The association between oral bacteria, the cough reflex and pneumonia in patients with acute stroke and suspected dysphagia

Development of a model to predict the risk of multi-drug resistant organism infections in ruptured intracranial aneurysms patients with hospital-acquired pneumonia in the neurological intensive care unit

OBJECTIVE

This study was developed to explore the incidence of multi-drug resistant organism (MDRO) infections among ruptured intracranial aneurysms(RIA) patient with hospital-acquired pneumonia(HAP) in the neurological intensive care unit (NICU), and to establish risk factors related to the development of these infections.

METHODS

We collected clinical and laboratory data from 328 eligible patients from January 2018 to December 2022. Bacterial culture results were used to assess MDRO strain distributions, and risk factors related to MDRO infection incidence were identified through logistic regression analyses. These risk factors were further used to establish a predictive model for the incidence of MDRO infections, after which this model underwent internal validation.

RESULTS

In this study cohort, 26.5 % of RIA patients with HAP developed MDRO infections (87/328). The most common MDRO pathogens in these patients included Multidrug-resistant Klebsiella pneumoniae (34.31 %) and Multidrug-resistant Acinetobacter baumannii (27.45 %). Six MDRO risk factors, namely, diabetes (P = 0.032), tracheotomy (P = 0.004), history of mechanical ventilation (P = 0.033), lower albumin levels (P < 0.001), hydrocephalus (P < 0.001) and Glasgow Coma Scale (GCS) score ≤8 (P = 0.032) were all independently correlated with MDRO infection incidence. The prediction model exhibited satisfactory discrimination (area under the curve [AUC], 0.842) and calibration (slope, 1.000), with a decision curve analysis further supporting the clinical utility of this model.

CONCLUSIONS

In summary, risk factors and bacterial distributions associated with MDRO infections among RIA patients with HAP in the NICU were herein assessed. The developed predictive model can aid clinicians to identify and screen high-risk patients for preventing MDRO infections.

Oral Microbiome Dysbiosis as a Risk Factor for Stroke: A Comprehensive Review

Stroke represents a significant global health burden, with a substantial impact on mortality, morbidity, and long-term disability. The examination of stroke biomarkers, particularly the oral microbiome, offers a promising avenue for advancing our understanding of the factors that contribute to stroke risk and for developing strategies to mitigate that risk. This review highlights the significant correlations between oral diseases, such as periodontitis and caries, and the onset of stroke. Periodontal pathogens within the oral microbiome have been identified as a contributing factor in the exacerbation of risk factors for stroke, including obesity, dyslipidemia, atherosclerosis, hypertension, and endothelial dysfunction. The alteration of the oral microbiome may contribute to these conditions, emphasizing the vital role of oral health in the prevention of cardiovascular disease. The integration of dental and medical health practices represents a promising avenue for enhancing stroke prevention efforts and improving patient outcomes.

The relationship between oral frailty and oral dysbiosis among hospitalized patients aged older than 50 years

OBJECTIVE

This study aimed to clarify the relationship between oral frailty and oral dysbiosis among hospitalized patients aged ≥ 50 years.

METHODS

A prospective observational study was conducted. Number of teeth, masticatory ability, articulatory oral motor skill, tongue pressure, swallowing pressure, and choking were used to assess oral frailty. Saliva samples were collected from the oral cavity for bacterial culture.

RESULTS

A total 103 in patients enrolled and 53.4% suffered from oral frailty. Oral frailty was found to have a 3.07-fold correlation with the presence of Enterobacterales in the oral cavity (p = 0.037), especially in poor articulatory oral motor skill, which showed at greater risk of Enterobacterales isolated from the oral cavity by 5.58-fold (p = 0.01).

CONCLUSION

Half of hospitalized patients was found to have oral frailty that was related to more Enterobacterales in the oral cavity. This evidence suggests that the enhancement of articulatory oral motor skills may serve as a potential strategy for mitigating the presence of Enterobacterales within the oral cavity.

