Comparison of the 12-month impact of COVID-19 and SARS on physiological capacity and health-related quality of life.

BACKGROUND: Little is known about the differences in medium to long-term recovery on spirometry, 6-minute walking distance (6MWD) and health-related quality of life (HRQoL) between COVID-19 and SARS. METHODS: We performed a 12-month prospective study on COVID-19 survivors. The changes in dynamic lung volumes at spirometry (%predicted FEV1, %predicted FVC), 6MWD and HRQoL at 1-3, 6 to 12 months were compared against a historical cohort of SARS survivors using the same study protocol. The residual radiological changes in HRCT in COVID-19 survivors were correlated with their functional capacity. RESULTS: 108 COVID-19 survivors of various disease severity (asymptomatic 2.9%, mild 33.3%, moderate 47.2%, severe 8.3%, critical 8.3%) were recruited. When compared with 97 SARS survivors, 108 COVID-19 survivors were older (48.1 ± 16.4 vs. 36.1 ± 9.5 years, p < 0.001) and required less additional support during hospitalization; with lower dynamic lung volumes, shorter 6MWD and better physical component score. Both groups of survivors had comparable changes in these parameters at subsequent follow-ups. Both COVID-19 and SARS survivors had similar mental component score (MCS) at 6 and 12 months. COVID-19 survivors initially experienced less (between-group difference, -3.1, 95% confidence interval [CI] -5.5 to -0.7, p = 0.012) and then more improvement (between-group difference 2.9, 95%, CI 0.8 to 5.1, p = 0.007) than SARS survivors in the MCS at 1-3 to 6 months and 6 to 12 months respectively. Forty (44.0%) out of 91 COVID-19 survivors had residual abnormalities on HRCT at 12 months, with a negative correlation between the severity scores of parenchymal changes and 6MWD (r=-0.239, p < 0.05). CONCLUSIONS: COVID-19 survivors demonstrated a similar recovery speed in dynamic lung volumes and exercise capacity, but different paces of psychological recovery as SARS survivors in the convalescent phase. The severity of parenchymal changes in HRCT is negatively correlated with the 6MWD of COVID-19 survivors. TRIAL REGISTRATION: This prospective study was registered at ClinicalTrials.gov on 2 November 2020 (Identifier: NCT04611243).

Implementation of evidence on management of pleural diseases: insights from a territory-wide survey of clinicians in Hong Kong.

BACKGROUND: Major advances in management of common pleural diseases have taken place in the past decade. However, pleural diseases are often managed by physicians of diverse training background and research on implementation of new knowledge is scanty. We aim to evaluate the practice pattern in pleural medicine among physicians in Hong Kong, for identification of possible gaps for clinical service improvement. METHODS: The Hong Kong Thoracic Society undertook a cross-sectional questionnaire survey in 2019, targeting clinicians of various subspecialties in internal medicine and levels of experience (basic and higher trainees, specialists) from twelve regional hospitals of diverse service scopes throughout Hong Kong. Respondents were selected by non-probability quota sampling. The questionnaire tool consisted of 46 questions covering diagnostic and therapeutic aspects of common pleural diseases. The responses were anonymous, and analysed independently using SPSS statistics software. RESULTS: The survey collected 129 responses, 47(36%) were from clinicians specialized in respiratory medicine. Majority of the respondents (98%) managed pleural diseases, including performing pleural procedures in their practice. Fifty-five percent of all the respondents had not received any formal training in transthoracic ultrasonography. A significant proportion of clinicians were unaware of pleuroscopy for investigation of exudative pleural effusion, indwelling pleural catheter for recurrent malignant pleural effusion, and combined intra-pleural Alteplase plus DNase for treatment of pleural infection (30%, 15% and 70% of non-respiratory clinicians respectively). Significant heterogeneity was found in the management of pleural infection, malignant pleural effusion and pneumothorax among respiratory versus non-respiratory clinicians. Contributing factors to the observed heterogeneity included lack of awareness or training, limited accessibility of drugs, devices, or dedicated service support. CONCLUSION: Significant heterogeneity in management of pleural diseases was observed among medical clinicians in Hong Kong. Continuous medical education and training provision for both specialists and non-specialists has to be strengthened to enhance the implementation of advances, improve quality and equity of healthcare provision in pleural medicine.

