Daily Respiratory Research Analysis
Three studies stand out today: a multi-cohort analysis shows race-neutral GLI equations improve asthma detection in Black children; a randomized trial finds CPAP helps prevent nocturnal blood pressure rises in normotensive patients with severe OSA; and a nationwide cohort suggests COVID-19 vaccination reduces acute COPD exacerbations. Together they influence diagnostic equity, cardiovascular prevention in sleep medicine, and respiratory vaccination strategy.
Summary
Three studies stand out today: a multi-cohort analysis shows race-neutral GLI equations improve asthma detection in Black children; a randomized trial finds CPAP helps prevent nocturnal blood pressure rises in normotensive patients with severe OSA; and a nationwide cohort suggests COVID-19 vaccination reduces acute COPD exacerbations. Together they influence diagnostic equity, cardiovascular prevention in sleep medicine, and respiratory vaccination strategy.
Research Themes
- Equity and accuracy in pulmonary function interpretation
- Cardiovascular prevention in obstructive sleep apnea
- Vaccination impact on chronic respiratory disease outcomes
Selected Articles
1. Race-Specific and Race-Neutral Equations for Lung Function and Asthma Diagnosis in Black Children.
Across three pediatric cohorts (n=1533), applying race-neutral GLI equations lowered percent-predicted FEV1 in Black children by ~12–13 percentage points versus race-specific equations, revealing previously missed airflow limitation. Consequently, many Black children became eligible for bronchodilator reversibility testing, improving objective asthma detection.
Impact: The work directly informs a global shift to race-neutral spirometry and quantifies its benefits for equitable asthma diagnosis in children, addressing a major health disparity.
Clinical Implications: Adopting race-neutral GLI equations in pediatric spirometry will increase identification of airflow limitation and eligibility for reversibility testing among Black children, leading to earlier, more equitable asthma diagnosis and management.
Key Findings
- Race-neutral GLI equations reduced percent-predicted FEV1 by 11.9–13.5 pp in Black children across three cohorts.
- Race-specific equations missed reduced FEV1 in 55% (CCAAPS) and 41% (MPAACH) of symptomatic/asthmatic Black children.
- Switching to race-neutral equations increased eligibility for bronchodilator reversibility testing by 38–44% in Black children.
Methodological Strengths
- Multi-cohort analysis with harmonized outcomes across diverse pediatric populations
- Direct comparison of diagnostic eligibility under race-specific vs race-neutral equations
Limitations
- Observational design; not a randomized diagnostic intervention
- Generalizability beyond included cohorts and age ranges may be limited
Future Directions: Prospective implementation studies assessing clinical outcomes and healthcare utilization after adopting race-neutral equations in pediatric and adult practices; guideline integration and EHR decision support.
IMPORTANCE: Use of the race-neutral Global Lung Initiative (GLI) equation has been shown to generate decreased lung function measures in Black children and adults. The effect on asthma detection and diagnosis in children is unknown. OBJECTIVE: To compare the use of race-specific vs race-neutral equations on subsequent asthma diagnosis in children. DESIGN, SETTING, AND PARTICIPANTS: The Childhood Asthma Management Program (CAMP, 1991-2012), the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS, 2001-2010), and the Mechanisms of Progression from Atopic Dermatitis to Asthma (MPAACH, 2016-2024) cohorts were included in this cohort study. Children in the CAMP cohort were aged 5 to 12 years with mild to moderate asthma. The CCAAPS and MPAACH cohorts