Toxicity of particulate emissions from residential biomass combustion: An overview of in vitro studies using cell models

This article aims to critically review the current state of knowledge on in vitro toxicological assessments of particulate emissions from residential biomass heating systems. The review covers various aspects of particulate matter (PM) toxicity, including oxidative stress, inflammation, genotoxicity, and cytotoxicity, all of which have important implications for understanding the development of diseases. Studies in this field have highlighted the different mechanisms that biomass combustion particles activate, which vary depending on the combustion appliances and fuels. In general, particles from conventional combustion appliances are more potent in inducing cytotoxicity, DNA damage, inflammatory responses, and oxidative stress than those from modern appliances. The sensitivity of different cell lines to the toxic effects of biomass combustion particles is also influenced by cell type and culture conditions. One of the main challenges in this field is the considerable variation in sampling strategies, sample processing, experimental conditions, assays, and extraction techniques used in biomass burning PM studies. Advanced culture systems, such as co-cultures and air-liquid interface exposures, can provide more accurate insights into the effects of biomass combustion particles compared to simpler submerged monocultures. This review provides critical insights into the complex field of toxicity from residential biomass combustion emissions, underscoring the importance of continued research and standardisation of methodologies to better understand the associated health hazards and to inform targeted interventions.

The role of snow in scavenging aerosol particles: A physical-chemical characterization

The below cloud scavenging of aerosols by snow has been analysed in León (NW Spain). Six snow events were registered over the course of one year of study. Ultrafine and accumulation aerosol particles were measured using a scanning mobility particle sizer spectrometer, while hydrometeors were characterized using a disdrometer. Furthermore, the chemical composition of the melted snow-water samples (soluble and insoluble fractions) was analysed. The scavenging coefficient (λ) showed a great variability among events. An effective washing of particles was observed during the first 30 min of snowfall. The mean change in the scavenging efficiency (%ΔC) of particle number concentration (PNC) and λ coefficient during this time interval were: i) nucleation mode: 36.3 % and 3.02 · 10-4 s-1; ii) Aitken mode: 30.4 % and 2.37 · 10-4 s-1 and iii) accumulation mode: 22.4 % and 1.77 · 10-4 s-1. The range of particle sizes that is less efficiently scavenged by snowfall was observed between 400 and 600 nm. When analyzing the whole snow event, an increase of PNC was observed. Two possible explanations underlie this behaviour: it could be caused by changes in air masses or by the resuspension of aerosol particles scavenged by snowflakes upon reaching the ground. A clear relationship was observed between Ca2+, SO42- and NO3- concentrations of aerosol particles before the snow event and the concentrations registered in the melted snow-water. The largest and smallest changes in aerosol number concentrations were caused by snowflakes of 3 and 6 mm in diameter, respectively. The particle size distributions (PSD) were fitted to log-normal distributions and the parameters were compared before and after snowfall.

Thiopurines have no impact on outcomes of Crohn's disease patients beyond 12 months of maintenance treatment with infliximab

BACKGROUND

The emergence of new treatments the inflammatory bowel diseases (IBD) raised questions regarding the role of older agents, namely thiopurines.

AIMS

To clarify the benefits of combination treatment with thiopurines on Crohn's disease (CD) patients in the maintenance phase of infliximab.

METHODS

In this analysis of the 2-year prospective multicentric DIRECT study, patients were assessed in terms of clinical activity, faecal calprotectin (FC), C-reactive protein (CRP), and infliximab pharmacokinetics. A composite outcome based on clinical- and drug-related items was used to define treatment failure.

RESULTS

The study included 172 patients; of these, 35.5 % were treated with combination treatment. Overall, 18 % of patients achieved the composite outcome, without statistically significant differences between patients on monotherapy and on combination treatment (21.6% vs 11.5 %, p = 0.098). Median CRP, FC, and infliximab pharmacokinetic parameters were similar in both groups. However, in the sub-analysis by infliximab treatment duration, in patients treated for less than 12 months, the composite outcome was reached in fewer patients in the combination group than in the monotherapy group (7.1% vs 47.1 %, p = 0.021).

CONCLUSION

In CD patients in maintenance treatment with infliximab, combination treatment does not seem to have benefits over infliximab monotherapy beyond 12 months of treatment duration.

Residential combustion of coal: Effect of the fuel and combustion stage on emissions

Worldwide coal is still used for household heating purposes not only because it is available and cheap but also due to behavioural issues. Regional variability in fuels and combustion appliances make accurate emission estimates from this source hard to achieve. In the present study, gaseous (CO, VOCs, SO2 and NOX) and particulate matter (TSP) emission factors (EFs) were determined for Spanish household coal combustion covering three commercial coals and distinct combustion stages and mimicking usage patterns in real households. TSP samples were analysed to determine water-soluble inorganic ions, metal(loid)s, and organic and elemental carbon (OC and EC). Additionally, the morphology of the emitted particles was also characterised. CO (3.43-169 g kg-1), NOX (1.29-6.00 g kg-1) and SO2 (8.96-22.3 g kg-1) EFs showed no trend regarding the combustion stage or coal type tested. On the other hand, VOC, TSP and EC EFs were higher for the ignition/devolatilisation combustion stage, regardless of the fuel tested. TSP EFs (0.085-1.08 g kg-1) increased with increasing coal volatile matter while the opposite trend was recorded for VOC emissions (0.045-3.39 gC kg-1). TSP carbonaceous matter was dominated by EC while OC represented a small fraction of the particulate mass emitted (less than 8 %wt.). Inorganic compounds composed an important fraction of the TSP samples. Sulphate particulate mass fractions (8.66-22.9 %wt.) appeared to increase with coal S-content. Coal combustion released particles with diverse morphologies, including silicate-rich particles, ferro- and glassy-spheres. This study provides novel emission factors to update emission inventories of residential coal combustion. Additionally, detailed chemical profiles were obtained for source apportionment.

Has the therapeutical ceiling been reached in Crohn's disease randomized controlled trials? A systematic review and meta-analysis

BACKGROUND AND AIMS

The availability of biological agents for inflammatory bowel disease has increased over the past years. In this systematic review and meta-analysis, we aimed to explore time trends in clinical response and clinical remission rates in Crohn's disease (CD) patients treated with biologics while discussing the need for new strategies.

METHODS

MEDLINE, Cochrane, and ISI Web of Science databases were searched for randomized placebo-controlled trials with biological agents in moderate-to-severe CD patients. Sub-group and meta-regression analyses compared treatment and placebo by calculating the pooled odds ratios of clinical remission and clinical response, across time categories and publication year. We also estimated the proportion of patients achieving clinical remission and clinical response by comparing both groups according to the publication year.

RESULTS

Twenty-five trials were included in the systematic review, which enrolled 8879 patients between 1997 and 2022. The clinical remission and clinical response odds, in induction and maintenance, have been constant over time, as no statistically significant differences were found between time categories (interaction p-values: clinical remission [induction, p = 0.19; maintenance, p = 0.24]; clinical response [induction, p = 0.43; maintenance, p = 0.59]). In meta-regression analyses, publication year did not influence these outcomes (clinical remission [induction, OR 1.01{95% CI 0.97-1.05}, p = 0.72; clinical response [induction, OR 1.01{95% CI 0.97-1.04]; p = 0.63; maintenance, OR 1.03{95% CI 0.98-1.07}; p = 0.21]), with the exception of clinical remission in maintenance studies, which presented a decreased effect (odds ratio 0.97{95% CI 0.94-1.00}, p = 0.03]).