Effect of short-course exercise training on the frequency of exacerbations and physical activity in patients with COPD: A randomized controlled trial.

BACKGROUND AND OBJECTIVE: Previous studies have suggested that early pulmonary rehabilitation (PR) programmes post-AECOPD are an effective and safe intervention for reducing hospital admissions and improving quality of life. This study assessed whether a short course of exercise training post-AECOPD with periodic reinforcement exercise training and phone call reminders reduces readmissions and increases physical activity in COPD patients. METHODS: Subjects were randomized into either the (i) intervention group (IG), consisting of 4-8 weeks of training supervised by a physiotherapist and phone contact every 2 weeks by a case manager providing support and reinforcement of continuous exercise at home or (ii) usual care group (UG), which had no input by a physiotherapist or case manager. Readmissions were assessed at 12 months. Activities of all patients were assessed by an activity monitor at baseline, 3 and 12 months. RESULTS: Altogether, 136 subjects were included and randomized (68 in IG and 68 in UG). The age, gender and FEV1 % predicted were 75.0 ± 6.7 years, 132 males and 47.0 ± 16.2%, respectively. The mean number of readmissions for AECOPD (1.06 vs 1.72 times, P = 0.014) was less and time to first readmission was increased (146.8 vs 122.4 days, P = 0.005) in the IG versus UG at 12 months. At 12 months, there was no change in activity measured by activity monitor between the two groups. CONCLUSION: This programme decreased exacerbation frequency and increased the time of readmissions for AECOPD. It did not improve physical activities and exercise tolerance at 12 months.

Blood eosinophil count as a predictor of hospital length of stay in COPD exacerbations.

BACKGROUND AND OBJECTIVE: Airway inflammation accompanying exacerbations varies among individuals with some having neutrophilic, while others showing eosinophilic inflammation. This study assessed the cut-off values of blood eosinophil count for identifying subjects with longer hospital length of stay (LOS) with acute exacerbations of chronic obstructive pulmonary disease (AECOPD). METHODS: Patients were recruited at presentation to the hospital with an AECOPD. Complete blood picture with differential count was taken on admission. Patients were treated with a standard course of systemic corticosteroid and antibiotic and evaluated at 8 weeks post-exacerbation for lung function measurement and 6-min walk. They were followed up in 1 year for any readmissions or mortality. Cut-off values of eosinophils for assessment of longer LOS were calculated using receiver operating characteristic (ROC) curve analysis. RESULTS: A total of 346 patients with admission eosinophil count were included in the analysis (333 (96.2%) were males; mean ± SD age: 74.9 ± 7.8 years; mean forced expiratory volume in 1 s (FEV1 ): 43.4 ± 16.3% predicted). The median (interquartile range (IQR)) of the absolute peripheral eosinophil count, percent eosinophil count and LOS were 0.11 (0.25) × 109 /L, 1 (3) % and 5 (7) days, respectively. Using the median LOS of ≥5 days as the cut-off, ROC analysis of the cut-off value of eosinophil count associated with longer LOS was at <2% (area under the curve (AUC): 0.666, P < 0.001) while absolute eosinophil count was at <0.144 × 109 /L (AUC: 0.645, P < 0.001). These eosinophil cut-off values could predict longer LOS independent of age, lung function and previous hospital admissions, but had no association with readmissions for AECOPD and mortality at 12 months. CONCLUSION: An eosinophil value of <0.144 × 109 /L on admission or <2% was associated with longer hospital LOS for AECOPD.

Effectiveness of a health-social partnership program for discharged non-frail older adults: a pilot study.

BACKGROUND: Previous studies supporting discharged patients are hospital-based which admission criteria tend to include mainly those with complex needs and/or specific disease conditions. This study captured the service gap where these non-frail older patients might have no specific medical problem upon discharge but they might encounter residual health and social issues when returning home. METHODS: Discharged community-dwelling non-frail older adults from an emergency medical ward were recruited and randomized into either intervention (n = 37) or control (n = 38) group. The intervention group received a 12-week complex interventions that included structured assessment, health education, goal empowerment, and care coordination supported by a health-social team. The control group received usual discharge care and monthly social call. The primary outcome was health-related quality of life (HRQoL). Secondary outcomes included activities of daily living (ADL), the presence of depressive symptoms, and the use of health services. The outcomes were measured at pre-intervention (T1) and at three months post-intervention (T2). The independent t-test or the Mann-Whitney U test was used to analyze the group differences in HRQoL, ADL, and presence of depressive symptoms according to the normality of data. RESULTS: Analysis showed that the intervention group experienced a statistically significantly improvement in the mental component scale of quality of life (p = .036), activities of daily living (p = .005), and presence of depressive symptoms (p = .035) at T2 compared with at T1. No significant differences were found in the control group. CONCLUSIONS: Supporting self-care is necessary to enable community-dwelling non-frail older adults to be independent to the fullest extent possible in the community. The promising results found in this pilot study suggested that the integration of the health-social partnership into transitional care practice is effective and can be sustained in the community. Future studies can draw on these findings and maximize the integrated care quality during the transition phase. TRIAL REGISTRATION: NCT04434742 (date: 17 June 2020, retrospectively registered).

