The impact of obstructive sleep apnea treatment on microvascular complications in patients with type 2 diabetes: a feasibility randomized controlled trial.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is associated with an increased risk of diabetes-related complications. Hence, it is plausible that Continuous Positive Airway Pressure (CPAP) could have a favorable impact on these complications. To assess the feasibility of conducting a randomized control trial (RCT) in patients with type 2 diabetes (T2D) and OSA over 2 years. METHODS: An open-label multicenter feasibility RCT of CPAP vs no CPAP in patients with T2D and OSA. Patients with resting oxygen saturation <90%, central apnea index >15/hour or Epworth Sleepiness Scale (ESS) ≥11 were excluded. OSA was diagnosed using a multichannel portable device (ApneaLink Air, ResMed). The primary outcome measures were related to feasibility, and the secondary outcomes were changes in various clinical and biochemical parameters related to diabetes outcomes. RESULTS: Eighty-three (40 CPAP vs 43 no CPAP) patients were randomized, with a median (IQR) follow-up of 645 [545, 861] days. CPAP compliance was inadequate, with a median usage of approximately 3.5 hours/night. Early CPAP use predicted longer-term compliance. The adjusted analysis showed a possible favorable association between being randomized to CPAP and several diabetes-related endpoints (chronic kidney disease (CKD), neuropathy, and quality of life (QoL)). CONCLUSIONS: It was feasible to recruit, randomize, and achieve a high follow-up rate over 2 years in patients with OSA and T2D. CPAP compliance might improve by a run-in period before randomization. A full RCT is necessary to assess the observed favorable association between CPAP and CKD, neuropathy, and QoL in patients with T2D. CLINICAL TRIAL REGISTRATION: Registry: ISRCTN; URL: https://www.isrctn.com/ISRCTN12361838; Title: The impact of sleep disorders in patients with type 2 diabetes; Identifier: ISRCTN12361838.

Engaging stakeholders to level up COPD care in LMICs: lessons learned from the "Breathe Well" programme in Brazil, China, Georgia, and North Macedonia.

BACKGROUND: Effective stakeholder engagement in health research is increasingly being recognised and promoted as an important pathway to closing the gap between knowledge production and its use in health systems. However, little is known about its process and impacts, particularly in low-and middle-income countries. This opinion piece draws on the stakeholder engagement experiences from a global health research programme on Chronic Obstructive Pulmonary Disease (COPD) led by clinician researchers in Brazil, China, Georgia and North Macedonia, and presents the process, outcomes and lessons learned. MAIN BODY: Each country team was supported with an overarching engagement protocol and mentored to develop a tailored plan. Patient involvement in research was previously limited in all countries, requiring intensive efforts through personal communication, meetings, advisory groups and social media. Accredited training programmes were effective incentives for participation from healthcare providers; and aligning research findings with competing policy priorities enabled interest and dialogue with decision-makers. The COVID-19 pandemic severely limited possibilities for planned engagement, although remote methods were used where possible. Planned and persistent engagement contributed to shared knowledge and commitment to change, including raised patient and public awareness about COPD, improved skills and practice of healthcare providers, increased interest and support from clinical leaders, and dialogue for integrating COPD services into national policy and practice. CONCLUSION: Stakeholder engagement enabled relevant local actors to produce and utilise knowledge for small wins such as improving day-to-day practice and for long-term goals of equitable access to COPD care. For it to be successful and sustained, stakeholder engagement needs to be valued and integrated throughout the research and knowledge generation process, complete with dedicated resources, contextualised and flexible planning, and commitment.

Randomised controlled trial testing effectiveness of feedback about lung age or exhaled CO combined with very brief advice for smoking cessation compared to very brief advice alone in North Macedonia: findings from the Breathe Well group.

