BACKGROUND: The 2025 British Thoracic Society (BTS) Winter Meeting delivered 3 days of cutting-edge science, clinical innovation and networking in wintry Westminster. Over 2500 attendees from 36 countries gathered to sha...BACKGROUND: The 2025 British Thoracic Society (BTS) Winter Meeting delivered 3 days of cutting-edge science, clinical innovation and networking in wintry Westminster. Over 2500 attendees from 36 countries gathered to share advances shaping the future of respiratory medicine. CONTENT: The programme opened with a session focused on emerging clinical trial data, showcasing pragmatic and mechanistic studies designed to address real-world challenges in respiratory care, setting the tone for a meeting focused on impact and innovation.Translational research featured strongly throughout the meeting, with organoids, precision-cut lung slices and air-liquid interface cultures providing new perspectives on disease mechanisms and therapeutic targets. Early career investigators presented discoveries in eosinophilic chronic obstructive pulmonary disease biology, microbiome-driven viral susceptibility and resistance risks in novel bronchiectasis therapies, while midcareer leaders advanced understanding of familial interstitial lung disease and virus-host interactions.Plenary sessions tackled pressing challenges, from air pollution and breathlessness diagnostics to genetic drivers of pulmonary hypertension, complemented by guest lectures on immune regulation, vaccine-preventable illness and drug discovery. Additionally, the meeting highlighted workforce transformation, emphasising the role of nurses, allied health professionals and pharmacists in delivering integrated, digitally enabled care. CONCLUSION: Reminding us that progress rests on both scientific endeavour and enduring professional bonds, the 2025 BTS Winter Meeting reaffirmed that respiratory research is for everyone-an essential driver of advancement across disciplines. Multidisciplinary working and inclusive engagement will be key to shaping future care and ensuring that innovation translates into better outcomes for patients worldwide.
BACKGROUND: Obstructive sleep apnoea (OSA) and narcolepsy are estimated to affect approximately 4.8% and 0.047% of the UK population, respectively. We do not know how many people have been diagnosed or how this varies ov...BACKGROUND: Obstructive sleep apnoea (OSA) and narcolepsy are estimated to affect approximately 4.8% and 0.047% of the UK population, respectively. We do not know how many people have been diagnosed or how this varies over time and by demographic factors. METHODS: We, therefore, conducted a historical population-based descriptive study estimating prevalence and incidence of diagnosed OSA and narcolepsy in England from 2000 to 2019 stratified by demographic factors, and compared estimates to Scotland, Wales and Northern Ireland. Data were from Clinical Practice Research Datalink (CPRD) primary care records linked to Hospital Episode Statistics (HES) admissions. The study population included people with ≥90 days follow-up between 1 January 2000 and 31 December 2019, no prior record of primary or central sleep apnoea, and aged ≥18 years (OSA only). Diagnoses were defined using the first coded record for each condition in CPRD or HES data. Annual prevalence was estimated at mid-year and directly age/sex-standardised to the national population. Incidence was estimated by dividing new diagnoses by total person-time at risk. RESULTS: In England, 2019 adult standardised diagnosed OSA prevalence was 1.40% (95% CI 1.40% to 1.41%) representing approximately 622 528 people; standardised narcolepsy prevalence was 0.020% (95% CI 0.019% to 0.021%) representing approximately 11 307 people. Despite increases over time, diagnosed incidence and prevalence remained substantially lower than published estimates of symptomatic frequency. Rates varied by age, sex, ethnicity and UK nation for both conditions, and urban-rural living, area-based deprivation and practice size for OSA. CONCLUSION: Our results call for high-quality research to drive initiatives that increase diagnosis rates and address variation.