Molecular detection of respiratory pathogens and typing of human rhinovirus of adults hospitalized for exacerbation of asthma and chronic obstructive pulmonary disease.

BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and asthma are associated with a variety of precipitating factors including infection. This study assessed the infective viral etiologies by real-time multiplex polymerase chain reaction of patients hospitalized with AECOPD and asthma exacerbations. In addition, infective etiologies were assessed for association with the clinical outcome of the patients. METHODS: Adults admitted with AECOPD and asthma exacerbations between August 2016 and July 2017 were recruited. Nasopharyngeal aspirate (NPA) samples were obtained from the patients within 1-2 days of admission and subjected to pathogen detection and human rhinovirus (HRV) typing. RESULTS: Altogether 402 patients with AECOPD, 80 stable COPD, 100 asthma exacerbation and 21 stable asthma subjects were recruited. Among those admitted for AECOPD and asthma exacerbations, 141(35.1%) and 45(45.0%) respectively had pathogens identified in the NPA specimens. The commonest virus identified was influenza A followed by HRV. HRV typing identified HRV-A and HRV-C as the more common HRV with a wide variety of genotypes. Identification of pathogens in NPA or HRV typing otherwise did not affect clinical outcomes including the hospital length of stay, readmission rates and mortality except that identification of pathogens in asthma exacerbation was associated with a lower rate of readmissions at 30 and 60 days. CONCLUSIONS: Many respiratory viruses were associated with AECOPD and asthma exacerbation. HRV-A and HRV-C were the more common HRV associated with exacerbations. Identification of pathogens in NPA was associated with less readmissions for asthma patients at 30 and 60 days. TRIAL REGISTRATION: ClinicalTrials.gov NCT02866357 .

Use of Berlin questionnaire in comparison to polysomnography and home sleep study in patients with obstructive sleep apnea.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is a common disorder with significant morbidity and mortality. We aimed to evaluate the predictive accuracy of the Berlin questionnaire in patients with suspected OSAS undergoing PSG in the sleep laboratory setting against those going through the Embletta™ portable diagnostic system (Embletta PDS) at home. METHODS: Patients with suspected OSAS were recruited from respiratory clinics to complete Berlin questionnaire and Epworth Sleepiness Score (ESS). Patients were randomized to undergo either home-based sleep test (group A) or hospital-based polysomnography (PSG) (group B). RESULTS: Three hundreds and sixteen subjects with newly referred suspected OSAS were recruited and randomized into group A (n = 157) and group B (n = 159). The prevalence of moderate to severe OSAS defined as apnea-hypopnea index (AHI) ≥ 15/h was 54%. The Berlin questionnaire identified 69.7% (n = 99) of subjects as high risk in group A and 77.5% (n = 100) in group B. The sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of the questionnaire to predict an AHI ≥ 15/h as diagnosed by PSG was 78, 23, 67 and 35%. When compared with Embletta PDS, the specificity and NPV increased to 48 and 63%. The area under the Receiver Operator Curve (ROC) based on PSG (AUC = 0.539, 95%CI 0.417, 0.661) and based on home Embletta (AUC = 0.712, 95%CI 0.617, 0.907). CONCLUSIONS: The questionnaire was not reliable in predicting OSAS through PSG AHI whereas there was some predictive ability in discriminating patients with OSAS from normal subjects based on home Embletta sleep test. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (Identifier: NCT01828216) on 10 April 2013.

Continuous positive airway pressure for obstructive sleep apnoea does not improve asthma control.

