Predictors of mortality in chronic obstructive pulmonary disease: a systematic review and meta-analysis

Predictive Value of CCQ and its Subdomains for Hospitalized Exacerbations in Chronic Obstructive Pulmonary Disease: A 3-Year Observational Prospective Study

BACKGROUND

The prediction capacity of the Clinical COPD Questionnaire (CCQ) and its functional, symptom, and mental subdomain for COPD hospitalized exacerbation were rarely studied.

OBJECTIVE

To examine the prognostic capacity of the total CCQ and its three subdomains for 3-year COPD hospitalized exacerbations.

METHODS

We analyzed the predictive ability of total CCQ score and its subdomains for hospitalized exacerbations in an observational cohort of 987 subjects with stable COPD from the RealDTC, an ongoing multicenter prospective study. Hospitalized exacerbations were prospectively collected every 6 month for a maximum of 3 years.

RESULTS

The total CCQ and its functional and symptom domain, but not the mental domain, were significantly associated with 3-year hospitalized exacerbations by multivariate Cox regression analysis. The predictive capacity of functional domain was similar to that of the total CCQ, but significantly stronger than the symptom and mental domain by ROC analysis (P < 0.05). ROC curves also showed that the AUC of exacerbation history combined with CCQ functional domain was larger than that of exacerbation history alone (P < 0.0001). Additionally, the predictive value of multivariable models that contains CCQ functional domain was significantly better than the corresponding model without CCQ functional domain (P < 0.05).

CONCLUSIONS

The total CCQ and its functional and symptom domain were independent risk factors of 3-year hospitalized exacerbations. The prognostic capacity of the functional domain was similar to that of total CCQ, and was significantly stronger than the symptom and mental domain. The CCQ functional domain was able to increase the predictive power of exacerbation history and other multivariable prediction models, indicating it may have an important role in the multivariable prediction tool for hospitalized exacerbation, and its combination with other clinical variables might be used as a low-cost approach for assessments of the disease severity and severe exacerbation in COPD patients in the future.

Residential greenness and chronic obstructive pulmonary disease in a large cohort in southern China: Potential causal links, risk trajectories, and mediation pathways

INTRODUCTION

Residential greenness may influence COPD mortality, but the causal links, risk trajectories, and mediation pathways between them remain poorly understood.

OBJECTIVES

We aim to comprehensively identify the potential causal links, characterize the dynamic progression of hospitalization or posthospital risk, and quantify mediation effects between greenness and COPD.

METHODS

This study was conducted using a community-based cohort enrolling individuals aged ≥ 18 years in southern China from January 1, 2009 to December 31, 2015. Greenness was characterized by normalized difference vegetation index (NDVI) around participants' residential addresses. We applied doubly robust Cox proportional hazards model, multi-state model, and multiple mediation method, to investigate the potential causal links, risk trajectories among baseline, COPD hospitalization, first readmission due to COPD or COPD-related complications, and all-cause death, as well as the multiple mediation pathways (particulate matter [PM], temperature, body mass index [BMI] and physical activity) connecting greenness exposure to COPD mortality.

RESULTS

Our final analysis included 581,785 participants (52.52% female; average age: 48.36 [Standard Deviation (SD): 17.56]). Each interquartile range (IQR: 0.06) increase in NDVI was associated with a reduced COPD mortality risk, yielding a hazard ratio (HR) of 0.88 (95 % CI: 0.81, 0.96). Furthermore, we observed per IQR (0.04) increase in NDVI was inversely associated with the risk of multiple transitions (baseline - COPD hospitalization, baseline - death, and readmission - death risks), especially a declined risk of all-cause death after readmission (HR = 0.66 [95 %CI: 0.44, 0.99]). Within the observed association between greenness and COPD mortality, three mediators were identified, namely PM, temperature, and BMI (HR for the total indirect effect: 0.773 [95 % CI: 0.703, 0.851]), with PM showing the highest mediating effect.

CONCLUSIONS

Our findings revealed greenness may be a beneficial factor for COPD morbidity, prognosis, and mortality. This protective effect is primarily attributed to the reduction in PM concentration.

