Daily Respiratory Research Analysis
Three studies reshape respiratory practice: (1) In obstructive sleep apnea, symptom-based subtypes and nocturnal hypoxic burden independently forecast different cardiovascular risks over >11 years, enabling refined risk stratification. (2) In primary care across five European countries, antibiotic courses for common respiratory infections are often longer than recommended, underscoring stewardship opportunities. (3) Real-world data from Spain show nirsevimab prophylaxis reduces respiratory suppo
Summary
Three studies reshape respiratory practice: (1) In obstructive sleep apnea, symptom-based subtypes and nocturnal hypoxic burden independently forecast different cardiovascular risks over >11 years, enabling refined risk stratification. (2) In primary care across five European countries, antibiotic courses for common respiratory infections are often longer than recommended, underscoring stewardship opportunities. (3) Real-world data from Spain show nirsevimab prophylaxis reduces respiratory support, PICU admission, and length of stay in infants hospitalized with RSV bronchiolitis.
Research Themes
- Sleep apnea phenotyping and hypoxic burden as cardiovascular risk predictors
- Antibiotic stewardship for respiratory tract infections in primary care
- RSV immunoprophylaxis effectiveness in hospitalized infants
Selected Articles
1. OSA symptom subtypes and hypoxic burden independently predict distinct cardiovascular outcomes.
In a cohort of 4396 adults followed for over 11 years, higher nocturnal hypoxic burden predicted cardiovascular mortality independent of symptom subtypes, while an excessively sleepy OSA subtype predicted incident MACE independent of hypoxic burden. Among moderate–severe OSA, hypoxic burden scaled with cardiovascular mortality and sleepy subtype with MACE.
Impact: It refines cardiovascular risk stratification in OSA by demonstrating independent and complementary prognostic value of symptom subtypes and hypoxic burden, informing precision treatment decisions.
Clinical Implications: Incorporate hypoxic burden and symptom phenotyping into routine OSA assessment to target therapies (e.g., CPAP prioritization for high HB; vigilance and cardiovascular prevention in ‘sleepy’ subtype), beyond AHI alone.
Key Findings
- Higher hypoxic burden independently associated with worse cardiovascular mortality (HR 1.63; p=0.009).
- Excessively sleepy OSA subtype independently associated with higher incident MACE risk (HR 1.62; p<0.001).
- In moderate–severe OSA (AHI ≥15), hypoxic burden predicted cardiovascular mortality, while the sleepy subtype predicted MACE.
Methodological Strengths
- Large, community-based cohort with >11 years of follow-up.
- Concurrent modeling of symptom subtypes and physiologic hypoxic burden with adjudicated outcomes.
Limitations
- Observational design limits causal inference.
- Generalizability may vary outside SHHS demographics and clinical OSA populations.
Future Directions: Prospective trials testing risk-guided therapy using hypoxic burden and symptom phenotypes to reduce MACE and cardiovascular mortality; integration into clinical decision tools.
STUDY OBJECTIVES: Studies on obstructive sleep apnoea (OSA) have identified clinically relevant symptom-based subtypes and novel OSA-specific nocturnal hypoxic measures. Both traits are individually associated with cardiovascular outcomes, but evidence about their independent or shared effects is unknown. This study investigated the simultaneous contributions of OSA symptom subtypes and hypoxic burden (HB) on incident cardiovascular outcomes. METHODS: Sleep Heart Health Study participants with high-quality oxygen saturation, apnoea-hypopnea index (AHI) and symptom data were included. Participants with OSA (AHI ≥5 events·h
2. Nirsevimab Prophylaxis for Reduction of Respiratory Syncytial Virus Complications in Hospitalised Infants: The Multi-Centre Study During the 2023-2024 Season in Andalusia, Spain (NIRSEGRAND).
In a nine-hospital cohort of 222 hospitalized infants with RSV bronchiolitis, nirsevimab prophylaxis was associated with large reductions in respiratory support use (nasal cannula and mechanical ventilation), PICU admission, and hospital length of stay after adjustment. A higher rate of co-infection was observed among immunized infants.
Impact: Provides timely real-world evidence on the hospital-level benefits of nirsevimab during widespread implementation, supporting policy and resource planning for RSV immunoprophylaxis.
Clinical Implications: Healthcare systems can expect reduced respiratory support needs and PICU utilization among infants receiving nirsevimab; clinicians should remain vigilant for co-infections and maintain diagnostic stewardship.
Key Findings
- Adjusted reductions with nirsevimab: nasal cannula use −64% (13–85%), mechanical ventilation −48% (1–73%), PICU admission −54% (14–75%).
- Hospital length of stay reduced by 30% (8–47%).
- Co-infection risk increased in immunized infants (aOR 3.42; 95% CI 1.52–7.68).
Methodological Strengths
- Multicenter cohort spanning all provinces with adjusted logistic and Cox models.
- Evaluation of multiple clinically meaningful severity endpoints.