OBJECTIVE: Despite extensive research on the detrimental effects of air pollution on respiratory diseases like asthma and chronic obstructive pulmonary disease, the impact on people with cystic fibrosis (CF) remains unde...OBJECTIVE: Despite extensive research on the detrimental effects of air pollution on respiratory diseases like asthma and chronic obstructive pulmonary disease, the impact on people with cystic fibrosis (CF) remains understudied. Our study aimed to quantify the association between air pollution exposure and lung function decline in people with CF in London, UK. METHODS: Using 10 years (2008-2017) of UK Cystic Fibrosis Registry data, we conducted a longitudinal cohort study to evaluate the association between air pollution and the rate of decline in percent predicted forced expiratory volume in 1 second (ppFEV) among people with CF. Residential postcode exposure was based on high-resolution models of particulate matter with a diameter of less than 2.5 μm (PM) and nitrogen dioxide (NO) from the London Air Pollution Toolkit. We estimated the temporal decline in ppFEV in high, medium and low exposure subgroups based on air pollutant concentration tertiles using linear mixed models with random intercepts. RESULTS: We used 3333 ppFEV measurements of 393 people with CF (122 children, 271 adults). Over 40% of these people with CF lived in postcodes falling into the most deprived national quintile. For PM, the adjusted mean ppFEV declined by 13.3% (95% CI -24.1% to -4.0%) over the study period in the high-exposure tertile compared with 8.5% (95% CI -11.7% to -6.4%) in the low-exposure tertile. Differences between the exposure groups were less consistent for NO. Children and people with CF with severe genotypes seemed particularly vulnerable. CONCLUSIONS: This study provides novel evidence of the detrimental impact of air pollution on lung function in people with CF. Our findings highlight the importance of addressing air pollution as a modifiable risk factor to improve long-term outcomes of people with CF, and the need for national studies of the impact of environmental factors on CF in the UK.
BACKGROUND: Spirometry is a measure of lung function used to make clinical decisions regarding the diagnosis and management of respiratory conditions. The goal of spirometry interpretation is to relate impairments in mec...BACKGROUND: Spirometry is a measure of lung function used to make clinical decisions regarding the diagnosis and management of respiratory conditions. The goal of spirometry interpretation is to relate impairments in mechanical lung function to pulmonary pathology. In many circumstances, interpretation of measured spirometric values relies on comparisons with a 'healthy' reference population. Such inferences assume that spirometric values in healthy populations follow a Gaussian distribution with impaired values concentrated in the lower tail. METHODS: We hypothesised that impairments in lung function mechanics generate spirometric values that follow a non-Gaussian distribution as predicted by extreme value analysis. We used a Gumbel distribution to model lung function impairment. We compared the Gaussian healthy distribution to the Gumbel impaired distribution to calculate the relative probability for impaired versus healthy values. The relative probability provides an objective measure of the likelihood that a particular spirometric value is within the healthy or impaired distribution. RESULTS: The potential usefulness of the relative probability was demonstrated in simulated cases, providing an objective delineation of the zone of uncertainty in the transition from normal to impaired lung function. CONCLUSIONS: Considering the spirometric measures from people with lung function impairment as a separate distribution from people with healthy lung function provides a more analytic assessment of impairment. Applying extreme value analysis, the relative probability of a spirometric measurement being impaired versus healthy and a more precise definition of the zone of uncertainty potentially provides more objective discrimination of the intersection between the healthy and impaired lung function ranges.
BACKGROUND: Our multicentre, double-blind, randomised, placebo-controlled Azithromycin therapy for prevention of chronic lung disease of prematurity trial assessed if early 10-day azithromycin treatment improved survival...BACKGROUND: Our multicentre, double-blind, randomised, placebo-controlled Azithromycin therapy for prevention of chronic lung disease of prematurity trial assessed if early 10-day azithromycin treatment improved survival without development of chronic lung disease of prematurity when compared with placebo in 796 preterm-born infants. Since antibiotic resistance remains a significant global health priority, we had preplanned macrolide-resistance assessment in recruited infants. We, therefore, identified baseline macrolide-resistant genes in respiratory samples and determined if this was altered by azithromycin treatment. Furthermore, we assessed if macrolide-resistant bacteria isolated from respiratory samples were also resistant to other common antibiotic classes. METHODS: Six common macrolide-resistant genes: (A), (B), (C), (F), (A/E) and (A) were identified by quantitative PCR (qPCR) from serial nasopharyngeal and endotracheal aspirates from recruited infants at baseline (pretreatment), day-5, day-10 and day-14 (post treatment). Azithromycin-resistant bacteria were assessed by culture in presence/absence of azithromycin and underlying resistance mechanisms were confirmed by qPCR. Resistance to other common antibiotics was also evaluated and molecular determinants were identified by whole genome sequencing. RESULTS: From 1108 (n=541 azithromycin, n=567 placebo) respiratory aspirates from 348 preterm infants, the overall prevalence of macrolide-resistant genes was similar in the placebo (63.7%) and azithromycin (63.9%) groups, with only (C) gene increased by azithromycin. Azithromycin-resistant bacteria were resistant to multiple clinically used antibiotics, being associated with several different underlying resistance mechanisms. Coagulase-negative staphylococci (CoNS) were the most recovered macrolide-resistant bacteria. CONCLUSIONS: Macrolide-resistant genes were noticeably prevalent in the placebo group, with minimal increase with azithromycin treatment, suggesting that, regardless of the additional use of azithromycin, judicious use of antibiotics is required in preterm-born infants.
