published_or_final_version / Community Medicine / Master / Master of Philosophy

Objectives: In recent decades, obesity reached epidemic proportions in western countries, while cigarette smoking decreased. Traditionally, smoking is associated with lower relative weight (body mass index, BMI) but high abdominal obesity (waist-hip ratio, WHR). However, several recent studies suggest that BMI is higher among today’s smokers compared with non-smokers. Therefore, the present study examined whether the relationship between smoking and each of the body measures, BMI and WHR, has changed over time. Material and Methods: Data were collected from 5907 male and female residents of Gothenburg, Sweden, aged 25-65 years, and drawn randomly in four sequential cross-sections (1985, 1990, 1995, 2002) from the city’s population register. The study used general linear models to test trends over time, and adjusted all differences for age. Results: The data reported here showed higher WHR in both male and female smokers compared with non-smokers. BMI was lower in female smokers compared with female non-smokers, but did not differ significantly between male smokers and male non-smokers. Among female participants, differences in WHR between smokers and non-smokers increased significantly throughout the study. Although male participants showed a similar tendency, the differences were not significant. Adjustment for educational level did not affect the results. Conclusions: WHR was higher among smokers compared with non-smokers; this difference increased over time. Thus, concern for obesity does not provide a valid reason to continue smoking; on the contrary, it may be a reason to quit. / <p>ISBN 978-91-86739-06-5</p>

The primary objective of the work presented in this thesis was to identify trends in maternal body mass index (BMI) over time, the demographic predictors of those women most at risk of being obese in pregnancy, health inequalities, and the impact of maternal obesity on maternity services. A mixed methodology utilised quantitative and qualitative research to address these objectives. Data were collated from 34 maternity units across England, including 619,323 deliveries between 1989 and 2007 inclusive. Analysis identified an increasing incidence of maternal obesity over time, regional differences in incidence, and significant inequalities with women residing in the highest levels of deprivation, and Black ethnic group. A systematic review was carried out including 49 studies investigating obesity and pregnancy outcomes with acute maternity resource implications. The meta-analysis found significantly increased odds of a number of outcomes, and concluded that maternal obesity had a considerable impact on maternity resources, and contributed towards a poorer prognosis for the mother and the baby during delivery and in the immediate post-partum period. Qualitative interviews and focus groups with 30 HCPs across eight NHS Trusts in the North East of England were carried out to identify barriers in implementing maternal obesity services, and to gain HCPs perspectives on what they felt was required in order to address maternal obesity effectively. The study identified the themes of ‘Service Development’, ‘Psychosocial Issues and Maternal Obesity Services’, ‘Information, Evidence, and Training’, and ‘Where to go From Here?’. Overall this programme of research has identified that maternal obesity is increasing over time and is significantly associated with health inequalities. The increase in maternal obesity has an impact on acute services, and HCPs feel that a holistic approach is required through partnership work in order to address maternal obesity effectively. This programme of research has primarily contributed to the knowledge of maternal obesity with the provision of the first national level statistics for trends in maternal obesity. The research has also provided a holistic view of the impact of obesity in pregnancy on maternity services, including the impact on resources and the issues relating to addressing the maternal obesity in clinical practice. The research has also identified aspects of service that need to be improved, and knowledge gaps in how to move services forward to effective address maternal obesity. The contribution of this research to the knowledge base is emphasised in the journal pre-publications, dissemination through UK and European, and international conference presentations, being an invited speaker at a number of conferences in the UK, and I received the 2007 Association for the Study of Obesity (ASO) Student Researcher Award for producing exemplary work in the study of obesity.

The aims of the present study were to investigate the association between overweight and cognitive ability and dementia, and to evaluate the usefulness of self-reported body mass index (BMI) in late life and various data sources commonly used in epidemiological studies to identify persons with dementia. Data were drawn from three population-based studies: the Swedish Adoption/Twin Study of Aging (SATSA), Aging in Women and Men: A Longitudinal Study of Gender Differences in Health Behaviour and Health among Elderly (the Gender Study), and the Finnish Lieto Study. In Study I, the agreement between self-reported and measured BMI over time was evaluated among 774 men and women, ages 40 to 88 years at baseline (mean age 63.9) participating in both the questionnaire phase and in-person testing of SATSA. Latent growth curve (LGC) modeling showed a small but significant increase between self-reported and measured BMI (0.02 kg/m2/y) over time, which would probably not affect the results if self-reported BMI were used as a continuous variable in longitudinal research. In Study II, the agreement between dementia diagnoses from various sources and dementia diagnoses set at a consensus conference was evaluated. Among the 498 elderly people ages 70 to 81 at baseline (mean age 74.5) enrolled in the Gender Study, 87 were diagnosed with dementia during an eight-year period. Review of medical records and nurse evaluations yielded the highest sensitivity (0.83 and 0.80, respectively) and a high specificity (0.98 and 0.96), indicating that these sources might be good proxies of dementia, while data extraction from the Swedish Inpatient Discharge Registry underestimated the prevalence of dementia (sensitivity 0.26). In Study III, the association between being overweight in midlife and cognitive ability in late life was examined in SATSA. The 781 participants ages 25 to 63 at baseline (mean age 41.6) in 1963 or 1973 self-reported their height and weight. From 1986 until 2002, they were assessed five times using a cognitive test battery. LGC models showed that people with higher midlife BMI scores had significantly lower cognitive ability and a significantly steeper decline than their thinner counterparts, an association that persisted when those who developed dementia during the study period were excluded from the analysis. This finding indicates that being overweight might affect cognitive ability independently of dementia. In Study IV, the association between BMI and dementia risk in older persons was described among 605 persons without dementia and ages 65 to 92 at baseline (mean age 70.8) in the Lieto Study. Among these, 86 persons were diagnosed with dementia during eight years of follow-up. Cox regression analyses indicated that for each unit increase in BMI score, the risk of dementia decreased 8% (hazard ratio = 0.92, 95% confidence interval = 0.87–0.97) and the association remained significant when individuals who developed dementia during the first four years of follow-up were excluded from the analyses. This result suggests that low BMI scores are present almost a decade before clinical dementia onset.