BACKGROUND AND OBJECTIVE: Unrecognized obstructive sleep apnoea syndrome (OSAS) may lead to poor asthma control despite optimal therapy. We assessed asthma control, airway responsiveness, daytime sleepiness and health status at baseline and 3 months after continuous positive airway pressure (CPAP) treatment among asthma patients with nocturnal symptoms and OSAS. METHODS: Patients with nocturnal asthma symptoms despite receiving at least moderate-dose inhaled corticosteroid and long-acting bronchodilators underwent a home sleep study using 'Embletta' portable diagnostic system. Patients with significant OSAS (apnoea-hypopnoea index (AHI) ≥10/h) were randomized to receive either CPAP or conservative treatment for 3 months. RESULTS: Among 145 patients recruited, 122 underwent sleep study with 41 (33.6%) having AHI ≥10/h. Patients with significant OSAS had higher BMI (27.4 (5.1) vs 25.1 (4.5) kg/m2 , P = 0.016), bigger neck circumference (36.6 (3.1) vs 34.8 (3.6) cm, P = 0.006) and lower minimum SaO2 (80.7 (6.6) vs 87.2 (3.9) %, P < 0.001). Using intention-to-treat analysis among 37 patients with AHI ≥10/h (CPAP group (n = 17) vs control group (n = 20)), there was no significant difference in Asthma Control Test score (CPAP 3.2 (2.7) vs control 2.4 (5.7), P = 0.568) but the CPAP group had a greater improvement in Epworth Sleepiness Scale (-3.0 (4.5) vs 0.5(3.8), P = 0.014), Asthma Quality of Life Questionnaire (0.6 (0.8) vs 0.02 (0.7), P = 0.022) and vitality domain in the SF-36 questionnaire (14.7 (16.8) vs 0.3 (16.2), P = 0.012) after 3 months. Data are presented as mean (SD) unless otherwise stated. CONCLUSION: A high prevalence of OSAS was found among patients with asthma and snoring. CPAP therapy for 3 months did not enhance asthma control but improved daytime sleepiness, quality of life and vitality.

Effects of CPAP therapy on visceral fat thickness, carotid intima-media thickness and adipokines in patients with obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Obstructive sleep apnoea (OSA) is associated with an increased prevalence of metabolic syndrome. This study explores the effects of continuous positive airway pressure (CPAP) for patients with OSA on visceral and mesenteric fat thickness, carotid intima-media thickness (IMT) and adipokines. METHODS: A randomized controlled study was conducted at a teaching hospital on 90 patients newly diagnosed with OSA to receive either therapeutic CPAP or subtherapeutic CPAP for 3 months. Visceral fat thickness and carotid IMT were measured with B-mode ultrasound; adipokine levels were assessed at baseline and 3 months. RESULTS: Altogether, 45 patients received therapeutic CPAP and 45 received subtherapeutic CPAP without significant differences in age 50.3 (10.1) versus 48.7 (9.0) years, BMI 28.2 (3.9) versus 28.2 (4.5) kg/m2 , Epworth Sleepiness Scale (ESS) 12.4 (5.9) versus 11.3 (4.7), apnoea-hypopnoea index (AHI) 30.6 (21.4) versus 35.2 (25.5) /h, minimum SaO2 79.6 (10.8) versus 76.7 (12.4) % and existing co-morbidities. CPAP usage was therapeutic 4.2 (2.1) versus subtherapeutic 4.1 (2.0) h/night over 3 months. Adiponectin and irisin levels changed significantly following therapeutic CPAP for 3 months versus subtherapeutic CPAP (-1.6 vs 7.3, P = 0.042; 0.1 vs -0.1, P = 0.028 respectively) while only serum level of monocyte chemotactic protein 1 (MCP-1) at baseline was positively correlated with AHI (r = 0.278). No significant changes were observed in other adipokines, visceral fat thickness and IMT. CONCLUSION: Short-term therapeutic CPAP versus subtherapeutic CPAP does not significantly reduce visceral fat thickness and IMT, although it reduces adiponectin and increases irisin.

Role of nasal positive end expiratory pressure valve as an alternative treatment for obstructive sleep apnoea in Chinese patients.

