Incidence rate of community-acquired pneumonia in adults: a population-based prospective active surveillance study in three cities in South America

Cost-Effectiveness of 20-Valent Pneumococcal Conjugate Vaccine in Argentinean Adults

INTRODUCTION

In Argentina, vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23; PCV13 → PPSV23) has been recommended for all adults aged ≥ 65 years and younger adults with chronic medical ("moderate-risk") or immunocompromising ("high-risk") conditions since 2017. With the approval of a 20-valent PCV (PCV20), we evaluated the cost-effectiveness of PCV20 versus current recommendations for moderate-/high-risk adults aged 18-64 years and all adults 65-99 years.

METHODS

A probabilistic cohort model was used to project lifetime outcomes and costs associated with invasive pneumococcal disease (IPD) and all-cause non-bacteremic pneumonia (NBP), and the expected impact of vaccination. Clinical outcomes were projected annually based on Argentinean data. Economic costs were estimated based on cases and corresponding medical costs (adjusted to 2023 USD) and costs of vaccine and administration. Cost-effectiveness of PCV20 was evaluated versus the current strategy, PCV13 → PPSV23, and alternatively, versus sequentially administered 15-valent PCV and PPSV23 (PCV15 →  PPSV23), and presented as cost per quality-adjusted life year gained; a healthcare system perspective was used. Costs and benefits were discounted at 3%/year.

RESULTS

PCV20 in lieu of PCV13 → PPSV23 among moderate-/high-risk adults aged 18-64 years and all adults 65-99 years (N = 13.4M) prevented 3838 IPD, 4377 inpatient NBP, and 6003 outpatient NBP cases, and 1865 disease-related deaths; relative to PCV15 → PPSV23 the corresponding reductions were 2775, 3285, 4518, and 1348. PCV20 was projected to be the dominant strategy versus PCV13 → PPSV23 and PCV15 → PPSV23 as overall costs were lower by $87.6M and $80.8M, respectively. In probabilistic sensitivity analyses, PCV20 was dominant (i.e., more effective, less costly) in 100% of 1000 simulations.

CONCLUSIONS

Analyses suggest implementing a PCV20 vaccination program in moderate-/high-risk adults aged 18-64 years and all adults ≥ 65 years-in lieu of PCV13 → PPSV23-would yield substantial reductions in pneumococcal disease and would be cost saving to the Argentinean healthcare system.

Sepsis-Related Lung Injury and the Complication of Extrapulmonary Pneumococcal Pneumonia

Globally, sepsis and pneumonia account for significant mortality and morbidity. A complex interplay of immune-molecular pathways underlies both sepsis and pneumonia, resulting in similar and overlapping disease characteristics. Sepsis could result from unmanaged pneumonia. Similarly, sepsis patients have pneumonia as a common complication in the intensive care unit. A significant percentage of pneumonia is misdiagnosed as septic shock. Therefore, our knowledge of the clinical relationship between pneumonia and sepsis is imperative to the proper management of these syndromes. Regarding pathogenesis and etiology, pneumococcus is one of the leading pathogens implicated in both pneumonia and sepsis syndromes. Growing evidence suggests that pneumococcal pneumonia can potentially disseminate and consequently induce systemic inflammation and severe sepsis. Streptococcus pneumoniae could potentially exploit the function of dendritic cells (DCs) to facilitate bacterial dissemination. This highlights the importance of pathogen-immune cell crosstalk in the pathophysiology of sepsis and pneumonia. The role of DCs in pneumococcal infections and sepsis is not well understood. Therefore, studying the immunologic crosstalk between pneumococcus and host immune mediators is crucial to elucidating the pathophysiology of pneumonia-induced lung injury and sepsis. This knowledge would help mitigate clinical diagnosis and management challenges.

Clinical profile analysis and nomogram for predicting in-hospital mortality among elderly severe community-acquired pneumonia patients: a retrospective cohort study

BACKGROUND

Severe community-acquired pneumonia is one of the most lethal forms of CAP with high mortality. For rapid and accurate decisions, we developed a mortality prediction model specifically tailored for elderly SCAP patients.