Chronic obstructive pulmonary disease: A narrative synthesis of its hallmarks for palliative care clinicians

Chronic obstructive pulmonary disease (COPD) is a life-limiting condition and the third leading cause of death worldwide. People with COPD experience physical and psychological symptoms and functional limitations that impair their quality of life. Their caregivers face adverse clinical outcomes due to personal, social, and financial demands. As such, recent emphasis has been placed on early referral to palliative care services to enhance prognostic awareness, clarify goals of care, and manage symptoms. In this narrative synthesis of key aspects of COPD care, we propose practical, evidence-based strategies to integrate palliative care principles with conventional disease-directed treatments throughout the illness trajectory. We emphasize the importance of equipping clinicians caring for people with COPD with a thorough understanding of both the inherent disease complexities and the cornerstones of its multimodal management, including palliative care, to address the unique psychosocial and physical needs of this patient population.

Estimation of Predictors of Mortality in Patients with Acute Respiratory Failure Secondary to Chronic Obstructive Pulmonary Disease Admitted in Tertiary Care Center

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and an increased chronic inflammatory response in the airways to noxious particles and gases. More than 10 million individuals in the United States (US) are affected with COPD, the fourth largest cause of mortality. Globally 250 million individuals are affected by COPD. D-dimer, C-reactive protein (CRP), acute physiology and chronic health evaluation (APACHE) II score, and hypoalbuminemia have significant correlation with morbidity, mortality, and risk stratification of hospitalized COPD patients with acute respiratory failure (ARF). The purpose of this study is to assess how well D-dimer, CRP, APACHE II score, and hypoalbuminemia predict death in COPD with ARF.

MATERIALS AND METHODS

A hospital-based prospective research (observational study) was conducted in a tertiary care center. The research was carried out from 1st February 2021, until 1st November 2022. The patients (sample size = 60; 35 survived and 25 died) were taken for detailed personal history, occupational history, chest X-ray, arterial blood gas (ABG) analysis, and thorough clinical examination to identify evidence of COPD. Our study included D-dimer, CRP, APACHE II score, and hypoalbuminemia in hospitalized COPD patients.

RESULTS

In our study, the median D-dimer levels for patients who lived and died were 1,012.34 and 7,222.64, respectively, with a p-value < 0.001. Patients who survived had a mean CRP of 3.56, whereas those who were dead had a value of 12.62. The mean serum albumin levels among survived and dead patients were 3.23 and 2.22, respectively. The mean APACHE II score in survived and dead patients were 9.91 and 28.48, respectively. The APACHE II score has sensitivity and specificity of 96 and 91.4%, respectively, with a critical cutoff of >19. Hypoalbuminemia has sensitivity and specificity of 96 and 65.7%, with a critical cutoff of <3.

CONCLUSION

High levels of CRP, an elevated APACHE II score, elevated levels of D-dimer, and lower levels of serum albumin are all independently related to an increased risk of in-hospital mortality.

Development and validation of a novel AI-derived index for predicting COPD medical costs in clinical practice

Background

Chronic Obstructive Pulmonary Disease (COPD) is a major contributor to global morbidity and healthcare costs. Accurately predicting these costs is crucial for resource allocation and patient care. This study developed and validated an AI-driven COPD Medical Cost Prediction Index (MCPI) to forecast healthcare expenses in COPD patients.

Methods

A retrospective analysis of 396 COPD patients was conducted, utilizing clinical, demographic, and comorbidity data. Missing data were addressed through advanced imputation techniques to minimize bias. The final predictors included interactions such as Age × BMI, alongside Tumor Presence, Number of Comorbidities, Acute Exacerbation frequency, and the DOSE Index. A Gradient Boosting model was constructed, optimized with Recursive Feature Elimination (RFE), and evaluated using 5-fold cross-validation on an 80/20 train-test split. Model performance was assessed with Mean Squared Error (MSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and R-squared (R²).

Results

On the training set, the model achieved an MSE of 0.049, MAE of 0.159, MAPE of 3.41 %, and R² of 0.703. On the test set, performance metrics included an MSE of 0.122, MAE of 0.258, MAPE of 5.49 %, and R² of 0.365. Tumor Presence, Age, and BMI were identified as key predictors of cost variability.

