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Exploring the relationship between patterns of physical activity, sedentary behaviour and cardiometabolic health in middle-aged Irish adults
Get PDFBackground and Study Rationale Being physically active is a major contributor to both physical and mental health. More specifically, being physically active lowers risk of coronary heart disease, high blood pressure, stroke, metabolic syndrome (MetS), diabetes, certain cancers and depression, and increases cognitive function and wellbeing. The physiological mechanisms that occur in response to physical activity and the impact of total physical activity and sedentary behaviour on cardiometabolic health have been extensively studied. In contrast, limited data evaluating the specific effects of daily and weekly patterns of physical behaviour on cardiometabolic health exist. Additionally, no other study has examined interrelated patterns and minute-by-minute accumulation of physical behaviour throughout the day across week days in middle-aged adults. Study Aims The overarching aims of this thesis are firstly to describe patterns of behaviour throughout the day and week, and secondly to explore associations between these patterns and cardiometabolic health in a middle-aged population. The specific objectives are to: 1 Compare agreement between the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and GENEActiv accelerometer-derived moderate-to-vigorous (MVPA) activity and secondly to compare their associations with a range of cardiometabolic and inflammatory markers in middle-aged adults. 2 Determine a suitable monitoring frame needed to reliably capture weekly, accelerometer-measured, activity in our population. 3 Identify groups of participants who have similar weekly patterns of physical behaviour, and determine if underlying patterns of cardiometabolic profiles exist among these groups. 4 Explore the variation of physical behaviour throughout the day to identify whether daily patterns of physical behaviour vary by cardiometabolic health. Methods All results in this thesis are based on data from a subsample of the Mitchelstown Cohort; 475 (46.1% males; mean aged 59.7±5.5 years) middle-aged Irish adults. Subjective physical activity levels were assessed using the IPAQ-SF. Participants wore the wrist GENEActiv accelerometer for 7 consecutive days. Data was collected at 100Hz and summarised into a signal magnitude vector using 60s epochs. Each time interval was categorised based on validated cut-offs. Data on cardiometabolic and inflammatory markers was collected according to standard protocol. Cardiometabolic outcomes (obesity, diabetes, hypertension and MetS) were defined according to internationally recognised definitions by World Health Organisation (WHO) and Irish Diabetes Federation (IDF). Results The results of the first chapter suggest that the IPAQ-SF lacks the sensitivity to assess patterning of activity and guideline adherence and assessing the relationship with cardiometabolic and inflammatory markers. Furthermore, GENEActiv accelerometer-derived MVPA appears to be better at detecting relationships with cardiometabolic and inflammatory markers. The second chapter examined variations in day-to-day physical behaviour levels between- and within-subjects. The main findings were that Sunday differed from all other days in the week for sedentary behaviour and light activity and that a large within-subject variation across days of the week for vigorous activity exists. Our data indicate that six days of monitoring, four weekdays plus Saturday and Sunday, are required to reliably estimate weekly habitual activity in all activity intensities. In the next chapter, latent profile analysis of weekly, interrelated patterns of physical behaviour identified four distinct physical behaviour patterns; Sedentary Group (15.9%), Sedentary; Lower Activity Group (28%), Sedentary; Higher Activity Group (44.2%) and a Physically Active Group (11.9%). Overall the Sedentary Group had poorer outcomes, characterised by unfavourable cardiometabolic and inflammatory profiles. The remaining classes were characterised by healthier cardiometabolic profiles with lower sedentary behaviour levels. The final chapter, which aimed to compare daily cumulative patterns of minute-by-minute physical behaviour intensities across those with and without MetS, revealed significant differences in weekday and weekend day MVPA. In particular, those with MetS start accumulating MVPA later in the day and for a shorted day period. Conclusion In conclusion, the results of this thesis add to the evidence base regards an optimal monitoring period for physical behaviour measurement to accurately capture weekly physical behaviour patterns. In addition, the results highlight whether weekly and daily distribution of activity is associated with cardiometabolic health and inflammatory profiles. The key findings of this thesis demonstrate the importance of daily and weekly physical behaviour patterning of activity intensity in the context of cardiometabolic health risk. In addition, these findings highlight the importance of using physical behaviour patterns of free-living adults observed in a population-based study to inform and aid health promotion activity programmes and primary care prevention and treatment strategies and development of future tailored physical activity based interventions
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A protocol to measure the impact of intentional changes to nurse staffing and skill-mix in medical and surgical wards
Get PDFAim: The aim of this research is to measure the impact planned changes to nurse staffing and skill-mix have on patient, nurse and organisational outcomes. Background: It has been highlighted that there are several design limitations in studies that explore the relationship between nurse staffing and patient, nurse and organisational outcomes; not least that the vast majority of research in this area emanates from studies that are predominantly observational in design. There are limited studies that measure nurse, patient, organisational and economic outcomes using a longitudinal design following a planned change in nurse staffing. Design: The research will employ a longitudinal, multimethod approach to evaluate the impact that planned changes in nurse staffing and skill-mix have on wards in three pilot hospitals. Methods: Administrative data collection will take place on a shift-by-shift basis prospectively over a three-year period including the measurement of nursing sensitive outcomes: cross-sectional patient experience data and nurse outcomes (nursing work, job satisfaction, burnout, missed care) will be collected at intervals prior to, during and after the implementation of planned changes in nurse staffing and skill-mix. Data will be analysed using interrupted time series models, adjusted for key hospital, ward and patient-level factors. An economic costing of the changes will further investigate the resources required for the intervention that can then be aggregated to a national level for future roll-out plans. Discussion: The study aims to provide evidence on the impact of planned changes to nurse staffing and skill-mix based on a systematic approach using a longitudinal design and to determine the extent to which the approach can be implemented at a national level
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Sleep duration and fat mass during adolescence.
