New Insights in Microbial Species Predicting Lung Function Decline in CF: Lessons from the MucoFong Project

Several predictive models have been proposed to understand the microbial risk factors associated with cystic fibrosis (CF) progression. Very few have integrated fungal airways colonisation, which is increasingly recognized as a key player regarding CF progression. To assess the association between the percent predicted forced expiratory volume in 1 s (ppFEV1) change and the fungi or bacteria identified in the sputum, 299 CF patients from the “MucoFong” project were included and followed-up with over two years. The relationship between the microorganisms identified in the sputum and ppFEV1 course of patients was longitudinally analysed. An adjusted linear mixed model analysis was performed to evaluate the effect of a transient or chronic bacterial and/or fungal colonisation at inclusion on the ppFEV1 change over a two-year period. Pseudomonas aeruginosa, Achromobacter xylosoxidans, Stenotrophomonas maltophilia, and Candida albicans were associated with a significant ppFEV1 decrease. No significant association was found with other fungal colonisations. In addition, the ppFEV1 outcome in our model was 11.26% lower in patients presenting with a transient colonisation with non-pneumoniae Streptococcus species compared to other patients. These results confirm recently published data and provide new insights into bacterial and fungal colonisation as key factors for the assessment of lung function decline in CF patients.

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Discrepancy between Lung Function Measurements at Home and in the Hospital in Children with Asthma and CF

Journal of Clinical Medicine ◽

10.3390/jcm9061617 ◽

2020 ◽

Vol 9 (6) ◽

pp. 1617 ◽

Cited By ~ 2

Author(s):

Frederick L.G.R. Gerzon ◽

Quirijn Jöbsis ◽

Michiel A.G.E. Bannier ◽

Bjorn Winkens ◽

Edward Dompeling

Keyword(s):

Lung Function ◽

Mixed Model ◽

Linear Mixed Model ◽

Early Stage ◽

Home Monitoring ◽

Clinical Situation ◽

Forced Expiratory Volume ◽

Mixed Model Analysis ◽

Children With Asthma ◽

At Home

The Coronavirus pandemic stresses the importance of eHealth techniques to monitor patients at home. Home monitoring of lung function in asthma and cystic fibrosis (CF) may help to detect deterioration of lung function at an early stage, but the reliability is unclear. We investigated whether lung function measurements at home were comparable to measurements during clinical visits. We analysed prospectively collected data of two one-year observational cohort studies in 117 children (36 with CF and 81 with asthma). All patients performed forced expiratory volume in one second (FEV1) measurements with a monitor at home. Paired FEV1 measurements were included if the measurement on the home monitor was performed on the same day as the FEV1 measurement on the pneumotachometer during a two monthly clinical visit. Bland-Altman plots and linear mixed model analysis were used. The mean difference (home measurement was subtracted from clinical measurement) in FEV1 was 0.18 L in CF (95% confidence interval (CI) 0.08–0.27 L; p < 0.001) and 0.12 L in asthma (95%CI 0.05–0.19 L; p < 0.001). FEV1 measurements at home were significantly lower than clinically obtained FEV1 measurements, which has implications for the application of this technique in the daily clinical situation.

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Chronisch pulmonale Erkrankungen bei Kindern: Chancen von E-Health zur Verbesserung der Therapiesteuerung nutzen

Karger Kompass Pneumologie ◽

10.1159/000510893 ◽

2020 ◽

Vol 8 (5) ◽

pp. 264-265

Author(s):

Maximilian Jorczyk

Keyword(s):

Lung Function ◽

Mixed Model ◽

Linear Mixed Model ◽

Early Stage ◽

Home Monitoring ◽

Clinical Situation ◽

Forced Expiratory Volume ◽

Mixed Model Analysis ◽

One Year ◽

At Home

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Lung function over the life course of paediatric and adult patients with cystic fibrosis from a large multi-centre registry

Scientific Reports ◽

10.1038/s41598-020-74502-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Arul Earnest ◽

Farhad Salimi ◽

Claire E. Wainwright ◽

Scott C. Bell ◽

Rasa Ruseckaite ◽

...

