Predisposing factors to acquisition of acute respiratory tract infections in the community: a systematic review and meta-analysis

Long-term exposure to air pollution and lower respiratory infections in a large population-based adult cohort in Catalonia

BACKGROUND

Evidence is limited regarding the role of air pollution in acute lower respiratory infections among adults. We assessed the influence of long-term air pollution exposure on hospital admission for lower respiratory infections and whether there are vulnerable subgroups.

METHODS

We used a populational cohort in Catalonia, Spain, comprising 3,817,820 adults residing in Catalonia as of January 1, 2015. Air pollution exposure was assigned to individuaĺs residential address using locally-developed models. We characterized the concentration-response functions between long-term air pollution exposure and hospital admission for lower respiratory infections between 2015 and 2019. We assessed interaction between exposure and clinical and socio-economic factors on multiplicative and additive scales.

RESULTS

An interquartile range exposure increase was associated with an 8 % (95 % Confidence Interval: 5 %-11 %) for Nitrogen Dioxide, 10 % (95 % Confidence Interval: 8 %-13 %) for Particulate Matter with diameter equal to or smaller than 2.5 µm, 5 % (95 % Confidence Interval: 3 %-7%) for Particulate Matter with diameter equal to or smaller than 10 µm and 18 % (95 % Confidence Interval: 14 %-22%) for ozone (adjusted by Nitrogen Dioxide) increase in hospital admissions for respiratory infections. Concentration-response functions were non-linear, with steeper slopes at exposures below the median or at most extreme high values. Associations were consistently greater for individuals over 65 years or with hypertension diagnosis and males.

CONCLUSIONS

Long-term exposure to air pollution was positively associated with hospital admission for lower respiratory infections. Individuals who were older than 65 years, hypertensive or male were most vulnerable.

Non-COVID Respiratory Infections Related Emergency Room Visits Among Autistic Adults in the United States

INTRODUCTION

This is a retrospective study that examines the risk of non-COVID-19 respiratory infection (RI)-related emergency department (ED) visits and hospitalizations among autistic adults. The study compares these findings to non-autistic adults using the 2018 Healthcare Cost and Utilization Project Nationwide Emergency Department Sample.

METHODS

The data were analyzed in 2022 using the ICD-10-CM codes to extract 46,996 case records that included an autism diagonosis matched by age and sex (140,997) records that did not include an autism diagnosis in a 1:3 case-control ratio. Respiratory infections were also identified using the ICD-10-CM codes and classified by type. Logistic regression models were conducted for the likelihood of presenting with respiratory infections to the emergency department and subsequent hospitalization. All models were adjusted for covariates.

RESULTS

Autistic adults were more likely to present with any type of respiratory infection at the emergency department (AOR=1.83, CI=1.69-2.42), lower respiratory infections (AOR=1.37, CI=1.09-1.50), and pneumonia (AOR=2.42, CI=1.98-2.47) compared to non-autistic adults.. They were also more likely to be hospitalized from respiratory infection during emergency department visits (AOR=3.87, CI=3.21-4.30), including upper respiratory infections and lower respiratory infections, pneumonia, and bronchitis.

CONCLUSIONS

Individuals with autism were more likely to experience emergency department visits and hospitalizations because of respiratory infections than individuals without autism. Amid growing evidence of the disproportionate impact of COVID-19 on the autistic population, the study findings highlight a broader, pre-existing burden of respiratory infections among adults with autism in the U.S. that extend beyond the recent pandemic.

