Association of Change in Body Mass Index With Incidence and Progression of the Structural Defects of Hip Osteoarthritis: Data From the Osteoarthritis Initiative and the Cohort Hip and Cohort Knee study

Objective: To define the association between change in body mass index (BMI) and the incidence and progression of structural defects of hip osteoarthritis as assessed by radiography. Methods: We used data from 2 independent cohort studies: the Osteoarthritis Initiative (OAI) and the Cohort Hip and Cohort Knee (CHECK) study. Our exposure was change in BMI from baseline to 4–5 years’ follow-up. Our outcomes were the incidence and progression of structural defects of hip osteoarthritis as assessed using a modified Croft grade in OAI and the Kellgren/Lawrence grade in the CHECK study. To study incidence, we created incidence cohorts of hips without definite overall structural defects at baseline (i.e., grade <2) and then investigated the odds of hips having definite overall structural defects at follow-up (i.e., grade ≥2). To study progression, we created progression cohorts of hips with definite overall structural defects at baseline (i.e., grade ≥2) and then investigated the odds of having a grade increase of ≥1 from baseline to follow-up. Results: There was a total of 5,896 and 1,377 hips in the incidence cohorts, and 303 and 129 hips in the progression cohorts for the OAI and CHECK study, respectively. Change in BMI (decrease or increase) was not associated with any change in odds of the incidence or progression of definite structural defects of hip osteoarthritis in either the OAI or CHECK cohorts. Conclusion: Weight loss may not be an effective strategy for preventing, slowing, or delaying the structural defects of hip osteoarthritis over 4–5 years

Association between change in body mass index and knee and hip replacements: a survival analysis of 7 to 10 years using multi-cohort data

Objective: To define the association between change in body mass index (BMI) and the risk of knee and hip replacement. Methods: We used data from three independent cohort studies: the Osteoarthritis Initiative (OAI), the Multicenter Osteoarthritis Study (MOST), and the Cohort Hip and Cohort Knee (CHECK) study, which collected data from adults (45 to 79 years of age) with or at risk of clinically significant knee osteoarthritis. We conducted Cox proportional hazards regression analysis with clustering of both knees and hips per person to determine the association between change in BMI (our exposure of interest) and the incidence of primary knee and hip replacement over 7 to 10 years’ follow-up. Change in BMI (in kg/m2) was calculated between baseline and the last follow-up visit before knee or hip replacement, or – for knees and hips that were not replaced – the last follow-up visit. Results: A total of 16,362 knees from 8181 participants, and 16,406 hips from 8203 participants, were eligible for inclusion in our knee and hip analyses, respectively. Change in BMI was positively associated with the risk of knee replacement (adjusted hazard ratio 1.03; 95% confidence interval [CI] 1.00 to 1.06) but not hip replacement (adjusted hazard ratio 1.00; 95% CI 0.95 to 1.04). The association between change in BMI and knee replacement was independent of participants’ BMI category at baseline (i.e., normal, overweight, or obese). Conclusion: Public health strategies incorporating weight loss interventions could reduce the burden of knee but not hip replacement surgery

Researchers in rheumatology should avoid categorization of continuous predictor variables

BACKGROUND: Rheumatology researchers often categorize continuous predictor variables. We aimed to show how this practice may alter results from observational studies in rheumatology. METHODS: We conducted and compared the results of two analyses of the association between our predictor variable (percentage change in body mass index [BMI] from baseline to four years) and two outcome variable domains of structure and pain in knee and hip osteoarthritis. These two outcome variable domains covered 26 different outcomes for knee and hip combined. In the first analysis (categorical analysis), percentage change in BMI was categorized as ≥ 5% decrease in BMI, < 5% change in BMI, and ≥ 5% increase in BMI, while in the second analysis (continuous analysis), it was left as a continuous variable. In both analyses (categorical and continuous), we used generalized estimating equations with a logistic link function to investigate the association between the percentage change in BMI and the outcomes. RESULTS: For eight of the 26 investigated outcomes (31%), the results from the categorical analyses were different from the results from the continuous analyses. These differences were of three types: 1) for six of these eight outcomes, while the continuous analyses revealed associations in both directions (i.e., a decrease in BMI had one effect, while an increase in BMI had the opposite effect), the categorical analyses showed associations only in one direction of BMI change, not both; 2) for another one of these eight outcomes, the categorical analyses suggested an association with change in BMI, while this association was not shown in the continuous analyses (this is potentially a false positive association); 3) for the last of the eight outcomes, the continuous analyses suggested an association of change in BMI, while this association was not shown in the categorical analyses (this is potentially a false negative association). CONCLUSIONS: Categorization of continuous predictor variables alters the results of analyses and could lead to different conclusions; therefore, researchers in rheumatology should avoid it

Association of Decrease in Body Mass Index With Reduced Incidence and Progression of the Structural Defects of Knee Osteoarthritis: A Prospective Multi-Cohort Study