BACKGROUND AND OBJECTIVE: As compliance of continuous positive airway pressure (CPAP) for treatment of obstructive sleep apnoea (OSA) is often suboptimal, a less cumbersome treatment is desirable. We explored the clinical usefulness of nasal positive end expiratory pressure (nPEEP) valves. METHODS: Symptomatic OSA patients (apnoea hypopnea index (AHI) >5/h by polysomnography (PSG) or >10/h by type III devices), who declined CPAP, were recruited. A nPEEP valve was attached to each nostril before bed. After successful acclimatization for 1 week, treatment was continued for 4 weeks. The nPEEP valves provided expiratory resistance to build up PEEP. PSG was performed at week 4. RESULTS: Among 196 subjects, 46 (23%) failed acclimatization and 14 (7%) withdrew. Among the 120 patients with a valid PSG, 72 (60%) and 75 (63%) had >50% reduction in mean (standard deviation) overall AHI 26 (16)/h to 18 (18)/h and mean supine AHI 31 (19)/h to 11(16)/h, respectively, P < 0.001. Compared with responders, patients with <50% reduction in AHI had a higher mean overall AHI (30/h vs 23/h, P = 0.03), higher mean supine AHI (35/h vs 26/h, P = 0.04), more severe mean oxygen desaturation nadir (76.7% vs 82.7%, P < 0.01) and longer mean period of desaturation <90% SaO2 (7.7 vs 2.4, P = 0.02). Breathing discomfort and dry mouth were the most common side effects. Compared with a dental device, there was a larger mean reduction in supine AHI using nPEEP (29 (14)/h vs 16 (17)/h). CONCLUSION: nPEEP valves were useful in selected patients with mild or positional-related OSA.

Mesenteric fat thickness is associated with metabolic syndrome independently of Apnoea-Hypopnoea Index in subjects with obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Mesenteric fat thickness (MFT) was associated with metabolic syndrome (MetS) and obstructive sleep apnoea (OSA) in separate studies. This study aimed to assess whether the association of MFT with MetS was independent of OSA in subjects with suspected OSA. METHODS: Two hundred forty-two subjects (men: 181; women: 61) with suspected OSA underwent ultrasound examinations for measurements of mesenteric, subcutaneous and preperitoneal fat thicknesses after overnight polysomnography. Anthropometric measurements and metabolic risk profile were assessed. RESULTS: Two hundred twenty-one (91%) subjects were confirmed to have OSA with Apnoea-Hypopnoea Index (AHI) >5/h. MFT had significant correlation (P < 0.01) with AHI and most MetS components. In partial correlation with adjustment for AHI, MFT had significant correlation (P < 0.01) with most MetS components including fasting plasma glucose (r = 0.25), triglycerides (r = 0.24), HDL cholesterol (r = -0.29) and waist circumference (r = 0.56). In multivariate logistic regression with adjustments for the confounding variables including AHI, MFT was the only variable independently associated with MetS, with the odds ratio of 5.48 (95% CI: 1.5-20.0) for every 1 cm increase of MFT. When the subjects were subdivided into obese (BMI ≥ 27.5 kg/m(2) ) and non-obese (BMI < 27.5 kg/m(2) ) groups, the positive association of MFT with MetS persisted in the non-obese group only, with the odds ratio of 22 (95% CI 2.8-174.1) for every 1 cm increase of MFT. The AHI had significant association with MetS in male subjects only. CONCLUSION: MFT, rather than AHI, is the major independent determinant of MetS in subjects with suspected OSA, particularly in non-obese subjects. See Editorial, page 408.

Mesenteric fat thickness is associated with increased risk of obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: Mesenteric fat is a type of intraperitoneal adipose tissue draining into portal circulation. The objective of this study was to investigate the relationships between mesenteric fat thickness and obstructive sleep apnoea (OSA) in patients with suspected OSA. METHODS: One hundred forty-nine subjects (men: 114; women: 35) with suspected OSA underwent ultrasound examinations of mesenteric, preperitoneal and subcutaneous fat thickness after overnight polysomnography. Body mass index (BMI) and neck circumference were recorded. RESULTS: The subjects with OSA (n = 130, apnoea/hypopnoea index (AHI) >5/h) had greater neck circumference, higher BMI, and greater mesenteric and preperitoneal fat thickness than those without OSA (n = 19, AHI ≤ 5/h). There was positive correlation of AHI with mesenteric (r = 0.43, P < 0.001) and preperitoneal fat thickness (r = 0.3, P < 0.001), whereas no significant association was observed between AHI and subcutaneous fat thickness (r = 0.09, P = 0.27). On multivariate logistic regression, after adjustments for gender, age, BMI, neck circumference, and preperitoneal and subcutaneous fat thickness, the mesenteric fat thickness had a positive association with the presence of moderate OSA and severe OSA, with odds ratios of 7.18 and 7.45 for every 1 cm increase in mesenteric fat thickness when AHI was defined as ≥15/h and AHI ≥ 30/h, respectively. CONCLUSIONS: Mesenteric fat thickness is associated with increased risk of OSA, independent of other abdominal fat thickness, BMI and neck circumference. Sonographic measurement is potentially a useful tool for further evaluating the complex association of visceral fat, metabolic syndrome and OSA.