CONCLUSIONS

Our review highlights that the odds of clinical outcomes in CD patients receiving biological treatment relative to placebo have been stable in the last decades.

A service evaluation of joint working across sectors to promote self-administration of subcutaneous systemic anti-cancer therapy in breast cancer patients

Introduction

Trastuzumab(T) is a humanized monoclonal antibody used in the treatment of HER2-positive breast cancer and is available as a subcutaneous(sc) formulation thereby allowing short and convenient administration. A lack of trained nurses to administer T at home and/or train patients at home to self-administer, together with challenges in maintaining cold-chain delivery have impeded uptake of home administration.1,2 In order to support patients’ ability to self-administer T at home, we have implemented an educational programme that includes nurse-led training, education material, support apps and follow-up telephone clinics. Home delivery of pre-filled syringes was enabled in collaboration with commercial providers for aseptics and logistic.

Aim

The aim of this service evaluation was to evaluate the utility of this programme from the patients’ perspective and to assess patient satisfaction and impact on quality of life (QOL).

Methods

A previously validated Self-Injection Assessment Questionnaire (SIAQ)3 was modified to assess patient satisfaction, perceptions and impact of the programme. Patients who had agreed to enrol on the ‘self-administration’ scheme, were asked to complete the questionnaire at baseline, at the third training session and at the second self-administered dose. Approval from a Research Ethics Committee is not required for this service evaluation.

Results

All 14 patients offered the questionnaire responded to all questions. The median age was 58 years old (age range 43-76), 11 patients were Caucasian, 2 were Asian and one was African/Caribbean. The average distance from their home address to hospital was 10.1 miles (range 4-19). Following completion of the one-to-one nurse training there was an improvement in patient confidence to self-administer sc. T. No differences in ‘feeling in control of their treatment’ or ‘satisfaction of attending hospital appointments’ were noted. Of the 11 patients who reached the self-administration stage, 10 reported that they felt ‘very confident’ and 8 reported that it was ‘very easy’ to give themselves the injection. All patients rated themselves ‘very satisfied’ with self-administration and reported that the nurse training programme helped them to be more confident. 10 patients reported that the App and written information was useful as well as the pre- and post- administration telephone clinics. All patients reported that the self-administration programme had a positive impact on their QOL by reducing the number of hospital visits. In the first 4 months of self-administration each patient reduced their hospital attendance by an average of 8 appointments (median=8) equating to 10 hours of time that would have been spent at hospital.

Discussion/Conclusion

The subcutaneous T self-administration programme was well received by patients. The nurse training sessions and supportive materials enabled patients to feel more confident about self-administration with no reported incidents or adverse events. This led to fewer hospital visits and improved QOL. This programme was critically dependent on the services of a commercial compounder and homecare provider, emphasizing the importance of joint working between the NHS and commercial sector. Evaluation of this programme will continue and will include other agents, including Phesgo® (sc trastuzumab and pertuzumab) which have more patients and will improve the reliability of the results.

References

1. Tjalma, W., Huizing, M., Papadimitriou, K. The smooth and bumpy road of trastuzumab administration: from intravenous (IV) in a hospital to subcutaneous (SC) at home. Facts Views Vis Obgyn, 2017;9(1):51-55.

2. Grady, PA, Gough, LL. Self-management: a comprehensive approach to management of chronic conditions. American Journal of Public Health 2014; 104(8):e25-31. doi:10.2105/AJPH.2014.302041

3. Keininger D, Coteur G. Assessment of self-injection experience in patients with rheumatoid arthritis: psychometric validation of the Self-Injection Assessment Questionnaire (SIAQ). Health Qual Life Outcomes. 2011;9:2. doi:10.1186/1477-7525-9-2

Impact of Crohn's Disease Therapies on Histology in Randomized Controlled Trials: Systematic Review With Meta-analysis

BACKGROUND

The effectiveness of Crohn's disease treatments for inducing histological outcomes has not been addressed systematically. We performed a systematic review and meta-analysis of randomized controlled trials in Crohn's disease to assess the impact of therapies on mucosal histopathology.

METHODS

Databases (MEDLINE, CENTRAL, Web of Science, EMBASE) were searched for randomized controlled trials including adult patients and evaluating histological outcomes. Risk of bias was evaluated using the Critical Appraisal Skills Programme. Histological outcomes, pooled frequencies, pooled odds ratios, and standard mean differences of the histological scores were compared between the intervention and placebo groups using a random-effects model.

RESULTS

Out of 2070 records, 10 studies were included. The quality of the studies ranged from moderate to high, but they were clinically and methodologically diverse. All interventions were superior to placebo. Histological response was achieved by 68% of patients, and 38% achieved remission. Pooled odds ratio for histological remission in patients receiving intervention vs placebo was 4.14 (95% CI, 2.28-7.50; I2 0%; P < .01). Heterogeneity in histological response estimates was significant, and subgroup analysis of the odds ratio results was limited by the low number of studies per group. The standard mean difference of histological scores was higher for patients receiving intervention in both induction and maintenance studies (-2.95; 95% CI, -4.17 to -1.74; I2 83% P < .00; and -2.58; 95% CI, -3.89 to -1.27; I2 56% P < .00).

CONCLUSIONS

Crohn's disease therapies are effective for achieving histological outcomes. Adherence to recently published consensus on histopathology harmonization assessment in Crohn's disease would facilitate adequate comparison between studies in the future.

The Magnitude of Crohn's Disease Direct Costs in Health Care Systems (from Different Perspectives): A Systematic Review

BACKGROUND

The prevalence of inflammatory bowel disease (IBD) has been increasing worldwide, causing high impact on the quality of life of patients and an increasing burden for health care systems. In this systematic review, we reviewed the literature concerning the direct costs of Crohn's disease (CD) for health care systems from different perspectives: regional, economic, and temporal.

METHODS

We searched for original real-world studies examining direct medical health care costs in Crohn's disease. The primary outcome measure was the mean value per patient per year (PPY) of total direct health care costs for CD. Secondary outcomes comprised hospitalization, surgery, CD-related medication (including biologics), and biologics mean costs PPY.

RESULTS

A total of 19 articles were selected for inclusion in the systematic review. The studies enrolled 179 056 CD patients in the period between 1997 and 2016. The pooled mean total cost PPY was €6295.28 (95% CI, €4660.55-€8503.41). The pooled mean hospitalization cost PPY for CD patients was €2004.83 (95% CI, €1351.68-€2973.59). The major contributors for the total health expenditure were biologics (€5554.58) and medications (€3096.53), followed by hospitalization (€2004.83) and surgery (€1883.67). No differences were found between regional or economic perspectives, as confidence intervals overlapped. However, total costs were significantly higher after 2010.

CONCLUSIONS

Our review highlighted the burden of CD for health care systems from different perspectives (regional, economic, and temporal) and analyzed the impact of the change of IBD treatment paradigm on total costs. Reducing the overall burden can depend on the increase of remission rates to further decrease hospitalizations and surgeries.

