Association Between Gut Microbiota and Delirium in Acutely Ill Older Adults.

Our aim was to investigate the association between gut microbiota and delirium occurrence in acutely ill older adults. We included 133 participants 65+ years consecutively admitted to the emergency department of a tertiary university hospital, between September 2019 and March 2020. We excluded candidates with ≥24-hour antibiotic utilization on admission, recent prebiotic or probiotic utilization, artificial nutrition, acute gastrointestinal disorders, severe traumatic brain injury, recent hospitalization, institutionalization, expected discharge ≤48 hours, or admission for end-of-life care. A trained research team followed a standardized interview protocol to collect sociodemographic, clinical, and laboratory data on admission and throughout the hospital stay. Our exposure measures were gut microbiota alpha and beta diversities, taxa relative abundance, and core microbiome. Our primary outcome was delirium, assessed twice daily using the Confusion Assessment Method. Delirium was detected in 38 participants (29%). We analyzed 257 swab samples. After adjusting for potential confounders, we observed that a greater alpha diversity (higher abundance and richness of microorganisms) was associated with a lower risk of delirium, as measured by the Shannon (odds ratio [OR] = 0.77; 95% confidence interval [CI] = 0.60-0.99; p = .042) and Pielou indexes (OR = 0.69; 95% CI = 0.51-0.87; p = .005). Bacterial taxa associated with pro-inflammatory pathways (Enterobacteriaceae) and modulation of relevant neurotransmitters (Serratia: dopamine; Bacteroides, Parabacteroides: GABA) were more common in participants with delirium. Gut microbiota diversity and composition were significantly different in acutely ill hospitalized older adults who experienced delirium. Our work is an original proof-of-concept investigation that lays a foundation for future biomarker studies and potential therapeutic targets for delirium prevention and treatment.

Community-acquired pneumonia severity assessment tools in patients hospitalized with COVID-19: a validation and clinical applicability study.

OBJECTIVE: To externally validate community-acquired pneumonia (CAP) tools on patients hospitalized with coronavirus disease 2019 (COVID-19) pneumonia from two distinct countries, and compare their performance with recently developed COVID-19 mortality risk stratification tools. METHODS: We evaluated 11 risk stratification scores in a binational retrospective cohort of patients hospitalized with COVID-19 pneumonia in São Paulo and Barcelona: Pneumonia Severity Index (PSI), CURB, CURB-65, qSOFA, Infectious Disease Society of America and American Thoracic Society Minor Criteria, REA-ICU, SCAP, SMART-COP, CALL, COVID GRAM and 4C. The primary and secondary outcomes were 30-day in-hospital mortality and 7-day intensive care unit (ICU) admission, respectively. We compared their predictive performance using the area under the receiver operating characteristics curve (AUC), sensitivity, specificity, likelihood ratios, calibration plots and decision curve analysis. RESULTS: Of 1363 patients, the mean (SD) age was 61 (16) years. The 30-day in-hospital mortality rate was 24.6% (228/925) in São Paulo and 21.0% (92/438) in Barcelona. For in-hospital mortality, we found higher AUCs for PSI (0.79, 95% CI 0.77-0.82), 4C (0.78, 95% CI 0.75-0.81), COVID GRAM (0.77, 95% CI 0.75-0.80) and CURB-65 (0.74, 95% CI 0.72-0.77). Results were similar for both countries. For the 1%-20% threshold range in decision curve analysis, PSI would avoid a higher number of unnecessary interventions, followed by the 4C score. All scores had poor performance (AUC <0.65) for 7-day ICU admission. CONCLUSIONS: Recent clinical COVID-19 assessment scores had comparable performance to standard pneumonia prognostic tools. Because it is expected that new scores outperform older ones during development, external validation studies are needed before recommending their use.

Anesthetics, cerebral protection and preconditioning.

BACKGROUND AND OBJECTIVES: Several studies demonstrate that cerebral preconditioning is a protective mechanism against a stressful situation. Preconditioning determinants are described, as well as the neuroprotection provided by anesthetic and non-anesthetics agents. CONTENT: Review based on the main articles addressing the pathophysiology of ischemia-reperfusion and neuronal injury and pharmacological and non-pharmacological factors (inflammation, glycemia, and temperature) related to the change in response to ischemia-reperfusion, in addition to neuroprotection induced by anesthetic use. CONCLUSIONS: The brain has the ability to protect itself against ischemia when stimulated. The elucidation of this mechanism enables the application of preconditioning inducing substances (some anesthetics), other drugs, and non-pharmacological measures, such as hypothermia, aimed at inducing tolerance to ischemic lesions.