Daily Respiratory Research Analysis
Three studies stand out today for advancing respiratory care: long-term real-world evidence shows allergen immunotherapy reduces medications and severe asthma outcomes in children; a blinded diagnostic study validates AI-supported spirometry to accurately detect COPD in primary care; and a very large matched cohort suggests nirmatrelvir-ritonavir during acute COVID-19 lowers post-COVID condition risk in older adults.
Summary
Three studies stand out today for advancing respiratory care: long-term real-world evidence shows allergen immunotherapy reduces medications and severe asthma outcomes in children; a blinded diagnostic study validates AI-supported spirometry to accurately detect COPD in primary care; and a very large matched cohort suggests nirmatrelvir-ritonavir during acute COVID-19 lowers post-COVID condition risk in older adults.
Research Themes
- AI-enabled diagnosis in primary care respiratory disease
- Long-term effectiveness of allergen immunotherapy in pediatric respiratory allergy
- Antiviral therapy during acute COVID-19 and risk of post-COVID conditions
Selected Articles
1. Long-Term, Real-World Effectiveness of Allergen Immunotherapy in Children and Adolescents With Allergic Rhinitis and Asthma.
In a matched cohort of 11,036 children followed for 9 years, allergen immunotherapy was associated with sustained reductions in allergic rhinitis medications. Among children with asthma, AIT was linked to additional decreases in asthma medications, severe exacerbations, and new oral corticosteroid prescriptions, with stronger benefits in younger children.
Impact: This is one of the largest long-term real-world pediatric datasets showing disease-modifying benefits of AIT across allergic rhinitis and asthma outcomes, supporting early initiation strategies.
Clinical Implications: Supports offering AIT earlier in children with allergic rhinitis (with or without asthma) to reduce medication burden, severe exacerbations, and steroid exposure over many years; informs payers and clinicians on long-term value.
Key Findings
- AIT led to an additional 9% reduction in allergic rhinitis medication use beyond a 61% reduction in controls.
- In children with asthma, AIT was associated with further reductions in asthma medication use (-21% beyond -48% in controls) and severe exacerbations (-21% beyond -36%).
- New oral corticosteroid prescriptions were reduced by an additional 33% (beyond -41% in controls), with stronger effects in children aged 0–11 years.
Methodological Strengths
- Large, matched cohort (n=11,036) with 9-year follow-up using comprehensive prescription databases
- Protocol-specified objectives within the REACT framework enhancing reproducibility and transparency
Limitations
- Observational design susceptible to residual confounding despite matching
- Lack of detailed clinical phenotype data (e.g., lung function, allergen exposure) may limit mechanistic inference
Future Directions: Prospective pragmatic trials to validate age-stratified benefits and to quantify quality-of-life and healthcare utilization changes; biomarker-enabled studies to identify responders.
BACKGROUND: Respiratory allergies often begin in childhood and can progress over time, leading to increased disease burden. Allergen immunotherapy (AIT) is the only causal treatment for allergic respiratory diseases with disease-modifying potential. While randomised trials support its efficacy in controlling allergic rhinitis (AR) and asthma symptoms, long-term real-world data in children remain limited. METHODS: This paediatric study (n = 11,036) was conducted within the pre-defined framework of the REACT study, based on protocol-specified objectives. Children (< 18 years) with physician-diagnosed AR, with or without pre-existing asthma, were included. AIT-treated patients were matched 1:1 to non-AIT controls. Effectiveness was assessed over 9 years by comparing AR and asthma medication prescriptions, using a public database covering all reimbursable AIT products. Relative differences were calculated across the full observation period. RESULTS: AIT-treated children (mean age 11.4 years; 62.1% male) exhibited greater reductions in AR medication use than controls (additional 9% reduction beyond 61% in controls). In children with asthma, AIT was associated with additional reductions in asthma medication use (-21% beyond -48% in controls), severe exacerbations (-21% beyond -36%), and new oral corticosteroid prescriptions (-33% beyond -41%). Age stratification revealed more pronounced AR medication reductions in younger children (0-11 years) than in adolescents (12-17 years). CONCLUSION: This large-scale, real-world study supports the long-term effectiveness of AIT in children with AR, with or without asthma. The findings reflect improved disease control and suggest a disease-modifying effect of AIT. Early intervention, particularly in younger children, may help mitigate the progression of allergic disease.
2. Validation of artificial intelligence spirometry diagnostic support software in primary care: a blinded diagnostic accuracy study.
Using 1,113 primary care spirometry records and blinded expert consensus as a reference, AI software accurately identified COPD (AUC 0.914; sensitivity 84%, specificity 86.8%) and showed strong discrimination for interstitial lung disease, with modest performance for asthma.
Impact: Provides externally relevant evidence that AI can reliably interpret spirometry in primary care, addressing a major barrier to accurate COPD diagnosis and underdiagnosis.
Clinical Implications: Primary care may adopt AI-assisted spirometry to improve COPD case-finding and reduce misclassification; integration into workflows with clinician oversight could enhance diagnostic pathways.
Key Findings
- AI achieved AUC 0.914, sensitivity 84.0%, and specificity 86.8% for COPD detection versus blinded expert consensus.
- For interstitial lung disease and asthma, AUCs were 0.900 and 0.814, respectively, indicating strong and moderate discrimination.
- Analysis used raw spirometry data plus basic demographics in a supervised random-forest model.