Integrated environmental and clinical surveillance for the prevention of acute respiratory infections (ARIs) in indoor environments and vulnerable communities (Stell-ARI): Protocol

The epidemiological relevance of viral acute respiratory infections (ARIs) has been dramatically highlighted by COVID-19. However, other viruses cannot be neglected, such as influenza virus, respiratory syncytial virus, human adenovirus. These viruses thrive in closed spaces, influenced by human and environmental factors. High-risk closed communities are the most vulnerable settings, where the real extent of viral ARIs is often difficult to evaluate, due to the natural disease progression and case identification complexities. During the COVID-19 pandemic, wastewater-based epidemiology has demonstrated its great potential for monitoring the circulation and evolution of the virus in the environment. The "Prevention of ARIs in indoor environments and vulnerable communities" study (Stell-ARI) addresses the urgent need for integrated surveillance and early detection of ARIs within enclosed and vulnerable communities such as long-term care facilities, prisons and primary schools. The rapid transmission of ARIs in such environments underscores the importance of comprehensive surveillance strategies to minimise the risk of outbreaks and safeguard community health, enabling proactive prevention and control strategies to protect the health of vulnerable populations. This study consists of designing and validating tools for integrated clinical and environmental-based surveillance for each setting, coupled with analytical methods for environmental matrices. The clinical surveillance involves specialized questionnaires and nasopharyngeal swabs for virus identification, while the environmental surveillance includes air and surface microbiological and chemical monitoring, and virological analysis of wastewater. Integrating this information and the collection of behavioural and environmental risk factors into predictive and risk assessment models will provide a useful tool for early warning, risk assessment and informed decision-making. The study aims to integrate clinical, behavioural, and environmental data to establish and validate a predictive model and risk assessment tool for the early warning and risk management of viral ARIs in closed and vulnerable communities prior to the onset of an outbreak.

Community-acquired pneumonia: use of clinical characteristics of acutely admitted patients for the development of a diagnostic model - a cross-sectional multicentre study

OBJECTIVES

This study aimed to describe the clinical characteristics of adults with suspected acute community-acquired pneumonia (CAP) on hospitalisation, evaluate their prediction performance for CAP and compare the performance of the model to the initial assessment of the physician.

DESIGN

Cross-sectional, multicentre study.

SETTING

The data originated from the INfectious DisEases in Emergency Departments study and were collected prospectively from patient interviews and medical records. The study included four Danish medical emergency departments (EDs) and was conducted between 1 March 2021 and 28 February 2022.

PARTICIPANTS

A total of 954 patients admitted with suspected infection were included in the study.

PRIMARY AND SECONDARY OUTCOME

The primary outcome was CAP diagnosis assessed by an expert panel.

RESULTS

According to expert evaluation, CAP had a 28% prevalence. 13 diagnostic predictors were identified using least absolute shrinkage and selection operator regression to build the prediction model: dyspnoea, expectoration, cough, common cold, malaise, chest pain, respiratory rate (>20 breaths/min), oxygen saturation (<96%), abnormal chest auscultation, leucocytes (<3.5×109/L or >8.8×109/L) and neutrophils (>7.5×109/L). C reactive protein (<20 mg/L) and having no previous event of CAP contributed negatively to the final model. The predictors yielded good prediction performance for CAP with an area under the receiver-operator characteristic curve (AUC) of 0.85 (CI 0.77 to 0.92). However, the initial diagnosis made by the ED physician performed better, with an AUC of 0.86 (CI 84% to 89%).

CONCLUSION

Typical respiratory symptoms combined with abnormal vital signs and elevated infection biomarkers were predictors for CAP on admission to an ED. The clinical value of the prediction model is questionable in our setting as it does not outperform the clinician's assessment. Further studies that add novel diagnostic tools and use imaging or serological markers are needed to improve a model that would help diagnose CAP in an ED setting more accurately.

TRIAL REGISTRATION NUMBER

NCT04681963.

Within-episode repeat antibiotic prescriptions in patients with respiratory tract infections: A population-based cohort study

BACKGROUND

Antimicrobial stewardship interventions mainly focus on initial antibiotic prescriptions, with few considering within-episode repeat prescriptions. We aimed to describe the magnitude, type and determinants of within-episode repeat antibiotic prescriptions in patients presenting to primary care with respiratory tract infections (RTIs).

