High-Level PM2.5/PM10 Exposure Is Associated With Alterations in the Human Pharyngeal Microbiota Composition

Previous studies showed that high concentration of particulate matter (PM) 2.5 and PM10 carried a large number of bacterial and archaeal species, including pathogens and opportunistic pathogens. In this study, pharyngeal swabs from 83 subjects working in an open air farmer’s market were sampled before and after exposure to smog with PM2.5 and PM10 levels up to 200 and 300 μg/m3, respectively. Their microbiota were investigated using high-throughput sequencing targeting the V3–V4 regions of the 16S rRNA gene. The genus level phylotypes was increased from 649 to 767 in the post-smog pharyngeal microbiota, of which 142 were new and detected only in the post-smog microbiota. The 142 new genera were traced to sources such as soil, marine, feces, sewage sludge, freshwater, hot springs, and saline lakes. The abundance of the genera Streptococcus, Haemophilus, Moraxella, and Staphylococcus increased in the post-smog pharyngeal microbiota. All six alpha diversity indices and principal component analysis showed that the taxonomic composition of the post-smog pharyngeal microbiota was significantly different to that of the pre-smog pharyngeal microbiota. Redundancy analysis showed that the influences of PM2.5/PM10 exposure and smoking on the taxonomic composition of the pharyngeal microbiota were statistically significant (p < 0.001). Two days of exposure to high concentrations of PM2.5/PM10 changed the pharyngeal microbiota profiles, which may lead to an increase in respiratory diseases. Wearing masks could reduce the effect of high-level PM2.5/PM10 exposure on the pharyngeal microbiota

Incidence, temporal trend and factors associated with ventilator-associated pneumonia in mainland China: a systematic review and meta-analysis

Abstract Background Data to date is far from sufficient to describe the recent epidemiology of ventilator-associated pneumonia (VAP) in mainland China. This study aimed to estimate the overall incidence of VAP, with a special focus on its temporal trend and associated factors. Methods Meta-analyses of 195 studies published from 2010 to 2015 were conducted, followed by subgroup analyses by methodological quality, pre-defined setting characteristics and attributes of populations. Results The overall cumulative VAP incidence in mainland China was 23.8% (95% confidence interval (CI) 20.6–27.2%), with the results showing high heterogeneity. The pooled incidence densities were 24.14 (95% CI 21.19–27.51) episodes and 22.83 (95% CI 19.88–26.23) patients per 1000 ventilator-days. A decline in the cumulative incidence was observed from 2006 (49.5%, 95% CI 40.0–59.0%) to 2014 (19.6%, 95% CI 10.4–31.0%); differences in the incidence rates were also documented according to Chinese provinces and diagnostic criteria (p < 0.001). Older age (≥60 years), coma, re-intubation, tracheotomy and prolonged ventilation were the factors significantly associated with the occurrence of VAP. Conclusions The incidence of VAP remains high in mainland China but has decreased since 2006. The reported rates vary considerably across individual studies, probably due to variations in diagnosis and geographical region. More studies using standard definitions and cut-off points are needed to better clarify the epidemiology of VAP across the country

Association of insulin resistance with intra- and extra-cranial atherosclerotic burden in the nondiabetic community population

Aims: Few population-based studies have investigated the association between insulin resistance and atherosclerotic burden in intra- and extra-cranial arteries. The purpose of this study is to explore the relationship between insulin resistance and intra- and extra-cranial atherosclerotic burden in community-based nondiabetic participants. Methods: This is a cross-sectional analysis from a population-based prospective cohort-PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study in China. The homeostasis model assessment of insulin resistance (HOMA-IR) and insulin sensitivity indices (ISI0–120) were stratified by the quartiles, respectively. The atherosclerotic presence of plaques and burden was evaluated by high-resolution MRI. Binary or ordinal logistic regression was performed to assess the association between HOMA-IR or ISI0–120 and the presence and burden of atherosclerosis. Results: Among the 2754 participants, the mean age was 60.9 ± 6.6 years, and 1296 (47.1%) were males. Compared with the lowest quartile of HOMR-IR, the highest quartile of HOMA-IR (indicating a higher level of insulin resistance) was associated with an increased presence of plaques (OR:1.54, 95% CI:1.14–2.08), and atherosclerotic burden (OR:1.53, 95%CI:1.14–2.07) in intracranial arteries. Meanwhile, we observed a similar relationship between HOMA-IR and the presence or burden in extracranial atherosclerosis. The first (indicating a higher level of insulin resistance) quartiles of ISI0–120 were associated with the intracranial plaques (Q1, OR:1.56, 95%CI:1.16–2.11) and atherosclerotic burden (Q1, OR:1.57, 95%CI:1.17–2.12), but not extracranial plaques or atherosclerotic burden, compared with the fourth quartile of ISI0–120. Conclusions: Insulin resistance was associated with an increased intra-and extra-cranial atherosclerotic burden in the nondiabetic elderly Chinese population