INTRODUCTION: In 2019, smoking prevalence in North Macedonia was one of the world's highest at around 46% in adults. However, access to smoking cessation treatment is limited and no co-ordinated smoking cessation programmes are provided in primary care. METHODS: We conducted a three parallel-armed randomised controlled trial (n = 1368) to investigate effectiveness and cost-effectiveness of lung age (LA) or exhaled carbon monoxide (CO) feedback combined with very brief advice (VBA) to prompt smoking cessation compared with VBA alone, delivered by GPs in primary care in North Macedonia. All participants who decided to attempt to quit smoking were advised about accessing smoking cessation medications and were also offered behavioural support as part of the "ACT" component of VBA. Participants were aged ≥ 35 years, smoked ≥ 10 cigarettes per day, were recruited from 31 GP practices regardless of motivation to quit and were randomised (1:1:1) using a sequence generated before the start of recruitment. The primary outcome was biochemically validated 7-day point prevalence abstinence at 4 weeks (wks). Participants and GPs were not blinded to allocation after randomisation, however outcome assessors were blind to treatment allocation. RESULTS: There was no evidence of a difference in biochemically confirmed quitting between intervention and control at 4wks (VBA + LA RR 0.90 (97.5%CI: 0.35, 2.27); VBA + CO RR 1.04 (97.5%CI: 0.44, 2.44)), however the absolute number of quitters was small (VBA + LA 1.6%, VBA + CO 1.8%, VBA 1.8%). A similar lack of effect was observed at 12 and 26wks, apart from in the VBA + LA arm where the point estimate was significant but the confidence intervals were very wide. In both treatment arms, a larger proportion reported a reduction in cigarettes smoked per day at 4wks (VBA + LA 1.30 (1.10, 1.54); VBA + CO 1.23 (1.03, 1.49)) compared with VBA. The point estimates indicated a similar direction of effect at 12wks and 26wks, but differences were not statistically significant. Quantitative process measures indicated high fidelity to the intervention delivery protocols, but low uptake of behavioural and pharmacological support. VBA was the dominant intervention in the health economic analyses. CONCLUSION: Overall, there was no evidence that adding LA or CO to VBA increased quit rates. However, a small effect cannot be ruled out as the proportion quitting was low and therefore estimates were imprecise. There was some evidence that participants in the intervention arms were more likely to reduce the amount smoked, at least in the short term. More research is needed to find effective ways to support quitting in settings like North Macedonia where a strong smoking culture persists. TRIAL REGISTRATION: The trial was registered at http://www.isrctn.com (ISRCTN54228638) on the 07/09/2018.

European Respiratory Society/American Thoracic Society technical statement: standardisation of the measurement of lung volumes, 2023 update.

This document updates the 2005 European Respiratory Society (ERS) and American Thoracic Society (ATS) technical standard for the measurement of lung volumes. The 2005 document integrated the recommendations of an ATS/ERS task force with those from an earlier National Heart, Lung, and Blood Institute workshop that led to the publication of background papers between 1995 and 1999 and a consensus workshop report with more in-depth descriptions and discussion. Advancements in hardware and software, new research and emerging approaches have necessitated an update to the 2005 technical standard to guide laboratory directors, physiologists, operators, pulmonologists and manufacturers. Key updates include standardisation of linked spirometry, new equipment quality control and validation recommendations, generalisation of the multiple breath washout concept beyond nitrogen, a new acceptability and grading system with addition of example tracings, and a brief review of imaging and other new techniques to measure lung volumes. Future directions and key research questions are also noted.

ERS technical standards for using type III devices (limited channel studies) in the diagnosis of sleep disordered breathing in adults and children.

For more than three decades, type III devices have been used in the diagnosis of sleep disordered breathing in supervised as well as unsupervised settings. They have satisfactory positive and negative predictive values for detecting obstructive and central sleep apnoea in populations with moderately high pre-test probability of symptoms associated with these events. However, standardisation of commercially available type III devices has never been undertaken and the technical specifications can vary widely. None have been subjected to the same rigorous processes as most other diagnostic modalities in the medical field. Although type III devices do not include acquisition of electroencephalographic signals overnight, the minimum number of physical sensors required to allow for respiratory event scoring using standards outlined by the American Academy of Sleep Medicine remains debatable. This technical standard summarises data on type III studies published since 2007 from multiple perspectives in both adult and paediatric sleep practice. Most importantly, it aims to provide a framework for considering current type III device limitations in the diagnosis of sleep disordered breathing while raising research- and practice-related questions aimed at improving our use of these devices in the present and future.