METHODS

We conducted a population-based cohort study among 530 sampled English general practices within the Clinical Practice Research Datalink (CPRD). All individuals with a primary care RTI consultation for which an antibiotic was prescribed between March 2018 and February 2022. Main outcome measurement was repeat antibiotic prescriptions within 28 days of a RTI visit stratified by age (children vs. adults) and RTI type (lower vs. upper RTI). Multivariable logistic regression and principal components analyses were used to identify risk factors and patient clusters at risk for within-episode repeat prescriptions.

FINDINGS

905,964 RTI episodes with at least one antibiotic prescription were identified. In adults, 19.9% (95% CI 19.3-20.5%) had at least one within-episode repeat prescription for a lower RTI, compared to 10.5% (95% CI 10.3-10.8%) for an upper RTI. In children, this was around 10% irrespective of RTI type. The majority of repeat prescriptions occurred a median of 10 days after the initial prescription and was the same antibiotic class in 48.3% of cases. Frequent RTI related GP visits and prior within-RTI-episode repeat antibiotic prescriptions were main factors associated with repeat prescriptions in both adults and children irrespective of RTI type. Young (<2 years) and older (65+) age were associated with repeat prescriptions. Among those aged 2-64 years, allergic rhinitis, COPD and oral corticosteroids were associated with repeat prescriptions.

INTERPRETATIONS

Repeat within-episode antibiotic use accounts for a significant proportion of all antibiotics prescribed for RTIs, with same class antibiotics unlikely to confer clinical benefit and is therefore a prime target for future antimicrobial stewardship interventions.

Impact of sex on humoral immunity with live influenza B virus vaccines in mice

Influenza B virus (FLUBV) poses a significant infectious threat, with frequent vaccine mismatch limiting its effectiveness. Our previous work investigated the safety and efficacy of modified live attenuated FLUBV vaccines with rearranged genomes (FluB-RAM and FluB-RANS) or a temperature-sensitive PB1 segment with a C-terminal HA tag (FluB-att). In this study, we compared the immune responses of female and male DBA/2J mice vaccinated with these vaccines, including versions containing a chimeric HA segment with an N-terminal IgA-inducing peptide (IGIP). Importantly, both recombinant viruses with and without IGIP remained genetically stable during egg passage. We found that introducing IGIP strengthened vaccine attenuation, particularly for FluB-RAM/IGIP. Prime-boost vaccination completely protected mice against lethal challenge with a homologous FLUBV strain. Notably, recombinant viruses induced robust neutralizing antibody responses (hemagglutination inhibition titers ≥40) alongside antibodies against NA and NP. Interestingly, female mice displayed a consistent trend of enhanced humoral and cross-reactive IgG and IgA responses against HA, NA, and NP compared to male counterparts, regardless of the vaccine used. However, the presence of IGIP generally led to lower anti-HA responses but higher anti-NA and anti-NP responses, particularly of the IgA isotype. These trends were further reflected in mucosal and serological responses two weeks after challenge, with clear distinctions based on sex, vaccine backbone, and IGIP inclusion. These findings hold significant promise for advancing the development of universal influenza vaccines.

Necroptosis in Pneumonia: Therapeutic Strategies and Future Perspectives

Pneumonia remains a major global health challenge, necessitating the development of effective therapeutic approaches. Recently, necroptosis, a regulated form of cell death, has garnered attention in the fields of pharmacology and immunology for its role in the pathogenesis of pneumonia. Characterized by cell death and inflammatory responses, necroptosis is a key mechanism contributing to tissue damage and immune dysregulation in various diseases, including pneumonia. This review comprehensively analyzes the role of necroptosis in pneumonia and explores potential pharmacological interventions targeting this cell death pathway. Moreover, we highlight the intricate interplay between necroptosis and immune responses in pneumonia, revealing a bidirectional relationship between necrotic cell death and inflammatory signaling. Importantly, we assess current therapeutic strategies modulating necroptosis, encompassing synthetic inhibitors, natural products, and other drugs targeting key components of the programmed necrosis pathway. The article also discusses challenges and future directions in targeting programmed necrosis for pneumonia treatment, proposing novel therapeutic strategies that combine antibiotics with necroptosis inhibitors. This review underscores the importance of understanding necroptosis in pneumonia and highlights the potential of pharmacological interventions to mitigate tissue damage and restore immune homeostasis in this devastating respiratory infection.