No full textIn the last years the influence of sleep duration on body composition has been widely studied. However, the findings are still inconclusive, especially those including adolescents. Thus, the aim of the present thesis was to conduct a systematic review on the influence of sleep duration on body composition, overweight and/or obesity in adolescents, to investigate factors associated with sleep duration in adolescence, and to assess the association between sleep duration trajectories from 11 to 18 years of age and body composition at 18 years. The study was conducted using data from the 1993 Pelotas Birth Cohort, in Brazil. At the age of 18, 4563 adolescents were located. Of these, 4106 were interviewed (follow-up rate 81.3%). In the analysis, 4085 and 3974 adolescents were included with complete data on sleep duration and body composition, respectively. Sleep duration was assessed by asking the adolescents the time they usually fall asleep and wake up on weekdays. Body composition (fat mass and fat-free mass) was obtained by air displacement plethysmography (BOD POD®). In both original papers we performed crude and adjusted analyzes using Linear Regression. We observed that longer sleep duration at 18 years of age was associated with perinatal variables (low maternal schooling, low family income, maternal black skin colour, and low birth weight) and those collected at 18-year follow-up (being out of school, low school achievement, low family income, absence of depressive symptoms, and high screen time). Regarding the influence of sleep duration trajectories on adolescent body composition, we found association among girls only. Girls who improved their sleep duration from 11 to 18 years of age showed an increase in body mass, fat mass, and fatfree mass indices compared to those who always had adequate sleep duration. These results suggest that social and demographic variables may play an important role in determining adolescents sleep duration. Also, they show gender differences in the relationship between sleep duration and body composition.Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqA influência do sono na composição corporal tem ganhado destaque na literatura nos últimos anos, porém os resultados dos estudos ainda são conflitantes e inconclusivos, especialmente, aqueles realizados com adolescentes. Assim, a presente tese teve como objetivo realizar uma revisão sistemática sobre a relação entre a duração do sono e composição corporal, sobrepeso e/ou obesidade de adolescentes, investigar os fatores associados com a duração do sono na adolescência e, por fim, avaliar a associação entre as trajetórias da duração do sono dos 11 aos 18 anos e a composição corporal aos 18 anos. Foram utilizados dados dos indivíduos pertencentes à Coorte de Nascimentos de 1993 de Pelotas, Brasil. Aos 18 anos de idade, foram localizados 4563 adolescentes; desses, 4106 foram entrevistados (taxa de acompanhamento de 81,3%). Foram incluídos nas análises, 4085 e 3974 adolescentes com dados completos de duração do sono e de composição corporal aos 18 anos de idade, respectivamente. A duração do sono foi avaliada através de questões sobre o horário que os adolescentes costumavam dormir e acordar em dias da semana. Já a composição corporal foi mensurada através de pletismografia por deslocamento de ar (BOD POD®), avaliando massa gorda e massa livre de gordura. Em ambos os artigos originais, foram realizadas análises brutas e ajustadas utilizando regressão linear. Observou-se que a maior duração do sono aos 18 anos esteve associada a variáveis perinatais (menor escolaridade materna, menor renda familiar, cor da pele negra, baixo peso ao nascer) e coletadas aos 18 anos (não estar estudando, menor escolaridade do adolescente, menor renda familiar, ausência de depressão e maior tempo de tela). Em relação à influência da trajetória da duração do sono na composição corporal dos adolescentes, observou-se que as meninas que passaram a ter duração adequada do sono dos 11 para os 18 anos apresentaram aumento dos índices de massa corporal, massa magra e massa livre de gordura, comparadas àquelas que sempre tiveram uma adequada duração do sono. Esses resultados sugerem que aspectos sociodemográficos desempenham importante papel na duração do sono dos adolescentes. Além disso, destacam diferenças da influência da duração do sono na composição corporal de acordo com o sexo
Influence of birth order and number of siblings on adolescent body composition.