BACKGROUND: Respiratory syncytial virus (RSV) causes substantial winter pressure on adult services. In the UK, RSV vaccination currently targets adults aged ≥75 years and care home residents; it remains uncertain whether...BACKGROUND: Respiratory syncytial virus (RSV) causes substantial winter pressure on adult services. In the UK, RSV vaccination currently targets adults aged ≥75 years and care home residents; it remains uncertain whether this age criterion alone meaningfully discriminates risk of poor outcome among adults hospitalised with RSV. METHODS: We pooled three UK hospital cohorts (one prospective, two retrospective) of adults admitted with acute respiratory infection (ARI) and PCR-confirmed RSV. The primary outcome was intensive care unit/high dependency unit (ICU/HDU) admission or all-cause mortality within 60 days. Prespecified predictors (age, sex and comorbidities) entered a least absolute shrinkage and selection operator (LASSO) penalised logistic regression; selected variables were refitted using standard logistic regression. Discrimination, calibration and decision-analytic performance were assessed using 1000-bootstrap internal validation and decision-curve analysis. RESULTS: Among 334 adults, 37 (11.1%) experienced the primary outcome. An age-only rule mirroring current UK vaccine age-eligibility (≥75 years) demonstrated only modest discrimination (optimism-adjusted area under the receiver operating characteristic curve (AUC) 0.58, 95% CI 0.48 to 0.65) and a compressed distribution of predicted risks. A four-predictor model-including age, COPD, active/previous cancer and dementia-achieved higher discrimination AUC (0.77 (0.69 to 0.85)), a wider spread of predicted risks and the greatest net benefit across clinically plausible escalation thresholds (5-20%). CONCLUSIONS: In adults hospitalised with RSV-associated ARI, simple age-based heuristics-including the UK ≥75-year threshold-showed only modest ability to discriminate risk of ICU/HDU admission/60-day mortality once hospitalised. Comorbidity-inclusive approaches may provide more informative hospital-level risk stratification and warrant evaluation in future RSV vaccine-effectiveness and outcome studies. Any application requires external validation, more systematic RSV testing and comparison with physiology-based scores in larger, vaccinated cohorts.
Mullin ML, Verghese P, Khaw CR
… +18 more, Creamer A, Bhamani A, Prendecki R, Dickson JL, Horst C, Tisi S, Hall H, Gyertson K, Arthur-Darkwa E, Farrelly L, McCabe J, Thakrar R, Nair A, Devaraj A, Navani N, Hackshaw A, SUMMIT consortium, Janes SM
INTRODUCTION: Lung cancer is the leading cause of cancer-related death worldwide. Low-dose CT (LDCT) screening improves outcomes by detecting early-stage cancers as pulmonary nodules. As most are benign, diagnosing these...INTRODUCTION: Lung cancer is the leading cause of cancer-related death worldwide. Low-dose CT (LDCT) screening improves outcomes by detecting early-stage cancers as pulmonary nodules. As most are benign, diagnosing these nodules is challenging and often requires surveillance imaging. The aim of this study is to assess the frequency of cancer progression in a lung cancer screening study as measured by tumour stage (T-stage). METHODS: SUMMIT is a prospective cohort study assessing implementation of lung cancer screening with LDCT in a high-risk population. Screen-detected lung cancers with clinical tumour stage cT1a-c at time of referral were included. Upstaging was defined as an increase in T-stage from referral to treatment. The date of death was obtained from the National Cancer Registration and Analysis Service. Cox proportional hazards analysis with adjustment for age, sex, Charlson Comorbidity Index and pack years was used to assess mortality between groups. RESULTS: 390 screen-detected cancers were stage cT1a-c at time of referral. Upstaging occurred more frequently in cT1a (n=48, 56%) compared with cT1b (n=83, 38%) or cT1c (n=34, 40%), p=0.01. The proportion of part-solid nodules was similar between groups (upstaged-N=47, 27%, vs not upstaged-N=45, 21%, p=0.19). 43% of tumours increased T-stage from referral to first treatment (n=165). In participants upstaged, time from referral to treatment was longer (upstaged: 84 days, 46-298 vs not upstaged: 72 days, 43-211, p=0.04). Adjusted overall survival analyses showed an association between upstaging and mortality (HR 1.68, 95% CI 1.13 to 2.51, p=0.01). CONCLUSION: Tumour upstaging occurred in nearly half of early-stage cases in a lung cancer screening population. Tumour upstaging was associated with longer time to treatment and poorer outcomes in this population. TRIAL REGISTRATION NUMBER: NCT03934866.
