Hui-min Li

Aetiology of bronchiectasis in Guangzhou, southern China.

Aetiologies of bronchiectasis in mainland China and their comparisons with those in western countries are unknown. We aimed to investigate bronchiectasis aetiologies in Guangzhou, southern China, and to determine ethnic or geographic differences with reports from western countries.

Characterization of Lung Function Impairment in Adults with Bronchiectasis

Background Characteristics of lung function impairment in bronchiectasis is not fully understood. Objectives To determine the factors associated with lung function impairment and to compare changes in spirometry during bronchiectasis exacerbation and convalescence (1 week following 14-day antibiotic therapy). Methods We recruited 142 patients with steady-state bronchiectasis, of whom 44 with acute exacerbations in the follow-up were included in subgroup analyses. Baseline measurements consisted of chest high-resolution computed tomography (HRCT), sputum volume, purulence and bacteriology, spirometry and diffusing capacity. Spirometry, but not diffusing capacity, was examined during acute exacerbations and convalescence. Results In the final multivariate models, having bronchiectasis symptoms for 10 years or greater (OR = 4.75, 95%CI: 1.46–15.43, P = 0.01), sputum culture positive for Pseudomonas aeruginosa (OR = 4.93, 95%CI: 1.52–15.94, P<0.01) and HRCT total score being 12 or greater (OR = 7.77, 95%CI: 3.21–18.79, P<0.01) were the major variables associated with FEV1 being 50%pred or less; and the only variable associated with reduced DLCO was 4 or more bronchiectatic lobes (OR = 5.91, 95%CI: 2.20–17.23, P<0.01). Overall differences in FVC and FEV1 during exacerbations and convalescence were significant (P<0.05), whereas changes in other spirometric parameters were less notable. This applied even when stratified by the magnitude of FEV1 and DLCO reduction at baseline. Conclusion Significant lung function impairment should raise alert of chest HRCT abnormality and sputum culture positive for Pseudomonas aeruginosa, in patients with predominantly mild to moderate steady-state bronchiectasis. Acute exacerbations elicited reductions in FVC and FEV1. Changes of other spirometric parameters were less significant during exacerbations. Trial Registration ClinicalTrials.gov NCT01761214

Impulse oscillometry in adults with bronchiectasis.

RATIONALE The usefulness of impulse oscillometry (IOS) in bronchiectasis has not been systematically investigated. OBJECTIVES To determine the usefulness of IOS parameters and their correlation with radiology, disease severity, sputum bacteriology, and spirometry, and to compare the changes in IOS parameters during exacerbations and convalescence of bronchiectasis. METHODS We recruited 100 patients with bronchiectasis and 28 healthy subjects. Receiver operating characteristic curve was plotted to analyze the diagnostic performance of IOS parameters. Chest high-resolution computed tomography (HRCT), Bronchiectasis Severity Index (BSI) assessment, sputum culture, and spirometry were performed. Correlation between IOS parameters and clinical indices was determined using the Spearman model. Changes in IOS parameters, compared with spirometry, during exacerbation were assessed in 16 patients with bronchiectasis. MEASUREMENTS AND MAIN RESULTS IOS parameters (in particular, resonant frequency) could discriminate patients with bronchiectasis from healthy subjects. Higher levels of IOS parameters were associated with Pseudomonas aeruginosa infection, dyshomogeneity, higher BSI and HRCT score, more bronchiectatic lobes, and cystic bronchiectasis (all P < 0.05). All IOS parameters but lung resistance at 5 Hz were positively correlated with the duration of bronchiectasis symptoms, number of bronchiectatic lobes, HRCT total scores, and BSI (all P < 0.05), but not sputum bacterial density (P > 0.05). IOS parameters, but not spirometric parameters, were not statistically different between peripheral and peripheral plus central segment bronchiectasis (all P > 0.05). Increased frequency dependence (higher resonance frequency or reactance area) was more likely to be associated with lower HRCT scores (≤5) than FEV1. Compared with FEV1, any single IOS parameter being abnormal was more common in mild bronchiectasis, particularly in patients with HRCT score of 5 or lower. IOS parameters were not statistically different from baseline to exacerbations and convalescence (all P > 0.05). CONCLUSIONS IOS parameters correlate with clinical indices and could reflect peripheral airway abnormality. An increased number of aberrant IOS parameters signals poorer clinical conditions. Increased frequency dependence might be a sensitive marker of mild bronchiectasis. Any single IOS parameter being abnormal sensitively reflects mild bronchiectasis. IOS parameters do not change significantly during bronchiectasis exacerbations. Clinical Trial registered with www.clinicaltrials.gov (NCT01761214).