Digital Image Comparison of Cellular Yield in Bronchial Brushing: Pre- and Post-Biopsy Lavage Cytology.

INTRODUCTION: Bronchoscopy is a useful diagnostic tool capable of performing core biopsy, forceps biopsy, bronchoalveolar lavage, and bronchial brushing. This study compares the cellularity of bronchial cytology including pre- and post-biopsy lavage by digital image analysis, aiming to increase diagnostic and tumor yield by optimizing the sequence and combination of bronchial biopsy and cytology. METHODS: Alveolar macrophage, bronchial epithelium, and tumor cell cellularity from liquid-based cytology preparations of bronchial brushing and pre-biopsy and post-biopsy bronchoalveolar lavage were annotated on digitized whole-slide images and compared. Secondary analysis on the relationship of tumor cell and non-lesional cell yield was performed. RESULTS: Overall, 118 cytology specimens from 43 patients were retrieved in total. Bronchial epithelium count was higher in pre-biopsy than post-biopsy lavage (p < 0.01) but not for alveolar macrophages nor tumor cell (p > 0.05). Tumor cell count was higher for bronchial brushing cytology samples than lavage (p = 0.018). The alveolar macrophage count was higher in post-biopsy lavage than bronchial brushing (p = 0.033); otherwise, brushing showed consistently higher bronchial epithelium and tumor cell counts. There were 33 false negative (tumor cell absent) specimens, and the combination of bronchial brushing and pre-biopsy lavage yielded the lowest false negative cases. Correlation between bronchial epithelium and alveolar macrophage counts with tumor cell count was weak (correlation coefficient = -0.168-0.203) except for post-biopsy lavage (correlation coefficient = 0.412-0.479, p < 0.05). CONCLUSION: Bronchial brushing yields a greater amount of tumor cell than lavage, and timing lavage before or after core biopsy does not affect tumor cell yield. Combining bronchial brushing and pre-biopsy lavage results in the lowest false negative rate.

Pneumomediastinum and subcutaneous emphysema complicating a patient with a lung abscess.

Pneumomediastinum and subcutaneous emphysema are conditions that carry significant morbidity. They are uncommonly seen as complications of lung abscess formation and prompt recognition and treatment is necessary. We present a 59-year-old male patient who complained of shortness of breath and chest pain for 2 weeks. Computed tomography (CT) of the thorax showed a left lower lobe lung abscess. This was associated with leucocytosis and raised C-reactive protein. Ultrasound-guided drainage revealed viscous pus requiring manual aspiration for adequate drainage. The patient later developed extensive pneumomediastinum and subcutaneous emphysema involving the pretracheal space, without evidence of pneumothorax. Left lower lobectomy was performed to control sepsis. The patient achieved a complete recovery following his surgery and antibiotic treatment, with interval resolution of pneumomediastinum and subcutaneous emphysema. We present the radiological and clinical features leading to the diagnosis of pneumomediastinum and subcutaneous emphysema.

1-Year Prospective Study of the Relationship of Serial Exhaled Nitric Oxide Level and Asthma Control.