Conclusions

The MCPI demonstrates strong potential for predicting healthcare costs in COPD patients and enables targeted interventions for high-risk individuals. Future research should focus on validation with multicenter datasets and the inclusion of additional socioeconomic variables to enhance model generalizability and precision.

The usefulness of Charlson Comorbidity Index (CCI) scoring in predicting all-cause mortality in Outpatients with Clinical Diagnoses of COPD

Background

Since comorbid conditions are frequently present in chronic obstructive pulmonary disease (COPD) and affect outcome, a composite scoring system to quantify comorbidity might be helpful in assessing mortality risk.

Methods

We tested the hypothesis that the Charlson Comorbidity Index (CCI) score at the time of an outpatient medical clinic encounter for COPD predicts all-cause mortality. Cox Proportional Hazards analyses were used in 200 randomly selected patients to relate CCI scores to all-cause mortality out to 5 years.

Results

Mean age was 62 ± 10 years, 56% were female, FEV1 was 62%, CCI was 3.08 ± 2.30, and 30% had a CCI ≥ 4, indicating 3 or more comorbid conditions. All-cause mortality was 8.5% and 20% at 3 and 5 years, respectively. In univariate testing, the CCI score and hospitalizations predicted mortality, but FEV1 did not. In multivariable testing, which included covariates of age, sex, socioeconomic status, race, FEV1 percent-predicted, and all-cause hospitalizations in the preceding year, CCI expressed as a continuous variable strongly predicted mortality: hazard ratio (HR) 1.38 for each unit increase in the score (p < 0.0001). While 1 or 2 comorbid conditions were not significantly related to mortality, 3 or more comorbid conditions (compared to none) strongly predicted mortality: HR 9.80, 95% CI 3.80 to 25.00.

Conclusion

Comorbidity, assessed with the CCI, is strongly predictive of mortality in outpatients with a clinical diagnosis of COPD, and this relationship appears to be non-linear. This instrument may be useful in determining prognosis in this population.

Temporal trends, gender, and ethnoracial disparities in mortality from pulmonary emphysema: A retrospective nationwide analysis

Emphysema, a significant global health issue, involves abnormal lung enlargement and wall destruction, affecting 9% to 12% of people worldwide. In the United States (US), 2 million people live with emphysema, with numbers expected to rise. Data on mortality trends and disparities associated with demographic factors is limited, underscoring our study's focus on analyzing these patterns in US adults. This study examined death certificates from the CDC WONDER database for individuals aged 25 and older who died with emphysema (J43) between 1999 and 2020. Age-adjusted mortality rates (AAMRs) and annual percent change were calculated by year, gender, age group, race/ethnicity, geographic region, and urbanization status. Between 1999 and 2020, there were 484,095 reported deaths among emphysema patients. The overall AAMR decreased from 18.5 to 7.2 per 100,000 population, with an annual decrease of 8% from 2008 to 2015, followed by a slight recent increase. Analyzing by age groups, older adults had the highest AAMR of 42. Men had significantly higher AAMRs than women (13.4 vs 7.8). By race, non-Hispanic (NH) White patients had the highest AAMRs (11.3), followed by NH American Indian or Alaska Native (8.2), NH Black (7.7), Hispanic (3.9), and NH Asian or Pacific Islander patients (3.1). Nonmetropolitan areas had higher AAMRs compared to metropolitan areas (11.7 vs 9.8). Emphysema mortality has decreased overall but recently increased slightly. Higher rates are seen among older adults, men, NH White patients, and nonmetropolitan residents. Policies are needed to continue reducing these death rates and to address these disparities.

The Impact of Anemia on Long-Term Mortality in Hospitalized Patients with Exacerbation of Chronic Obstructive Pulmonary Disease

Purpose

Anemia is a risk factor for mortality within the general population and is notably prevalent among individuals with chronic obstructive pulmonary disease (COPD). Our objective was to investigate the impact of anemia on the long-term mortality risk of hospitalized COPD patients. Additionally, we aimed to identify the cause of mortality to assess whether it was different in relation to the presence of anemia.

Patients and Methods

This was an observational retrospective analysis of prospectively collected data of consecutive patients admitted because of COPD exacerbation. Clinical characteristics, the presence of anemia, months of survival and cause of death if occurred, were recorded. Patients were categorized into two groups: anemic (for women hemoglobin level < 12 g/dL and for men hemoglobin level < 13 g/dL) and non-anemic. Survival analysis was conducted using Kaplan-Meier curves and Cox proportional hazard regression analysis.