included infants from atopic parents and children aged 0 to 2 years with atopic dermatitis, respectively. Data were analyzed from November 2023 to May 2024. EXPOSURES: Race-specific vs race-neutral GLI equations to define lung function. MAIN OUTCOMES AND MEASURES: Percent predicted values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), asthma or asthma symptoms, and eligibility for reversibility testing were determined. RESULTS: Among 1533 children, there were 849 CAMP (median [IQR] age, 8.7 [7.1-10.6] years; 138 [16%] Black, 711 [84%] White, and 498 [59%] male participants), 578 CCAAPS (median [IQR] age, 6.9 [6.7-7.0]; 115 [20%] Black, 463 [80%] White, and 315 [55%] male participants) and 106 MPAACH (median [IQR] age, 7.4 [7.1-7.8] years; 62 [58%] Black, 44 [42%] White, and 62 [58%] male participants). The median (IQR) percent predicted FEV1 in Black children decreased by 11.9 percentage points (pp) (10.4-13.1 pp) in CAMP, 13.5% pp (11.8-14.6 pp) in CCAAPS, and 13.2 pp (11.6-14.6 pp) in MPAACH compared with the race-specific equation. The race-specific equation failed to detect reduced percent predicted FEV1 in 12 of 22 Black children in CCAAPS with asthma symptoms (55%) and 5 of 15 Black children in MPAACH with asthma (41%). In CCAAPS, children with less than 90% predicted FEV1 based on race-specific equations were eligible for postreversibility testing to objectively diagnose asthma. When this asthma diagnostic algorithm was applied, 16 of 36 Black children in CCAAPS (44%) and 6 of 16 Black children in MPAACH (38%) who were not eligible for reversibility testing based on the race-specific equation became eligible with a less than 90% predicted FEV1 based on the race-neutral equation. CONCLUSIONS AND RELEVANCE: In this cohort study of 1533 children, the use of the race-neutral equation improved the detection of asthma in children. These results support the universal use of the race-neutral equation to improve asthma detection in children and help guide medical practice toward alleviating asthma-related health disparities.
2. Effect of continuous positive airway pressure on blood pressure in normotensive individuals with obstructive sleep apnoea: a randomised trial.
In a randomized controlled trial of normotensive severe OSA patients with dipping patterns, CPAP prevented increases in ambulatory BP observed under usual care, yielding a −3.4 mmHg difference in night-time diastolic BP (ITT) and −6.1 mmHg in night-time systolic BP (per-protocol). This suggests a protective role of CPAP against nocturnal BP rise in normotensive OSA.
Impact: Provides randomized evidence that CPAP may prevent nocturnal BP increases even in normotensive severe OSA, supporting cardiovascular risk mitigation earlier in the disease course.
Clinical Implications: Consider CPAP to prevent nocturnal BP rise in normotensive severe OSA with dipping profiles, potentially delaying hypertension onset; emphasize adherence to maximize benefit.
Key Findings
- Randomized trial in severe OSA, normotensive dippers: 60 completers; CPAP vs usual care.
- Intention-to-treat: night-time diastolic BP lower by −3.4 mmHg with CPAP vs usual care (p=0.015).
- Per-protocol: significant reductions across endpoints except daytime SBP; night-time SBP −6.05 mmHg.
Methodological Strengths
- Randomised, parallel-group, prospective design with ambulatory BP monitoring
- Both intention-to-treat and per-protocol analyses reported
Limitations
- Modest sample size limits power; ITT effects limited to night-time DBP
- Single-center or limited setting details; adherence variability may influence effects
Future Directions: Larger multicenter RCTs to confirm cardioprotective effects of CPAP in normotensive OSA, evaluate clinical cardiovascular outcomes, and define adherence thresholds for benefit.