Objective: To define the association between change in body mass index (BMI) and the incidence and progression of the structural defects of knee osteoarthritis as assessed by radiography. Methods: Radiographic analyses of knees at baseline and at 4–5 years of follow-up were obtained from the following 3 independent cohort studies: the Osteoarthritis Initiative (OAI) study, the Multicenter Osteoarthritis Study (MOST), and the Cohort Hip and Cohort Knee (CHECK) study. Logistic regression analyses using generalized estimating equations, with clustering of both knees within individuals, were used to investigate the association between change in BMI from baseline to 4–5 years of follow-up and the incidence and progression of knee osteoarthritis. Results: A total of 9,683 knees (from 5,774 participants) in an “incidence cohort” and 6,075 knees (from 3,988 participants) in a “progression cohort” were investigated. Change in BMI was positively associated with both the incidence and progression of the structural defects of knee osteoarthritis. The adjusted odds ratio (OR) for osteoarthritis incidence was 1.05 (95% confidence interval [95% CI] 1.02–1.09), and the adjusted OR for osteoarthritis progression was 1.05 (95% CI 1.01–1.09). Change in BMI was also positively associated with degeneration (i.e., narrowing) of the joint space and with degeneration of the femoral and tibial surfaces (as indicated by osteophytes) on the medial but not on the lateral side of the knee. Conclusion: A decrease in BMI was independently associated with lower odds of incidence and progression of the structural defects of knee osteoarthritis and could be a component in preventing the onset or worsening of knee osteoarthritis

Investigation of the association of weight loss with radiographic hip osteoarthritis in older community-dwelling female adults

Objective: Most guidelines recommending weight loss for hip osteoarthritis are based on research on knee osteoarthritis. Prior studies found no association between weight loss and hip osteoarthritis, but no previous studies have targeted older adults. Therefore, we aimed to determine whether there is any clear benefit of weight loss for radiographic hip osteoarthritis in older adults because weight loss is associated with health risks in older adults. Methods: We used data from white female participants aged ≥65 years from the Study of Osteoporotic Fractures. Our exposure of interest was weight change from baseline to follow-up at 8 years. Our outcomes were the development of radiographic hip osteoarthritis (RHOA) and the progression of RHOA over 8 years. Generalized estimating equations (clustering of 2 hips per participant) were used to investigate the association between exposure and outcomes adjusted for major covariates. Results: There was a total of 11,018 hips from 5509 participants. There was no associated benefit of weight loss for either of our outcomes. The odds ratios (95% confidence intervals) for the development and progression of RHOA were 0.99 (0.92–1.07) and 0.97 (0.86–1.09) for each 5% weight loss, respectively. The results were consistent in sensitivity analyses where participants were limited to those who reported trying to lose weight and who also had a body mass index in the overweight or obese range. Conclusion: Our findings suggest no associated benefit of weight loss in older female adults in the structure of the hip joint as assessed by radiography

Effect of severe compared with moderate energy restriction on physical activity among postmenopausal female adults with obesity: a prespecified secondary analysis of the Type of Energy Manipulation for Promoting optimum metabolic health and body composition in Obesity (TEMPO) Diet randomized controlled Trial

Background: An under-explored strategy for increasing physical activity is the dietary treatment of obesity, but empirical evidence is lacking. Objectives: We aimed to compare the effects of weight loss via severe as opposed to moderate energy restriction on physical activity over 36 mo. Methods: A total of 101 postmenopausal female adults (45-65 y, BMI 30-40 kg/m2, <180 min/wk of structured exercise) were randomly assigned to either 12 mo of moderate energy restriction (25%-35% of energy requirement) with a food-based diet, or a severe intervention involving 4 mo of severe energy restriction (65%-75% of energy requirement) with a total meal replacement diet, followed by 8 mo of moderate energy restriction. Physical activity was encouraged, but no tailored or supervised exercise prescription was provided. Physical activity was assessed with an accelerometer worn for 7 d before baseline (0 mo) and 0.25, 1, 4, 6, 12, 24, and 36 mo after intervention commencement. Results: Compared with the moderate group, the severe group exhibited greater mean: total volume of physical activity; duration of moderate-to-vigorous-intensity physical activity (MVPA); duration of light-intensity physical activity; step counts, as well as lower mean duration of sedentary time. All these differences (except step counts) were apparent at 6 mo [e.g., 1006 metabolic equivalent of task (MET)-min/wk; 95% CI: 564, 1449 MET-min/wk for total volume of physical activity], and some were also apparent at 4 and/or 12 mo. There were no differences between groups in the 2 other outcomes investigated (self-efficacy to regulate exercise; and proportion of participants meeting the WHO's 2020 Physical Activity Guidelines for MVPA). When the analyses were adjusted for weight at each time point, the differences between groups were either attenuated or abolished. Conclusions: Among female adults with obesity, including a dietary component to reduce excess body weight - notably one involving severe energy restriction - could potentially enhance the effectiveness of physical activity interventions. This trial was registered at www.anzctr.org.au as ACTRN12612000651886

Borda Oeste do Pantanal e Maciço do Urucum em Corumbá, MS: área prioritária para conservação da biodiversidade.