Dysphagia after stroke: research advances in treatment interventions

After a stroke, most patients have dysphagia, which can lead to aspiration pneumonia, malnutrition, and adverse functional outcomes. Protective interventions aimed at reducing these complications remain the cornerstone of treatment. Dietary adjustments and oral hygiene help mitigate the risk of aspiration pneumonia, and nutritional supplementation, including tube feeding, might be needed to prevent malnutrition. Rehabilitative interventions aim to enhance swallowing function, with different behavioural strategies showing promise in small studies. Investigations have explored the use of pharmaceutical agents such as capsaicin and other Transient-Receptor-Potential-Vanilloid-1 (TRPV-1) sensory receptor agonists, which alter sensory perception in the pharynx. Neurostimulation techniques, such as transcranial direct current stimulation, repetitive transcranial magnetic stimulation, and pharyngeal electrical stimulation, might promote neuroplasticity within the sensorimotor swallowing network. Further advancements in the understanding of central and peripheral sensorimotor mechanisms in patients with dysphagia after a stroke, and during their recovery, will contribute to optimising treatment protocols.

Stroke Phase Is Essential for Pneumonia in Dysphagia Patients After Cerebral Infarction

BACKGROUND

The risk of pneumonia increases after stroke, especially in poststroke dysphagia patients. Propensity score matching (PSM) is a statistical method in SPSS, which can be used to balance the difference between the 2 groups of known factors. Nasogastric tube feeding is an important factor of stroke-associated pneumonia. However, few studies have used PSM to eliminate the effect of confounding factor.

METHODS

Our research was a retrospective case-control study. Retrospective review of the patient database between December 1, 2019, and June 30, 2022, to identify consecutive dysphagia patients after cerebral infarction during hospitalization. An 1:1 PSM in SPSS 25.0 was used to balance nasogastric tube feeding between patients with and without pneumonia. The characteristics of these 2 groups were analyzed. Univariate and binary logistic regression analyses were used to screen the risk factors of dysphagia after cerebral infarction.

RESULTS

After 1:1 PSM, 198 subjects met our criteria and were included in the analysis. Age [odds ratio (OR)=1.047, 95% CI: 1.013-1.081, P =0.006], stroke phase (acute stroke) (OR=5.931, 95% CI: 1.133-31.054, P =0.035), admission National Institutes of Health Stroke Scale score (OR=1.058, 95% CI: 1.004-1.115, P =0.034), and length of hospital stay (OR=1.025, 95% CI: 1.001-1.049, P =0.042) had statistically significant correlation with pneumonia in patients with dysphagia after cerebral infarction.

CONCLUSION

In clinical practice, for the prevention of pneumonia in patients with dysphagia after cerebral infarction, we should pay more attention to admission National Institutes of Health Stroke Scale score, age, and stroke phase, especially in acute cerebral infarction patients.

The assessment of dysphagia after stroke: state of the art and future directions

Dysphagia is a major complication following an acute stroke that affects the majority of patients. Clinically, dysphagia after stroke is associated with increased risk of aspiration pneumonia, malnutrition, mortality, and other adverse functional outcomes. Pathophysiologically, dysphagia after stroke is caused by disruption of an extensive cortical and subcortical swallowing network. The screening of patients for dysphagia after stroke should be provided as soon as possible, starting with simple water-swallowing tests at the bedside or more elaborate multi-consistency protocols. Subsequently, a more detailed examination, ideally with instrumental diagnostics such as flexible endoscopic evaluation of swallowing or video fluoroscopy is indicated in some patients. Emerging diagnostic procedures, technical innovations in assessment tools, and digitalisation will improve diagnostic accuracy in the future. Advances in the diagnosis of dysphagia after stroke will enable management based on individual patterns of dysfunction and predisposing risk factors for complications. Progess in dysphagia rehabilitation are essential to reduce mortality and improve patients' quality of life after a stroke.

A prospective examination of swallow and cough dysfunction after lung transplantation

OBJECTIVES

Swallow and cough dysfunction are possible surgical complications of lung transplantation (LT). We examined voluntary cough strength, sensorimotor reflexive cough integrity, and swallow-related respiratory rate (RR) across swallowing safety and aspiration response groups in recovering LT recipients.

METHODS

Forty-five LT recipients underwent flexible endoscopic evaluation of swallowing indexed by the validated Penetration Aspiration Scale. RR before and after a 3-ounce water drinking task was measured. Voluntary and reflexive cough screening were performed to index motor and sensory outcomes. T-tests, one-way ANOVAs, and chi-square (odds ratios) were used.