Residual Risk of Trimethylamine‐N‐Oxide and Choline for Stroke Recurrence in Patients With Intensive Secondary Therapy

Background Trimethylamine N‐oxide (TMAO) contributes to cardiovascular disease through its prothrombotic, proatherothrombotic, and proinflammatory effects. We aimed to evaluate whether residual risk of recurrent stroke of TMAO and its precursor choline remain among patients who received dual‐antiplatelet therapy and intensive lipid‐lowering therapy and with a low inflammation level (high‐sensitivity C‐reactive protein <2 mg/L on admission). Methods and Results Patients with ischemic stroke or transient ischemic attack were enrolled from the CNSR‐III (Third China National Stroke Registry) in China. Plasma TMAO and choline concentrations at baseline were measured in 9793 participants using liquid chromatography–mass spectrometry. The primary outcome was a new stroke within 1 year. Multivariable‐adjusted hazard ratios were calculated using Cox regression models to investigate the associations of TMAO and choline with stroke recurrence. Among all patients, elevated TMAO and choline levels were associated with an increased risk of recurrent stroke (adjusted hazard ratios, 1.28 [95% CI, 1.12–1.45]; and 1.50 [95% CI, 1.32–1.71], respectively). Moreover, elevated TMAO and choline levels were associated with an increased risk of recurrent stroke among patients who received dual‐antiplatelet therapy (1.65 [95% CI, 1.28–2.13]; and 1.70 [95% CI, 1.32–2.19], respectively), intensive lipid‐lowering therapy (1.49 [95% CI, 1.15–1.94]; and 1.49 [95% CI, 1.15–1.92], respectively), with high‐sensitivity C‐reactive protein <2 mg/L (1.39 [95% CI, 1.14–1.69]; and 1.88 [95% CI, 1.53–2.30], respectively), and concurrently received dual‐antiplatelet therapy, intensive lipid‐lowering therapy and with high‐sensitivity C‐reactive protein <2 mg/L (3.57 [95% CI, 1.73–7.38]; and 2.19 [95% CI, 1.16–4.16], respectively). Conclusions TMAO and choline were risk factors for recurrent stroke independent of dual‐antiplatelet therapy, intensive lipid‐lowering therapy at discharge, and low inflammation on admission

Additional file 1: of Incidence, temporal trend and factors associated with ventilator-associated pneumonia in mainland China: a systematic review and meta-analysis

Table S1. Search strategies and results. Table S2. List of all the included studies. Table S3. General information of all the included studies. Table S4. The results of subgroup analyses by Chinese provinces and years of study. Table S5. Summary of diagnostic requirements for the three published sets of criteria in mainland China. Figure S1. Forest plot of the cumulative incidence of ventilator-associated pneumonia using a random-effects model. Figure S2. Forest plot of the incidence density (reported as episodes per 1000 ventilator-days) of ventilator-associated pneumonia using a random-effects model. Figure S3. Forest plot of the incidence density (reported as patients per 1000 ventilator-days) of ventilator-associated pneumonia using a random-effects model. (PDF 2137 kb

Blood Pressure Partially Mediated the Association of Insulin Resistance and Cerebral Small Vessel Disease: A Community‐Based Study

Background Insulin resistance as a significant vascular risk factor has been studied in relation to cerebral small vessel disease (SVD). Evidence suggests that insulin resistance might trigger high blood pressure (BP). Therefore, we aimed to investigate whether insulin resistance impacts SVD with a mediating effect of BP in nondiabetic subjects. Methods and Results PRECISE (Polyvascular Evaluation for Cognitive Impairment and Vascular Events) study participants underwent brain and vascular imaging techniques and metabolomic risk factors measurements. Insulin resistance was evaluated by the insulin sensitivity index and the Homeostatic Model Assessment for Insulin Resistance based on the standard oral glucose tolerance test. On average, 2752 nondiabetic subjects (47.1% men) aged 60.9 years were included. The multivariable logistic regression model and linear regression model tested the association of insulin resistance with BP components (including systolic BP [SBP], diastolic BP (DBP), and pulse pressure [PP]) and SVD, and of BP components with SVD. In the mediation analysis, SBP, DBP, and PP were found to partially mediate the detrimental effect of insulin resistance (assessed by the insulin sensitivity index) on lacunes (mediation percentage: SBP, 31.15%; DBP, 34.21%; PP, 10.43%), white matter hyperintensity (mediation percentage: SBP, 37.34%; DBP, 44.15%; PP, 9.80%), and SVD total burden (mediation percentage: SBP, 42.07%; DBP, 49.29%; PP, 11.71%) (all P<0.05). The mediation analysis results were not significant when using the Homeostatic Model Assessment for Insulin Resistance to assess insulin resistance. Conclusions Higher insulin resistance was associated with SVD in this community‐dwelling population. The association of insulin resistance with lacunes, white matter hyperintensity, and SVD total burden was explained in part by BP. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03178448