Subclinical Persistent Inflammation as Risk Factor for Crohn's Disease Progression: Findings From a Prospective Real-World Study of 2 Years

BACKGROUND AND AIMS

Subclinical intestinal inflammation is common in Crohn's disease (CD). We aimed to explore its impact in the disease progression of infliximab-treated patients and the usefulness of fecal calprotectin (FC) and C-reactive protein (CRP) as surrogate minimally invasive biomarkers.

METHODS

The registry-based, prospective, observational, multicenter DIRECT (study to investigate the correlation of fecal calprotectin with serum Drug levels and development of an antI-dRug antibodiEs among adult patients with inflammatory bowel disease reCeiving anti-TNF-alfa treatment or vedoluzimab treatment) study followed infliximab-treated CD patients for 2 years in a tertiary care setting. Persistent inflammation definition was based on FC (>150 μg/g, >250 μg/g, or >350 μg/g) or serum CRP (>3 μg/mL) concentrations over 2 consecutive or at least 3 visits. Patients were categorized according to a composite outcome reflecting disease progression that incorporated surgery; hospitalizations; new fistulae, abscess, or stricture; and treatment escalation.

RESULTS

Of 322 DIRECT study patients, 180 asymptomatic, infliximab treated on maintenance regimen were included in the analysis. Patients developing the composite endpoint (n = 96) presented higher median levels of FC (205 [interquartile range, 98-515] μg/g; P = .045) but not of CRP (2.50 [interquartile range, 0.80-6.00] μg/mL; P = .895). Biomarker-defined persistent subclinical inflammation prevalence ranged from 24% to 81%. Considering FC >250 μg/g in 2 consecutive visits, prevalence was 50%, odds of achieving the endpoint were increased 3-fold (odds ratio, 2.996 [95% confidence interval, 1.557-5.776]), and time-to-outcome occurrence was significantly lower among subjects with persistent inflammation (median time: 11 months). Both clinical-related and treatment-related components were significantly associated with persistent inflammation. Definitions based on CRP >3 μg/mL, FC >150 μg/g, FC >350 μg/g, double biomarkers (FC >250 μg/g and/or CRP >3 μg/mL), or more visits did not improve predictive ability.

CONCLUSIONS

Persistent inflammation, defined simply and readily by FC >250 μg/g over 2 consecutive visits, was associated with a significantly higher risk and shorter time to occurrence of a composite outcome reflecting disease progression in asymptomatic infliximab-treated CD patients.

Children's exposure to size-fractioned particulate matter: Chemical composition and internal dose

The health effects of the particulate matter (PM) depend not only on its aerodynamic diameter (AD) and chemical composition, but also on the time activity pattern of the individuals and on their age. The main objective of this work was to assess the exposure of children to aerosol particles by using personal instruments, to study the particle size and composition of the inhaled PM, and to estimate their transport and deposition into the human respiratory tract (HRT). The average daily PM2.5 exposure was 19 μg/m³ and the size fractions with the greatest contribution to PM2.5 concentrations were 1 < AD <2.5 μm and AD <0.25 μm. Results indicated a contribution of 9% from the mineral aerosol, 7.2% from anthropogenic sulphate, 6.7% from black carbon and 5% from anthropogenic trace elements to the daily exposure to PM2.5. The levels of mineral and marine elements increased with increasing particle size, while anthropogenic elements were present in higher concentrations in the finest particles. Particle size has been shown to influence the variability of daily dose deposited between the extrathoracic and alveolar-interstitial zones. On average, 3% of the PM deposited in the bronchial region, whereas 5% to 8% were found in the bronchiolar region. The level of physical activity had a significant contribution to the total daily dose.

Composite outcomes in observational studies of Crohn's disease: a systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis aims to assess composite and aggregate outcomes of observational studies in Crohn's disease and to evaluate whether the number and type of variables included affect the frequency of the outcome.

METHODS

MEDLINE [via PubMed], Scopus and Web of Science were searched to identify observational studies that enrolled patients with Crohn's disease and evaluated a composite or aggregate outcome. The proportion of patients achieving the outcome was determined and a random-effects meta-analysis was performed to evaluate how the frequency of each outcome varies according to the reporting of predefined variables.

RESULTS

From 10,257 identified records, 46 were included in the qualitative analysis and 38 in the meta-analysis. The frequency for composite and aggregate outcomes was 0.445 [95% confidence interval (CI): 0.389-0.501] and 0.140 (95% CI: 0.000-0.211), respectively. When comparing composite outcomes by number of included variables, the frequency was 0.271 (95% CI: 0.000-0.405) and 0.698 (95% CI: 0.651-0.746), for one and six variables, respectively. The frequency of the composite outcome varied according to the identity of the variables being reported. Specific pairs of predefined variables had a significant effect in the frequency of composite outcomes.

CONCLUSION

Composite outcomes with increasing number of predefined variables show an increase in frequency. Outcomes including variables such as 'Surgery' and 'Steroids' had higher frequencies when compared with the ones that did not include these variables. These results show that the frequency of composite outcomes is dependent on the number and type of variables being reported.

Composite outcomes in observational studies of ulcerative colitis: A systematic review and meta-analysis

Background

Ulcerative colitis (UC) has been the focus of numerous observational studies over the years and a common strategy employed in their design is the use of composite and aggregate outcomes.

Objective

This systematic review and meta‐analysis aims to identify composite and aggregate outcomes of observational studies in UC and to evaluate how the number and type of variables included and the length of follow‐up affect the frequency of patients that achieve these outcomes.

Methods

A systematic literature search was carried out using MEDLINE [via PubMed], Scopus, and Web of Science online databases. Observational studies that included UC patients and reported composite or aggregate outcomes were identified. A set of variables considered to be representative of progressive or disabling UC was defined, the proportion of patients attaining the outcomes was determined and a random‐effects meta‐analysis was performed by dividing the identified studies into subgroups according to different criteria of interest.

Results

A total of 10,264 records were identified in the systematic search, of which 33 were retained for qualitative analysis and 20 were included in the meta‐analysis. The mean frequency for composite outcomes was 0.363 [95% confidence interval (CI) 0.323‐0.403]. The frequency of composite outcome for the subgroup of studies that included the variable “Biologics” was significantly higher than for those in which this variable was not reported [0.410; 95% CI 0.364‐0.457 versus 0.298; 95% CI 0.232‐0.364; p = 0.006]. Composite outcomes were also more frequent as the follow‐up duration increased.

Conclusion

The frequency of composite outcomes in observational studies of UC is dependent on the specific identity of the variables being reported. Moreover, longer follow‐up periods are associated with higher frequencies of composite outcomes. The evidence provided here is useful for the design of future observational studies of UC that aim to maximize the frequency of patients that achieve composite outcomes.

Summarize the established knowledge on this subject

Observational studies have become a valuable source of information but also present a remarkable heterogeneity.

The inconsistency on the reported outcomes between individual studies and the potential for reporting biases has led to calls for the development of core outcome sets (COS).

What are the significant and/or new findings of this study?

