Impact of obstructive sleep apnea on outcomes of pulmonary embolism: A systematic review and meta‑analysis

Prognostic Value of Neutrophil/Lymphocyte Ratio for Pulmonary Embolism: A Meta-Analysis and External Validation

BACKGROUND

Prognostic value of neutrophil/lymphocyte ratio (NLR) for pulmonary embolism (PE) has been reported in several retrospective studies. The purpose of this investigation was to perform a pooled analysis and external validation of predictive value of NLR.

METHODS

PubMed, Embase, and Cochrane databases were searched from inception to November 5, 2022. A random effects model was used. Grade was used to evaluate the certainty of evidence. External validation was conducted in clinical cohorts before and after a propensity scoring matching (PSM). Covariates include basic clinical characteristics, such as age, gender, etc. The value of NLR in prediction model was also evaluated.

RESULTS

A total of 15 studies comprising 5,874 patients were included. Pooled risk ratio of NLR was 2.33 (95% confidence interval [CI]: 1.97-2.75), with an area under the curve of 0.78 (95% CI: 0.74-0.81), a sensitivity of 0.75 (95% CI: 0.71-0.79), a specificity of 0.67 (95% CI: 0.61-0.73), and a median cut-off value of 5.7. Grade of Recommendations Assessment Development and Evaluation (GRADE) certainty analysis showed the quality of the evidence was moderate. Before (n = 336) and after (n = 152) propensity scoring matching, risk ratio of NLR was 2.69 (95% CI: 1.04-6.97) and 6.58 (95% CI: 1.99-17.75). A prediction model consisting of NLR, age, D-dimer, and simplified PE severity index had an area under the curve of 0.809 (95% CI: 0.738-0.88), a sensitivity of 0.638 (95% CI: 0.511-0.745), and a specificity of 0.851 (95% CI: 0.709-0.917). Net reclassification index (12%, P = 0.035) and integrated discrimination improvement (17%, P = 0.022) indicated an improvement caused by NLR.

CONCLUSIONS

Prognostic value of NLR for PE was confirmed by meta-analysis and validated in an independent cohort, deserving further clinical application.

Co-existence of OSA and respiratory diseases and the influence of gender

INTRODUCTION

Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), is commonly associated with respiratory diseases, such as COPD, asthma and interstitial lung disease.

AREAS COVERED

This narrative review aims to comprehensively synthesize the existing information on SDB in respiratory diseases, investigate the role of gender in this association, and highlight the importance of OSA management in improving sleep, quality of life, and disease prognosis in these specific patient populations.

EXPERT OPINION

Research indicates a synergistic link between OSA and chronic respiratory diseases, which leads to greater morbidity and mortality compared to each disorder alone. Given the lack of an optimal OSA screening tool for these patients, a comprehensive patient approach and overnight diagnostic sleep study are imperative. Despite the limited evidence available, it seems that gender has an impact on the prevalence, severity, and susceptibility of this coexistence. Recognizing the role of gender in the coexistence of OSA and other respiratory diseases can enhance everyday medical practice and enable clinicians to adopt a more personalized approach toward optimal screening and diagnosis of these patients.

Impact of Obstructive Sleep Apnea on Disease Severity and Adverse Outcomes in Patients with Acute Pulmonary Embolism

Purpose

Acute pulmonary embolism (PE) poses a life-threatening risk with high mortality rates. While the coexistence of PE and obstructive sleep apnea (OSA) is gaining recognition, its influence on PE severity and prognosis remains uncertain. This study aims to investigate the associations between OSA and disease severity, as well as outcomes, in patients with acute PE.

Patients and Methods

We conducted a retrospective cohort study on patients diagnosed with acute PE who had undergone previous cardiorespiratory polygraphy. OSA severity was assessed using the apnea-hypopnea index (AHI) derived from cardiorespiratory polygraphy. The severity of acute PE was evaluated using the simplified Pulmonary Embolism Severity Index (sPESI) score. Logistic regression analysis was performed to investigate the associations between AHI and the risk of belonging to the sPESI≥1 group. Cox regression analysis was used to examine the relationship between AHI and long-term adverse events, defined as a composite of all-cause mortality and non-fatal cardiovascular events.

Results

Among 145 acute PE patients (mean age 62.2 years, 49.7% male), 94 (64.8%) had OSA. Patients with OSA had a significantly higher proportion of sPESI≥1 (89.4% vs 68.6%, p=0.002) than non-OSA patients. Each unit increase in AHI was associated with a 15% increased risk of severe PE (sPESI≥1) (odds ratio: 1.15, 95% CI 1.05-1.26, p=0.002) after adjusting for confounders. During a median follow-up of 15.2 months, 27 (18.6%) patients experienced adverse events. Increased AHI independently predicted a higher risk of adverse events (hazard ratio: 1.03, 95% CI: 1.00-1.05, p=0.026), even after adjusting for potential confounders. AHI ≥8 events/h was associated with a significantly higher adjusted hazard ratio of 2.56 (95% CI: 1.15-5.72, p=0.022) for adverse events compared to AHI <8 events.

Conclusion

OSA is common in acute PE patients and is linked to increased disease severity and adverse outcomes. Implementing routine OSA screening and management may aid risk stratification and improve outcomes in acute PE patients.