A Race-neutral Approach to the Interpretation of Lung Function Measurements.

Rationale: The use of self-reported race and ethnicity to interpret lung function measurements has historically assumed that the observed differences in lung function between racial and ethnic groups were because of thoracic cavity size differences relative to standing height. Very few studies have considered the influence of environmental and social determinants on pulmonary function. Consequently, the use of race and ethnicity-specific reference equations may further marginalize disadvantaged populations. Objectives: To develop a race-neutral reference equation for spirometry interpretation. Methods: National Health and Nutrition Examination Survey (NHANES) III data (n = 6,984) were reanalyzed with sitting height and the Cormic index to investigate whether body proportions were better predictors of lung function than race and ethnicity. Furthermore, the original GLI (Global Lung Function Initiative) data (n = 74,185) were reanalyzed with inverse-probability weights to create race-neutral GLI global (2022) equations. Measurements and Main Results: The inclusion of sitting height slightly improved the statistical precision of reference equations compared with using standing height alone but did not explain observed differences in spirometry between the NHANES III race and ethnic groups. GLI global (2022) equations, which do not require the selection of race and ethnicity, had a similar fit to the GLI 2012 "other" equations and wider limits of normal. Conclusions: The use of a single global spirometry equation reflects the wide range of lung function observed within and between populations. Given the inherent limitations of any reference equation, the use of GLI global equations to interpret spirometry requires careful consideration of an individual's symptoms and medical history when used to make clinical, employment, and insurance decisions.

Feasibility of a pulmonary rehabilitation programme for patients with symptomatic chronic obstructive pulmonary disease in Georgia: a single-site, randomised controlled trial from the Breathe Well Group.

OBJECTIVES: To assess the feasibility of delivering a culturally tailored pulmonary rehabilitation (PR) programme and conducting a definitive randomised controlled trial (RCT). DESIGN: A two-arm, randomised feasibility trial with a mixed-methods process evaluation. SETTING: Secondary care setting in Georgia, Europe. PARTICIPANTS: People with symptomatic spirometry-confirmed chronic obstructive pulmonary disease recruited from primary and secondary care. INTERVENTIONS: Participants were randomised in a 1:1 ratio to a control group or intervention comprising 16 twice-weekly group PR sessions tailored to the Georgian setting. PRIMARY AND SECONDARY OUTCOME MEASURES: Feasibility of the intervention and RCT were assessed according to: study recruitment, consent and follow-up, intervention fidelity, adherence and acceptability, using questionnaires and measurements at baseline, programme end and 6 months, and through qualitative interviews. RESULTS: The study recruited 60 participants (as planned): 54 (90%) were male, 10 (17%) had a forced expiratory volume in 1 second of ≤50% predicted. The mean MRC Dyspnoea Score was 3.3 (SD 0.5), and mean St George's Respiratory Questionnaire (SGRQ) 50.9 (SD 17.6). The rehabilitation specialists delivered the PR with fidelity. Thirteen (43.0%) participants attended at least 75% of the 16 planned sessions. Participants and rehabilitation specialists in the qualitative interviews reported that the programme was acceptable, but dropout rates were high in participants who lived outside Tbilisi and had to travel large distances. Outcome data were collected on 63.3% participants at 8 weeks and 88.0% participants at 6 months. Mean change in SGRQ total was -24.9 (95% CI -40.3 to -9.6) at programme end and -4.4 (95% CI -12.3 to 3.4) at 6 months follow-up for the intervention group and -0.5 (95% CI -8.1 to 7.0) and -8.1 (95% CI -16.5 to 0.3) for the usual care group at programme end and 6 months, respectively. CONCLUSIONS: It was feasible to deliver the tailored PR intervention. Approaches to improve uptake and adherence warrant further research. TRIAL REGISTRATION NUMBER: ISRCTN16184185.