This is the first systematic review and meta‐analysis of outcomes in observational studies of Ulcerative colitis (UC).

The frequency of composite outcomes in observational studies of UC is dependent on the specific identity of the variables being reported and on the follow‐up duration.

Reporting of the variable “Biologics” significantly increased the frequency of composite outcomes.

These findings may be useful for the design of future observational studies of UC.

Histologic Features of Colon Biopsies (Geboes Score) Associated With Progression of Ulcerative Colitis for the First 36 Months After Biopsy

BACKGROUND & AIMS

In addition to findings from endoscopy, histologic features of colon biopsies have been associated with outcomes of patients with ulcerative colitis (UC). We investigated associations between Geboes scores (a system to quantify structural changes and inflammatory activity in colon biopsies) and UC progression, and the time period over which this association is valid.

METHODS

We analyzed data from 399 asymptomatic patients with UC enrolled in the ACERTIVE study, followed at 13 inflammatory bowel disease (IBD) centers in Portugal through 31 December 2019. Blood and stool samples were collected and analyzed, and all patients underwent sigmoidoscopy within 24 h of sample collection. We assessed baseline endoscopic status (Mayo endoscopic subscore), histologic features of 2 sigmoid and 2 rectal biopsies (Geboes score), and concentration of fecal calprotectin (FC). The primary outcome was UC progression (surgical, pharmacologic, and clinical events). We generated survival curves for 36 months or less and more than 36 months after biopsy according to Geboes score using the Kaplan-Meier method and compared findings with those from a log rank test. Cox regression was adjusted for Mayo endoscopic subscore, Geboes score, and level of FC; results were expressed as adjusted hazard ratios (HR) with 95% CIs.

RESULTS

Patients with Geboes scores >2B.0, Geboes scores >3.0, or Geboes scores >4.0 had a higher frequency of, and a shorter time to UC progression, than patients with Geboes scores ≤2B.0, Geboes scores ≤3.0, or Geboes score ≤4.0 (P < .001). Disease progression occurred earlier in patients with Geboes scores >2B.0, Geboes scores >3.0, or Geboes scores >4.0 compared with patients with Geboes scores ≤2B.0 (HR, 2.021; 95% CI, 1.158-3.526), Geboes scores ≤3.0 (HR, 2.007; 95% CI, 1.139-3.534), or Geboes scores ≤4.0 (HR, 2.349; 95% CI, 1.269-4.349), respectively, in the first 36 months after biopsy. Similar results were found for patients with concentrations of FC below 150 μg/g.

CONCLUSIONS

We found histologic features of colon biopsies (Geboes score) to be an independent risk factor for progression of UC in the first 36 months after biopsy.

Prevalence of SARS-CoV-2 Antibodies after First 6 Months of COVID-19 Pandemic, Portugal

In September 2020, we tested 13,398 persons in Portugal for antibodies against severe acute respiratory syndrome coronavirus 2 by using a quota sample stratified by age and population density. We found a seroprevalence of 2.2%, 3-4 times larger than the official number of cases at the end of the first wave of the pandemic.

AB0375 EXTERNAL VALIDATION OF THE GIANT CELL ARTERITIS PROBABILITY SCORE IN THE NETHERLANDS

Background:

Severe complications of giant cell arteritis (GCA), such as blindness and ischemic stroke, can be prevented by timely treatment. This requires early and accurate diagnosis. In 2019, Laskou et al. developed a clinical GCA probability score (GCAPS) that allows physicians to assess the probability of GCA at initial assessment. The GCAPS is suitable for easy implementation in daily practice. It has a high sensitivity (95.7%) and specificity (86.7%) at a cut-off value of 9.5 as proposed by Laskou et al.

Objectives:

The aim of this study was to externally validate the GCAPS in a general hospital.

Methods:

A retrospective cohort of patients with suspected GCA between January 1st 2017 and October 1st 2019 at Ziekenhuisgroep Twente (the Netherlands) was used. As the parameter extra-cranial artery abnormality was not available in our cohort, a modified version of the GCAPS was used (m-GCAPS). The m-GCAPS was compared to clinical diagnosis of a rheumatologist after six months in accordance with Laskou et al. The validity of the m-GCAPS was assessed by plotting a receiver operating characteristic (ROC) curve and assessing sensitivity and specificity for multiple cut-off values. For practical purposes, risk stratifications as proposed by Sebastian et al. (2020) were applied to our data (low-risk <9; intermediate-risk 9-12; high-risk >12).

Results:

In our cohort, 40 GCA patients and 95 controls (suspected of GCA) had complete records and were therefore used for analysis. In the patient group, 29 (72.5%) were female and mean (SD) age was 73.3 (1.6). The area under the ROC curve (AUC) was 0.83 (95% CI 0.75 – 0.91). At our optimal cut-off value of 10.5, sensitivity was 80.0% and specificity was 75.8%. In total, 5 patients and 45 controls were stratified as low, 7 patients and 35 controls as intermediate and 28 patients and 15 controls as high-risk.

Conclusion:

The m-GCAPS showed good discrimination in our cohort. Risk stratification of patients looks promising, although cut-off values by Sebastian et al. might need optimization based on population and modification to the GCAPS. Colour Doppler ultrasound is recommended by EULAR as the first-choice diagnostic test to confirm GCA in case of high pre-test probability and exclude GCA for low pre-test probability. The (m-)GCAPS may aid in quantification of this pre-test probability.

References:

[1]Laskou F, Coath F, Mackie SL et al. A probability score to aid the diagnosis of suspected giant cell arteritis. Clin Exp Rheumatol. 2019;37 Suppl 1(2):104–8.

[2]Sebastian A, Tomelleri A, Kayani A et al. Probability-based algorithm using ultrasound and additional tests for suspected GCA in a fast-track clinic. RMD Open. 2020 Sep 1;6(3):e001297.

[3]Dejaco C, Ramiro S, Duftner C et al. EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice. Ann Rheum Dis. 2018 May 1;77(5):636 LP – 643.

Table 1.

Cut-off values of the m-GCAPS stratified into risk categories as proposed by Sebastian et al. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) and the number of patients scoring above or below the cut-off values are described (optimal cut-off value in blue). The total number of patients with a score within low- (red), intermediate- (orange) and high- (green) risk categories are depicted.

GCA+ (N)N=40GCA- (N)N=95Scorem-GCAPSGCA+ (N)GCA- (N)Sens. (%)Spec. (%)PPV (%)NPV (%)Low-risk <95 (12.5%)45 (47.4%)5.5<5.501410014.733.1100>5.540818.5<8.554587.547.441.290>8.53550Intermediate-risk9-127 (17.5%)35 (36.8%)9.5<9.58568058.945.187.5>9.5323910.5<10.58728075.858.290>10.5322311.5<11.510747577.958.888.1>11.53021High-risk>928 (70.0%)15 (15.8%)12.5<12.512807084.265.187>12.5281514.5<14.518895593.778.683.2>14.522619.5<19.537957.510010072>19.530Figure 1.

ROC curve depicting sensitivity and (1-) specificity. The AUC was 0.83 (95.0% CI 0.75-0.91) with an optimal cut-off value of 10.5 (sensitivity 80.0%, specificity 75.8%).