METHODS

The retrospective study included 2365 elderly patients. To construct and validate the nomogram, we randomly divided the patients into training and testing cohorts in a 70% versus 30% ratio. The primary outcome was in-hospital mortality. Univariate and multivariate logistic regression analyses were used in the training cohort to identify independent risk factors. The robustness of this model was assessed using the C index, ROC and AUC. DCA was employed to evaluate the predictive accuracy of the model.

RESULTS

Six factors were used as independent risk factors for in-hospital mortality to construct the prediction model, including age, the use of vasopressor, chronic renal disease, neutrophil, platelet, and BUN. The C index was 0.743 (95% CI 0.719-0.768) in the training cohort and 0.731 (95% CI 0.694-0.768) in the testing cohort. The ROC curves and AUC for the training cohort and testing cohort (AUC = 0.742 vs. 0.728) indicated a robust discrimination. And the calibration plots showed a consistency between the prediction model probabilities and observed probabilities. Then, the DCA demonstrated great clinical practicality.

CONCLUSIONS

The nomogram incorporated six risk factors, including age, the use of vasopressor, chronic renal disease, neutrophil, platelet and BUN, which had great predictive accuracy and robustness, while also demonstrating clinical practicality at ICU admission.

Herd immunity in older adults from a middle-income country: A time-series trend analysis of community-acquired pneumonia mortality 2003-2017

Background and Aims

Community-acquired pneumonia is responsible for substantial mortality, and pneumococcus is commonly accepted as a major cause of pneumonia, regardless of laboratory confirmation. Child immunization programs have reported success in decreasing pneumonia mortality: directly in young children and indirectly (herd immunity) in unvaccinated adult populations in some countries. We assess changes in mortality trends for all-cause pneumonia in older adults associated with the introduction of pneumococcal vaccination for children in Peru.

Methods

This is a secondary analysis on administrative data collected periodically by the Peruvian Ministry of Health. An observational retrospective time series analysis was conducted using longitudinal population-based data from death certificates in Peru between 2003 and 2017. The time series includes 6 years before and 9 years after the introduction of the pneumococcal-conjugated vaccines in the national child immunization program in 2009. Monthly frequencies and annual rates for all-cause pneumonia deaths in children under 5 years of age and adults over 65 years of age are presented. Linear and quadratic trends are analyzed.

Results

Deaths among older adults accounted for 75.6% of all-cause pneumonia mortality in Peru, with 94.4% of these reporting "pneumonia due to unspecified organism" as the underlying cause of death. Comparing pre- and post-child immunization program periods, annual average mortality rates from unspecified pneumonia decreased by 22.7% in young children but increased by 19.6% in older adults. A linear trend model supports this overall tendency, but a quadratic curve explains the data better.

Conclusion

Pneumococcal-conjugated vaccines are developed using serotypes prevalent in selected countries from less common (invasive) pneumococcal disease and expected to prevent mortality worldwide from widespread (noninvasive) pneumonia. Our results do not support the presence of herd immunity from pneumococcal vaccination of children for community-acquired pneumonia in the increasingly ageing population of Peru. This should direct future research and could influence public health policy.

Cardiovascular Complications in Community-Acquired Pneumonia

Community-acquired pneumonia (CAP) is accountable for high mortality in both pediatric and adult populations worldwide, about one-third of hospitalized patients pass away within a year of being discharged from the facility. The high mortality and morbidity rates are closely related to cardiovascular complications that are consequent or concomitant to the acute episode of pneumonia. An updated perspective on the major pathophysiological mechanisms, prevalence, risk factors, outcomes, and relevant treatments of cardiovascular events in CAP patients is provided in the current study. It is possible to evaluate the pathophysiology of cardiac disease in this population based on plaque-related events, such as acute myocardial infarction, or events unrelated to plaque, such as arrhythmias and heart failure. With an absolute rate of cardiovascular problems ranging broadly from 10% to 30%, CAP raises the risk of both plaque-related and plaque-unrelated events. Both in- and out-patients may experience these issues at admission, throughout hospitalization, or even up to a year following discharge. At long-term follow-up, cardiac events account for more than 30% of deaths in CAP patients, making them a significant cause of mortality. If patients at risk for cardiac events are stratified, diagnostic tools, monitoring, and preventive measures may be applied to these patients. A prospective evaluation of cardioprotective treatments is urgently required from a research point of view.