Background and Objective: Previous studies found that the fractional nitric oxide concentration in exhaled breath (FeNO) levels in healthy Chinese adults was higher than in White adults. More understanding of serial changes of FeNO levels with asthma control in a real-life clinical setting would be important to explore the utility of this biomarker in routine asthma management. This study assessed the FeNO levels of Chinese asthma subjects with different levels of asthma control and the serial changes with respect to the changes in asthma control over 1 year. Methods: A 12-month prospective study (subjects recruited between November 2019 and January 2021) with serial measurement of FeNO levels at baseline, 4, 8 and 12 months. Asthma control was assessed by the Global Initiative for Asthma classification, Asthma Control Test (ACT) and Asthma Control Questionnaire (ACQ). Results: Altogether, 136 subjects (mean age 51.51±15.09 years, 46[33.8%] male) had successful baseline FeNO measurements. At baseline, the FeNO levels did not show a statistically significant difference for controlled, partly controlled and uncontrolled asthma according to GINA classification, ACT and ACQ. FeNO levels decreased with improving asthma control and stayed at similar levels with unchanged or worsening asthma control for all subjects. For subjects with baseline blood eosinophil levels ≥300 cells/µL(n=59), FeNO levels decreased with improving asthma control, stayed similar without change for asthma control and increased with worsening asthma control. Receiver operating characteristic (ROC) analysis with the highest area under curve (AUC) for changes in FeNO levels for improving asthma control was between ≤ -10 to -25 ppb at various time points in the 12-month study. Conclusion: Changes in FeNO levels over time were associated with changes in clinical asthma control, particularly in those with higher blood eosinophil count and are likely more useful than a single time point measurement in managing asthma.

Phenotyping empyema by pleural fluid culture results and macroscopic appearance: an 8-year retrospective study.

Background: The clinical impact of phenotyping empyema is poorly described. This study was designed to evaluate clinical characteristics and outcomes based on the two readily available parameters, pleural fluid culture status and macroscopic fluid appearance. Methods: A retrospective study was conducted on patients with empyema hospitalised between 2013 and 2020. Empyema was classified into culture-positive empyema (CPE) or culture-negative empyema (CNE) and pus-appearing empyema (PAE) or non-pus-appearing empyema (non-PAE) based on the pleural fluid culture status and macroscopic fluid appearance, respectively. Results: Altogether, 212 patients had confirmed empyema (CPE: n=188, CNE: n=24; PAE: n=118, non-PAE: n=94). The cohort was predominantly male (n=163, 76.9%) with a mean age of 65.0±13.6 years. Most patients (n=180, 84.9%) had at least one comorbidity. Patients with CPE had higher rates of in-hospital mortality (19.1% versus 0.0%, p=0.017) and 90-day mortality (18.6% versus 0.0%, p=0.017) and more extrapulmonary sources of infection (29.8% versus 8.3%, p=0.026) when compared with patients with CNE. No significant difference in mortality rate was found between PAE and non-PAE during the in-hospital stay and at 30 days and 90 days. Patients with PAE had less extrapulmonary sources of infection (20.3% versus 36.2%, p=0.010) and more anaerobic infection (40.9% versus 24.5%, p=0.017) than those with non-PAE. The median RAPID (renal, age, purulence, infection source, and dietary factors) scores were higher in the CPE and non-PAE groups. After adjusting for covariates, culture positivity was not independently associated with mortality on multivariable analysis. Conclusion: Empyema is a heterogeneous disease with different clinical characteristics. Phenotyping empyema into different subclasses based on pleural fluid microbiological results and macroscopic fluid appearance provides insight into the underlying bacteriology, source of infection and subsequent clinical outcomes.

A prospective cohort study of the long-term effects of CPAP on carotid artery intima-media thickness in obstructive sleep apnea syndrome.

OBJECTIVE: To examine the long-term effect of CPAP on carotid artery intima-media thickness (IMT) in patients with Obstructive sleep apnea syndrome(OSAS). METHODS: A prospective observational study over 12 months at a teaching hospital on 50 patients newly diagnosed with OSAS who received CPAP or conservative treatment (CT). Carotid IMT was assessed with B-mode Doppler ultrasound from both carotid arteries using images of the far wall of the distal 10 mm of the common carotid arteries at baseline, 6 months and 12 months. MEASUREMENTS AND RESULTS [MEAN (SE)]: Altogether 28 and 22 patients received CPAP and CT respectively without significant differences in age 48.8(1.8) vs 50.5(2.0)yrs, BMI 28.2(0.7) vs 28.0(1.2)kg/m2, ESS 13.1(0.7) vs 12.7(0.6), AHI 38(3) vs 39(3)/hr, arousal index 29(2) vs 29(2)/hr, minimum SaO2 75(2) vs 77(2)% and existing co-morbidities. CPAP usage was 4.6(0.3) and 4.7(0.4)hrs/night over 6 months and 1 year respectively. Carotid artery IMT at baseline, 6 months, and 12 months were 758(30), 721(20), and 705(20)micron for the CPAP group versus 760(30), 770(30), and 778(30)micron respectively for the CT group, p = 0.002. Among those free of cardiovascular disease(n = 24), the carotid artery IMT at baseline, 6 months and 12 months were 722(40), 691(40), and 659(30)micron for the CPAP group (n = 12) with usage 4.5(0.7) and 4.7(0.7) hrs/night over 6 months and 12 months whereas the IMT data for the CT group(n = 12) were 660(20), 685(10), and 690(20)micron respectively, p = 0.006. CONCLUSIONS: Reduction of carotid artery IMT occurred mostly in the first 6 months and was sustained at 12 months in patients with reasonable CPAP compliance.