Community lung health service design for COPD patients in China by the Breathe Well group.

COPD is increasingly common in China but is poorly understood by patients, medications are not used as prescribed and there is no access to recommended non-pharmacological treatment. We explored COPD patients' and general practitioners' (GPs) knowledge of COPD, views on its management and the acceptability of a flexible lung health service (LHS) offering health education, exercise, self-management, smoking cessation and mental health support. Using a convergent mixed methods design, data were collected from patients and GPs using focus groups (FGs) in four Chinese cities, questionnaires were also used to collect data from patients. FGs were audio-recorded and transcribed. Quantitative data were analysed descriptively, thematic framework analysis was used for the qualitative data. Two-hundred fifty-one patients completed the questionnaire; 39 patients and 30 GPs participated in ten separate FGs. Three overarching themes were identified: patients' lack of knowledge/understanding of COPD, current management of COPD not meeting patients' needs and LHS design, which was well received by patients and GPs. Participants wanted COPD education, TaiChi, psychological support and WeChat for social support. 39% of survey responders did not know what to do when their breathing worsened and 24% did not know how to use their inhalers. 36% of survey respondents requested guided relaxation. Overall, participants did not fully understand the implications of COPD and current treatment was sub-optimal. There was support for developing a culturally appropriate intervention meeting Chinese patients' needs, health beliefs, and local healthcare delivery. Further research should explore the feasibility of such a service.

COVID-19-related changes in outpatient CPAP setup pathways for OSA are linked with decreased 30-day CPAP usage.

The COVID-19 pandemic changed continuous positive airway pressure (CPAP) setup pathways. We evaluated patients commenced on CPAP in 2019 (prepandemic) and 2020 (post-first UK wave). Face-to-face (F2F) setup numbers, with CPAP turned on, decreased from 613 patients (98.9%) in 2019, to 6 (1.1%) in 2020. In 2020, setups were F2F without CPAP turned on (403 (71.1%)), or remote (158 (27.9%)). Prepandemic median CPAP usage at first follow-up was 5.4 (2.7-6.9) hours/night and fell by 0.9 hours/night (95% CI 0.5 to 1.2, p<0.0001) in 2020. We found clinically relevant reductions in CPAP usage with pathway changes post-COVID-19.

The benefits of a home non-invasive ventilation retrieval service: Improved effectiveness and environmental sustainability in challenging times.

In the last 6 months, home non-invasive ventilation (NIV) services have faced several unanticipated challenges to their effectiveness and delivery as the result of a 'perfect storm' of the COVID-19 pandemic demands. We developed and delivered an innovative follow-up service, to support home NIV delivery, and improve cost-effectiveness and sustainability during COVID-19. Between Feb-2019 and Nov-2020, 92 post-acute patients were issued with home NIV; 25 (27%) out of the 92 patients had unused NIV machines successfully retrieved. The median (IQR) days of home NIV usage were 207 (98) for patients who had their machines returned. All the unused NIV machines retrieved were within the 5-year working life guaranteed by the manufacturer and were all redeployed after appropriate reconditioning and infection control measures. Without the home-visiting and recycling pilot, we would have relied on patients and families to return the unused machines. Given the expected disruption to NIV machine supply for at least the foreseeable 12-18 months, we feel it is important to get this important message out to other home NIV services urgently. Wider implementation of this novel approach could increase the availability of this vital resource and help meet the current demand on home NIV services.

Effect of obstructive sleep apnoea on retinal microvascular function: a randomised controlled trial.