Validity of the ROX index in predicting invasive mechanical ventilation requirement in pneumonia

Background

The ROX index (Respiratory rate-OXygenation) has been described as a prediction tool to identify the need for invasive mechanical ventilation (IMV) in community-acquired pneumonia (CAP) with acute hypoxaemic respiratory failure treated with high-flow nasal cannula in order to avoid delay of a necessary intubation. However, its use in predicting the need for ventilatory support in hospitalised patients with CAP has not been validated.

Methods

This is a retrospective cohort study including subjects with CAP treated in the general ward, emergency service or intensive care unit of a third-level centre in Cundinamarca, Colombia, between January 2001 and February 2020. The ROX index was estimated as the ratio of oxygen saturation/fraction of inspired oxygen to respiratory rate.

Results

A total of 895 patients were included, of whom 93 (10%) required IMV. The ROX index proved to be a good predictor, presenting an area under the curve of receiver operating characteristics (AUROC) of 0.733 (95% CI 0.671 to 0.795, p<0.001) when determined by pulse oximetry and an AUROC of 0.779 (95% CI 0.699 to 0.859, p<0.001) when estimated by arterial blood gas (ABG) parameters, with an intraclass correlation of 0.894. The estimated cut-off point was 14.8; a score less than 14.8 indicates high risk of requiring IMV.

Conclusion

The ROX index is a good predictor of IMV in hospitalised patients with CAP. It presents good performance when calculated through pulse oximetry and can replace the one calculated by ABG.

Performance of Machine Learning Algorithms for Predicting Adverse Outcomes in Community-Acquired Pneumonia

Background: The ability to assess adverse outcomes in patients with community-acquired pneumonia (CAP) could improve clinical decision-making to enhance clinical practice, but the studies remain insufficient, and similarly, few machine learning (ML) models have been developed.

Objective: We aimed to explore the effectiveness of predicting adverse outcomes in CAP through ML models.

Methods: A total of 2,302 adults with CAP who were prospectively recruited between January 2012 and March 2015 across three cities in South America were extracted from DryadData. After a 70:30 training set: test set split of the data, nine ML algorithms were executed and their diagnostic accuracy was measured mainly by the area under the curve (AUC). The nine ML algorithms included decision trees, random forests, extreme gradient boosting (XGBoost), support vector machines, Naïve Bayes, K-nearest neighbors, ridge regression, logistic regression without regularization, and neural networks. The adverse outcomes included hospital admission, mortality, ICU admission, and one-year post-enrollment status.

Results: The XGBoost algorithm had the best performance in predicting hospital admission. Its AUC reached 0.921, and accuracy, precision, recall, and F1-score were better than those of other models. In the prediction of ICU admission, a model trained with the XGBoost algorithm showed the best performance with AUC 0.801. XGBoost algorithm also did a good job at predicting one-year post-enrollment status. The results of AUC, accuracy, precision, recall, and F1-score indicated the algorithm had high accuracy and precision. In addition, the best performance was seen by the neural network algorithm when predicting death (AUC 0.831).

Conclusions: ML algorithms, particularly the XGBoost algorithm, were feasible and effective in predicting adverse outcomes of CAP patients. The ML models based on available common clinical features had great potential to guide individual treatment and subsequent clinical decisions.

Incidence, aetiology and serotype coverage for pneumococcal vaccines of community-acquired pneumonia in adults: a population-based prospective active surveillance study in Brazil

OBJECTIVES

To determine the incidence, aetiology and pneumococcal serotype distribution of community-acquired pneumonia (CAP) in Brazilian adults during a 2-year period.

DESIGN

Prospective population-based surveillance study.

SETTING

Patients from two emergency hospitals in Brazil were consecutively included in this study.