Keyword(s):

Cystic Fibrosis ◽

Lung Function ◽

Mixed Model ◽

Linear Mixed Model ◽

Pancreatic Insufficiency ◽

Forced Expiratory Volume ◽

Rate Of Change ◽

Data Registry ◽

Mortality Outcome ◽

The Impact

Abstract A key measure of lung function in people with Cystic Fibrosis (CF) is Forced Expiratory Volume in the first second FEV1 percent predicted (FEV1pp). This study aimed to address challenges in identifying predictors of FEV1pp, specifically dealing with non-linearity and the censoring effect of death. Data was obtained from a large multi-centre Australian Cystic Fibrosis Data Registry (ACFDR). A linear mixed model was used to study FEV1pp as the endpoint. There were 3655 patients (52.4% male) included in our study. Restricted cubic splines were used to fit the non-linear relationship between age of visit and FEV1pp. The following predictors were found to be significant in the multivariate model: age of patient at visit, BMI z-score, age interaction with lung transplantation, insulin dependent diabetes, cirrhosis/portal hypertension, pancreatic insufficiency, Pseudomonas aeruginosa infection and baseline variability in FEV1pp. Those with P. aeruginosa infection had a lower mean difference in FEV1pp of 4.7 units, p < 0.001 compared to those who did not have the infection. Joint modelling with mortality outcome did not materially affect our findings. These models will prove useful for to study the impact of CFTR modulator therapies on rate of change of lung function among patients with CF.

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Thoracic dust exposure is associated with lung function decline in cement production workers

European Respiratory Journal ◽

10.1183/13993003.02061-2015 ◽

2016 ◽

Vol 48 (2) ◽

pp. 331-339 ◽

Cited By ~ 6

Author(s):

Karl-Christian Nordby ◽

Hilde Notø ◽

Wijnand Eduard ◽

Marit Skogstad ◽

Anne Kristin Fell ◽

...

Keyword(s):

Lung Function ◽

Mixed Model ◽

Statistical Modelling ◽

Forced Expiratory Volume ◽

Dust Exposure ◽

Lung Function Decline ◽

Lung Volumes ◽

Cement Production ◽

Yearly Change ◽

Predicted Values

We hypothesised that exposure to workplace aerosols may lead to lung function impairment among cement production workers.Our study included 4966 workers in 24 cement production plants. Based on 6111 thoracic aerosol samples and information from questionnaires we estimated arithmetic mean exposure levels by plant and job type. Dynamic lung volumes were assessed by repeated spirometry testing during a mean follow-up time of 3.5 years (range 0.7–4.6 years). The outcomes considered were yearly change of dynamic lung volumes divided by the standing height squared or percentage of predicted values. Statistical modelling was performed using mixed model regression. Individual exposure was classified into quintile levels limited at 0.09, 0.89, 1.56, 2.25, 3.36, and 14.6 mg·m−3, using the lowest quintile as the reference. Employees that worked in administration were included as a second comparison group.Exposure was associated with a reduction in forced expiratory volume in 1 s (FEV1), forced expiratory volume in 6 s and forced vital capacity. For FEV1% predicted a yearly excess decline of 0.84 percentage points was found in the highest exposure quintile compared with the lowest.Exposure at the higher levels found in this study may lead to a decline in dynamic lung volumes. Exposure reduction is therefore warranted.

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Reducing Aggression by Developing Emotional and Inhibitory Control

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18105263 ◽

2021 ◽

Vol 18 (10) ◽

pp. 5263

Author(s):

Miriam Romero-López ◽

María Carmen Pichardo ◽

Ana Justicia-Arráez ◽

Judit Bembibre-Serrano

Keyword(s):

Psychosocial Development ◽

Mixed Model ◽

Linear Mixed Model ◽

Generalized Linear Mixed Model ◽

Emotional Control ◽

Control Group ◽

Post Intervention ◽

Mixed Model Analysis ◽

Intervention Measures ◽

Experimental Group

The objective of this study is to measure the effectiveness of a program on improving inhibitory and emotional control among children. In addition, it is assessed whether the improvement of these skills has an effect on the reduction of aggressive behavior in pre-school children. The participants were 100 children, 50 belonging to the control group and 50 to the experimental group, aged between 5 and 6 years. Pre-intervention and post-intervention measures of inhibitory and emotional control (BRIEF-P) and aggression (BASC) were taken. A Generalized Linear Mixed Model analysis (GLMM) was performed and found that children in the experimental group scored higher on inhibitory and emotional control compared to their peers in the control group. In addition, these improvements have an effect on the decrease in aggressiveness. In conclusion, preventive research should have among its priorities the design of such program given their implications for psychosocial development.