RESULTS

60% of patients exhibited laryngeal penetration (n = 27) and 40% demonstrated tracheal aspiration (n = 18); 72% (n = 13) demonstrated silent aspiration. Baseline RR was higher in aspirators versus non-aspirators (26.5 vs. 22.6, p = 0.04) and in silent aspirators compared to non-silent aspirators (27.9 vs. 20.7, p = 0.01). RR change post-swallowing did not differ between aspiration response groups; however, it was significantly higher in aspirators compared to non-aspirators (3 vs. -2, p = 0.02). Compared to non-silent aspirators, silent aspirators demonstrated reduced voluntary cough peak expiratory flow (PEF; 166 vs. 324 L/min, p = 0.01). PEF, motor and urge to cough reflex cough ratings did not differ between aspirators and non-aspirators. Silent aspirators demonstrated a 7.5 times higher odds of failing reflex cough screening compared to non-silent aspirators (p = 0.07).

CONCLUSIONS

During the acute recovery period, all LT participants demonstrated some degree of unsafe swallowing and reduced voluntary cough strength. Silent aspirators exhibited elevated RR, reduced voluntary cough physiologic capacity to defend the airway, and a clinically distinguishable blunted motor response to reflex cough screening.

Management of Aspiration Risk in Stroke

Managing risk for aspiration in the stroke patient will assist to decrease one of the major complications that these patients experience, which is poststroke pneumonia. Using an evidenced-based dysphagia protocol is shown to reduce mortality, morbidity, and length of stay caused by poststroke pneumonia. Physicians, nurses, speech pathologists, and dieticians will be instrumental in performing ongoing assessments and aspiration-prevention strategies to improve stroke patient outcome and reduce complications. Education, and measurement of comprehension, of the care team, patient, and family concerning dysphagia management and prevention of aspiration pneumonia will assist in achieving the aforementioned goals.

Implementation of a free water protocol at a long term acute care hospital

This feasibility study aimed to trial a Free Water Protocol (FWP) for patients with thin liquid dysphagia in the Long-Term Acute Care Hospital (LTACH) setting. Patients with dysphagia are often prescribed thickened liquids to avoid or mitigate aspiration. While this clinical intervention can minimize the risk of aspiration pneumonia (PNA), it is generally not well received by patients. As such, the goal of this study was to determine if patients who knowingly aspirate thin liquids can safely tolerate thin liquid water, and if so, to what degree of benefit. The study assessed for adverse events, fluid intake, hydration status, quality of life, and overall swallow function outcomes. These measurements were taken over a 7 day trial period using inventories, lab work, clinical judgment, and observation. Ten participants were enrolled in this study with 9 having sufficient data for analysis (n = 9). No adverse events related to the FWP were observed, and patients saw improved total fluid intake (P = 0.0074), swallow-related quality of life (P = 0.0273), and overall swallow function (P = 0.0002). The results in this feasibility study allowed for the hospital wide implementation of the FWP and laid out the groundwork for future studies looking at longitudinal effects of a FWP.

The role of the oral microbiome in smoking-related cardiovascular risk: a review of the literature exploring mechanisms and pathways

Cardiovascular disease is a leading cause of morbidity and mortality. Oral health is associated with smoking and cardiovascular outcomes, but there are gaps in knowledge of many mechanisms connecting smoking to cardiovascular risk. Therefore, the aim of this review is to synthesize literature on smoking and the oral microbiome, and smoking and cardiovascular risk/disease, respectively. A secondary aim is to identify common associations between the oral microbiome and cardiovascular risk/disease to smoking, respectively, to identify potential shared oral microbiome-associated mechanisms. We identified several oral bacteria across varying studies that were associated with smoking. Atopobium, Gemella, Megasphaera, Mycoplasma, Porphyromonas, Prevotella, Rothia, Treponema, and Veillonella were increased, while Bergeyella, Haemophilus, Lautropia, and Neisseria were decreased in the oral microbiome of smokers versus non-smokers. Several bacteria that were increased in the oral microbiome of smokers were also positively associated with cardiovascular outcomes including Porphyromonas, Prevotella, Treponema, and Veillonella. We review possible mechanisms that may link the oral microbiome to smoking and cardiovascular risk including inflammation, modulation of amino acids and lipids, and nitric oxide modulation. Our hope is this review will inform future research targeting the microbiome and smoking-related cardiovascular disease so possible microbial targets for cardiovascular risk reduction can be identified.

Factors that influence oral hygiene care with hospitalised stroke patients: a mixed methods study

PURPOSE

Survivors of stroke experience poor oral health during and following hospitalisation. Health professionals consistently report that oral hygiene is complex. Interventions aiming to improve the delivery of oral hygiene care by health professionals rarely use a theoretically driven approach. This study reports the first phase in an intervention development and uses the action, actor, context, target, time (AACTT) framework and theoretical domains framework (TDF) to understand who needs to do what differently in the delivery of oral hygiene care with hospitalised stroke survivors.