Social network and severe lower respiratory tract infections in older adults: findings from a Swedish longitudinal population-based study

OBJECTIVES

To investigate the association between social network and the risk and prognosis of severe lower respiratory tract infections (LRTIs) in older adults.

METHODS

Data from Swedish hospital records were matched with the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K). Social network was operationalized as social connections and social support, based on different self-reported variables, and categorized as low, medium, and high. The risk of severe LRTI and related outcomes were assessed using Cox, Poisson, and logistic regression models where appropriate.

RESULTS

A total of 362 individuals experienced LRTI-related hospitalizations between 2001 and 2016 (479 total hospitalizations). High levels of social support decreased the hazard of incident LRTI by 29% (hazard ratio 0.71, 95% confidence interval [CI] 0.52-0.96), the hospital length of stay by 21% (incidence rate ratio 0.79, 95% CI 0.65-0.97), and the risk of 30-day mortality by 92% (odds ratio 0.08, 95% CI 0.01-0.68), but was a risk factor for 30-day readmission (odds ratio 3.16, 95% CI 1.38-7.24). High levels of social connections were associated with a higher risk of incident LRTI in women and those with dementia and/or slow walking speed (P_interaction <0.05).

CONCLUSION

Older individuals' quality of social support seems to be a stronger determinant of LRTI incidence and prognosis than the quantity of their social connections. These findings may inform evidence-based policies aimed at preventing LRTIs in older adults.

Risk factors for community-acquired respiratory infections in a non-pandemic context: Secondary analysis of the PRIMIT study

OBJECTIVES

Respiratory tract infection (RTI) incidence varies between people, but little is known about why. The aim of this study is therefore to identify risk factors for acquiring RTIs.

METHODS

We conducted a secondary analysis of 16,908 participants in the PRIMIT study, a pre-pandemic randomised trial showing handwashing reduced incidence of RTIs in the community. Data was analysed using multivariable logistic regression analyses of self-reported RTI acquisition.

RESULTS

After controlling for handwashing, RTI in the previous year (1 to 2 RTIs: adjusted OR 1.96, 95% CI 1.79 to 2.13, p<0.001; 3 to 5 RTIs: aOR 3.89, 95% CI 3.49 to 4.33, p<0.001; ≥6 RTIs: OR 5.52, 95% CI 4.37 to 6.97, p<0.001); skin conditions that prevent handwashing (aOR 1.39, 95% CI 1.24 to 1.55, p<0.001); children under 16 years in the household (aOR 1.27, 95% CI 1.12, 1.43, p<0.001); chronic lung condition (aOR 1.16, 95% CI 1.02 to 1.32, p = 0.026); female sex (aOR 1.10, 95% CI 1.03 to 1.18, p = 0.005), and post-secondary education (aOR 1.09, 95% CI 1.02 to 1.17, p = 0.01) increased the likelihood of RTI. Those over the age of 65 years were less likely to develop an infection (aOR 0.89, 95% CI 0.82 to 0.97, p = 0.009). Household crowding and influenza vaccination do not influence RTI acquisition. A post-hoc exploratory analysis found no evidence these subgroups differentially benefited from handwashing.

CONCLUSIONS

Previous RTIs, chronic lung conditions, skin conditions that prevent handwashing, and the presence of household children predispose to RTI acquisition. Further research is needed to understand how host and microbial factors explain the relationship between previous and future RTIs.