Disclosure of Interests:

None declared

POS0261 DIAGNOSTIC PERFORMANCE AND CLINICAL UTILITY OF TWO REFERRAL RULES FOR INFLAMMATORY ARTHRITIS

Background:

The Rotterdam Early Arthritis Cohort (REACH) rule [1] and Clinical Arthritis RulE (CARE) [2] are both evidence-based and easy-to-use methods developed to identify the presence of inflammatory arthritis (IA) in patients suspected by their general practitioner (GP). However, the clinical utility of both models in daily clinical practice in an independent primary care setting has not yet been established. While developed for recognizing IA, we believe that it is also important that the broader spectrum of inflammatory rheumatic diseases (IRDs) is correctly classified from primary care, to facilitate appropriate referral towards outpatient rheumatology clinics.

Objectives:

The primary objective was to determine the diagnostic performance and clinical utility of the REACH and CARE referral rules in identifying IA in an independent population of unselected suspected patients from primary care. Secondly we will assess the diagnostic performance and clinical utility of both models in identifying IRDs.

Methods:

This prospective observational diagnostic study consisted of adults newly suspected by their GP for the need of referral to the rheumatology outpatient clinic of the Maasstad Hospital in Rotterdam. Primary outcome was IA, consisting of rheumatoid arthritis, axial spondylitis and psoriatic arthritis. Secondary outcome was IRD, defined as IA plus arthritis in systemic disorders such as systemic lupus erythematosus, systemic sclerosis and morbus sjögren. Rheumatologist diagnosis was used as gold standard. To evaluate the clinical performance of the REACH and CARE referral rules in this population, diagnostic accuracy measures were investigated using the Youden index (J) [3]. Moreover, a net benefit approach [4] was used to determine clinical utility of both rules when compared to usual care.

Results:

This study consisted of 250 patients (22.8% male) with a mean age of 50.8 years (SD 13.9 years). In total 42 (17%) patients were diagnosed with IA and 55 (22%) with an IRD. Figure 1 presents the diagnostic performance in IA (Figure 1A) and in IRD (Figure 1B). For the primary outcome, the REACH model shows an AUC of 0.72 (95% CI 0.64-0.80) and the optimal cut-off point is indicated (J). The CARE model shows an AUC of 0.82 (95% CI 0.75-0.88) and at J there is a somewhat higher sensitivity and specificity. When taking the broader spectrum of IRDs as outcome, the AUC was 0.66 (95% CI 0.58-0.74) for the REACH and 0.76 (95% CI 0.69-0.83) for the CARE model. The net benefit analysis with either IA or IRD as outcome showed that the CARE was of the highest clinical value when compared to usual care.

Conclusion:

Both the REACH and CARE model showed a good diagnostic performance for detecting IA in an independent population of unselected suspected patients from primary care. Although not specifically developed to recognize the entire spectrum of IRDs, the CARE shows a good performance in doing so. When evaluating clinical utility, we see that both rules have a net benefit in recognizing IA as well as IRDs compared to usual care, however the CARE shows superiority over the REACH. By using the CARE, over half of all suspected patients can be withheld from expensive outpatient rheumatology care, implied by the high specificity of 70%. These results support the idea that incorporating these easy-to-use methods into primary care could lead to providing patients the right care at the right place and improving value based health care.

References:

[1]ten Brinck RM, van Dijk BT, van Steenbergen HW, le Cessie S, Numans ME. Development and validation of a clinical rule for recognition of early inflammatory arthritis. BMJ Open; 2018: 8

[2]Alves, C. Improving early referral of inflammatory arthritis. In Early detection of patients at risk for rheumatoid arthritis – a challenge for primary and secondary care; 2015: 27-38 Ridderkerk, the Netherlands.

[3]Fluss R, Faraggi D, Reiser B. Estimation of the Youden Index and its associated cutoff point. Biom J; 2005: 47(4): 458-472

[4]Vickers AJ, Elkin EB. Decision curve analysis: a novel method for evaluating prediction models. Med Decis Making; 2006: 26(6): 565-574

Disclosure of Interests:

None declared

AB0367 DIAGNOSTIC DELAY IN PATIENTS WITH GIANT CELL ARTERITIS

Background:

Giant cell arteritis (GCA) is the most common systemic vasculitis in the elderly which can lead to severe complications when treatment is delayed. Therefore, timely diagnosis and start of treatment is essential. Several forms of delay (consultation, referral and diagnostic delay) can contribute to the total delay towards GCA diagnosis. In the Dutch healthcare system, treatment is not started by a general practitioner (GP). When GCA is suspected, GPs refer to specialists. In our hospital, a fast track clinic (FTC) is used to expedite diagnosis. However, information on factors contributing to delay is scarce.

Objectives:

The aim of this study was to describe the different components of delay towards diagnosis in GCA suspected patients in a general hospital, Ziekenhuisgroep Twente (the Netherlands).

Methods:

For this descriptive study, a retrospective cohort consisting of patients with suspected GCA between January 1st 2017 and October 1st 2019 was used to analyse components of delay in diagnosis, as suggested by Prior et al. Consultation delay was defined as the time between start of symptoms and a patient’s first consultation with a GP. Referral delay was defined as the time between a patient’s first consultation with a GP and first visit to the FTC. Diagnostic delay was defined as the time between the first visit to the FTC and treatment initiation. Total delay was defined as the time from symptom onset until start of treatment. Delays were described using the median and interquartile ranges (IQR).

Results:

In our cohort, 206 patients were included for analysis of whom 62 had GCA. Controls (n=144) were suspected of but did not have GCA. Comparing GCA patients with controls, 66.1% and 50.7% were female and the mean (SD) age was 74.2 (9.4) and 70.2 (11.0) years, respectively. In our cohort, the majority of patients (n=42, 67.7%) had cranial GCA (C-GCA). Furthermore, 8 (12.9%) had large vessel GCA (LV-GCA) and 12 (19.4%) had a combination of C-GCA and LV-GCA. For GCA patients, median consultation delay was 2.1 (IQR 0.8-5.8) weeks, referral delay 1.4 (IQR 0.4-4.6) weeks and diagnostic delay 0 (IQR 0-0.1) weeks (Figure 1). For delay regarding consultation and referral, results of controls were comparable to GCA patients. The median total delay was 4.4 weeks (IQR 1.57-10.14) for GCA patients.

Conclusion:

With a median total delay of 4.4 weeks, delay in our cohort is almost half the delay described in a review by Prior et al. This difference might be due to FTC implementation and subsequent awareness in our hospital and by local GPs. Patients generally received treatment within one day after FTC visit. Nevertheless, contribution of consultation and referral delay is not resolved by introduction of the FTC, as shown in our data. Timely diagnosis is essential as severe complications can develop instantly, which emphasizes the need to tackle consultation and referral delay.

References:

[1]Prior JA, Ranjbar H, Belcher J, et al. Diagnostic delay for giant cell arteritis – a systematic review and meta-analysis. BMC Med. 2017;15(1):120.

Table 1.

Baseline characteristics of GCA patients and controls in our retrospective cohort. *CDUS=Colour Doppler Ultrasound; **Temporal Artery Biopsy;***18-FDG-Positron Emission Tomography/Computed Tomography.

