Residual volume/total lung capacity ratio confers limited additive significance to lung clearance index for assessment of adults with bronchiectasis

Tiotropium in Patients with Bronchiectasis: A Prospective Cohort Study

PURPOSE

There are limited studies on the use of bronchodilators for the treatment of bronchiectasis. This study investigated the efficacy of tiotropium in patients with bronchiectasis and airflow limitation.

METHODS

This study was a prospective cohort study, including 169 patients with bronchiectasis and airflow limitation from 2015 to 2019. The clinical outcomes observed in our study were the effect of tiotropium on the frequency of moderate exacerbations, the time to the first severe exacerbation, and the annual decline in FEV₁.

RESULTS

After 12 months, the annual decline in the FEV₁ after bronchodilator use was 27.08 ml or 42.9 ml per year in the group with or without tiotropium, respectively. Treatment with tiotropium was associated with a decreased risk of moderate exacerbation of bronchiectasis (Adjusted RR 0.618 95% CI 0.493-0.774; P < 0.005). The time to the first severe acute exacerbation of bronchiectasis in the tiotropium group was longer than the non-tiotropium group (Adjusted HR 0.333 95% CI 0.219-0.506; P < 0.001).

CONCLUSION

In conclusion, prospective cohort study showed that tiotropium effectively ameliorated the annual decline in the FEV_1, with a lower-risk rate of moderate exacerbations and prolonging the time to the first-time severe exacerbation in patients with bronchiectasis and airflow limitation.

Multiple-Breath Washout Outcome Measures in Adults with Bronchiectasis

Rationale: Lung clearance index (LCI) has good intravisit repeatability with better sensitivity in detecting lung disease on computed tomography scan compared with forced expiratory volume in 1 second (FEV₁) in adults with bronchiectasis. Alternative multiple-breath washout parameters have not been systematically studied in bronchiectasis. Objectives: To determine the validity, repeatability, sensitivity, specificity, and feasibility of standard LCI (LCI^2.5), shortened LCI (LCI^5.0), ventilation heterogeneity arising within proximal conducting airways (S_condVT), and ventilation heterogeneity arising within the acinar airways (S_acinVT) in a cross-sectional observational cohort of adults with bronchiectasis. Methods: Cross-sectional multiple-breath nitrogen washout data (Exhalyzer D; Eco Medics AG) from 132 patients with bronchiectasis across five United Kingdom centers (BronchUK Clinimetrics study) and 88 healthy control subjects were analyzed. Results: Within-test repeatability (mean coefficient of variation) was <5% for both LCI^2.5 and LCI^5.0 in patients with bronchiectasis, and there was no difference in mean coefficient of variation for LCI^2.5 and LCI^5.0 in patients with bronchiectasis compared with healthy volunteers. Moderate-strength correlations were seen between FEV₁ and LCI^2.5 (r = -0.54), LCI^5.0 (r = -0.53), S_condVT (r = -0.35), and S_acinVT (r = -0.38) z-scores. The proportion of subjects with abnormal multiple-breath washout (z-score > 2) but in normal FEV₁ (z-score < -2) was 42% (LCI^2.5) and 36% (LCI^5.0). Overall results from the receiver operating characteristic curve analysis indicated that LCI^2.5 had the greatest combined sensitivity and specificity to discriminate between bronchiectasis and control subjects, followed by LCI^5.0, FEV₁, and S_condVT z-scores. There was a 57% time saving with LCI^5.0. Conclusions: LCI^2.5 and LCI^5.0 had good within-test repeatability and superior sensitivity compared with spirometry measures in differentiating between health and bronchiectasis disease. LCI^5.0 is quicker and more feasible than LCI^2.5. Clinical trial registered with www.clinicaltrials.gov (NCT02468271).

Characterization of the severity of dyspnea in patients with bronchiectasis: correlation with clinical, functional, and tomographic aspects

OBJECTIVE

To characterize a population of patients with bronchiectasis, correlating clinical, radiological, and functional aspects with the severity of dyspnea.

METHODS

This was a cross-sectional study involving adult patients with HRCT-confirmed bronchiectasis, categorized according to the severity of dyspnea (as being mildly or severely symptomatic, on the basis of the modified Medical Research Council scale). We correlated the severity of dyspnea with clinical parameters, functional parameters (spirometry values, lung volumes, and DLCO), and CT parameters.

RESULTS

We evaluated 114 patients, 47 (41%) of whom were men. The median age (interquartile range) was 42 years (30-55 years). The most common form was idiopathic bronchiectasis. Of the 114 patients, 20 (17.5%) were colonized with Pseudomonas aeruginosa and 59 (51.8%) were under continuous treatment with macrolides. When we applied the Exacerbation in the previous year, FEV1, Age, Colonization, Extension, and Dyspnea score, the severity of dyspnea was categorized as moderate in 54 patients (47.4%), whereas it was categorized as mild in 50 (43.9%) when we applied the Bronchiectasis Severity Index. The most common lung function pattern was one of obstruction, seen in 95 patients (83.3%), and air trapping was seen in 77 patients (68.7%). The prevalence of an obstructive pattern on spirometry was higher among the patients with dyspnea that was more severe, and most functional parameters showed reasonable accuracy in discriminating between levels of dyspnea severity.

CONCLUSIONS

Patients with bronchiectasis and dyspnea that was more severe had greater functional impairment. The measurement of lung volumes complemented the spirometry data. Because bronchiectasis is a complex, heterogeneous condition, a single variable does not seem to be sufficient to provide an overall characterization of the clinical condition.