQ–5D–3L), the Modified Medical Research Council (mMRC) scale and the pulmonary function test were scheduled. During the 12-month follow-up, the interviews were conducted by telephone or face-to-face contact before or after medical appointments, with an interval of three months. At the end of 1 year, the patients underwent a new spirometric test and responded to the EQ–5D–3L and the mMRC questionnaires.
There are several factors that favor the development of bronchiectasis1,9,10. In this study, we considered the following groups: Idiopathic, Post-infectious by pulmonary tuberculosis (TB), Post-infectious non-TB, Primary immunodeficiency (common variable immunodeficiency), Kartagener’s syndrome and “Undetermined”. The cases in which the etiology was under investigation or was incomplete were classified as “undetermined” etiology.
Exacerbation was defined as the care of the patient in an outpatient unit when not previously scheduled or in an emergency unit, with or without the need for antibiotic therapy intervention, with the at least three of the following four clinical data: increased dyspnea intensity; increased daily volume of sputum, altered secretion color or fever4,14 (>37.5°C). Sputum was defined as mucoid (clear), mucopurulent (pale yellow/pale green) and purulent (dark yellow/dark green) by Murray et al15.
Patients who had a daily cough with a mucoid, mucopurulent or purulent sputum for at least three consecutive months in the 12-month period were considered as having “wet” bronchiectasis.
Functional indices such as the pre- and post-bronchodilator forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC) and FEV₁/FVC ratio were evaluated at the initial consultation and after 12 months. Ventilatory disorders were defined according to the criteria published by the American Thoracic Society (ATS)/European Respiratory Society (ERS): normal, obstructive, restrictive and mixed16.
Baseline and follow-up questionnaire
The baseline questionnaire contained the following data for collection: age, body mass index (BMI), number of exacerbations, emergency visits, hospitalizations, presence of fever (>37.5°C), increased dyspnea and sputum, change in sputum color and appearance, hemoptysis, degree of dyspnea (mMRC), therapeutic intervention with antibiotics, smoking (active, passive, ex-smokers and nonsmokers), spirometry, etiology, “wet bronchiectasis,” number of affected lobes (the lingula was considered a separate lobe), daily approximate volume of sputum, comorbidities, vaccines (influenza and pneumococcal), respiratory physical therapy, colonization with Pseudomonas aeruginosa (PA), Aspergillus and infections caused by non-tuberculous mycobacteria (NTM). Items monitored at follow-up: number of exacerbations, emergency visits, hospitalizations, presence of fever (>37.5°C), increased dyspnea and sputum, change in sputum color and appearance, hemoptysis, and antibiotic therapy.
Quality of life questionnaire
The quality of life questionnaire is an instrument composed of the EQ–5D–3L questionnaire and the Visual Analogue Scale (VAS)11. The EQ–5D–3L jointly addresses physical functions (mobility, self-care and pain/discomfort domains), social functions (habitual activities domain), and mental functions (anxiety/depression domain). Each domain/dimension is related to three levels of severity (no problems, some problems and extreme problems)11. The VAS consists of a ruler numbered from zero (worst health state imaginable) to 100 (best health state imaginable)11 and the patient records the value that best represents his/her health state at the time. The survey was registered in the EuroQol Research Foundation website and an authorization to apply the self-complete version of the EQ–5D–3L questionnaire and the face-to-face version of the EQ–5D–3L for patients with reading or writing difficulties was obtained. Ninety-seven (97%) patients did not need assistance in responding to the questionnaire, which was considered simple to understand and fast to fill out. A validated version of the questionnaire in Portuguese was used in the study, which assesses the specific health status of the Brazilian population (243 health states)11.
For the sample calculation, a standard deviation of 0.5 was considered, requiring 50 patients to detect a 7% difference in the quality of life with 95% confidence and 80% power. Numerical data were presented using mean and standard deviation or median and interquartile range, and categorical data using percentage and absolute values. Student’s T, Mann-Whitney, Kruskal Wallis, ANOVA, Chi-squared and Exact Fisher tests were used. For the elaboration of the graphs, the plotly package was used.