Results

A total of 125 patients (20% women) were included in the study. Among them, 31 (25%) were identified as anemic, By the conclusion of the study, 59 patients (47%) had died: 27 out of 31 anemic patients (87%) and 32 out of 94 non-anemic patients (34%) (p<0.001). Anemia was a robust predictor of mortality one year after admission (adjusted hazard ratio HR; 5.20 [1.86-14.55]); three years after admission (HR 4.30 [2.03-9.10]), and at the study's termination (with a follow-up period ranging from a minimum of 38 months to a maximum of 56 months) (HR; 3.80 [1.96-7.38]). Mortality in the group of patients with anemia was of 27 individuals (87%) and 32 (34%) in patients without anemia (p<0.001). The causes of mortality in patients with or without anemia were similar.

Conclusion

The detection of anemia upon admission for COPD exacerbation serves as a robust predictor of mortality in the subsequent years.

Advance care planning in patients with respiratory failure

Advance care planning (ACP) is a complex and iterative communication process between patients, surrogates and clinicians that defines goals of care that may include, but is not limited to, documentation of advance directives. The aim of ACP is to promote patient-centred care tailored to the patient's clinical situation through informed preparation for the future and improved communication between patient, clinicians and surrogates, if the latter need to make decisions on patient's behalf.The aim of this article is to review research related to ACP in acute and chronic respiratory failure, regarding the process, communication, shared decision-making, implementation and outcomes.Research has produced controversial results on ACP interventions due to the heterogeneity of measures and outcomes, but positive outcomes have been described regarding the quality of patient-physician communication, preference for comfort care, decisional conflict and patient-caregiver congruence of preferences and improved documentation of ACP or advance directives.The main barriers to ACP in chronic respiratory failure are the uncertainty of prognosis (particularly in the organ failure trajectory), the choice of the best timing for initiation and the lack of training of healthcare workers. In acute respiratory failure, the ACP process can be very short, should include the patient whenever possible, and is based on a discussion of treatments appropriate to the patient's functional status prior to the event (e.g. assessment of frailty) and clear communication of the likely consequences of possible options.All healthcare worker dealing with patients with serious illnesses should have training in communication skills to promote engagement in ACP discussions.

The PROgnostic ModEl for chronic lung disease (PRO-MEL): development and temporal validation

BACKGROUND

Patients with chronic lung diseases (CLDs), defined as progressive and life-limiting respiratory conditions, experience a heavy symptom burden as the conditions become more advanced, but palliative referral rates are low and late. Prognostic tools can help clinicians identify CLD patients at high risk of deterioration for needs assessments and referral to palliative care. As current prognostic tools may not generalize well across all CLD conditions, we aim to develop and validate a general model to predict one-year mortality in patients presenting with any CLD.

METHODS

A retrospective cohort study of patients with a CLD diagnosis at a public hospital from July 2016 to October 2017 was conducted. The outcome of interest was all-cause mortality within one-year of diagnosis. Potential prognostic factors were identified from reviews of prognostic studies in CLD, and data was extracted from electronic medical records. Missing data was imputed using multiple imputation by chained equations. Logistic regression models were developed using variable selection methods and validated in patients seen from January 2018 to December 2019. Discriminative ability, calibration and clinical usefulness of the model was assessed. Model coefficients and performance were pooled across all imputed datasets and reported.

RESULTS

Of the 1000 patients, 122 (12.2%) died within one year. Patients had chronic obstructive pulmonary disease or emphysema (55%), bronchiectasis (38%), interstitial lung diseases (12%), or multiple diagnoses (6%). The model selected through forward stepwise variable selection had the highest AUC (0.77 (0.72-0.82)) and consisted of ten prognostic factors. The model AUC for the validation cohort was 0.75 (0.70, 0.81), and the calibration intercept and slope were - 0.14 (-0.54, 0.26) and 0.74 (0.53, 0.95) respectively. Classifying patients with a predicted risk of death exceeding 0.30 as high risk, the model would correctly identify 3 out 10 decedents and 9 of 10 survivors.