Evaluation of the asthma control test: a reliable determinant of disease stability and a predictor of future exacerbations.

BACKGROUND AND OBJECTIVE: This study assessed the asthma control test (ACT) cut-off values for asthma control according to the Global Initiative for Asthma guideline in adults and the effectiveness of ACT scores in predicting exacerbations and serial changes in ACT scores over time in relation to treatment decisions. METHODS: Subjects completed ACT together with same-day spirometry and fractional concentration of exhaled nitric oxide (FeNO) measurement at baseline and at 3 months. Physicians, blinded to the ACT scores and FeNO values, assessed the patient's asthma control in the past month and adjusted the asthma medications according to management guidelines. Asthma exacerbations and urgent health-care utilization (HCU) at 6 months were recorded. RESULTS: Three hundred seventy-nine (120 men) asthmatics completed the study. The ACT cut-off for uncontrolled and partly controlled asthma were ≤19 (sensitivity 0.74, specificity 0.67, % correctly classified 69.5) and ≤22, respectively (sensitivity 0.73, specificity 0.71, % correctly classified 72.1). Baseline ACT score had an odds ratio of 2.34 (95% confidence interval: 1.48-3.69) and 2.66 (1.70-4.18) for urgent HCU and exacerbations, respectively, at 6 months (P < 0.0001). However, baseline FeNO and spirometry values had no association with urgent HCU and exacerbations. The 3-month ACT score of ≤20 correlated best with step-up of asthma medications (sensitivity 0.65, specificity 0.81, % correctly classified 72.8). For serial changes of ACT scores over 3 months, the cut-off value was best at ≤3 for treatment decisions with low sensitivity (0.23) and % correctly classified (57.3%) values. CONCLUSIONS: Single measurement of ACT is useful for assessing asthma control, prediction of exacerbation and changes in treatment decisions.

Effect of early pulmonary rehabilitation on health care utilization and health status in patients hospitalized with acute exacerbations of COPD.

BACKGROUND AND OBJECTIVE: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) incur heavy utilization of health-care resources for patients who require hospitalization. We evaluated whether an early outpatient pulmonary rehabilitation programme (PRP) after hospitalization for AECOPD could reduce acute health-care utilization over the succeeding year. METHODS: Sixty patients admitted with AECOPD were randomized to either PRP or usual care (UC). The PRP group received 8weeks of outpatient rehabilitation programme 2-3weeks after discharge from hospital. Lung function, 6min walk test and dyspnoea score were assessed at baseline, 3, 6, 9 and 12months, while St George's respiratory questionnaire and cardiopulmonary exercise test were assessed at baseline, 3, 6 and 12months. RESULTS: The PRP and UC groups demonstrated a 53.3% and 43.3% risk of readmissions at 12months (incident risk ratio 0.97 (95% CI: 0.57-1.60), P=0.90). The mean readmission rates were 1.00±1.20 and 1.03±1.87 (P=0.47) for the PRP versus UC groups respectively. The rates of AECOPD and emergency department visits were similar between the two groups. The St George's respiratory questionnaire total score was lower in the PRP group (40.15±19.10 vs 46.91±18.21, P=0.01 and 42.3±20.06 vs 51.44±18.98 P=0.01 at 3 and 6months respectively). There were no statistically significant differences in the FEV(1) % predicted, dyspnoea score, 6min walk test and maximal oxygen consumption during exercise test between PRP and UC at different time points. CONCLUSIONS: An early rehabilitation programme following AECOPD led to improvement in quality of life up to 6months, but did not reduce health-care utilization at 1year.