BMJ Open Respiratory Research最新文献

Background: Bronchiectasis is a respiratory disease structurally characterised by irreversible airway dilatation. Functional impairments are also implicated in bronchiectasis, but the detailed changes in pulmonary function and the impact of clinical factors are yet to be examined. We analysed pulmonary function in patients with bronchiectasis based on their clinical features.

Methods: Two study cohorts-a multicentre bronchiectasis registry and health check-up examinees-were analysed. Airflow limitation was defined as forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) <0.7, and bronchiectasis severity was categorised using the number of involved lobes.

Results: Among 13 589 health check-up examinees, 606 (4.5%) had bronchiectasis; airflow limitation was more prevalent in those with bronchiectasis than in those without (17.3% vs 8.1%, p<0.001). Ever-smokers with bronchiectasis had the lowest FEV₁, FEV₁/FVC and FVC values, and the highest prevalence of airflow limitation. In the bronchiectasis registry (n=768), lung function parameters were worse in those with more involved lobes and Pseudomonas colonisation. Multivariable logistic regression analysis showed that bronchiectasis was independently associated with airflow limitation (OR 2.22 (95% CI 1.75 to 2.82)).

Conclusions: Bronchiectasis is an independent risk factor for airflow limitation, and disease severity, smoking and Pseudomonas colonisation were each associated with worsening in pulmonary function.

Introduction: As the population ages, informal carers play an increasingly essential role in supporting patients with chronic respiratory diseases (CRDs), often at the expense of their own health. While the psychological effects are well documented, less is currently known about the physical toll of caregiving. Some trials have shown promising outcomes from pulmonary rehabilitation (PR) interventions targeting both patients and informal carers, but study designs have been limited. This trial aims to better understand informal carers' experience by assessing their physical, psychological and social well-being at home, before and after the individual they care for participates in either a home-based or centre-based PR programme.

Methods and analyses: This is a multicentre, convergent parallel mixed-methods study using a before-and-after intervention design. 54 informal carers of patients with CRDs will be recruited from two PR services-27 from a home- and 27 from a centre-based programme. Assessments of the physical, psychological and social well-being of the informal carers will be conducted at home. Semistructured interviews, conducted within 2-weeks post-PR, will explore informal carers' expectations, experiences and support needs. The home-based PR programme will involve weekly 90-min sessions for 8 weeks, supervised at home by a care manager. Informal carers will have the opportunity to participate in PR sessions in accordance with their needs, availability and patient preferences. At the centre-based PR site, patients with CRDs will be enrolled in a 4-week inpatient PR programme or in a 5- to 10-week outpatient PR programme, consisting of 2 or 4 supervised sessions per week (for a total of 20 supervised sessions). Informal carers' attendance will be tracked at both sites.

Ethics and dissemination: Ethical approval was obtained from the University Sud Mediterranean 3 (24.04596.000457;2024/10/07). The trial results will be presented at scientific conferences, submitted to peer-reviewed journals and shared with decision-makers.

Trial registration number: NCT06832709.

Objective: To characterise the allergen sensitisation profile and its demographic, seasonal and laboratory associations in children with allergic rhinitis (AR) and/or asthma in Guangdong, China.

Methods: We retrospectively reviewed the records of children diagnosed with AR and/or asthma from January 2020 to December 2023. Serum allergen-specific Immunoglobulin E (IgE) measurements were used to identify allergens. Sensitisation patterns and their relationships with age, sex, season of visit, peripheral-blood cell counts and immune markers were assessed with χ² tests and Spearman correlation.

Results: A total of 8080 children (median age, 7.0 years; 69.0% boys) were included; 89.1% had AR, 7.5% asthma and 3.4% both conditions. Overall, 76.5% were sensitised to inhalant allergens, 18.3% to food allergens and 5.2% to other allergens. Dermatophagoides farinae (93.2 %) and Dermatophagoides pteronyssinus (88.3 %) were the dominant inhalant allergens, whereas egg (14.2 %) and milk (11.9 %) prevailed among foods. Dual sensitisation was most common (67.6 %). Inhalant sensitisation peaked in summer (79.8 %), whereas food sensitisation was highest in spring (6.8 %). Inhalant-allergen positivity increased with age, while food-allergen positivity declined (p<0.001). Seventeen of 18 allergens displayed significant sex differences. Total IgE correlated positively with most inhalant and food allergens but negatively with egg allergen (p<0.05); neutrophil percentage showed similar positive correlations with several allergens. Allergen sensitisation correlates with impaired lung function and elevated airway inflammation.