Taylor SL, Brooks CR, Pembrey L
… +21 more, Manning SK, Elms L, Mpairwe H, Figueiredo CA, Oviedo AY, Chico M, Burmanje J, Ali H, Nambuya I, Tumwesige P, Robertson S, Rutter CE, van Veldhoven K, Ring SM, Barreto ML, Cooper PJ, Cruz ÁA, Pearce N, Rogers GB, Douwes J, WASP Study Group
BACKGROUND: Asthma is an umbrella diagnosis encompassing distinct pathophysiological mechanisms. While a global problem, our understanding of the interplay between respiratory microbiology and airway inflammation is larg...BACKGROUND: Asthma is an umbrella diagnosis encompassing distinct pathophysiological mechanisms. While a global problem, our understanding of the interplay between respiratory microbiology and airway inflammation is largely from populations in high-income settings. As a result, treatment approaches align poorly with asthma characteristics in less studied populations. OBJECTIVE: To identify conserved and geographically distinct relationships between airway inflammation and microbiota characteristics in young people with and without asthma. METHODS: We conducted a cross-sectional study performing inflammatory phenotyping, microbiota analysis and enumeration of total bacteria, and on 488 induced sputum samples from participants from Brazil (asthma: 68; non-asthma: 8), Ecuador (asthma: 89; non-asthma: 30), Uganda (asthma: 61; non-asthma: 8), New Zealand (asthma: 129; non-asthma: 58) and the UK (asthma: 25; non-asthma: 20). Microbiota characteristics were compared by country, asthma status and inflammatory characteristics, adjusting for age and sex. RESULTS: Asthma inflammatory phenotypes and microbiology differed between countries, with Uganda characterised by higher neutrophils, microbial diversity and bacterial abundance. Comparison of airway inflammation with microbiota characteristics showed conserved relationships across centres, with airway neutrophil proportion explaining variance in microbiota Bray-Curtis dissimilarity (p<0.001) and being positively associated with bacterial abundance, including and load (all p<0.05). In contrast, eosinophil proportion was less strongly associated with microbiota dissimilarity (p=0.033) and only associated with abundance. Country-specific associations between airway inflammation and microbiology were evident. CONCLUSION: Both airway inflammation and microbiology varied geographically in young people with asthma. Associations between microbiota characteristics and neutrophilic phenotype were conserved.
BACKGROUND: Management of amyotrophic lateral sclerosis (ALS) is complicated by heterogeneous presentation and unpredictable disease course. This study described disease trajectories before and after initiation of non-in...BACKGROUND: Management of amyotrophic lateral sclerosis (ALS) is complicated by heterogeneous presentation and unpredictable disease course. This study described disease trajectories before and after initiation of non-invasive ventilation (NIV) therapy in individuals with ALS, examined the relationship between NIV initiation timing and survival and analysed health trajectory clusters. METHODS: Data were extracted from the French national health insurance reimbursement system database for individuals with ≥1 reimbursement for NIV from January 2015 to December 2019, and ≥1 ALS disease code. Health trajectory clusters were determined using time sequence analysis through K-clustering. RESULTS: We analysed data from 3443 individuals with ALS (58% male, median age 67 years). The median (IQR) time from ALS diagnosis to NIV initiation was 10.8 (4.5-22.2) months and death occurred 21.5 (12.8-33.9) months after diagnosis. Tracheostomy/gastrostomy was performed in 3.9%/33.4% of patients, respectively. Unsupervised machine learning clustering identified four distinct patient groups. NIV initiation was late in two Clusters (A and B); these individuals were younger, had fewer comorbidities and more physiotherapy sessions before/after NIV. Survival after NIV initiation was longer in Clusters B and C; these individuals had lower rates of depression/anxiety, more prescription of mechanical in/exsufflation therapy and fewer home and emergency hospitalisations. Cluster B was unique, showing late NIV initiation and long post-NIV survival. This cluster was more likely to have spinal onset, a higher rate of obstructive sleep apnoea and fewer comorbidities. CONCLUSIONS: There was marked heterogeneity between patients with ALS and their care trajectories. Our data do not support a universal benefit for early initiation of NIV therapy.