No full textThe aims of the present study were to assess the influence of birth order and number of siblings on body composition in adolescents, and to evaluate the association between number of siblings and dietary patterns in adolescence. The study was conducted using data from the 1993 Pelotas Birth Cohort, in Brazil. At the age of 18 years, 4563 adolescents were located, of whom 4106 were interviewed (follow-up rate 81.3%). Of these, 3974 adolescents were included in our analysis with complete data on body composition and 3751 with data on dietary patterns. Body composition was assessed by fat mass index and fat-free mass index, both collected by air displacement plethysmography (BOD POD®). Principal component analysis was performed to identify dietary patterns. We identified four dietary patterns with a total variance of 40%, which we called ?Protein and fast foods?, ?Fruit and vegetables?, ?Sweets, soft drinks, and dairy products?, and ?Common Brazilian?. Crude and adjusted analyzes were performed using Linear Regression. A systematic review and metaanalysis were also performed. The objective was to examine the effects of birth order and number of siblings on overweight/obesity. Our findings showed that the number of siblings was the key influence on body composition, rather than the position that the adolescents occupy amongst siblings. Only children of both sexes were more likely to have higher fat mass index compared to those who have siblings. Girls who have no siblings presented the lowest levels of fat-free mass while boys without siblings had greater body mass index. Also, adolescents with a higher number of siblings had a higher adherence to ?Protein and fast foods?, ?Fruit and vegetables?, and ?Sweets, soft drinks, and dairy products? patterns. In conclusion, our results showed that the number of siblings influences both body composition and dietary patterns of adolescents. Higher number of siblings was associated to a more diverse diet among the adolescents, higher fat-free mass index, and lower body mass and fat mass indices. Thus, the research highlights the need for intervention programs focusing on adolescents who are only children.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESO presente trabalho teve como objetivos avaliar a influência da ordem de nascimento e do número de irmãos na composição corporal de adolescentes, e avaliar a associação entre número de irmãos e padrões alimentares na adolescência. Foram utilizados dados da Coorte de Nascimentos de 1993 de Pelotas, Brasil. Aos 18 anos de idade, dos 4563 adolescentes localizados, 4106 foram entrevistados (taxa de acompanhamento de 81,3%). Dentre eles, 3974 foram incluídos nas análises com dados completos de composição corporal e 3751 com dados de padrões alimentares. A composição corporal foi avaliada através do índice de massa gorda e do índice de massa livre de gordura, ambos coletados através de pletismografia por deslocamento de ar (BOD POD®). Para identificar os padrões alimentares, análise de componentes principais foi realizada. Quatro padrões alimentares foram identificados com variância total de 40%: ?Proteína e fast foods?, ?Frutas e vegetais?, ?Doces, refrigerantes e produtos lácteos? e ?Comum brasileiro?. Análises brutas e ajustadas foram realizadas utilizando regressão linear. Também foi realizada uma revisão sistemática e meta-análise, cujo objetivo foi examinar os efeitos da ordem de nascimento e do número de irmãos sobre o sobrepeso/obesidade. Os resultados mostram que o número de irmãos, e não a ordem de nascimento, teve maior influência sobre a composição corporal dos adolescentes. Os filhos únicos de ambos os sexos têm maior índice de massa gorda comparados àqueles que têm irmãos. Meninas filhas únicas apresentaram menor índice de massa livre de gordura, enquanto os meninos tiveram maior índice de massa corporal. Além disso, adolescentes com maior número de irmãos tiveram maior adesão aos padrões ?Proteína e fast foods?, ?Frutas e vegetais? e ?Doces, refrigerantes e produtos lácteos?. Pode-se concluir que o número de irmãos influencia tanto a composição corporal quanto os padrões alimentares dos adolescentes. Maior número de irmãos na adolescência esteve associado à maior diversidade na dieta e maior índice de massa livre de gordura, além de menores índices de massa corporal e massa gorda. Diante disso, destaca-se a necessidade de programas de intervenção focados nos adolescentes filhos únicos
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