GCA patients (n=62)Controls (n=144)RangeRangeGender, % female (n)66.1 (41)50.7 (73)Age (years), mean (SD)74.2 (9.4)51 – 9170.2 (11.0)50 – 97ESR, mean (SD)Missing78.4 (30.3)322 – 12039.9 (32.4)92 – 124CRP, mean (SD)74.7 (60.0)2 - 28335.8 (52.9)0.4 -280Missing16Polymyalgia Rheumatica,% yes (n)21 (13)11.8 (17)Cranial symptoms,% yes (n)80.6 (50)75.0 (108)Vision loss, %yes (n)Compliant with GCA (i.e. AION, central retinal artery occlusion diplopia)27.4 (17)15.3 (22)Diagnostics CDUS* %yes (n)96.8 (60)96.5 (139) TAB** %yes (n)58.1 (36)18.8 (27) PET/CT***%yes (n)40.3 (25)16.0 (23)Figure 1.

Description of consultation (A); referral (B); diagnostic (C) and total (D) delay in weeks for controls (black) and GCA patients (green), stratified for C-GCA (red), LV-GCA (blue) and C/LV-GCA (purple). 1Not possible for controls as no GCA-indicated treatment was started.

Disclosure of Interests:

None declared

Age at Diagnosis Is Determinant for the Outcome of Inflammatory Bowel Disease: Is It a Myth?

INTRODUCTION

Patients with elderly-onset inflammatory bowel disease were previously associated with a less aggressive course of the disease. However, there are conflicting data that need further validation. We aimed to determine the association between age at diagnosis and the development of progressive disease in patients with Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

This cohort study included patients with CD and UC followed in 6 secondary and tertiary care centers in mainland Portugal. Patients were divided into a derivation (80%) cohort and a validation (20%) cohort. The primary outcome was progressive disease. Logistic regression analysis, receiver operating characteristic curves, and the areas under the curve (AUC) were performed. Odds ratios with 95% confidence intervals (CIs) were estimated.

RESULTS

The derivation cohorts included 1245 patients with CD (68% with progressive disease) and 1210 patients with UC (37% with progressive disease), whereas the validation cohorts included 302 patients with CD and 271 patients with UC, respectively, with similar outcome proportions. In our final model, age at diagnosis older than 60 years was significantly associated with a lower risk of developing progressive disease (odds ratio 0.390, 95% CI 0.164-0.923, P = 0.032), with a high discriminative power (AUC 0.724, 95% CI 0.693-754) in patients with CD. However, according to this model, no significant associations were found between age at diagnosis and the risk of developing progressive disease in patients with UC. No differences were observed in the AUC values between the validation and the derivation cohorts.

DISCUSSION

Patients with elderly-onset CD, but not patients with UC, were associated with a less progressive course of the disease.

Rapid test detection of anti-infliximab antibodies: performance comparison with three different immunoassays

BACKGROUND AND AIMS

Therapeutic drug monitoring (TDM) of infliximab (IFX) and anti-infliximab antibodies (ATIs) is essential for treatment optimisation in inflammatory bowel disease (IBD) patients. The aim of this study was to estimate and compare the agreement and accuracy between a new rapid test and three established enzyme-linked immunosorbent assays (ELISAs) to quantify ATIs levels, and to evaluate the impact of exogenous IFX on the performance of these assays.

METHODS

We analysed 200 serum samples from 57 IBD outpatients in IFX induction or maintenance therapy at six IBD centres in Portugal. ATI levels were quantified using the rapid test Quantum Blue® (QB) Anti-Infliximab (Bühlmann) and three established ELISAs: In-House, Theradiag (Lisa Tracker Anti-Infliximab), and Immundiagnostik (IDKmonitor Infliximab). ATIs were quantified in patients' serum samples and spiked samples with exogenous IFX, based on analytical and clinical cutoffs. Qualitative agreement and accuracy were estimated by Cohen's kappa (k) with 95% confidence intervals.

RESULTS

ATIs quantification with clinical cutoffs showed a slight agreement between QB rapid test and In-House [k = 0.163 (0.051-0.276)] and Immundiagnostik [k = 0.085 (0.000-0.177)]. Regarding IFX/ATIs status, the QB rapid test showed a substantial agreement with Theradiag [k = 0.808 (0.729-0.888)] and a fair agreement with In-House [k = 0.343 (0.254-0.431)] and Immundiagnostik [k = 0.217 (0.138-0.297)]. The QB rapid test could not detect ATI-positive levels in samples with exogenous IFX at 5-300 µg/ml. Interference on ATIs detection was observed at exogenous IFX ⩾30 µg/ml for In-house and Immundiagnostik assays.

CONCLUSION

QB rapid test is only suitable to detect ATI-positive levels in the absence of IFX.

Cross-cultural validation of the Portuguese from Portugal version of the test for respiratory and asthma control in kids questionnaire

Summary

Objective. The Test for Respiratory and Asthma Control in Kids (TRACK) is a tool to assess asthma control in preschool children. This study aims to validate the Portuguese from Portugal version of the TRACK questionnaire. Methods. A prospective cohort study was carried out to assess their psychometric characteristics. Caregivers of 141 children under age 5 with asthma symptoms were enrolled. Results. Internal reliability was close to 0.70 (Cronbach's α). The test-retest reliability was 0.87. TRACK scores were different between well, partially, and non-controlled asthma groups (p less than 0.001). Patients rated as having better control showed an increase in TRACK scores. Conclusions. The Portuguese version of the TRACK questionnaire is accurate and reliable for monitoring asthma control. Its use may help to overcome challenges with the management of this age group.

Sustainable plant polyesters as substrates for optical gas sensors

The fast and non-invasive detection of odors and volatile organic compounds (VOCs) by gas sensors and electronic noses is a growing field of interest, mostly due to a large scope of potential applications. Additional drivers for the expansion of the field include the development of alternative and sustainable sensing materials. The discovery that isolated cross-linked polymeric structures of suberin spontaneously self-assemble as a film inspired us to develop new sensing composite materials consisting of suberin and a liquid crystal (LC). Due to their stimuli-responsive and optically active nature, liquid crystals are interesting probes in gas sensing. Herein, we report the isolation and the chemical characterization of two suberin types (from cork and from potato peels) resorting to analyses of gas chromatography–mass spectrometry (GC-MS), solution nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS). The collected data highlighted their compositional and structural differences. Cork suberin showed a higher proportion of longer aliphatic constituents and is more esterified than potato suberin. Accordingly, when casted it formed films with larger surface irregularities and a higher C/O ratio. When either type of suberin was combined with the liquid crystal 5CB, the ensuing hybrid materials showed distinctive morphological and sensing properties towards a set of 12 VOCs (comprising heptane, hexane, chloroform, toluene, dichlormethane, diethylether, ethyl acetate, acetonitrile, acetone, ethanol, methanol, and acetic acid). The optical responses generated by the materials are reversible and reproducible, showing stability for 3 weeks. The individual VOC-sensing responses of the two hybrid materials are discussed taking as basis the chemistry of each suberin type. A support vector machines (SVM) algorithm based on the features of the optical responses was implemented to assess the VOC identification ability of the materials, revealing that the two distinct suberin-based sensors complement each other, since they selectively identify distinct VOCs or VOC groups. It is expected that such new environmentally-friendly gas sensing materials derived from natural diversity can be combined in arrays to enlarge selectivity and sensing capacity.