Capsaicin cough sensitivity and the association with clinical parameters in bronchiectasis.

Background Cough hypersensitivity has been common among respiratory diseases. Objective To determine associations of capsaicin cough sensitivity and clinical parameters in adults with clinically stable bronchiectasis. Methods We recruited 135 consecutive adult bronchiectasis patients and 22 healthy subjects. History inquiry, sputum culture, spirometry, chest high-resolution computed tomography (HRCT), Leicester Cough Questionnaire scoring, Bronchiectasis Severity Index (BSI) assessment and capsaicin inhalation challenge were performed. Cough sensitivity was measured as the capsaicin concentration eliciting at least 2 (C2) and 5 coughs (C5). Results Despite significant overlap between healthy subjects and bronchiectasis patients, both C2 and C5 were significantly lower in the latter group (all P<0.01). Lower levels of C5 were associated with a longer duration of bronchiectasis symptoms, worse HRCT score, higher 24-hour sputum volume, BSI and sputum purulence score, and sputum culture positive for P. aeruginosa. Determinants associated with increased capsaicin cough sensitivity, defined as C5 being 62.5 µmol/L or less, encompassed female gender (OR: 3.25, 95%CI: 1.35–7.83, P<0.01), HRCT total score between 7–12 (OR: 2.57, 95%CI: 1.07–6.173, P = 0.04), BSI between 5–8 (OR: 4.05, 95%CI: 1.48–11.06, P<0.01) and 9 or greater (OR: 4.38, 95%CI: 1.48–12.93, P<0.01). Conclusion Capsaicin cough sensitivity is heightened in a subgroup of bronchiectasis patients and associated with the disease severity. Gender and disease severity, but not sputum purulence, are independent determinants of heightened capsaicin cough sensitivity. Current testing for cough sensitivity diagnosis may be limited because of overlap with healthy subjects but might provide an objective index for assessment of cough in future clinical trials.

Validation of the Mandarin Chinese version of the Leicester Cough Questionnaire in bronchiectasis

BACKGROUND The Leicester Cough Questionnaire (LCQ) has been validated for assessing cough-specific health status in bronchiectasis. We translated the LCQ into Mandarin Chinese and investigated its validity, reliability and responsiveness. METHODS The LCQ was translated into Mandarin Chinese using the forward-backward translation procedure. A total of 144 out-patients completed the Mandarin Chinese version of the LCQ (LCQ-MC), the Hospital Anxiety and Depression Scale (HADS) and the St Georges Respiratory Questionnaire. Reassessments were performed during exacerbations and at 6 months. Concurrent validation, internal consistency, repeatability and responsiveness were determined. RESULTS Minor cultural adaptations were made to the wording of LCQ-MC. No other difficulties were found during the translation process, with all items easily adapted to acceptable Mandarin Chinese. The questionnaire was not changed in terms of content layout and the order of the questions. In cognitive debriefing interviews, participants reported that the questionnaire was acceptable, relevant, comprehensive and easy to complete. The LCQ-MC showed good concurrent validity, internal consistency and test-retest reliability. Responsiveness was shown by significant changes in LCQ-MC scores between steady state, the first exacerbation and following 2-week antibiotic treatment (both interval changes, P < 0.01) CONCLUSION: The LCQ-MC is a valid, reliable and responsive instrument for determining cough-specific health status in Chinese bronchiectasis patients.