Limitations
- Retrospective design and potential residual confounding.
- Possible selection bias in immunization uptake and hospital admission thresholds.
Future Directions: Prospective evaluations of nirsevimab impact on mortality and readmissions, assessment of co-infection mechanisms, and cost-effectiveness analyses to inform scaling strategies.
BACKGROUND: Nirsevimab was indicated in a population level for all infants < 6 months during the 2023-2024 season in Andalusia (southern Spain). Our aim was to analyse the effect of nirsevimab in the reduction in complications in infants hospitalised for RSV bronchiolitis. METHODS: A retrospective observational cohort study was conducted in nine relevant hospitals from all provinces of Andalusia, a region with over 9 million inhabitants. The study sample included 222 children, divided into two groups: infants administered with nirsevimab for passive immunisation (exposure) and infants not administered with nirsevimab. Clinical outcomes were analysed, including the use of respiratory support, the need for admission to paediatric intensive care unit (PICU), and duration of hospitalisation. Bivariate analyses were performed, and multivariable logistic regression models were designed to calculate adjusted odds ratios (ORa), and Cox regression models to calculate adjusted hazard ratios (HRa). RESULTS: Bivariate analysis showed an association between passive immunisation with nirsevimab and a lower frequency of numerous outcomes. After adjustment for relevant covariates, multivariable models showed that the exposure (nirsevimab) reduced nasal cannula use by 64% (13-85%), invasive or non-invasive mechanical ventilation by 48% (1-73%), PICU admission by 54% (14-75%), length of hospitalisation by 30% (8-47%), and length of nasal cannula by 31% (7-49%). A higher risk of co-infection was observed in those immunised (aOR = 3.42, 95%CI: 1.52-7.68). CONCLUSIONS: Passive immunisation with nirsevimab may decrease the severity of RSV bronchiolitis in infants requiring hospitalisation, thus contributing tertiary prevention that extends beyond the prevention of RSV infection.
3. Duration of antibiotic treatment for respiratory tract infections in primary care.
Across five European countries and 11,270 RTI encounters, one-third received antibiotics with a mean duration of 7.5 days, exceeding current guideline recommendations, including for conditions commonly viral in etiology. Findings highlight major opportunities to reduce unnecessary antibiotic exposure through duration optimization or avoidance.
Impact: Defines real-world prescribing durations at scale in primary care, directly informing stewardship interventions and guideline implementation for respiratory infections.
Clinical Implications: Implement duration defaults aligned with guidelines (e.g., 3–5 days where appropriate), strengthen diagnostic stewardship to avoid antibiotics in viral RTIs, and audit-prescribing with feedback to reduce unnecessary exposure.
Key Findings
- Among 11,270 RTI cases, 34% received antibiotics with a mean duration of 7.52 days.
- Durations were longest for pneumonia (8.01 d), COVID-19 infection (8.00 d), and pharyngotonsillitis (7.74 d).
- Even predominantly viral infections (common cold, influenza, laryngitis, acute bronchitis) had mean durations of 6.3–7.0 days, exceeding many recommendations.
Methodological Strengths
- Prospective, multicountry audit with standardized data capture across settings.
- Large sample enabling diagnosis-specific duration estimates.
Limitations
- Observational audit without linkage to outcomes or microbiology.
- Heterogeneity across countries and practices; potential documentation bias.
Future Directions: Interventional trials testing duration defaults, e-prescribing prompts, and audit-feedback on RTI antibiotic courses; integration with rapid diagnostics to reduce unnecessary prescribing.
OBJECTIVES: The primary driver of antimicrobial resistance is excessive antibiotic use, posing a global threat to public health. Reducing individual exposure to antibiotics is a key to addressing the problem. This study aimed to assess the duration of antibiotic courses administered to patients with acute respiratory tract infections (RTIs) in primary care. METHODS: Consecutive patients presenting with RTI symptoms were prospectively included from general practices and out-of-hours services in France, Greece, Lithuania, Poland and Spain for two winter periods (February to April 2022 and 2023). Data were collected using a paper-based Audit Project Odense template, with clinicians recording patient age, gender, RTI diagnosis, type of antibiotic prescribed and treatment duration. RESULTS: A total of 196 doctors (133 in general practice and 63 in out-of-hours services) registered 11 270 cases, with 34.0% (3835) receiving antibiotics. The mean antibiotic course duration was 7.52 days (SD 2.11), which was significantly longer for pneumonia, COVID-19 infection and pharyngotonsillitis (8.01, 8.00 and 7.74 days, respectively), and lowest for predominantly viral infections, such as the common cold and flu infection, laryngitis and acute bronchitis (6.32, 6.48 and 6.98 days, respectively; CONCLUSIONS: Antibiotic courses for common RTIs are often prolonged, which does not align with current recommendations for course duration. Antibiotics should be avoided in cases of predominantly viral infections and most mixed infections; however, if deemed necessary, the courses should be substantially reduced to minimize unnecessary exposure.