Conclusion: House-dust mites are the principal sensitising allergens in children with AR and/or asthma in Guangdong, followed by egg and milk. Sensitisation patterns are modulated by season, age and sex, underscoring the necessity for region- and age-specific preventive and therapeutic strategies in paediatric allergic disease management.

Background: Limited contemporary epidemiological data exist for asthma among school-aged adolescents in Togo. This study aimed to estimate the prevalence of asthma among Togolese adolescents in Grand-Lomé (an urbanised region in the south) and Kara (a more rural area in the north). Furthermore, we explored demographics and risk factors associated with asthma diagnoses, with specific emphasis on the role of adverse childhood experiences (ACEs).

Methods: A cross-sectional study was conducted in secondary schools across southern and northern regions of Togo between February and March 2025. Adolescents aged 10-19 years were enrolled using multistage stratified random sampling. Asthma screening utilised International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires and spirometry with reversibility testing. ACEs were assessed using ACE-Q. A multilevel mixed-effects penalised binary logistic regression model identified factors associated with asthma.

Results: Among 2416 adolescents included in final analysis, median age was 16.0 years (IQR: 14.0-17.0), with 55.4% female. Overall asthma prevalence was 8.7% (95% CI: 7.6 to 9.9), with higher rates in the southern region (10.5%) compared with northern region (5.9%) (p<0.001). High childhood adversity (adjusted OR (aOR)=1.79; 95% CI: 1.09 to 2.94) was associated with asthma. Other factors significantly associated with asthma included: parental history of asthma (aOR=2.87; 95% CI: 2.03 to 4.05), and overweight/obesity (aOR=1.81; 95% CI: 1.22 to 2.68). Older age (aOR=0.93; 95% CI: 0.87 to 0.99) and male gender (aOR=0.67; 95% CI: 0.48 to 0.93) were associated with lower asthma likelihood.

Conclusion: Asthma prevalence among school-going adolescents in Togo is substantial and shows marked regional variation. Beyond established risk factors, the observed association with ACEs supports the need for integrated strategies addressing both physical and psychosocial determinants and for strengthening school-based surveillance and care pathways.

Background: Chronic obstructive pulmonary disease (COPD) is a heterogeneous condition whose clinical severity may be influenced by social factors. We aimed to identify distinct COPD clinical phenotypes and assess variation by social determinants of health.

Methods: In this retrospective cohort study, we identified adults aged 50-80 years with a diagnosis of COPD (n=59 797) at a tertiary academic medical centre in North-Central Florida using codes from International Classification of Diseases. Latent class analysis defined COPD clinical phenotypes using indicators of clinical severity, including frequency of acute care encounters (urgent care, emergency department visits and hospitalisations), presence of COPD as the principal diagnosis, comorbidity burden and use of Global Initiative for Chronic Obstructive Lung Disease Group D medications. Kaplan-Meier survival curves and Cox proportional hazards models assessed mortality across phenotypes. Multinomial logistic regression models estimated associations between phenotype membership and race/ethnicity, income, rurality and smoking status, using the minimal phenotype as reference.

Results: Five clinical phenotypes were identified: minimal (20.9%), mild (35.2%), moderate (22.5%), severe (12.2%) and very severe (9.3%). The very severe phenotype had the highest mortality (adjusted HR 2.94; 95% CI 2.72 to 3.18). Odds of very severe COPD were higher among non-Hispanic Black (adjusted OR (aOR) 1.29; 95% CI 1.21 to 1.36) and Hispanic individuals (aOR 1.75; 95% CI 1.63 to 1.87), those in the lowest income communities (aOR 1.25; 95% CI 1.18 to 1.32), rural residents (aOR 1.80; 95% CI 1.68 to 1.92) and individuals who currently smoke (aOR 1.30; 95% CI 1.20 to 1.42).

Conclusion: Most patients with COPD had mild disease; however, the very severe phenotype, which was associated with higher mortality, was more common among Black and Hispanic individuals, those residing in lower-income and rural areas and those who currently smoke. These clinical phenotypes highlight sociodemographic differences in COPD severity as reflected in healthcare utilisation and outcomes.