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Methods to Assess Fat Mass in Infants and Young Children: A Comparative Study Using Skinfold Thickness and Air-Displacement Plethysmography

Life ◽

10.3390/life11020075 ◽

2021 ◽

Vol 11 (2) ◽

pp. 75

Author(s):

Stefanie M. P. Kouwenhoven ◽

Nadja Antl ◽

Jos W. R. Twisk ◽

Berthold V. Koletzko ◽

Martijn J. J. Finken ◽

...

Keyword(s):

Young Children ◽

Fat Mass ◽

Mixed Model ◽

Linear Mixed Model ◽

Correlation Coefficients ◽

Skinfold Thickness ◽

Limited Information ◽

Air Displacement Plethysmography ◽

Mixed Model Analysis ◽

Infants And Young Children

Background: Traditionally, fat mass is estimated using anthropometric models. Air-displacement plethysmography (ADP) is a relatively new technique for determining fat mass. There is limited information on the agreement between these methods in infants and young children. Therefore we aimed to longitudinally compare fat mass percentage values predicted from skinfold thicknesses (SFTs) and ADP in healthy infants and young children. Methods: Anthropometry and body composition were determined at the ages of 1, 4, and 6 months and 2 years. We quantified the agreement between the two methods using the Bland–Altman procedure, linear mixed-model analysis, and intra-class correlation coefficients (ICC). Results: During the first 6 months of life, fat mass% predicted with SFT was significantly different from that measured with ADP in healthy, term-born infants (n = 245). ICCs ranged from 0.33 (at 2 years of age) and 0.47 (at 4 months of age). Although the mean difference (bias) between the methods was low, the Bland–Altman plots showed proportional differences at all ages with wide limits of agreement. Conclusions: There is poor agreement between ADP and SFTs for estimating fat mass in infancy or early childhood. The amount of body fat was found to influence the agreement between the methods.

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Lung function decline is associated with serum uric acid in Korean health screening individuals

Scientific Reports ◽

10.1038/s41598-021-89678-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kyung-Min Ahn ◽

Suh-Young Lee ◽

So-Hee Lee ◽

Sun-Sin Kim ◽

Heung-Woo Park

Keyword(s):

Uric Acid ◽

Lung Function ◽

Serum Uric Acid ◽

Uric Acid Level ◽

Acid Level ◽

Serum Uric Acid Level ◽

Forced Expiratory Volume ◽

Linear Regression Models ◽

Lung Function Decline ◽

Health Screenings

AbstractWe performed a retrospective cohort study of 19,237 individuals who underwent at least three health screenings with follow-up periods of over 5 years to find a routinely checked serum marker that predicts lung function decline. Using linear regression models to analyze associations between the rate of decline in the forced expiratory volume in 1 s (FEV1) and the level of 10 serum markers (calcium, phosphorus, uric acid, total cholesterol, total protein, total bilirubin, alkaline phosphatase, aspartate aminotransferase, creatinine, and C-reactive protein) measured at two different times (at the first and third health screenings), we found that an increased uric acid level was significantly associated with an accelerated FEV1 decline (P = 0.0014 and P = 0.037, respectively) and reduced FEV1 predicted % (P = 0.0074 and P = 8.64 × 10–7, respectively) at both visits only in non-smoking individuals. In addition, we confirmed that accelerated forced vital capacity (FVC) and FEV1/FVC ratio declines were observed in non-smoking individuals with increased serum uric acid levels using linear mixed models. The serum uric acid level thus potentially predicts an acceleration in lung function decline in a non-smoking general population.

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Factors influencing the occurrence of high ultimate pH in three muscles of lamb carcasses in Australia

Animal Production Science ◽

10.1071/an14315 ◽

2014 ◽

Vol 54 (10) ◽

pp. 1853 ◽

Cited By ~ 8

Author(s):