CONCLUSIONS

We developed and validated a prognostic model for one-year mortality in patients with CLD using routinely available administrative data. The model will support clinicians in identifying patients across various CLD etiologies who are at risk of deterioration for a basic palliative care assessment to identify unmet needs and trigger an early referral to palliative medicine.

TRIAL REGISTRATION

Not applicable (retrospective study).

A Pilot Study on Proteomic Predictors of Mortality in Stable COPD

Chronic Obstructive Pulmonary Disease (COPD) is the third leading cause of global mortality. Despite clinical predictors (age, severity, comorbidities, etc.) being established, proteomics offers comprehensive biological profiling to obtain deeper insights into COPD pathophysiology and survival prognoses. This pilot study aimed to identify proteomic footprints that could be potentially useful in predicting mortality in stable COPD patients. Plasma samples from 40 patients were subjected to both blind (liquid chromatography-mass spectrometry) and hypothesis-driven (multiplex immunoassays) proteomic analyses supported by artificial intelligence (AI) before a 4-year clinical follow-up. Among the 34 patients whose survival status was confirmed (mean age 69 ± 9 years, 29.5% women, FEV1 42 ± 15.3% ref.), 32% were dead in the fourth year. The analysis identified 363 proteins/peptides, with 31 showing significant differences between the survivors and non-survivors. These proteins predominantly belonged to different aspects of the immune response (12 proteins), hemostasis (9), and proinflammatory cytokines (5). The predictive modeling achieved excellent accuracy for mortality (90%) but a weaker performance for days of survival (Q2 0.18), improving mildly with AI-mediated blind selection of proteins (accuracy of 95%, Q2 of 0.52). Further stratification by protein groups highlighted the predictive value for mortality of either hemostasis or pro-inflammatory markers alone (accuracies of 95 and 89%, respectively). Therefore, stable COPD patients' proteomic footprints can effectively forecast 4-year mortality, emphasizing the role of inflammatory, immune, and cardiovascular events. Future applications may enhance the prognostic precision and guide preventive interventions.

Outcomes and Hospital Service Use Among Patients With COPD in a Nurse- and Allied Health-Led Clinic

Importance

Multidisciplinary disease management efforts enable the improvement in lung function among patients with chronic obstructive pulmonary disease (COPD), but there is little evidence of its association with risks of adverse health outcomes and health care service use.

Objective

To examine the association between the use of a nurse- and allied health-led primary care clinic for respiratory patients, namely the Nurse and Allied Health Clinic-Respiratory Care (NAHC-Respiratory), and their risks of mortality and morbidity and health care service use.

Design, Setting, and Participants

This territory-wide, population-based, propensity-matched, retrospective cohort study used data from the electronic health records of all patients who used public health care services in Hong Kong, China, from January 1, 2010, to December 31, 2019. All patients with COPD treated in public outpatient clinics between January 1, 2010, and December 31, 2014, were included. Patients who attended NAHC-Respiratory and usual care only were propensity score-matched at a 1:2 ratio. Data analyses were conducted between August 2023 and April 2024.

Exposure

Attendance at NAHC-Respiratory.

Main Outcomes and Measures

All-cause and cause-specific mortality, incidence of COPD complications, and use of emergency department and inpatient services until the end of 2019 were compared between the NAHC-Respiratory and usual care participants using Cox proportional hazard regression, Poisson regression, and log-link gamma regression models after matching.

Results

This study included 9048 eligible patients after matching, including 3093 in the exposure group (2814 [91.0%] men; mean [SD] age, 69.8 [9.5] years) and 5955 in the reference group (5431 [91.2%] men; mean [SD] age, 69.5 [11.7] years). Compared with patients in the usual care-only group (reference), patients in the exposure group had lower risks of all-cause mortality (hazard ratio [HR], 0.84; 95% CI, 0.78-0.90) as well as pneumonia-caused (HR, 0.85; 95% CI, 0.74-0.97), respiratory-caused (HR, 0.86; 95% CI, 0.77-0.96), and cardiovascular-caused (HR, 0.74; 95% CI, 0.59-0.93) mortality. Exposure was associated with reduced rates of emergency department visits (incidence rate ratio [IRR], 0.92; 95% CI, 0.86-0.98) and hospitalization through emergency department (IRR, 0.89; 95% CI, 0.83-0.95).