PARTICIPANTS

A total of 111 adults aged 50 years and older with radiographically-confirmed CAP requiring an emergency department visit were prospectively enrolled between January 2018 and January 2020.

MAIN OUTCOME MEASURES

Incidence rates of CAP were calculated according to age and pathogen. Pathogens were identified by conventional microbiological methods. Additionally, a novel, Luminex-based serotype specific urinary antigen detection assay was used to detect serotypes included in pneumococcal vaccines.

RESULTS

Mean age of participants was 64 years and 31% were aged ≥70 years. Aetiology was established in 61 (57%) patients; among identified cases, the most common pathogens were Streptococcus pneumoniae (42/61, 69%) and influenza (4/61, 7%). Among serotypes identified from the 42 cases of pneumococcal CAP, estimated coverage ranged by pneumococcal vaccine formulations from 47.6% (13-valent), 59.5% (20-valent, licenced in the USA only) and 71.4% (23-valent). In patients with CAP, 20-valent pneumococcal vaccine serotypes were identified 2.5 times more frequently than 10-valent pneumococcal vaccine serotypes (22.5% vs 9.0%). The incidence rate for CAP in adults aged ≥50 years was 20.1 per 10 000 person-years. In general, the incidence of CAP increased consistently with age, reaching 54.4 (95% CI 36.8 to -76.6) per 10 000 in adults 80 years or older.

CONCLUSIONS

We observed a high burden of pneumococcal CAP among adults in Brazil. Despite the routine immunisation of children and high-risk adults against pneumococcal disease in the Brazilian national vaccination programme, a persistent burden of pneumococcal CAP caused by vaccine serotypes remains in this population.

Halim FS, Rehman AU, Hussain R. Adherence to National Antimicrobial Guidelines in Hospitalized Geriatric Patients with Community-Acquired Pneumonia: A Prospective Observational study in a Malaysian Hospital

The evaluation of disease progression and onsite therapeutic care choices for community-acquired pneumonia (CAP) patients is vital for their well-being and the optimum utilization of healthcare resources. The current study was conducted to assess physicians’ adherence to clinical practice standards and antibiotic prescribing behavior for the treatment of CAP in older people. A prospective study that included 121 consecutive patients admitted for CAP was conducted at Kulim Hospital, Kedah, from March 2020 to August 2020. Medical records including demographic data, comorbidity, physical examination, laboratory or radiologic findings, and drugs used for the treatment of CAP were accessed from bed head tickets (BHT). The mean age for patients was 73.5 ± 6.2 years, 73 (60.3%) and 48 (39.6%) were males and females, respectively. Amoxicillin/clavulanate (19.8%) was the most prescribed antibiotic for non-severe pneumonia followed by ampicillin sodium/sulbactam sodium (6.6%), while in patients with severe CAP beta-lactam + beta lactamase inhibitors (BLIs) with a combination of macrolide were the most common antibiotics prescribed either in patients with (21.4%) or without co-morbidities (8.2%). The average length of stay in the hospital with severe pneumonia was 6–7 days for 23.9% of patients and < 5 days for 21.4% of patients. The duration of intravenous antibiotics in patients with severe pneumonia was 6–7 days for 32.2% of patients. The present findings revealed the adherence of antibiotic prescribing practices to the Malaysian National Antimicrobial Guideline 2019 for CAP therapy among geriatric patients and adherence to the CAP criteria for hospital admissions.

The Performance of CURB-65 and PSI for Predicting In-Hospital Mortality of Community-Acquired Pneumonia in Patients with Type 2 Diabetes Compared with the Non-Diabetic Population

OBJECTIVE

To compare the performance of CURB-65 and Pneumonia Severity Index (PSI) for predicting in-hospital mortality of community-acquired pneumonia (CAP) between patients with and without type 2 diabetes (T2DM).

METHODS

A retrospective study was conducted on 2365 CAP patients in The First Hospital of Qinhuangdao, China. The primary outcome was in-hospital mortality. The area under curves (AUCs) was used to evaluate the abilities of CRB-65, CURB-65, and PSI class for predicting in-hospital mortality in patients with CAP.