Chemical composition of rainwater under two events of aerosol transport: A Saharan dust outbreak and wildfires

A one-year campaign of joint sampling of aerosols and precipitation, carried out in León, Spain, allowed to study the impact of two special events that affected the air quality in the north of the country, on rainfall in the city: a period with wildfires and a Saharan dust intrusion. The wildfires that occurred in northern Portugal and northwestern Spain in August 2016 affected the chemistry of rainfall on 15 August 2016, causing an increase in concentrations of NH₄⁺, Na⁺, Cl^-, K⁺, Mg²⁺, Ca²⁺, SO₄^2- and NO₃^- and in the concentrations of organic acids, which was reflected in the levels of soluble and insoluble organic carbon. This led to acidification of rainwater (pH = 4.8). The second precipitation event was registered between 11 and 14 February 2017, during which the rainwater was collected in four daily fractions (P₁, P₂, P₃ and P₄). The rain sample of 12 February (P₂) coincided with a Saharan dust intrusion that reached northern Iberia that day. The chemical composition of P₂ showed an increase in the Ca²⁺ (>800%), Mg²⁺ (71%), Cl^- (62%), and SO₄^2- (33%) concentrations, with respect to P₁. The input of crustal elements to the atmosphere helped to neutralize the P₂ rainwater, causing pH values higher than 6.5. Once the dust intrusion left the north of the Peninsula, the composition of rainwater P₃ and P₄ revealed a mixture of marine contribution with local anthropogenic emissions, as well as a decrease in ion concentrations and conductivity, and an increase in pH values.

Epidemiology of Carbapenemase-Producing Klebsiella pneumoniae in a Portuguese Tertiary Hospital

Background

Carbapenemase-producing Klebsiella pneumoniae (CPKp) are considered a public health problem. To manage this multidrug-resistant organism (MDRO), it is important to identify individuals at higher risk. We describe risk factors for CPKp among a population who acquired this MDRO, in a tertiary hospital Center (THC), from 2017 to 2019.

Methods

Descriptive study, with data from medical record, in a 1100 bed THC, with active surveillance (high risk population at admission and CPKp direct contacts). Participants: patients &gt; =18 years old, with length of stay (LOS) &gt;48 hours, in which CPKp was identified in clinical samples &gt; =48 h after admission and without previous history of this MDRO.

Results

Incidence rate increased from 0.031 (2017) to 0.090 (2018) cases per 1000 patient-days and was 0.081 in 2019 (p = 0.004). Evolution of CPKp proportion was 1.6%, 3.9% and 4.1%, respectively. In 2019, 12 patients (40.0%) were at intensive care when this MDRO was detected. During these 3 years, CPKp was more frequently identified in urine (31.3 - 54.5%) and respiratory products (13.3 - 36.4%). The median LOS until CPKp isolation was 10.0 to 24.0 days and, until discharge, 15.0 to 25.5 days. Fatal outcome occurred in 8 (25.0%) and 7 (23.3%) patients in 2018 and 2019, respectively. Most cases were exposed to antibiotics (81.8 - 90.6%), had a urinary catheter (63.6 - 75.0%) and were dependent for hygiene activities (63.6 - 66.7%). Many had a central line (21.9 - 43.3%), previous surgery (45.5 - 63.3%) and hospital admission in the previous 6 months (27.3 - 40.6%). Along these 3 years, none of these variations was statistically significant.

Conclusions

In this THC, CPKp increased from 2017 to 2018 and remained stable afterwards. It affected mostly male patients, exposed to antibiotics, with urinary catheter and dependent in their hygiene activities. In order to have an adequate CPKp containment strategy it is essential to know the population who acquired this MDRO.

Key messages

CPKp increased from 2017 to 2018 and remained stable afterwards, affecting mostly male patients, exposed to antibiotics, with urinary catheter and dependent in their hygiene activities. In order to have an adequate CPKp containment strategy it is essential to know the population who acquired this MDRO during their stay.

Factors associated with asthma control in 121 preschool children

BACKGROUND AND OBJECTIVE

There are controversial data about risk factors for uncontrolled asthma in preschool children. Objective: This study aims to explore the association between clinical and functional parameters and the lack of asthma control in preschool children.

METHODS

Children 3-5 years-old with asthma and healthy controls were recruited. A questionnaire was used to identify the potential risk factors of uncontrolled asthma as defined by GINA (Global INitiative for Asthma) criteria. Lung function and bronchial reversibility were evaluated through impulse oscillometry (IOS) and spirometry. Adjusted odds ratios (OR) were estimated based on multivariable generalized additive regression models. The discriminative ability of the models was measured by the area under the receiver operating characteristic curve (AUC).

RESULTS

121 children were included, 107 of which had asthma and 14 were healthy controls. Fifty-three patients (50%) had uncontrolled asthma. After adjustment, the variables associated with an increased risk of lack of control were: "More than 3 flare-ups in last 12 months", "moderate to severe rhinitis", "relative variation in post-bronchodilator FVC and FEV1". The AUC of the final models that included variation of FVC or FEV1 were 0.82 and 0.81, respectively. R5-20, R5-20% and AX z-score values of the healthy group were lower than those of children with asthma.

CONCLUSION

In preschool children, clinical and functional parameters are associated with uncontrolled asthma. More studies are needed to confirm usefulness of the IOS.

Impact of wood combustion on indoor air quality

The incomplete wood combustion in appliances operated in batch mode is a recognised source of both in- and outdoor airborne pollutants, especially particulate matter (PM). Data on pollutant levels and PM characteristics in households with wood burning devices in developed countries are scarce with most studies describing stove change out programmes or other intervention measures. The aim of the present study was to simultaneously evaluate indoor and outdoor concentrations of CO, CO₂ and PM₁₀ during the operation of wood burning appliances (open fireplace and woodstove) in unoccupied rural households. PM₁₀ samples were analysed for water soluble inorganic ions, major and trace elements, organic carbon (OC), elemental carbon (EC), and detailed organic speciation. The CO 8-hour average concentrations did not exceed the protection limit despite the sharp increases observed in relation to background levels. During the open fireplace operation, PM₁₀ levels rose up 12 times compared to background concentrations, while the airtight stove resulted in a 2-fold increase. The inhalation cancer risk of particulate bound PAHs in the room equipped with woodstove was estimated to be negligible while the long-term exposure to PAH levels measured in the fireplace room may contribute to the development of cancer. The excess lifetime cancer risk resulting from the particle-bound Cr(VI) exposure during the fireplace and woodstove operation was higher than 1.0 × 10^-6 and 1.0 × 10^-5, respectively. Levoglucosan was one of the most abundant individual species both indoors and outdoors. This study underlines air pollution hazards and risks arising from the operation of traditional wood burning appliances.