PURPOSE: Retinal microvascular endothelial dysfunction is thought to be of importance in the development of ocular vascular diseases. Obstructive sleep apnoea (OSA) causes macrovascular endothelial dysfunction, but the effect of OSA on retinal microvascular endothelial function is not known. We aimed to determine the effect of OSA on retinal microvascular function. METHODS: We conducted a multi-centre, double-blind, randomised, parallel, controlled trial in patients with known moderate-to-severe OSA, established on continuous positive airway pressure (CPAP). Participants were randomised to 14 nights of either continued CPAP or sham CPAP to generate a return of OSA. Retinal vascular responses to flickering light were measured using dynamic vessel analysis both at baseline and after 14 nights of intervention. The primary outcome was the change from baseline to follow-up in the area under the curve of the arteriolar response to flickering light, sham CPAP versus continued CPAP. RESULTS: Nineteen patients were randomised to sham CPAP, and 18 patients were randomised to continued CPAP. There was no significant effect of CPAP withdrawal and return of OSA on retinal responses, with a change in the area under the curve of the arteriole response to flickering light of + 3.8 arbitrary units (95% CI - 10.6 to + 18.2, p = 0.59), sham CPAP versus continued CPAP. CONCLUSIONS: CPAP withdrawal and a return of OSA had no significant effect on retinal microvascular responses. This contrasts with the effect of CPAP withdrawal on macrovascular endothelial function and suggests that OSA has different effects on macrovascular and microvascular endothelial function. ISRCTN 78082983, 23/10/2014, Prospectively registered.

Medium-Term Outcomes in Severely to Critically Ill Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

BACKGROUND: The medium- and long-term effects of severe acute respiratory syndrome coronavirus 2 infection on survivors are unknown. In the current study, we assessed the medium-term effects of coronavirus disease 2019 (COVID-19) on survivors of severe disease. METHODS: This is a retrospective, case series of 200 patients hospitalized across 3 large Birmingham hospitals with severe-to-critical COVID-19 infection 4-7 months from disease onset. Patients underwent comprehensive clinical, laboratory, imaging, lung function tests (LFTs), and quality of life and cognitive assessments. RESULTS: At 4-7 months after disease onset, 63.2% of patients reported persistent breathlessness; 53.5%, significant fatigue; 37.5%, reduced mobility; and 36.8% pain. Serum markers of inflammation and organ injuries that persisted at hospital discharge had normalized on follow-up, indicating no sustained immune response causing chronic maladaptive inflammation. Chest radiographs showed complete resolution in 82.8%, and significant improvement or no change in 17.2%. LFTs revealed gas transfer abnormalities in 80.0% and abnormal spirometric values in 37.6% of patients. Compared with patients who did not experience breathlessness, those who did had significantly higher incidences of comorbid conditions and residual chest radiographic and LFT abnormalities (P < .01 to all). For all parameters assessed and persisting symptoms there were no significant differences between patients in hospital wards and those in intensive treatment units. All patients reported a significantly reduced quality of life in all domains of the EQ-5D-5L quality-of-life measures. CONCLUSIONS: A significant proportion of severely ill patients with COVID-19 still experience symptoms of breathlessness, fatigue, pain, reduced mobility, depression and reduced quality of life 4-7 months after disease onset. Symptomatic patients tend to have more residual chest radiographic and LFT abnormalities.

ERS/ATS technical standard on interpretive strategies for routine lung function tests.

BACKGROUND: Appropriate interpretation of pulmonary function tests (PFTs) involves the classification of observed values as within/outside the normal range based on a reference population of healthy individuals, integrating knowledge of physiological determinants of test results into functional classifications and integrating patterns with other clinical data to estimate prognosis. In 2005, the American Thoracic Society (ATS) and European Respiratory Society (ERS) jointly adopted technical standards for the interpretation of PFTs. We aimed to update the 2005 recommendations and incorporate evidence from recent literature to establish new standards for PFT interpretation. METHODS: This technical standards document was developed by an international joint Task Force, appointed by the ERS/ATS with multidisciplinary expertise in conducting and interpreting PFTs and developing international standards. A comprehensive literature review was conducted and published evidence was reviewed. RESULTS: Recommendations for the choice of reference equations and limits of normal of the healthy population to identify individuals with unusually low or high results are discussed. Interpretation strategies for bronchodilator responsiveness testing, limits of natural changes over time and severity are also updated. Interpretation of measurements made by spirometry, lung volumes and gas transfer are described as they relate to underlying pathophysiology with updated classification protocols of common impairments. CONCLUSIONS: Interpretation of PFTs must be complemented with clinical expertise and consideration of the inherent biological variability of the test and the uncertainty of the test result to ensure appropriate interpretation of an individual's lung function measurements.