Conclusions

In this cohort study, the use of a nurse- and allied health-led clinic in primary care settings was associated with reduced risks of mortality and use of hospital services among patients with COPD. These findings emphasize the important role of health care workers other than physicians in disease management in the primary care setting. The NAHC-Respiratory model and service components can be used to help improve primary care programs to benefit more patients with COPD.

Prognostic Factors of Mortality in Nonchronic Obstructive Pulmonary Disease Chronic Lung Disease: A Scoping Review

Introduction: Patients with chronic lung disease (CLD) experience a heavy symptom burden at the end of life, but their uptake of palliative care is notably low. Having an understanding of a patient's prognosis would facilitate shared decision making on treatment options and care planning between patients, families, and their clinicians, and complement clinicians' assessments of patients' unmet palliative needs. While literature on prognostication in patients with chronic obstructive pulmonary disease (COPD) has been established and summarized, information for other CLDs remains less consolidated. Summarizing the mortality risk factors for non-COPD CLDs would be a novel contribution to literature. Hence, we aimed to identify and summarize the prognostic factors associated with non-COPD CLDs from the literature. Methods: We conducted a scoping review following published guidelines. We searched MEDLINE, Embase, PubMed, CINAHL, Cochrane Library, and Web of Science for studies published between 2000 and 2020 that described non-COPD CLD populations with an all-cause mortality risk period of up to three years. Only primary studies which reported associations with mortality adjusted through multivariable analysis were included. Results: Fifty-five studies were reviewed, with 53 based on interstitial lung disease (ILD) or connective tissue disease-associated ILD populations and two in bronchiectasis populations. Prognostic factors were classified into 10 domains, with pulmonary function and disease being the largest. Older age, lower forced vital capacity, and lower carbon monoxide diffusing capacity were most commonly investigated and associated with statistically significant increases in mortality risks. Conclusions: This comprehensive overview of prognostic factors for patients with non-COPD CLDs would facilitate the identification and prioritization of candidate factors to predict short-term mortality, supporting tool development for decision making and to identify high-risk patients for palliative needs assessments. Literature focused on patients with ILDs, and more studies should be conducted on other CLDs to bridge the knowledge gap.

Frailty and its influence on mortality and morbidity in COPD: A Systematic Review and Meta-Analysis

Frailty increases vulnerability to adverse outcomes. Long-term conditions increase the risk of frailty. We searched PubMed, Web of Science, The Cochrane Library, EMBASE from inception to March 2022. Quality assessment was conducted using the NOS. Data was analysed in a pooled a random-effects meta-analysis. Our primary outcome was the impact of frailty on mortality in adults with Chronic Obstructive Pulmonary Disease (COPD) diagnosis according to the guidelines. Secondary outcomes were: frailty and association with readmissions, hospitalisations, exacerbation rates, and prevalence of frailty in COPD. We identified 25 studies, with 5882 participants. The median prevalence of frailty was 47% (IQR, 39.3-66.3%, range 6.4-72%). There was an association between COPD patients living with frailty and increased risk of mortality versus COPD patients without frailty (pooled OR, 4.21 (95% CI 2.99-5.93, I2 55%). A descriptive analysis of relationship between frailty and hospital readmission and all cause hospitalization showed positive associations. The relationship between frailty and the risk of exacerbation showed a pooled OR, 1.45 (95% CI 0.37-5.70, I2 80%). Frailty is significantly associated with higher mortality risk in COPD. Frailty is common in patients with COPD and its measurement should be considered in clinical practice to better characterise COPD.