RESULTS

Among CAP patients, 127 patients (5.4%) died, 80 patients were without diabetes, and 47 patients had T2DM. In-hospital mortality increased with the risk stratification defined as CURB-65 and PSI class in both non-diabetes and T2DM patients (P<0.05). The AUCs for predicting in-hospital mortality were 0.728～0.798 in patients without T2DM (CRB-65: 0.728, CURB-65: 0.757 and PSI class: 0.798) and 0.641～0.716 in patients with T2DM (CRB-65: 0.641, CURB-65: 0.677 and PSI class: 0.716)(P<0.001). The AUC of the PSI class was lower in patients with T2DM than in patients without T2DM (P<0.05).

CONCLUSION

CURB-65 and PSI class are correlated with in-hospital mortality of CAP in patients with and without T2DM. Compared with non-diabetes patients, the predictive performance of CURB-65 and PSI class decreased in patients with T2DM. A prediction model for evaluating the CAP severity in the T2DM population should be developed by future studies.

Burden of Community-Acquired Pneumonia and Unmet Clinical Needs

Community-acquired pneumonia (CAP) is the leading cause of death among infectious diseases and an important health problem, having considerable implications for healthcare systems worldwide. Despite important advances in prevention through vaccines, new rapid diagnostic tests and antibiotics, CAP management still has significant drawbacks. Mortality remains very high in severely ill patients presenting with respiratory failure or shock but is also high in the elderly. Even after a CAP episode, higher risk of death remains during a long period, a risk mainly driven by inflammation and patient-related co-morbidities. CAP microbiology has been altered by new molecular diagnostic tests that have turned viruses into the most identified pathogens, notwithstanding uncertainties about the specific role of each virus in CAP pathogenesis. Pneumococcal vaccines also impacted CAP etiology and thus had changed Streptococcus pneumoniae circulating serotypes. Pathogens from specific regions should also be kept in mind when treating CAP. New antibiotics for CAP treatment were not tested in severely ill patients and focused on multidrug-resistant pathogens that are unrelated to CAP, limiting their general use and indications for intensive care unit (ICU) patients. Similarly, CAP management could be personalized through the use of adjunctive therapies that showed outcome improvements in particular patient groups. Although pneumococcal vaccination was only convincingly shown to reduce invasive pneumococcal disease, with a less significant effect in pneumococcal CAP, it remains the best therapeutic intervention to prevent bacterial CAP. Further research in CAP is needed to reduce its population impact and improve individual outcomes.

Factors associated with in-hospital mortality from community-acquired pneumonia in Portugal: 2000-2014

Background

Community-acquired pneumonia (CAP) is one of the leading causes of morbidity and mortality worldwide, often leading to hospital admissions. In Portugal, the factors associated with in-hospital mortality due to CAP are not fully documented. The aim of this study was to characterize the trends of CAP hospitalization in all age groups and the factors associated with their mortality between 2000 and 2014.

Methods

We conducted a cross-sectional study using CAP hospitalization data in all age groups, in Portugal Mainland. Logistic regression was used to identify the factors associated with in-hospital mortality.

Results

Between 2001 and 2011, CAP hospitalization rate increased from 2.8 to 4.3 per 1000 population. Hospitalization rates were higher in the extreme ages ( ≤ 4 and  ≥ 75 years). However, a decrease in the hospitalization rate and its mortality was observed, in the younger ages.

A total of 548,699 hospitalization CAP episodes, between 2000 and 2014, were analyzed, with male (56.2%) and elderly ≥65 years (91.7%) predominance, resulting in 101,740 deaths (18.5%). Men had a significantly lower mean age (64.3 ± 26.4 years versus 67.9 ± 27.5 years; p < 0.001). During the studied 15 years, there was an increase of 45.2% in the number of annual hospitalizations, concomitant with the admission increase of individuals aged over 75 years. Since 2012 a decrease in hospitalizations and associated deaths were detected.