Introduction: Preventable morbidity and mortality from chronic obstructive pulmonary disease (COPD) accrue from major adverse cardiovascular events (MACEs) and acute exacerbations of COPD (AECOPD). The study aims to summarise models for the prediction of these cardiopulmonary events in community-based settings.

Methods: We searched for studies of multivariable models derived, validated or augmented for the prediction of cardiopulmonary events in COPD and used community-based data sources using MEDLINE and Embase from inception through 10 April 2025. Discrimination measures for the model with C-statistic data from ≥3 cohorts were pooled by Bayesian meta-analysis, and heterogeneity and risk of bias assessments were undertaken.

Results: No models were identified that predicted cardiopulmonary events in COPD using community-based data. Of the 71 models included, 5 predicted cardiovascular events, 32 predicted AECOPD and 30 predicted all-cause mortality. None were eligible for meta-analysis for the prediction of cardiovascular events or AECOPD. For all-cause mortality, age, dyspnoea and airflow obstruction-surprise question (ADO-SQ) (0.763, 95% CI 0.533 to 0.942) and body mass index, airflow obstruction, dyspnoea score and exercise capacity (BODE) (0.753, 95% CI 0.583 to 0.907) demonstrated good prediction performance, while ADO (0.638, 95% CI 0.443 to 0.827) demonstrated adequate prediction performance. The risk of bias was high for 57.9% of studies, and none had clinical utility evaluated.

Conclusions: Despite the high burden of MACE and AECOPD, there is an absence of community-based models that predict this composite outcome. Models to identify individuals with COPD at high risk of cardiopulmonary events could enable targeted clinical intervention.

Prospero registration number: CRD420251026275.

Background: Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is heterogeneous. Forced vital capacity (FVC) decline and high-resolution CT (HRCT) pattern are widely used as prognostic markers, but the natural history of RA-ILD identified in rheumatology clinics, particularly in mild disease, remains insufficiently described.

Methods: We conducted a prospective, multicentre cohort study across three Brazilian centres. Adults with RA-ILD were followed every 6 months for 24 months. Pulmonary function tests, HRCT, 6 min walk test and King's Brief Interstitial Lung Disease health-related quality-of-life questionnaire were performed at baseline, 12 and 24 months. Blood biomarkers were assessed at baseline, 6 and 18 months. HRCT scans were independently reviewed by two chest radiologists and analysed using densitometry-based quantitative CT (QCT). Pulmonary fibrosis was qualitatively defined by unequivocal traction bronchiectasis and/or honeycombing on HRCT.

Results: Ninety-five subjects were included (mean age 63±10 years; 81% female). Pulmonary fibrosis was present in 80%, although only 20% were classified as definite or probable usual interstitial pneumonia (κ=0.52). Individuals with fibrosis had lower FVC (75%±17 vs 86%±15, p=0.02) and worse QCT measures (%high-attenuation areas -600 to -250 HU 12.1±6.6 vs 5.5±0.8, p<0.001; lung volume 3407±958 mL vs 4077±923 mL, p=0.015). In 24 months, FVC and QCT measures remained stable. Eight subjects (8%) died. Deaths were not preceded by measurable functional or radiological decline. Health-related quality-of-life scores and blood biomarkers remained unchanged.

Conclusions: In this predominantly mild RA-ILD cohort, pulmonary function and QCT metrics remained stable over 2 years despite an 8% mortality rate. The absence of preceding decline in conventional prognostic markers suggests potential limitations of current monitoring strategies, although our findings should be interpreted as hypothesis-generating.

Trial registration number: NCT04136223.

Background: Chronic obstructive pulmonary disease (COPD) in never-smokers may have other clinical characteristics than tobacco smoking-related COPD.

Research question: What are the risk factors, biomarkers, respiratory symptoms and health status in never-smoking individuals with COPD?

Study design and methods: We investigated never-smokers with COPD (n=154, mean age 60 years) from the population-based Swedish CArdioPulmonary bioImage Study (SCAPIS), and compared them with four control groups: never-smokers with normal lung function (n=281), current smokers with normal lung function (n=97), ex-smokers with COPD (n=103) and current smokers with COPD (n=55). COPD was defined as forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) less than the lower limit of normal (LNN) after bronchodilation. We examined fractional exhaled nitric oxide (FeNO), blood biomarkers, respiratory symptoms, health status, medical history and living conditions.