METHOD

Mixed methods including analysis of oral health policies and clinical guidelines using the AACTT framework, focus group discussions using the TDF and audit of 60 medical records.

RESULTS

Policies and guidelines lack specificity regarding what oral hygiene care is and who should be responsible. Health professionals have low beliefs in their capabilities and experience numerous contextual barriers. More than 40% of patients had no documented evidence of oral hygiene care.

CONCLUSION

This study used a theoretically driven approach to identify barriers and enablers to health professional delivery of oral hygiene care with stroke survivors. Interventions aiming to improve clinical practice should target beliefs about capabilities, improved access to resources and detailed oral hygiene clinical guidelines.Implications for rehabilitationSurvivors of stroke experience poor oral health which can contribute to further strokes, cardiovascular disease and mortality.Health care professionals report difficulties in delivering oral hygiene care to hospitalised stroke survivors and clinical guidelines lack detail regarding oral health assessments, interventions and training.Interventions aiming to improve the delivery of oral hygiene care should target health professional beliefs about their capabilities using strategies such as behavioural practice.Resources specific to oral hygiene care for more complex patients, including suctioning toothbrushes, should be readily accessible for health professional use.Clinical guidelines and policies on oral hygiene care should include detail about training content, assessments tools and how to adapt information for patients with complex impairments.

Best Practice Recommendations for Dysphagia Management in Stroke Patients: A Consensus from a Portuguese Expert Panel

Dysphagia is frequent after stroke, and it increases the risk of respiratory infection, dehydration and malnutrition, resulting in worse outcomes. Different clinical guidelines present recommendations for the assessment and management of dysphagia in stroke patients in a scattered way. These best practice recommendations address seven clinical questions on the assessment and management of dysphagia in stroke patients, gathering the best-updated evidence. A systematic literature review using the PICO strategy was performed. The recommendations draft was then appraised by a multidisciplinary panel of experts (nutritionists, physiatrists, speech-language pathologists and rehabilitation nurses) in a total of 3 Delphi rounds. A minimum of 80% consensus was established, and the final version offers a total of 21 recommendations for use in clinical practice for stroke patients. These clinical recommendations are an overview of the most recent evidence combined with experts' consensus and translated into clinically relevant statements. In implementing recommendations at the local level, health professionals should identify facilitators and barriers to evidence-based practice within their contexts and determine the best strategies to address local needs. Where the change is needed, initial and continuing training on all recommendations is essential and relevant.

Functional screening of a human saliva metagenomic DNA reveal novel resistance genes against sodium hypochlorite and chlorhexidine

Objective

Many sections of the health care system are facing a major challenge making infectious disease problematic to treat; antimicrobial resistance (AMR). Identification and surveillance of the resistome have been highlighted as one of the strategies to overcome the problem. This study aimed to screen for AMR genes in an oral microbiota, a complex microbial system continuously exposed to antimicrobial agents commonly used in dental practice.

Materials and methods

As a significant part of the oral microbiome cannot be conventionally cultured, a functional metagenomic approach was chosen. The human oral metagenomic DNA was extracted from saliva samples collected from 50 healthy volunteers in Norway. The oral metagenomic library was then constructed by ligating partially digested oral metagenome into pSMART BAC vector and introducing into Escherichia coli. The library was screened against antimicrobials in dental practices. All resistant clones were selected and analyzed.

Results

Screening of the oral metagenomic library against different antimicrobials detected multiple clones with resistance against chlorhexidine, triclosan, erythromycin, tetracycline, and sodium hypochlorite. Bioinformatic analysis revealed both already known resistance genes, including msr, mef(A), tetAB(46), and fabK, and genes that were not previously described to confer resistance, including recA and accB conferring resistance to sodium hypochlorite and chlorhexidine, respectively.

Conclusion

Multiple clones conferring resistance to antimicrobials commonly used in dental practices were detected, containing known and novel resistant genes by functional-based metagenomics. There is a need for more studies to increase our knowledge in the field.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-02000-5.