Mishra EK, Davies H, Abbas SH
… +28 more, Hardy C, Beith DT, Sethi D, Sapkal T, Elsheikh A, Yousuf A, Hedley EL, Daly E, Sundaralingam A, Addala D, Jones SA, Castle L, Patel N, Herre J, Collins H, Kastelik J, Ross CL, Corcoran J, Daneshvar C, Shiham F, Hufton A, Lynch GA, Dipper A, Barton E, Clive AO, Maskell NA, Clark AB, Rahman NM
INTRODUCTION: In patients with malignant pleural effusions (MPE), pleural fluid reaccumulates at variable rates following therapeutic aspiration. The aim of this study was to identify variables which predict time to next...INTRODUCTION: In patients with malignant pleural effusions (MPE), pleural fluid reaccumulates at variable rates following therapeutic aspiration. The aim of this study was to identify variables which predict time to next procedure and use them to develop a predictive score. METHODS: This prospective observational cohort study in 10 British hospitals recruited patients with known or suspected malignant effusions undergoing therapeutic aspiration. Follow-up lasted 3 months and assessed time to next clinically indicated pleural procedure. Regression analysis was performed to identify independent variables predicting time to next procedure, and a score derived. Initial validation was done in two external cohorts. MEASUREMENTS AND MAIN RESULTS: 241 patients were recruited. Within the derivation cohort (n=180), baseline respiratory rate (R), pleural effusion depth on ultrasound (E) and dyspnoea measured using a visual analogue scale (D) (combined to form the RED score) were independent predictors of time to next procedure. Predictive models provided areas under the receiver operator curve of 0.73 and 0.75. Initial validity testing in two cohorts (n=31, n=57) demonstrated reasonable predictive value. CONCLUSIONS: In patients with MPE, baseline respiratory rate, pleural effusion depth on ultrasound and dyspnoea predict time to next procedure. TRIAL REGISTRATION NUMBER: ISRCTN16567838.
BACKGROUND: Quadriceps maximal voluntary contraction (QMVC) reliably measures quadriceps muscle force and predicts mortality in chronic obstructive pulmonary disease (COPD). However, the minimal important difference (MID...BACKGROUND: Quadriceps maximal voluntary contraction (QMVC) reliably measures quadriceps muscle force and predicts mortality in chronic obstructive pulmonary disease (COPD). However, the minimal important difference (MID) of QMVC is not well-established. AIM: To estimate the MID of QMVC parameters in people with COPD following pulmonary rehabilitation (PR). METHODS: QMVC was measured before and after 8 weeks of outpatient PR in people with COPD. Absolute and % change in QMVC, and change in normalised QMVC were calculated using paired t-tests. Anchor and distribution-based methods (0.5×SD change, SEM, minimal detectable change at 95% confidence, effect size and 1.96 SEM) were used to estimate the MID. RESULTS: Of 903 participants, 383 were excluded due to PR non-completion or missing QMVC data with 520 included in the analysis (37% female; mean (SD) age 70.2 (8.4) years; forced expiratory volume in 1 s 51.4 (21.4)% predicted). QMVC parameters increased with PR; mean (95% CI) or mean (SD) change: QMVC 2.0 kg (1.5 kg to 2.5 kg), 10.6% (27.7%) and normalised QMVC 5.0% predicted (3.9% to 6.2%). Anchor-based MID estimates were precluded due to weak/no correlation with external anchors. Using distribution-based methods, the MID for QMVC change, QMVC % change and normalised QMVC change were estimated as mean (range) 3.55 kg (1.84 kg to 5.11 kg), 18.34% (9.60% to 26.60%) and 7.78% (3.78% to 12.48%) for all participants. However, MID estimates for absolute and % change in QMVC differed markedly between men and women. Normalised QMVC estimates demonstrated smaller sex-based discrepancies. CONCLUSION: We provide MID estimates for QMVC parameters. Sex-specific or normalised MID estimates for QMVC should be used to facilitate the interpretation of change.