Results: The never-smoker COPD group reported more respiratory symptoms and worse health status than never-smokers with normal lung function, but fewer symptoms, milder airflow limitation and better health status compared with ex-smokers and smokers with COPD. Never-smokers with COPD had more self-reported asthma. Moreover, never-smokers with COPD had higher Immunoglobulin E sensitisations to a mix of aeroallergens, higher geometrical mean FeNO levels and blood eosinophil counts than never-smokers with normal lung function. When participants with self-reported asthma were excluded, never-smokers with COPD still had more wheeze, cough and higher FeNO.

Conclusion: Never-smokers with COPD had more respiratory symptoms and elevated markers of type-2 inflammation, suggesting they might represent a distinct clinical phenotype which may differ from smoking-related COPD. They may therefore need to be treated and followed differently.

Trial registration number: NCT03049202.

Background: Tuberculosis (TB) survivors experience high mortality and long-term morbidity, contributing substantially to the global TB burden. In the UK, where TB incidence is rising, the scale of post-TB health needs is unknown and current guidelines do not recommend follow-up. We conducted the first nationwide survey of UK TB services to assess approaches to post-TB care.

Methods: We conducted a digital survey between February and May 2025 across National Health Service TB services in all four nations, targeting specialist clinicians. The questionnaire captured data on types of post-TB morbidity encountered and current practice. We analysed descriptively and stratified by caseload.

Results: We received responses from 113 of 135 TB services (84%). Most respondents were lead clinicians (81%), and nearly all (96%) had encountered post-TB morbidity in their patient populations, including lung disease (82%), social vulnerabilities (79%), and financial issues (66%). High caseload services (≥30 cases/year) reported more types of morbidity (mean 4.2 vs 2.9; p<0.001). While end of treatment symptom screening and chest X-rays are routine (>95%), fewer than half of services perform assessments for broader post-TB sequelae and comorbidities, or provide direct ongoing medical care (41%). Most services cited staffing (78%), clinic capacity (70%) and funding (59%) as challenges to post-TB care.

Conclusions: A high proportion of UK TB clinicians recognise post-TB morbidity among their patient groups. TB services are introducing elements of post-TB care, but provision is heterogenous and often informal, with multiple resource-related challenges. Robust UK-specific data, stakeholder engagement and clear guidance are needed to support post-TB care pathways.

Rationale: Identifying patients who could be safely managed at home versus those needing hospitalisation was a particular concern during early COVID-19. Respiratory viruses remain a concern, including new COVID-19 variants, influenza and respiratory syncytial virus. We developed COVIDFree@Home, a mobile application and clinician dashboard for remote monitoring, to determine if remotely collected measures could predict low oxygen saturation in home-isolating patients with COVID-19.

Methods: We conducted a prospective cohort study of patients newly diagnosed with COVID-19 from three Toronto hospitals between 2020 and 2022. Participants used the COVIDFree@Home app daily to enter symptoms, temperature, heart rate and oxygen saturation at home, which clinicians monitored via an online dashboard. We analysed baseline characteristics and remote monitoring variables to identify predictors of oxygen saturation ≤92%. A random forest classifier was trained to predict low oxygen saturation in the following 2 days. A secondary objective was to identify factors predicting hospitalisation.

Results: Of 431 participants, 376 (87.2%) entered at least one measure. Of the 376, 49 (13%) experienced low oxygen saturation, and 19 (5.1%) were hospitalised. Baseline factors associated with low oxygen saturation included older age, obesity, pre-existing pulmonary disease and Alpha/Beta variant. The classifier predicted future low oxygen saturation with an area under the curve of 0.68 (sensitivity 57%, specificity 72%, positive predictive value 3%, negative predictive value 99%). Key predictive factors included cough, lower baseline oxygen saturation, severe fatigue, higher temperature and higher heart rate. Factors associated with hospitalisation included dyspnoea, fever, Alpha/Beta variant and comorbidities of hypertension, mental illness and diabetes. Patients with a runny nose or sore throat were less likely to be hospitalised.

Conclusions: During the COVID-19 pandemic, remote monitoring along with knowledge of baseline characteristics could predict low oxygen saturation in the next 2 days in people with COVID-19. This approach may help identify individuals needing medical attention during future pandemics, though further model improvement is necessary.

Trial registration number: NCT04453774.