Unsupervised learning technique identifies bronchiectasis phenotypes with distinct clinical characteristics.

BACKGROUND Unsupervised learning technique allows researchers to identify different phenotypes of diseases with complex manifestations. OBJECTIVES To identify bronchiectasis phenotypes and characterise their clinical manifestations and prognosis. METHODS We conducted hierarchical cluster analysis to identify clusters that best distinguished clinical characteristics of bronchiectasis. Demographics, lung function, sputum bacteriology, aetiology, radiology, disease severity, quality-of-life, cough scale and capsaicin sensitivity, exercise tolerance, health care use and frequency of exacerbations were compared. RESULTS Data from 148 adults with stable bronchiectasis were analysed. Four clusters were identified. Cluster 1 (n = 69) consisted of the youngest patients with predominantly mild and idiopathic bronchiectasis with minor health care resource use. Patients in cluster 2 (n = 22), in which post-infectious bronchiectasis predominated, had the longest duration of symptoms, greater disease severity, poorer lung function, airway Pseudomonas aeruginosa colonisation and frequent health care resource use. Cluster 3 (n = 16) consisted of elderly patients with shorter duration of symptoms and mostly idiopathic bronchiectasis, and predominantly severe bronchiectasis. Cluster 4 (n = 41) constituted the most elderly patients with moderate disease severity. Clusters 2 and 3 tended to have a greater risk of bronchiectasis exacerbations (P = 0.06) than clusters 1 and 4. CONCLUSION Identification of distinct phenotypes will lead to greater insight into the characteristics and prognosis of bronchiectasis.

Sputum bacteriology in steady-state bronchiectasis in Guangzhou, China.

BACKGROUND The impact of potentially pathogenic micro-organisms (PPMs) on Chinese patients with steady-state bronchiectasis is unknown. METHODS Peripheral blood and sputum were sampled to determine inflammatory markers and sputum bacterial density. Spirometry and diffusing capacity were measured. Quality of life was assessed using the St Georges Respiratory Questionnaire. RESULTS Of 144 patients with steady-state bronchiectasis, Pseudomonas aeruginosa was isolated in 44 cases (30.6%). Compared with other PPMs, P. aeruginosa had a more pronounced influence on airway inflammation and spirometry, but not on systemic inflammation or quality of life. The impact of PPMs other than P. aeruginosa on clinical indices was similar. Bacterial density was not correlated with most clinical parameters. Factors associated with PPM isolation included bronchiectasis symptoms for ⩾ 10 years (OR 2.13) and ⩾ 4 bronchiectatic lobes (OR 2.82). Having ⩾ 4 exacerbations within 2 years (OR 2.18) and cystic bronchiectasis (OR 2.23) was associated with the colonisation of PPMs, i.e., isolating an identical PPM on at least two occasions within 1 year. CONCLUSION In patients with steady-state bronchiectasis in Guangzhou, P. aeruginosa is the most common organism causing heightened airway inflammation and poor lung function. PPM isolation or colonisation should be suspected in case of longer duration of symptoms, multilobar bronchiectasis, frequent exacerbation and cystic bronchiectasis.

Sleep Disturbances and Health-Related Quality of Life in Adults with Steady-State Bronchiectasis