BACKGROUND: Lung cancer screening is effective for people at higher risk of the disease, but there is no international consensus on eligibility criteria. Some programmes use risk factors; others use multivariable risk sc...BACKGROUND: Lung cancer screening is effective for people at higher risk of the disease, but there is no international consensus on eligibility criteria. Some programmes use risk factors; others use multivariable risk scores, which might target an older, more comorbid population and thus limit life years gained. In this study, we compare frailty, comorbidities and overall survival between different eligible populations. METHODS: Participants aged 55-74 years undergoing lung cancer risk assessment in the Yorkshire Lung Screening Trial were analysed, comparing those who met the US Preventive Services Task Force 2021 lung cancer screening criteria (USPSTF) criteria against established risk-based criteria currently used in screening protocols (Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial risk model (PLCO) ≥1.51%, used internationally, and the Liverpool Lung Project risk model (version 2) (LLP) ≥2.5%, used in the UK), examining the number of individuals with frailty and comorbidities selected by each approach. In addition, risk score thresholds were set to select equivalent numbers of people screened compared with USPSTF. Data recorded in primary care prior to randomisation were retrospectively extracted to allow calculation of the electronic Frailty Index (eFI) and an overall comorbidity count. Frailty, comorbidity counts and 3-year overall survival were compared between these various populations. RESULTS: Of 11 994 individuals aged 55-74 undergoing risk assessment, 3502 were eligible by USPSTF, 3139 by PLCO ≥1.51% and 3957 by LLP ≥2.5%. The proportion of individuals with moderate/severe frailty was lower for the USPSTF population (10.6%) compared with PLCO ≥1.51% (13.1%, adjusted p=0.0777) and LLP ≥2.5% (13.4%, adjusted p=0.0272). The USPSTF identified significantly fewer individuals with multiple comorbidities (30.8%) than the PLCO (36.1%, adjusted p=0.0033) and the LLP (37.3%, adjusted p=0.0001).When compared in equivalent populations, both PLCO with a threshold of 1.32%, and LLP with a threshold of 2.92%, had a higher proportion of people both with moderate/severe frailty (12.6%, adjusted p=0.221 and 14.0%, adjusted p=0.0067 respectively) and multiple comorbidities (35.1%, adjusted p=0.0211 and 38.5%, adjusted p<0.0001 respectively) than USPSTF.There were no apparent differences in 3-year overall survival between the eligible populations overlapping 95% CIs across risk groups. CONCLUSION: These data suggest that currently used risk models identify populations with a small increase in moderate/severe frailty and multimorbidity compared to the USPSTF criteria, but there is no evidence to suggest that this results in differences in 3-year overall survival.
INTRODUCTION: Positive airway pressure (PAP) therapy is the recognised treatment for sleep disordered breathing (SDB), delivered via a tight-fitting face mask (interface). Conventional interfaces do not consider facial g...INTRODUCTION: Positive airway pressure (PAP) therapy is the recognised treatment for sleep disordered breathing (SDB), delivered via a tight-fitting face mask (interface). Conventional interfaces do not consider facial geometries, often resulting in poor fit and ineffective therapy. Three-dimensional (3D) printing of customised interfaces may improve comfort and outcomes. OBJECTIVES: To evaluate the clinical impact of customised versus conventional oronasal interfaces in adults with obstrcutive sleep apnoea (OSA). The primary outcome was residual Apnoea Hypopnea Index (AHI) at 6 months; secondary outcomes included interface leak, therapy concordance and patient reported symptoms. METHODS: A randomised controlled trial with 160 adults naïve to PAP therapy and diagnosed with SDB (AHI ≥15 events/hour). Randomisation was minimised by age and ethnicity. Structured light facial scans (POP2, Revopoint, China) were used to produce 3D printed moulds (Fuse 30+, Formlabs, Massachusetts, USA) for silicone injected oronasal customised interface cushions.AHI was compared using quantile regression to account for the skewed distribution of the AHI data. Secondary outcomes were compared using logistic, quantile and linear regressions. RESULTS: 160 participants were recruited (intervention: 82, control: 78). Customised interfaces were associated with a 1.5 (events/hour) increase in AHI (p=0.059), higher interface leak (difference in medians 30.0 L/min, 95% CI 7.36 to 40.14, p<0.0001) and lower compliance (difference in compliance 0.78, 95% CI 0.05 to 1.54, p=0.04) at 6 months. CONCLUSIONS: This trial did not demonstrate customised oronasal interfaces were superior to conventional interfaces. Future research should focus on addressing design and manufacturing limitations before any potential advantages can be evaluated. TRIAL REGISTRATION NUMBER: ISRCTN74082423.