Methodological Strengths
- Blinded comparison against expert pulmonologist consensus as reference standard
- Consecutive primary care population with real-world handheld spirometry
Limitations
- Single geographic area and retrospective data may limit generalizability
- Asthma and non-obstructive patterns showed lower performance, requiring complementary clinical data
Future Directions: Prospective multisite implementation studies to test clinical impact on COPD detection, treatment initiation, and outcomes; model refinement for asthma and mixed patterns.
OBJECTIVE AND DESIGN: The objective of the present study was to assess the discriminative accuracy of artificial intelligence (AI) software to identify COPD and other chronic respiratory diseases from primary care spirometry. This was a diagnostic study with blinded analysis. METHODS: Retrospective hand-held spirometry data from consecutive patients attending primary care clinics in Hillingdon (London, UK) between September 2015 and March 2019 were used. The index diagnosis was the "preferred" diagnosis determined by AI software (highest probability) using supervised random-forest machine learning to interpret raw spirometry data and basic demographics. The reference diagnosis was based on the consensus of expert pulmonologists with access to primary and secondary care medical notes and results of relevant investigations. Cross-tabulation of the index test results by the results of the reference standard for COPD and other respiratory disease categories provided the main outcome measures. RESULTS: In this primary care spirometry dataset from 1113 patients, 543 (48.8%) had a reference diagnosis of COPD. AI preferred diagnosis detected 456, achieving a sensitivity of 84.0% (95% CI 80.6-87.0%), specificity of 86.8% (83.8-89.5%), accuracy of 85.4% (83.2-87.5%) with area under curve (AUC) of 0.914 (0.896-0.930). AI preferred diagnosis identified 187 out of 249 patients with reference diagnosis of interstitial lung disease and 59 out of 107 patients with asthma, with AUCs of 0.900 (0.880-0.916) and 0.814 (0.790-0.836), respectively. CONCLUSION: AI software achieved high sensitivity and specificity in identifying COPD using spirometry and basic demographic data and may support accurate diagnosis of COPD in primary care. AI software performed less well for other chronic respiratory disease categories.
3. Risk of Post-COVID-19 Conditions Among Adolescents and Adults Who Received Nirmatrelvir-Ritonavir for Acute COVID-19: A Retrospective Cohort Study.
In a matched cohort of 291,433 treated and 582,866 untreated individuals, nirmatrelvir-ritonavir during acute COVID-19 was associated with reduced post-COVID condition risk among adults aged 50–64 (aHR 0.93) and ≥65 (aHR 0.88), with minimal to no effect in younger age groups.
Impact: This very large real-world analysis provides age-stratified evidence that antiviral treatment may lower long COVID risk in older adults, informing outpatient management strategies.
Clinical Implications: Consider early outpatient nirmatrelvir-ritonavir for eligible older adults to potentially reduce both severe disease and post-COVID conditions; shared decision-making is important for younger patients given minimal observed benefit.
Key Findings
- Nirmatrelvir-ritonavir was associated with lower PCC risk in adults aged 50–64 (aHR 0.93) and ≥65 years (aHR 0.88).
- Minimal effect in high-risk adults aged 18–49 (aHR 0.98) and no effect in high-risk adolescents 12–17 (aHR 1.06).
- Rigorous 1:2 matching on age, sex, month, and region using closed claims data across outpatient, telehealth, and ED settings.
Methodological Strengths
- Very large matched cohort with age-stratified analyses and predefined PCC definition
- Use of closed claims across care settings increases capture of outcomes
Limitations
- Observational design with potential residual confounding and misclassification of PCC from claims
- Treatment selection biases and timing relative to symptom onset may influence estimates
Future Directions: Prospective studies linking EHR and patient-reported outcomes to refine PCC phenotypes; randomized or quasi-experimental designs to assess causal impact of antivirals on long COVID.
BACKGROUND: Post-COVID-19 Conditions (PCC) potentially affect millions of people, but it is unclear whether treating acute COVID-19 with nirmatrelvir-ritonavir may reduce the risk of PCC. METHODS: This is a retrospective cohort study using real-world, closed claims data to assess the relationship between nirmatrelvir-ritonavir and PCC by age group (12-17, 18-49, 50-64, ≥65 years). Eligible patients had a COVID-19 index date (positive laboratory test, ICD-10 diagnosis code, or nirmatrelvir-ritonavir prescription) from 1 April to 31 August 2022, in the outpatient, telehealth, or emergency department setting, and had a higher risk of severe COVID-19 based on age (≥50 years) or underlying risk factors. Treated patients (ie, received a nirmatrelvir-ritonavir prescription within ±5 days of index date) were matched 1:2 on age, sex, month of index date, and HHS region with untreated patients. PCC was defined by the presence of ≥1 of 45 new-onset symptoms or conditions recorded ≥60 days after index date. RESULTS: Of the treated patients, 291 433 were matched to 582 866 untreated patients. Treatment with nirmatrelvir-ritonavir reduced PCC risk in adults 50-64 years (adjusted hazard ratio [aHR] 0.93, 95% confidence interval [CI] 0.92-0.95) and ≥65 years (aHR 0.88, 95% CI 0.87-0.90). Treatment had minimal effect among high-risk adults 18-49 years (aHR 0.98, 95% CI 0.97-0.99) and no effect among high-risk adolescents 12-17 years (aHR 1.06, 95% CI 0.66-1.13). CONCLUSIONS: Results using real-world data suggest a protective relationship between nirmatrelvir-ritonavir during acute illness and PCC risk among older adults, but not among adolescents. Consideration may be given to outpatient treatment of mild to moderate COVID-19 with nirmatrelvir-ritonavir to reduce the risk of severe disease and PCC.