European Stroke Organisation and European Society for Swallowing Disorders guideline for the diagnosis and treatment of post-stroke dysphagia

Post-stroke dysphagia (PSD) is present in more than 50% of acute stroke patients, increases the risk of complications, in particular aspiration pneumonia, malnutrition and dehydration, and is linked to poor outcome and mortality. The aim of this guideline is to assist all members of the multidisciplinary team in their management of patients with PSD. These guidelines were developed based on the European Stroke Organisation (ESO) standard operating procedure and followed the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. An interdisciplinary working group identified 20 relevant questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence and wrote evidence-based recommendations. Expert opinion was provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found moderate quality of evidence to recommend dysphagia screening in all stroke patients to prevent post-stroke pneumonia and to early mortality and low quality of evidence to suggest dysphagia assessment in stroke patients having been identified at being at risk of PSD. We found low to moderate quality of evidence for a variety of treatment options to improve swallowing physiology and swallowing safety. These options include dietary interventions, behavioural swallowing treatment including acupuncture, nutritional interventions, oral health care, different pharmacological agents and different types of neurostimulation treatment. Some of the studied interventions also had an impact on other clinical endpoints such as feedings status or pneumonia. Overall, further randomized trials are needed to improve the quality of evidence for the treatment of PSD.

Stroke and Pneumonia: Mechanisms, Risk Factors, Management, and Prevention

A stroke is a cerebrovascular medical emergency characterized by the sudden loss of neurological function due to interruption to the blood supply. A serious and common complication of stroke is pneumonia. This review article outlined various studies in order to understand the pathogenesis pathways that lead to the development of stroke-associated pneumonia, as well as therapeutic and preventive options to reduce pneumonia. The article looked for risk factors that increase the risk of developing pneumonia among stroke patients. In addition, it has reviewed various therapeutic modalities, such as postural modifications, pharmacological treatment, and other unique treatments, in an attempt to find which of them are efficient to decrease the occurrence of pneumonia and which of them are not. The article also attempts to emphasize the importance of early screening for dysphagia among stroke patients and demonstrates the importance of preventive strategies that can be easily implemented, such as routine oral care and behavioral modifications.

Original Research: Oral Care as Prevention for Nonventilator Hospital-Acquired Pneumonia: A Four-Unit Cluster Randomized Study

BACKGROUND

Nonventilator hospital-acquired pneumonia (NV-HAP) presents a serious and largely preventable threat to patient safety in U.S. hospitals. There is an emerging body of evidence on the effectiveness of oral care in preventing NV-HAP.

PURPOSE

The primary aim of this study was to determine the effectiveness of a universal, standardized oral care protocol in preventing NV-HAP in the acute care setting. The primary outcome measure was NV-HAP incidence per 1,000 patient-days.

METHODS

This 12-month study was conducted on four units at an 800-bed tertiary medical center. Patients on one medical and one surgical unit were randomly assigned to receive enhanced oral care (intervention units); patients on another medical and another surgical unit received usual oral care (control units).

RESULTS

Total enrollment was 8,709. For the medical control versus intervention units, oral care frequency increased from a mean of 0.95 to 2.25 times per day, and there was a significant 85% reduction in the NV-HAP incidence rate. The odds of developing NV-HAP were 7.1 times higher on the medical control versus intervention units, a significant finding. For the surgical control versus intervention units, oral care frequency increased from a mean of 1.18 to 2.02 times per day, with a 56% reduction in the NV-HAP incidence rate. The odds of developing NV-HAP were 1.6 times higher on the surgical control versus intervention units, although this result did not reach significance.

CONCLUSIONS

These findings add to the growing body of evidence that daily oral care as a means of primary source control may have a role in NV-HAP prevention. The implementation of effective strategies to ensure that such care is consistently provided warrants further study. It's not yet known what degree and frequency of oral care are required to effect favorable changes in the oral microbiome during acute care hospitalization.

Diagnosis and treatment of neurogenic dysphagia - S1 guideline of the German Society of Neurology

Introduction

Neurogenic dysphagia defines swallowing disorders caused by diseases of the central and peripheral nervous system, neuromuscular transmission, or muscles. Neurogenic dysphagia is one of the most common and at the same time most dangerous symptoms of many neurological diseases. Its most important sequelae include aspiration pneumonia, malnutrition and dehydration, and affected patients more often require long-term care and are exposed to an increased mortality. Based on a systematic pubmed research of related original papers, review articles, international guidelines and surveys about the diagnostics and treatment of neurogenic dysphagia, a consensus process was initiated, which included dysphagia experts from 27 medical societies.