BACKGROUND: The effects of continuous positive airway pressure (CPAP) on blood pressure (BP) in normotensive subjects, particularly among those with a dipping BP pattern, remain uncertain, raising questions about its indication for this group of patients. We assessed the impact of CPAP on BP in normotensive subjects with a dipping BP pattern and severe obstructive sleep apnoea (OSA). METHODS: This was a randomised, parallel, prospective, controlled trial. Inclusion criteria were: age ≥18 years, apnoea-hypopnoea index ≥30 events·h RESULTS: The 60 patients who completed the follow-up had a mean±sd age of 52.2±10.8 years and 40 (66.7%) were male. The intention-to-treat analysis showed no significant changes with CPAP, whereas the usual care group experienced increases in ABPM parameters. This resulted in a mean difference of -3.4 mmHg (95% CI -6.124- -0.676; p=0.015) in night-time diastolic BP between the groups. The per-protocol analysis indicated significant differences between the CPAP and usual care groups for all primary end-points, except for daytime systolic BP. For night-time systolic BP, the mean difference was -6.052 mmHg (95% CI -10.895- -1.208; p=0.016). CONCLUSION: These findings suggest a protective effect of CPAP, highlighting the importance of CPAP prescription for this population to control potential increases in BP and possibly prevent the onset of hypertension.
3. Effects of Vaccination on Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Nationwide Population-Based Cohort Study.
In a nationwide cohort with propensity score matching (n=3,602 matched), COVID-19 vaccination was associated with a 45% lower hazard of AECOPD (HR 0.55). Post hoc analyses showed COVID-19 infection elevated exacerbation risk mainly among unvaccinated COPD patients, suggesting vaccination attenuates infection-related exacerbation risk.
Impact: Real-world evidence links COVID-19 vaccination to fewer COPD exacerbations, supporting vaccination as a disease-modifying strategy in chronic respiratory care.
Clinical Implications: Prioritize COVID-19 vaccination in COPD management to reduce exacerbations and potentially blunt infection-triggered events; integrate vaccination status in exacerbation risk stratification.
Key Findings
- Propensity-matched cohort (n=3,602) showed lower AECOPD rates in vaccinated vs unvaccinated (HR 0.55; 95% CI 0.41–0.72).
- Exacerbation rate: 1,683 vs 3,410 per 10,000 person-years (vaccinated vs unvaccinated).
- COVID-19 infection increased AECOPD risk among unvaccinated (adjHR 2.06), but not significantly among vaccinated (adjHR 1.35).
Methodological Strengths
- Large nationwide database with propensity score matching
- Time-to-event modeling (Cox regression) with subgroup post hoc analyses
Limitations
- Observational design with potential residual confounding
- Details on COPD severity, inhaled therapy, and vaccination types/doses not fully detailed in abstract
Future Directions: Prospective studies to confirm causality, evaluate mechanistic pathways (immune modulation, infection severity), and assess combined effects with influenza/RSV vaccination.
BACKGROUND: Coronavirus disease 2019 (COVID-19) vaccination may offer benefits for patients with chronic obstructive pulmonary disease (COPD). However, the evidence on whether the vaccination decreases the frequency of acute exacerbation of COPD (AECOPD) is limited. METHODS: This study enrolled 41,606 individuals diagnosed with COPD using the Korean National Health Insurance System-severe acute respiratory syndrome coronavirus 2 (NHIS SARS-CoV-2) database between 2020 and 2021. A cohort of 3,602 individuals was analyzed through 1:1 propensity score matching of vaccinated and unvaccinated groups. The risk of AECOPD was evaluated using a Cox proportional hazards regression analysis. A post hoc analysis examined the impact of COVID-19 on AECOPD in vaccinated and unvaccinated groups among infected and uninfected subgroups. RESULTS: Throughout the study, the exacerbation rate was lower in the vaccinated group (1,683/10,000 person-years) compared to the unvaccinated group (3,410/10,000 personyears). The Cox proportional hazards model showed a significantly decreased risk of AECOPD in vaccinated individuals relative to unvaccinated individuals (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.41 to 0.72). post hoc analysis revealed that COVID-19 was associated with a higher risk of AECOPD in unvaccinated individuals (adjusted HR, 2.06; 95% CI, 1.28 to 3.33), while in vaccinated individuals, the risk did not significantly differ between those infected and not infected with COVID-19 (adjusted HR, 1.35; 95% CI, 0.42 to 4.36). CONCLUSION: COVID-19 vaccination appears to decrease the risk of AECOPD among individuals with COPD.