Aethalometer measurements in a road tunnel: A step forward in the characterization of black carbon emissions from traffic

A sampling campaign was conducted in the Liberdade Avenue tunnel (Braga, Portugal) during a week (with 56,000 vehicles) to monitor black carbon (eBC-equivalent black carbon) by means of an Aethalometer AE-31, and gaseous pollutants (CO₂, CO, NO_x). Inside the tunnel, the mean eBC mass concentration was 21 ± 10 μg m^-3, reaching a maximum hourly value of 49.0 μg m^-3. An hourly and weekday-weekend study was carried out. Regarding the Absorption Ångström exponent (AAE), a mean value of 0.97 ± 0.10 was obtained, for a source of practically pure traffic. There was a positive significant correlation between eBC and the number of light vehicles (r = 0.47; p < 0.001) and between eBC and the gaseous emissions: CO (r = 0.67; p < 0.001), CO₂ (r = 0.71; p < 0.001), NO (r = 0.63; p < 0.001) and NO₂ (r = 0.70; p < 0.001). The mean black carbon emission factors (EF_BC) inside the tunnel were 0.31 ± 0.08 g (kg fuel)^-1 and 0.11 ± 0.08 mg veh^-1 km^-1, similar to those found in other studies for gasoline and diesel vehicles in road tunnels.

Virtual Reality-Based Cognitive Stimulation to Improve Cognitive Functioning in Community Elderly: A Controlled Study

The advantages of using naturalistic virtual reality (VR) environments based on everyday life tasks for cognitive intervention in the elderly are not yet well understood. The literature suggests that the similarity of such exercises with real life activities may improve generalizability by extending the transfer of gains of training to everyday living. This study aimed to investigate the gains associated with this ecologically-oriented virtual reality cognitive stimulation (VR-CS) versus standard cognitive stimulation in the elderly. Forty-three healthy older adults were divided into two groups: an experimental group underwent a VR-based cognitive stimulation and an active control group underwent a paper-and-pencil cognitive stimulation. The outcomes assessed at the pre-treatment and posttreatment assessment consisted in well-established tests for cognitive and executive functioning, depression, subjective well-being, and functionality. The results showed positive outcomes on dimensions of general cognition, executive functioning, attention, and visual memory in the group that underwent VR-CS. Improvements in executive functioning in this group was supported by consistent evidence of increases in attention abilities but little evidence of increases in memory abilities. Both effects may have contributed to improvements in general cognition. Further studies are needed to test whether these effects may extend to well-being and functionality in cognitively impaired older adults.

Plantar flexion, dorsiflexion, range of movement and hindfoot deviation are important determinants of foot function in children

PURPOSE

Paediatric foot surgery is often performed to restore anatomical shape or range of movement (ROM). The purpose of this study was to determine how foot morphology and ROM are associated with foot function in children aged five to 16 years of age.

METHODS

Participants included 89 patients with foot disorders and 58 healthy controls. In addition to measuring children's foot alignment and ankle ROM, children and parents completed the Oxford Ankle and Foot Questionnaire (OxAFQ).

RESULTS

Mean age was 10.3 years for patients and 10.6 years for controls; 53 of 89 patients had clubfoot. All foot measurements and scores on the OxAFQ significantly differed (p < 0.001) between patients and controls. Patients and their parents significantly differed on the physical (p = 0.03) and emotional (p = 0.02) domains of the OxAFQ, with parents' ratings being lower than their children. Moderate correlations (r = 0.54 to 0.059; p < 0.001) were found between physical domain (reported by parents on the OxAFQ) and dorsiflexion-knee flexed, and foot- arc-of-movement. Moderate correlations were found between physical domain (reported by children on OxAFQ) and foot-arc-of-movement (r = 0.56; p < 0.001). Patients in the surgical group showed moderate correlations (r = 0.57;, p < 0.001) between physical domain (reported by children on OxAFQ) and plantar flexion, and foot arc-of-movement. The control group and the patients in non-surgical subgroup showed no significant correlations.

CONCLUSION

Plantar flexion, arc of ankle ROM and hindfoot alignment impact foot function in children with foot deformities. Parents report significantly lower scores on the OxAFQ when judging foot functioning.

LEVEL OF EVIDENCE

Level II. Prognostic Studies.

Unusual winter Saharan dust intrusions at Northwest Spain: Air quality, radiative and health impacts

Saharan air masses can transport high amounts of mineral dust particles and biological material to the Iberian Peninsula. During winter, this kind of events is not very frequent and usually does not reach the northwest of the Peninsula. However, between 21 and 22 February 2016 and between 22 and 23 February 2017, two exceptional events were registered in León (Spain), which severely affected air quality. An integrative approach including: i) typical synoptic conditions; ii) aerosol chemical composition; iii) particle size distributions; iv) pollen concentration; v) aerosol optical depth (AOD); vi) radiative forcing and vii) estimation of the impact of aerosols in the respiratory tract, was carried out. In the global characterization of these events, the exceedance of the PM₁₀ daily limit value, an increase in the coarse mode and a rise in the iron concentration were observed. On the 2016 event, an AOD and extinction-related Ångström exponent clearly characteristic of desert aerosol (1.1 and 0.05, respectively) were registered. Furthermore, pollen grains not typical of flowering plants in this period were identified. The chemical analysis of the aerosol from the 2017 event allowed us to confirm the presence of the main elements associated with mineral sources (aluminum, calcium, and silica concentrations). An increase in the SO₄^2-, NO₃^- and Cl^- concentrations during the Saharan dust intrusion was also noted. However, in this event, there was no presence of atypical pollen types. The estimated dust radiative forcing traduced a cooling effect for surface and atmosphere during both events, corroborated by trends of radiative flux measurements. The estimated impact on the respiratory tract regions of the high levels of particulate matter during both Saharan dust intrusions showed high levels for the respirable fraction.

Bracing in clubfoot: do we know enough?

PURPOSE

The Ponseti method is widely used in clubfoot treatment. Long-term follow-up shows high patient satisfaction and excellent functional outcomes. Clubfoot tendency to relapse is a problem yet to solve. Given the importance of bracing in relapse prevention, we ought to discuss current knowledge and controversies about bracing.

METHODS

We describe types of braces used, with its advantages and disadvantages, suggesting bracing schedules and duration. We identify bracing problems and pinpoint strategies to promote adherence to bracing.

RESULTS

When treating a clubfoot by the Ponseti method, the corrected foot should be held in an abducted and dorsiflexed position, in a foot abduction brace (FAB), with two shoes connected by a bar. The brace is applied after the clubfoot has been completely corrected by manipulation, serial casting and possibly Achilles tenotomy. Bracing is recommended until four to five years of age and needs to be fitted to the individual patient, based on age, associated relapse rate and timing when correction was finished. Parental non-adherence to FAB use can affect 34% to 61% of children and results in five- to 17-fold higher odds of relapse. In patients who have recurrent adherence problems, a unilateral lower leg custom-made orthosis can be considered as a salvage option. Healthcare providers must communicate with patients regarding brace wearing, set proper expectations and ensure accurate use.

CONCLUSION

Bracing is essential for preventing clubfoot relapse. Daily duration and length of bracing required to prevent recurrence is still unknown. Prospective randomized clinical trials may bring important data that will influence clinicians' and families' choices regarding bracing.

LEVEL OF EVIDENCE

V.