Association between serum phosphate and in-hospital mortality of patients with AECOPD: A retrospective analysis on eICU database

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is an important adverse event in the development of chronic obstructive pulmonary disease (COPD). Hyperphosphatemia is associated with higher mortality in patients with multiple diseases. In this study, we aimed to determine the relationship between serum phosphate and the risk of in-hospital mortality in patients with AECOPD. Methods: In the present study, patients with AECOPD were enrolled in the electronic Intensive Care Unit Collaborative Research Database (eICU-CRD), and divided into three groups according to the tertiles of serum phosphate level. The primary outcome measure was all-cause in-hospital mortality. The association between serum phosphate level and in-hospital mortality was investigated using multivariate logistic regression analysis. Moreover, subgroup analysis was performed to explore whether the relationship was consistent among different subgroups. Results: A total of 1199 AECOPD patients were included in this study. Non-survivors had higher serum phosphate levels than survivors. All patients were classified into lowest tertile, median tertile, and highest tertile, respectively. Multivariate logistic regression analysis indicated that serum phosphate was positively associated with in-hospital mortality after adjusting for confounders. Moreover, there was a significant trend across tertiles when serum phosphate level was diverted as a categorical variable. In addition, subgroup analysis demonstrated that serum phosphate was consistently associated with a higher risk of in-hospital mortality in different subgroups. Conclusion: Higher serum phosphate was positively associated with the increased in-hospital mortality in patients with AECOPD. Hyperphosphatemia may be an underlying high-risk factor for in-hospital mortality owing to AECOPD.

Hematological Parameters for Predicting Mortality in Acute Exacerbation of Chronic Obstructive Pulmonary Disease

(1) Introduction: COPD is a common and serious condition affecting a significant proportion of the population globally. Patients often suffer from exacerbations which lead to the worsening of their health status and respiratory function, and can often lead to death. Quick and cheap investigations are required that are capable of predicting mortality in patients with acute exacerbations that can be applied in low resource settings. (2) Materials and methods: This was a retrospective study carried out using hospital records of patients admitted for AECOPD from 1 January 2017 to 30 November 2022. Chi-square test (for sex) and Student's t-test were used to look for significant associations. Receiver Operating Characteristics (ROC) curves were plotted and Area Under Curve (AUC) values were calculated for various hematological parameters. Youden's J was used to identify the ideal cut-off with optimal sensitivity and specificity. Multivariate Cox regression was used to identify independent hematological predictors of mortality. Kaplan-Meir survival plots for neutrophil lymphocyte ratio (NLR) with the optimal cut-off were plotted. (3) Results: Amongst the 500 patients, 42 died while 458 survived, giving a mortality rate of 8.4%. NLR had the strongest association with mortality. The cut-off for various parameters were: NLR 14.83 (AUC 0.73), total leukocyte count (TLC) 13,640 cells/mm³ (AUC 0.60), absolute neutrophil count (ANC) 12,556 cells/mm³ (AUC 0.62), derived NLR (dNLR) 9.989 (AUC 0.73), hemoglobin 11.8 mg/dL (AUC 0.59), packed cell volume (PCV) 36.6% (AUC 0.60), and platelet lymphocyte ratio (PLR) 451.32 (AUC 0.55). (4) Conclusions: In patients with acute exacerbation of COPD, NLR was strongly associated with mortality, followed by dNLR. Cox regression identified NLR as an independent predictor of mortality.

Supplemental oxygen and noninvasive ventilation

The respiratory system attempts to maintain normal levels of oxygen and carbon dioxide. However, airflow limitation, parenchymal abnormalities and dysfunction of the respiratory pump may be compromised in individuals with advanced COPD, eventually leading to respiratory failure, with reduced arterial oxygen tension (hypoxaemia) and/or increased arterial carbon dioxide tension (P aCO2 ; hypercapnia). Hypoxaemia may persist in individuals with severe COPD despite smoking cessation and optimisation of pharmacotherapy. Long-term oxygen therapy (LTOT) can improve survival in those with severe daytime hypoxaemia, whereas those with less severe hypoxaemia may only have improved exercise capacity and dyspnoea. Changes in respiratory physiology that occur during sleep further predispose to hypoxaemia, particularly in individuals with COPD. However, the major cause of hypoxaemia is hypoventilation. Noninvasive ventilation (NIV) may reduce mortality and need for intubation in individuals with COPD and acute hypercapnic respiratory failure. However, NIV may also improve survival and quality of life in individuals with stable, chronic hypercapnia and is now suggested for those with prolonged hypercapnia (e.g. P aCO2 >55 mmHg 2-6 weeks after hospital discharge) when clinically stable and after optimisation of medical therapy including LTOT if indicated. Many questions remain about the optimal mode, settings and goal of NIV therapy.