Sex and gender differences in community-acquired pneumonia

Awareness of the influence of sex ands gender on the natural history of several diseases is increasing. Community-acquired pneumonia (CAP) is the most common acute respiratory disease, and it is associated with both morbidity and mortality across all age groups. Although a role for sex- and gender-based differences in the development and associated complications of CAP has been postulated, there is currently high uncertainty on the actual contribution of these factors in the epidemiology and clinical course of CAP. More evidence has been produced on the topic during the last decades, and sex- and gender-based differences have also been extensively studied in COVID-19 patients since the beginning of the SARS-CoV-2 pandemic. This review aims to provide an extensive outlook of the role of sex and gender in the epidemiology, pathogenesis, treatment, and outcomes of patients with CAP, and on the future research scenarios, with also a specific focus on COVID-19.

Descriptive Analysis of Adverse Drug Reactions Reports of the Most Consumed Antibiotics in Portugal, Prescribed for Upper Airway Infections

Adverse drug reactions (ADR) significantly impact mortality and morbidity and lead to high healthcare costs. Reporting ADR to regulatory authorities allows for monitoring the safety and efficacy profile of medicines on the market and for assessing the benefit-risk ratio. This retrospective study aims to characterize the ADR profile of the most consumed antibiotics in Portugal that are prescribed for upper airway infections and submitted to the EudraVigilance database. The variables were analyzed in an exploratory perspective, through absolute and relative frequencies, with emphasis on serious ADR. A total of 59,022 reports were analyzed of which 64.4% were classified as suspected serious ADR. According to serious ADR, the female sex (52.2%) and 18-64 age group (47.5%) prevail. Health professionals reported 87.8% of suspected serious ADR and European Economic Area (EEA) countries represented 50.8% of the reports. "Skin and subcutaneous tissue connections" (15.9%), "general disorders and administrations site conditions" (12%), and "gastrointestinal disorders" (9.8%) are the prevalent system organ classes. In 4.5% of the reports, patients had a fatal outcome. A periodic evaluation of the safety of the antibiotic should be performed to facilitate the development of guidelines and policies to reduce the frequency of serious ADR.

Risk factors for community-acquired pneumonia among inpatients with mental disorders in a tertiary general hospital

INTRODUCTION

Community-acquired pneumonia (CAP) is an important cause of hospitalization and death in patients with mental disorders. It is critical to understand the risk factors of CAP and determine prevention strategies to reduce CAP. The aim of this study is to explore the characteristics of inpatients with mental disorders who have CAP and analyze the risk factors.

METHODS

This retrospective study included 16,934 inpatients with mental disorders who were admitted for the first time to a tertiary general hospital between January 2017 and July 2021 (excluding January 2020-May 2020). Risk factors for CAP were identified by logistic regression analysis after propensity score matching (PSM, 1:4) for age, gender, and BMI.

RESULTS

The CAP rate of inpatients with mental disorders was 1.78%. Inpatients who had CAP had a significantly prolonged hospital stay, and were more often admitted to a closed ward or the ICU. After PSM, the multivariable analysis revealed that clozapine use (OR = 3.212, 95% CI = 1.744-5.915, P < 0.001), schizophrenia spectrum disorder (OR = 2.785, 95% CI = 1.684-4.607, P < 0.001), alcohol consumption (OR = 2.549, 95% CI = 1.586-4.096, P < 0.001), cardiovascular disease (OR = 2.299, 95% CI = 1.362-3.879, P = 0.002), Charlson comorbidity index (CCI) ≥ 3 (OR = 2.092, 95% CI = 1.342-3.260, P = 0.001), organic mental disorder (OR = 1.941, 95% CI = 1.194-3.156, P = 0.007), antipsychotic drug use (OR = 1.886, 95% CI = 1.312-2.711, P = 0.001), unmarried status (OR = 1.720, 95% CI = 1.164-2.541, P = 0.006) and junior high school education (OR = 1.591, 95%CI = 1.010-2.508, P = 0.045) were independent risk factors for CAP in inpatients with mental disorders.

CONCLUSION

CAP was common in inpatients with mental disorders. Patients with mental disorders have unique risk factors for CAP. Further research is required to explore the relationship and mechanism between different mental disorders, antipsychotic drugs and CAP.