Measurement of breathing in patients with post-COVID-19 using structured light plethysmography (SLP).

INTRODUCTION: COVID-19 pandemic has had a huge impact on global health to date, with 5.6 million cases in the UK since its emergence. The respiratory symptoms largely mimic those of pneumonia' with symptoms ranging from mild to severe. The effects on respiratory physiology are not yet fully understood, but evidence is emerging that there is much dysfunctional breathing reported but little information on tidal ventilation from the acute phase of the infection. Structured light plethysmography (SLP) is a contactless technique of respiratory function testing that measures tidal breathing parameters by assessing thoracoabdominal displacement. METHODS: In a postdischarge clinic, SLP was performed routinely on 110 hospitalised patients recovering from COVID-19 who had been screened for respiratory symptoms to confirm any respiratory changes occurring after the disease. Patients were categorised based on their hospital treatment in (1) the intensive therapy unit (ITU) (requiring intubation) (n=65) or (2) respiratory wards only (n=45). Data from these two patient cohorts were compared with preacquired data from healthy controls (n=30). RESULTS: We have found a significantly increased respiratory rate (p=0.006) in ITU patients compared with the healthy cohort and also a significant decrease in the inspiratory time (p=0.01), expiratory time (p=0.005) and the total breathing cycle (p=0.008). There were no significant differences between ITU and ward patients and no significant differences in healthy compared with ward patients. We examined the variability of breathing ('entropy') both in terms of the breath-to-breath interval and the volume-to-volume change. The breath-to-breath interval alone was significantly lower in ITU patients compared with healthy cohorts (p=0.02). CONCLUSION: Our findings suggest that abnormalities in tidal breathing can be detected in COVID-19 recovery patients, and SLP may be a promising tool in assessing the aftermath of diseases such as COVID-19, particularly if more intensive management strategies such as mechanical ventilation are required.

Lung function and breathing patterns in hospitalised COVID-19 survivors: a review of post-COVID-19 Clinics.

INTRODUCTION: There is relatively little published on the effects of COVID-19 on respiratory physiology, particularly breathing patterns. We sought to determine if there were lasting detrimental effect following hospital discharge and if these related to the severity of COVID-19. METHODS: We reviewed lung function and breathing patterns in COVID-19 survivors > 3 months after discharge, comparing patients who had been admitted to the intensive therapy unit (ITU) (n = 47) to those who just received ward treatments (n = 45). Lung function included spirometry and gas transfer and breathing patterns were measured with structured light plethysmography. Continuous data were compared with an independent t-test or Mann Whitney-U test (depending on distribution) and nominal data were compared using a Fisher's exact test (for 2 categories in 2 groups) or a chi-squared test (for > 2 categories in 2 groups). A p-value of < 0.05 was taken to be statistically significant. RESULTS: We found evidence of pulmonary restriction (reduced vital capacity and/or alveolar volume) in 65.4% of all patients. 36.1% of all patients has a reduced transfer factor (TLCO) but the majority of these (78.1%) had a preserved/increased transfer coefficient (KCO), suggesting an extrapulmonary cause. There were no major differences between ITU and ward lung function, although KCO alone was higher in the ITU patients (p = 0.03). This could be explained partly by obesity, respiratory muscle fatigue, localised microvascular changes, or haemosiderosis from lung damage. Abnormal breathing patterns were observed in 18.8% of subjects, although no consistent pattern of breathing pattern abnormalities was evident. CONCLUSIONS: An "extrapulmonary restrictive" like pattern appears to be a common phenomenon in previously admitted COVID-19 survivors. Whilst the cause of this is not clear, the effects seem to be similar on patients whether or not they received mechanical ventilation or had ward based respiratory support/supplemental oxygen.

Accuracy and cost-effectiveness of different screening strategies for identifying undiagnosed COPD among primary care patients (≥40 years) in China: a cross-sectional screening test accuracy study: findings from the Breathe Well group.