N. G. McPhail ◽

J. L. Stark ◽

A. J. Ball ◽

R. D. Warner

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Rectus Femoris ◽

Carcass Weight ◽

Mixed Model Analysis ◽

Factors Influencing ◽

South Wales ◽

Generalised Linear Mixed Model ◽

Processing Plants ◽

Few Data

Chilled lamb meat exported from Australia has, on occasions, been rejected by importing countries due to greening, after only 6 weeks of storage time. Greening is known to be more prevalent in high ultimate pH (pHu) beef meat (>5.9). There are few data available for lamb carcasses in Australia on the occurrence of high pHu meat, which may have an impact on the understanding and control of quality and greening during storage. The aim of this project was to determine the prevalence of, and influencing factors for, high pHu meat in a range of muscle types in lamb carcasses in Australia. Muscle pHu data were collected from a total of 1614 carcasses from 78 lots at four lamb processing plants in Victoria and New South Wales in autumn and spring of 2013. The pHu of the knuckle (rectus femoris), rack (longissimus) and blade (infraspinatus) was measured and data on carcass and lot characteristics were recorded. Data were subjected to restricted maximum likelihood and generalised linear mixed model analysis. The mean pHu of the knuckle, rack and shoulder were 6.06, 5.79 and 6.12 respectively, and the main factors influencing muscle pHu and occurrence of dark-cutting were breed, season, electrical stimulation and carcass weight. Merino lambs had a higher pHu in the blade and knuckle than did other breeds (P < 0.05, P < 0.01 respectively). Lambs processed in autumn had a higher predicted pHu in the blade and knuckle and a higher percentage dark-cutting (DC; pHu >6.0) for those muscles, than did those processed in spring (P < 0.05). Carcasses that had been electrically stimulated had a higher %DC and a higher pHu in all three muscles (P < 0.05). Carcass weight had a significant effect on the pHu of all three muscles (P < 0.001), with heavier carcasses having a lower pHu and lower %DC. The pHu of the rack was not a reliable predictor for the pHu in other muscles of the lamb carcass. In conclusion, the high occurrence of DC in the muscles, particularly the blade and knuckle, suggests that these muscles may be at risk for producing greening in the vacuum bag during storage.

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Size-related boldness is not altered by stomach flushing in a terrestrial salamander

Amphibia-Reptilia ◽

10.1163/15685381-bja10054 ◽

2021 ◽

pp. 1-6

Author(s):

Sebastiano Salvidio ◽

Andrea Costa ◽

Fabrizio Oneto

Keyword(s):

Body Condition ◽

Mixed Model ◽

Linear Mixed Model ◽

Animal Personality ◽

Model Analysis ◽

Mixed Model Analysis ◽

Linear Mixed Model Analysis ◽

Before And After ◽

Trophic Strategy ◽

The Relationship

Abstract Animal personality is a relatively neglected field in amphibian research. In this study we assessed the influence of stomach flushing, a non-lethal technique used in amphibian dietary studies, on the boldness behaviour of the cave salamander Speleomantes strinatii. The time of emergence from a shelter located in an unfamiliar environment (a proxy for individual boldness) was measured in 26 cave salamanders before and after stomach flushing, while 14 non-flushed salamanders were tested as controls. Boldness was a repeatable behaviour for salamanders and larger individuals emerged from their shelter more rapidly than smaller ones. Linear mixed model analysis showed that flushing, sex and body condition had no effect on this behaviour. These findings are promising in the framework of the study of salamander personality. In particular, our results will be useful when exploring the relationship between individual trophic strategy and boldness, aggression or exploration behaviours in terrestrial salamanders.

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Maximin Efficiencies under Treatment-Dependent Costs and Outcome Variances for Parallel, AA/BB, and AB/BA Designs

Computational and Mathematical Methods in Medicine ◽

10.1155/2018/8025827 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15

Author(s):

Math J. J. M. Candel

Keyword(s):

Mixed Model ◽

Linear Mixed Model ◽

Optimal Allocation ◽

Power Level ◽

Equal Treatment ◽

Small Samples ◽

Asymptotic Results ◽

Crossover Designs ◽

Mixed Model Analysis ◽

Intraclass Correlations

If there are no carryover effects, AB/BA crossover designs are more efficient than parallel (A/B) and extended parallel (AA/BB) group designs. This study extends these results in that (a) optimal instead of equal treatment allocation is examined, (b) allowance for treatment-dependent outcome variances is made, and (c) next to treatment effects, also treatment by period interaction effects are examined. Starting from a linear mixed model analysis, the optimal allocation requires knowledge on intraclass correlations in A and B, which typically is rather vague. To solve this, maximin versions of the designs are derived, which guarantee a power level across plausible ranges of the intraclass correlations at the lowest research costs. For the treatment effect, an extensive numerical evaluation shows that if the treatment costs of A and B are equal, or if the sum of the costs of one treatment and measurement per person is less than the remaining subject-specific costs (e.g., recruitment costs), the maximin crossover design is most efficient for ranges of intraclass correlations starting at 0.15 or higher. For other cost scenarios, the maximin parallel or extended parallel design can also become most efficient. For the treatment by period interaction, the maximin AA/BB design can be proven to be the most efficient. A simulation study supports these asymptotic results for small samples.

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