Recommendations

This guideline consists of 53 recommendations covering in its first part the whole diagnostic spectrum from the dysphagia specific medical history, initial dysphagia screening and clinical assessment, to more refined instrumental procedures, such as flexible endoscopic evaluation of swallowing, the videofluoroscopic swallowing study and high-resolution manometry. In addition, specific clinical scenarios are captured, among others the management of patients with nasogastric and tracheotomy tubes. The second part of this guideline is dedicated to the treatment of neurogenic dysphagia. Apart from dietary interventions and behavioral swallowing treatment, interventions to improve oral hygiene, pharmacological treatment options, different modalities of neurostimulation as well as minimally invasive and surgical therapies are dealt with.

Conclusions

The diagnosis and treatment of neurogenic dysphagia is challenging and requires a joined effort of different medical professions. While the evidence supporting the implementation of dysphagia screening is rather convincing, further trials are needed to improve the quality of evidence for more refined methods of dysphagia diagnostics and, in particular, the different treatment options of neurogenic dysphagia. The present article is an abridged and translated version of the guideline recently published online (https://www.awmf.org/uploads/tx_szleitlinien/030-111l_Neurogene-Dysphagie_2020-05.pdf).

Structural Equation Modeling of Tongue Function and Tongue Hygiene in Acute Stroke Patients

In acute stroke patients, it is important to maintain tongue hygiene and tongue function for prognosis management. However, the direct relationship between these factors is unclear, since these are often assessed by multiple observables. In this study, we used structural equation modeling (SEM) analysis, a tool to analyze the relationship between concepts that cannot be measured directly, to analyze the relationship between tongue hygiene and tongue function. The subjects were 73 patients with acute stroke admitted to a university hospital who underwent dental intervention. Age, sex, nutritional intake method, clinical severity classification of dysphagia, number of current teeth, number of functional teeth, oral health, tongue movement, tongue coating, number of microorganisms on the tongue surface, tongue surface moisture level, and tongue pressure were measured at the first visit. SEM analysis showed that the relationship between tongue function and tongue hygiene was 0.05 between tongue function and swallowing function was 0.90, and that between tongue hygiene and swallowing function was 0.09. We found no statistical relationship between tongue function and tongue hygiene in acute stroke patients. However, it was reconfirmed that tongue function is strongly related to feeding and swallowing functions.

Aspiration Risk Factors, Microbiology, and Empiric Antibiotics for Patients Hospitalized With Community-Acquired Pneumonia

BACKGROUND

Aspiration community-acquired pneumonia (ACAP) and community-acquired pneumonia (CAP) in patients with aspiration risk factors (AspRFs) are infections associated with anaerobes, but limited evidence suggests their pathogenic role.

RESEARCH QUESTION

What are the aspiration risk factors, microbiology patterns, and empiric anti-anaerobic use in patients hospitalized with CAP?

STUDY DESIGN AND METHODS

This is a secondary analysis of GLIMP, an international, multicenter, point-prevalence study of adults hospitalized with CAP. Patients were stratified into three groups: (1) ACAP, (2) CAP/AspRF+ (CAP with AspRF), and (3) CAP/AspRF- (CAP without AspRF). Data on demographics, comorbidities, microbiological results, and anti-anaerobic antibiotics were analyzed in all groups. Patients were further stratified in severe and nonsevere CAP groups.

RESULTS

We enrolled 2,606 patients with CAP, of which 193 (7.4%) had ACAP. Risk factors independently associated with ACAP were male, bedridden, underweight, a nursing home resident, and having a history of stroke, dementia, mental illness, and enteral tube feeding. Among non-ACAP patients, 1,709 (70.8%) had CAP/AspRF+ and 704 (29.2%) had CAP/AspRF-. Microbiology patterns including anaerobes were similar between CAP/AspRF-, CAP/AspRF+ and ACAP (0.0% vs 1.03% vs 1.64%). Patients with severe ACAP had higher rates of total gram-negative bacteria (64.3% vs 44.3% vs 33.3%, P = .021) and lower rates of total gram-positive bacteria (7.1% vs 38.1% vs 50.0%, P < .001) when compared with patients with severe CAP/AspRF+ and severe CAP/AspRF-, respectively. Most patients (>50% in all groups) independent of AspRFs or ACAP received specific or broad-spectrum anti-anaerobic coverage antibiotics.

INTERPRETATION

Hospitalized patients with ACAP or CAP/AspRF+ had similar anaerobic flora compared with patients without aspiration risk factors. Gram-negative bacteria were more prevalent in patients with severe ACAP. Despite having similar microbiological flora between groups, a large proportion of CAP patients received anti-anaerobic antibiotic coverage.