OBJECTIVES: To examine the accuracy and cost-effectiveness of various chronic obstructive pulmonary disease (COPD) screening tests and combinations within a Chinese primary care population. DESIGN: Screening test accuracy study. SETTING: Urban and rural community health centres in four municipalities of China: Beijing (north), Chengdu (southwest), Guangzhou (south) and Shenyang (northeast). PARTICIPANTS: Community residents aged 40 years and above who attended community health centres for any reason were invited to participate. 2445 participants (mean age 59.8 (SD 9.6) years, 39.1% (n=956) male) completed the study (February-December 2019), 68.9% (n=1684) were never-smokers and 3.6% (n=88) had an existing COPD diagnosis. 13.7% (n=333) of participants had spirometry-confirmed airflow obstruction. INTERVENTIONS: Participants completed six index tests (screening questionnaires (COPD Diagnostic Questionnaire, COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk (CAPTURE), Chinese Symptom-Based Questionnaire (C-SBQ), COPD-SQ), microspirometry (COPD-6), peak flow (model of peak flow meters used in the study (USPE)) and the reference test (ndd Easy On-PC). PRIMARY AND SECONDARY OUTCOMES: Cases were defined as those with forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) below the lower limit of normal (LLN-GLI) on the reference test. Performance of individual screening tests and their combinations was evaluated, with cost-effectiveness analyses providing cost per additional true case detected. RESULTS: Airflow measurement devices (sensitivities 64.9% (95% CI 59.5% to 70.0%) and 67.3% (95% CI 61.9% to 72.3%), specificities 89.7% (95% CI 88.4% to 91.0%) and 82.6% (95% CI 80.9% to 84.2%) for microspirometry and peak flow, respectively) generally performed better than questionnaires, the most accurate of which was C-SBQ (sensitivity 63.1% (95% CI 57.6% to 68.3%) specificity 74.2% (95% CI 72.3% to 76.1%)). The combination of C-SBQ and microspirometry used in parallel maximised sensitivity (81.4%) (95% CI 76.8% to 85.4%) and had specificity of 68.0% (95% CI 66.0% to 70.0%), with an incremental cost-effectiveness ratio of £64.20 (CNY385) per additional case detected compared with peak flow. CONCLUSIONS: Simple screening tests to identify undiagnosed COPD within the primary care setting in China is possible, and a combination of C-SBQ and microspirometry is the most sensitive and cost-effective. Further work is required to explore optimal cut-points and effectiveness of programme implementation. TRIAL REGISTRATION NUMBER: ISRCTN13357135.

Community-based intervention for prevention and management of chronic obstructive pulmonary disease in Nepal (COBIN-P trial): study protocol for a cluster-randomized controlled trial.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide and the commonest of non-communicable diseases (NCDs) in Nepal. Risk factors like indoor and outdoor air pollution, a high prevalence of smoking, and the lack of awareness of COPD make it a serious public health concern. However, no attempt has been made in Nepal to estimate its burden and address the disease at the community level. METHOD: This study aims to evaluate the effect of a community-based health educational intervention administered by Female Community Health Volunteers (FCHVs) on the prevention and management of COPD. An open-label, two-group, community-based, cluster-randomized controlled trial will be implemented in the semi-urban area of Pokhara Metropolitan city (former Lekhnath Municipality) located in the Kaski district of Nepal. The estimated sample size of the intervention will be 1143. The unit of randomization is the ward (administrative unit) of the study area. The follow-up survey will be conducted immediately after 12 months of FCHVs-led interventions. The difference in the rate of decline of forced expiratory volume in 1 s (FEV1) and FEV1/FVC (forced vital capacity) ratio are the primary outcomes and the change in the proportion of modifiable risk factors of COPD, health-related quality of life scores, and change in knowledge of COPD will be secondary outcomes. DISCUSSION: This study will estimate the burden of COPD, the magnitude of risk factors and generate evidence to mobilize community health workers for COPD prevention and management at the community level in Nepal. TRIAL REGISTRATION: ClinicalTrials.gov NCT03797768 . Registered on January 9, 2019.