Differential associations of lipoprotein(a) level with cerebral large artery and small vessel diseases

Background and purpose Cerebral large artery and small vessel diseases are related to different pathogenetic mechanisms and have different risk factor profile. Lipoprotein(a) (Lp(a)) was shown to promote atherosclerosis but data was limited on its association with cerebral small vessel diseases (cSVD). The objective of this study was to assess the associations of Lp(a) level with the two types of cerebrovascular diseases.Methods Community-dwelling subjects aged 50–75 years from the baseline survey of The PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events study were included. Lp(a) concentrations was measured and categorised into three groups according to the tertiles. Eligible participants were scanned by a 3.0T MRI scanner and assessed for intracranial atherosclerosis and cSVD burden based on four imaging markers.Results This study included 3059 subjects. The average age of the participants was 61.2±6.7 years, and 53.5% (1636) were female. Compared with the first tertile, subjects with the second and third tertiles of Lp(a) concentrations were associated with an increased odds of presence of intracranial plaque (18.7% vs 15.4%, adj.OR 1.37, 95% CI 1.08 to 1.75; 18.9% vs 15.4%, adj.OR 1.34, 95% CI 1.05 to 1.72). Similar associations were observed for intracranial atherosclerotic burden. Whereas, subjects with the third tertile of Lp(a) level had a decreased odds of presence of cSVD (25.9% vs 31.7%, adj.OR 0.74, 95% CI 0.60 to 0.92) and lower cSVD burden (adj.cOR 0.76, 95% CI 0.62 to 0.94).Conclusions In this study, Lp(a) concentrations were positively associated with presence and burden of intracranial atherosclerosis, but was inversely associated with cSVD.Trial registration number NCT03178448

Impaired glymphatic system as evidenced by low diffusivity along perivascular spaces is associated with cerebral small vessel disease: a population-based study

Objective This study aims to investigate the associations of glymphatic system with the presence, severity and neuroimaging phenotypes of cerebral small vessel disease (CSVD) in a community-based population.Method This report included 2219 community-dwelling people aged 50–75 years who participated in the PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events cohort. The diffusivity along perivascular spaces based on diffusion tensor imaging (DTI-ALPS index) was measured to assess glymphatic pathway. The presence and severity of CSVD were estimated using a CSVD score (points from 0 to 4) and a modified CSVD score (points from 0 to 4), which were driven by 4 neuroimaging features of CSVD, including white matter hyperintensity (WMH), enlarged perivascular spaces (EPVS), lacunes, cerebral microbleeds. Brain atrophy (BA) was also evaluated. Binary or ordinal logistic regression analyses were carried out to investigate the relationships of DTI-ALPS index with CSVD.Result The mean age was 61.3 (SD 6.6) years, and 1019 (45.9%) participants were men. The average DTI-ALPS index was 1.67±0.14. Individuals in the first quartile (Q1) of the DTI-ALPS index had higher risks of the presence of CSVD (OR 1.77, 95% CI 1.33 to 2.35, p&lt;0.001), modified presence of CSVD (odds ratio (OR) 1.80, 95% CI 1.38 to 2.34, p&lt;0.001), total burden of CSVD (common OR (cOR) 1.89, 95% CI 1.43 to 2.49, p&lt;0.001) and modified total burden of CSVD (cOR 1.95, 95% CI 1.51 to 2.50, p&lt;0.001) compared with those in the fourth quartile (Q4). Additionally, individuals in Q1 of the DTI-ALPS index had increased risks of WMH burden, modified WMH burden, lacunes, basal ganglia-EPVS and BA (all p&lt;0.05).Conclusion A lower DTI-ALPS index underlay the presence, severity and typical neuroimaging markers of CSVD, implying that glymphatic impairment may interact with CSVD-related pathology in the general ageing population.Trial registration number NCT03178448