Background Sleep disturbances are common in patients with chronic lung diseases, but little is known about the prevalence in patients with bronchiectasis. A cross sectional study was conducted to investigate the prevalence and determinants associated with sleep disturbances, and the correlation between sleep disturbances and quality of life (QoL) in adults with steady-state bronchiectasis. Methods One hundred and forty-four bronchiectasis patients and eighty healthy subjects were enrolled. Sleep disturbances, daytime sleepiness, and QoL were measured by utilizing the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and St. George Respiratory Questionnaire (SGRQ), respectively. Demographic, clinical indices, radiology, spirometry, bacteriology, anxiety and depression were also assessed. Results Adults with steady-state bronchiectasis had a higher prevalence of sleep disturbances (PSQI>5) (57% vs. 29%, P<0.001), but not daytime sleepiness (ESS≥10) (32% vs. 30%, P = 0.76), compared with healthy subjects. In the multivariate model, determinants associated with sleep disturbances in bronchiectasis patients included depression (OR, 10.09; 95% CI, 3.46–29.37; P<0.001), nocturnal cough (OR, 1.89; 95% CI, 1.13–3.18; P = 0.016), aging (OR, 1.04; 95% CI, 1.01–1.07; P = 0.009) and increased 24-hour sputum volume (OR, 2.01; 95% CI, 1.22–3.33; P = 0.006). Patients with sleep disturbances had more significantly impaired QoL affecting all domains than those without. Only 6.2% of patients reported using a sleep medication at least weekly. Conclusions In adults with steady-state bronchiectasis, sleep disturbances are more common than in healthy subjects and are related to poorer QoL. Determinants associated with sleep disturbances include depression, aging, nighttime cough and increased sputum volume. Assessment and intervention of sleep disturbances are warranted and may improve QoL.

Inflammatory Responses, Spirometry, and Quality of Life in Subjects With Bronchiectasis Exacerbations

BACKGROUND: Bronchiectasis exacerbations are critical events characterized by worsened symptoms and signs (ie, cough frequency, sputum volume, malaise). Objectives: Our goal was to examine variations in airway and systemic inflammation, spirometry, and quality of life during steady state, bronchiectasis exacerbations, and convalescence (1 week following a 2-week antibiotic treatment) to determine whether potentially pathogenic microorganisms, including Pseudomonas aeruginosa, were associated with poorer conditions during bronchiectasis exacerbations. METHODS: Peripheral blood and sputum were sampled to detect inflammatory mediators and bacterial densities. Spirometry and quality of life (St George Respiratory Questionnaire [SGRQ]) were assessed during the 3 stages. RESULTS: Forty-eight subjects with bronchiectasis (43.2 ± 14.2 y of age) were analyzed. No notable differences in species and density of potentially pathogenic microorganisms were found during bronchiectasis exacerbations. Except for CXCL8 and tumor necrosis factor alpha (TNF-α), serum inflammation was heightened during bronchiectasis exacerbations and recovered during convalescence. Even though sputum TNF-α was markedly higher during bronchiectasis exacerbations and remained heightened during convalescence, the variations in miscellaneous sputum markers were unremarkable. Bronchiectasis exacerbations were associated with notably higher SGRQ symptom and total scores, which recovered during convalescence. FVC, FEV1, and maximum mid-expiratory flow worsened during bronchiectasis exacerbations (median change from baseline of −2.2%, −0.8%, and −1.3%) and recovered during convalescence (median change from baseline of 0.6%, 0.7%, and −0.7%). Compared with no bacterial isolation, potentially pathogenic microorganism or P. aeruginosa isolation at baseline did not result in poorer clinical condition during bronchiectasis exacerbations. CONCLUSIONS: Bronchiectasis exacerbations are characterized by heightened inflammatory responses and poorer quality of life and spirometry, but not by increased bacterial density, which applies for subjects with and without potentially pathogenic microorganism isolation when clinically stable. (ClinicalTrials.gov registration NCT01761214.)

Sputum matrix metalloproteinase-8 and -9 and tissue inhibitor of metalloproteinase-1 in bronchiectasis: clinical correlates and prognostic implications.

The triplet of airway infection, inflammation and bronchial wall destruction associated with excessive matrix metalloproteinases (MMP) release and imbalance of tissue inhibitor metalloproteinase‐1 (TIMP‐1) is implicated in bronchiectasis. We sought to determine the associations between sputum MMP (MMP‐8, MMP‐9) and TIMP‐1 and the severity of bronchiectasis; the utility of MMP in predicting risks of future bronchiectasis exacerbations (BE); and the changes in MMP levels during BE.