The increase in age represented a progressive and significant rise in the probability of death, except for the age group 1–4 years. The age group ≥85 years old (Adjusted OR = 124.256; 95%CI: 97.838–157.807) and males (Adjusted OR = 1.261; 95%CI: 1.243–1.280) were significantly associated with death risk for CAP hospitalization. After 2010, this risk decreased (Adjusted OR = 0.961; 95%CI: 0.940–0.982). The main factors affecting mortality were age, sex, unemployment rate, number of performed procedures and admission quinquennia.

Conclusions

Despite a trend of decrease in CAP hospitalizations and associated death since 2012, the numbers of in-hospital mortality showed, in the 15 years under analysis, an overall increase over time, mainly associated with age, in particular very old people ( ≥ 75 years), males and a higher parish unemployment rate. Therefore, the implementation of CAP preventive measures should be reinforced in these vulnerable groups.

Age, Pulse, Urea and Albumin (APUA) Model: A Tool for Predicting in-Hospital Mortality of Community-Acquired Pneumonia Adapted for Patients with Type 2 Diabetes

OBJECTIVE

The aim of this study was to develop a tool for predicting in-hospital mortality of community-acquired pneumonia (CAP) in patients with type 2 diabetes (T2DM).

METHODS

A retrospective study was conducted on 531 CAP patients with T2DM at The First Hospital of Qinhuangdao. The primary outcome was in-hospital mortality. Variables to develop the nomogram were selected using multiple logistic regression analysis. Discrimination was evaluated using receiver operating characteristic (ROC) curve. Calibration was evaluated using the Hosmer-Lemeshow test and calibration plot.

RESULTS

Multiple logistic regression analysis showed that age, pulse, urea and albumin (APUA) were independent risk predictors. Based on these results, we developed a nomogram (APUA model) for predicting in-hospital mortality of CAP in T2DM patients. In the training set, the area under the curve (AUC) of the APUA model was 0.814 (95% CI: 0.770-0.853), which was higher than the AUCs of albumin alone, CURB-65 and Pneumonia Severity Index (PSI) class (p<0.05). The Hosmer-Lemeshow test (χ ²=5.298, p=0.808) and calibration plot (p=0.802) showed excellent agreement between the predicted possibility and the actual observation in the APUA model. The results of the validation set were similar to those of the training set.

CONCLUSION

The APUA model is a simple and accurate tool for predicting in-hospital mortality of CAP, adapted for patients with T2DM. The predictive performance of the APUA model was better than CURB-65 and PSI class.

Biomarkers in Pneumonia-Beyond Procalcitonin

Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the burden of antibiotic consumption. Due to the complexity of its pathophysiology, it is widely accepted that clinical diagnosis and prognosis are inadequate for the accurate assessment of the severity of the disease. The most challenging task for a physician is the risk stratification of patients with community-acquired pneumonia. Herein, early diagnosis is essential in order to reduce hospitalization and mortality. Procalcitonin and C-reactive protein remain the most widely used biomarkers, while interleukin 6 has been of particular interest in the literature. However, none of them appear to be ideal, and the search for novel biomarkers that will most sufficiently predict the severity and treatment response in pneumonia has lately intensified. Although our insight has significantly increased over the last years, a translational approach with the application of genomics, metabolomics, microbiomics, and proteomics is required to better understand the disease. In this review, we discuss this rapidly evolving area and summarize the application of novel biomarkers that appear to be promising for the accurate diagnosis and risk stratification of pneumonia.

Disease Burden and Etiologic Distribution of Community-Acquired Pneumonia in Adults: Evolving Epidemiology in the Era of Pneumococcal Conjugate Vaccines

Pneumonia is the leading cause of morbidity and mortality, particularly in old adults. The incidence and etiologic distribution of community-acquired pneumonia is variable both geographically and temporally, and epidemiology might evolve with the change of population characteristics and vaccine uptake rates. With the increasing prevalence of chronic medical conditions, a wide spectrum of healthcare-associated pneumonia could also affect the epidemiology of community-acquired pneumonia. Here, we provide an overview of the epidemiological changes associated with community-acquired pneumonia over the decades since pneumococcal conjugate vaccine introduction.