A região do Maciço do Urucum e adjacências apresenta característica ímpar dentro do Estado do Mato Grosso Sul e do Brasil, em função das influências que recebe de ecossistemas vizinhos, dos endemismos existentes e da ocorrência de espécies de distribuição no Brasil restrita a esta área. A região é uma península com 1.311 km2 de áreas não inundáveis que penetra o Pantanal. Nesta estreita faixa, as atividades de mineração, de indústrias, o crescimento urbano, a expansão de assentamentos rurais e a ampliação de áreas de agropecuária têm potencial para causar impactos profundos na biodiversidade, podendo aumentar o já preocupante estado de fragmentação da vegetação, causando isolamento entre populações, aumentando os riscos de extinção local. Foram levantadas as espécies ameaçadas, raras, endêmicas, de distribuição restrita no país, com problemas taxonômicos e prováveis espécies novas que ocorrem na região. The Urucum Mountains and its surroundings present unique characteristics in the Mato Grosso do Sul state and in Brazil, due to the influences this region receives from neighbor ecosystems, the endemism, and the occurrence in Brazil restrict to this area. The region represents a peninsula of non floodable terrain with 1,311 km2 that enters the Pantanal wetlands. In this narrow area, mining, industries, urban expansion, rural settlements, and increased agricultural areas potentially impact the biodiversity due to habitat destruction and fragmentation. We listed endemic species, as well as rare, endangered, restrictedly distributed, taxonomically unsolved, and potentially new species already known to the region

A Genome-Wide Analysis of Promoter-Mediated Phenotypic Noise in Escherichia coli

Gene expression is subject to random perturbations that lead to fluctuations in the rate of protein production. As a consequence, for any given protein, genetically identical organisms living in a constant environment will contain different amounts of that particular protein, resulting in different phenotypes. This phenomenon is known as “phenotypic noise.” In bacterial systems, previous studies have shown that, for specific genes, both transcriptional and translational processes affect phenotypic noise. Here, we focus on how the promoter regions of genes affect noise and ask whether levels of promoter-mediated noise are correlated with genes' functional attributes, using data for over 60% of all promoters in Escherichia coli. We find that essential genes and genes with a high degree of evolutionary conservation have promoters that confer low levels of noise. We also find that the level of noise cannot be attributed to the evolutionary time that different genes have spent in the genome of E. coli. In contrast to previous results in eukaryotes, we find no association between promoter-mediated noise and gene expression plasticity. These results are consistent with the hypothesis that, in bacteria, natural selection can act to reduce gene expression noise and that some of this noise is controlled through the sequence of the promoter region alon

Intervenções humanas na paisagem e nos habitats do Pantanal.

Neste documento, estão contidas algumas informações relevantes e de suma importância na preservação e conservação das paisagens e dos habitats do Pantanal. Essas informações foram obtidas através de levantamentos aéreos e viagens realizadas ao longo de 16 anos de trabalho na região. Neste trabalho, os autores listaram e descreveram, de forma clara e conceitual, os diferentes tipos de intervenções humanas na paisagem da planície pantaneira que, em algumas situações, ajudam a manutenção da fauna, mas podem, ao longo do tempo, se tornarem verdadeiras armadilhas. Esse trabalho contempla, dentre outros aspectos, a preocupação com o desmatamento de formações florestais e o aplainamento de murundus para a introdução de pasto cultivado. Apesar dessas intervenções, estudos recentes apontam que a planície está bem preservada com 85% de sua vegetação natural intacta, conferindo-lhe beleza e diversidade biológica. As informações contidas neste documento são um importante passo na formulação de políticas publicas voltadas para a preservação e conservação dos recursos naturais da região. Os autores chamam, ainda, a atenção para a necessidade de se estabelecer uma política de monitoramento dessas mudanças com vistas a garantir a sustentabilidade ecológica das atividades econômicas do Pantanal

Effect of severe versus moderate energy restriction on physical activity among postmenopausal female adults with obesity: a pre-specified secondary analysis of the TEMPO Diet randomized controlled Trial

BackgroundAn under-explored strategy for increasing physical activity is the dietary treatment of obesity, but empirical evidence is lacking.ObjectivesTo compare the effects of weight loss via severe versus moderate energy restriction on physical activity over 36 months.Methods101 postmenopausal female adults (45–65 years, 30–40 kg/m2, ResultsCompared to the moderate group, the severe group exhibited greater mean levels of: total volume of physical activity; duration of moderate-to-vigorous-intensity physical activity (MVPA); duration of light-intensity physical activity; and step counts, as well as lower mean duration of sedentary time. All these differences (except step counts) were apparent at 6 months (e.g., 1006 [95% confidence interval 564, 1449] MET-minutes per week for total volume of physical activity), and some were also apparent at 4 and/or 12 months. There were no differences between groups in the two other outcomes investigated (self-efficacy to regulate exercise; and proportion of participants meeting the World Health Organization's 2020 Physical Activity Guidelines for MVPA). When the analyses were adjusted for weight at each time point, the differences between groups were either attenuated or abolished.ConclusionsAmong female adults with obesity, including a dietary component to reduce excess body weight—notably one involving severe energy restriction—could potentially enhance the effectiveness of physical activity interventions