ABSTRACT The Implications of Chronic Stress on Obesity: Allostatic Load on Body Mass Index (BMI) Classification in the United States, NHANES 2005-2006 INTRODUCTION: In this modern environment, our world is reflecting an exponential increase in not only population, but in body size. Obesity is an overwhelming public health concern among the United States population. Research has shown there is a positive correlation between adiposity and stress. Allostatic load (AL) has been presented to be a consistent measure of chronic stress damage on the body. Yet, there is few studies exemplifying the presence AL on classification of body mass index (BMI). AIM: The aim of this study is to find a relationship between allostatic load (AL) and body mass index (BMI) classification in the United States adult population on a large national scale. This complex interaction can predetermine who among the US population will be at greater risk for excess adiposity following this psychoneuroendocrinology. METHODS: A representative sample size of n=3826 was gathered using NHANES data (2005-2006). Criteria for sample included all United States adults that had numerical values for 10 biomarkers chosen to represent chronic stress damage (allostatic load) along with individual body mass index (BMI). Allostatic load (low, high) and BMI classification (underweight to class III obese) were further categorized on severity and computed in SPSS to find significance between gradients of each variable (α=.05). Cross-sectional analysis and logistical regression (multivariate) were used to further decipher an association between allostatic load and BMI category. RESULTS: A strong positive correlation between allostatic load risk and BMI category was found (p<.001). Also among the variables in the study, significance was found within the strata of age, gender, race, smoking status and poverty income ratio (PIR). Findings show a strong statistically significant relationship between allostatic load and BMI. DISCUSSION: It is imperative to decipher the directional relationship between stress and obesity to provide effective treatment. Understanding the pathology of how stress affects adiposity could open the door for many clinical and public health interventions to eradicate a very preventable outcome. By addressing the effect of chronic stress, a new avenue of prevention can be developed to combat the growing obesity rates in the United States.

The population of the United States is increasingly gaining weight each year.Americans are heavier than they have ever been. African American women are at the forefront of this pandemic. This study addresses the higher prevalence of overweight and obesity among African American women in comparison to White women. Behavioral, psychological, and social known contributors to overweight and obesity using the National Health Interview Survey, 2001 dataset were examined in this study. The research concluded that even when controlling for vigorous exercise, education, income, depression, emotional support, smoking, health coverage, and age, race is the most important predictor of body mass index. Consistent with previous studies, strong race effects still remained.

Introdução No Brasil a obesidade é um importante problema de saúde pública com prevalência mais elevada em mulheres do que em homens. A gestação e o período pós-parto são momentos críticos devido à ocorrência de ganho ponderal excessivo na gravidez e retenção de peso pós-parto. Objetivos Estudar a influência da paridade sobre o IMC em mulheres brasileiras com idade entre 20 e 49 anos .Investigar o possível efeito de modificação do poder aquisitivo,escolaridade e utilização do SUS sobre a associação entre paridade e IMC. Métodos Foram analisados dados da Pesquisa Nacional de Demografia e Saúde 2006, inquérito que utilizou amostragem complexa representativa de todo o território brasileiro. A associação entre o fator de estudo (paridade: 0,1,2, 3 e + ) e o desfecho (IMC) foi testada mediante análise de regressão linear. O efeito ajustado do fator de estudo sobre o IMC foi avaliado em modelo múltiplo contendo como variáveis de controle: idade, classes de poder aquisitivo ABEP (A+B1, B2+C+D e E), e escolaridade (<8 e 8 anos de estudo completo). Para testar as interações de interesse foram realizados modelos múltiplos, em separado,incluindo três variáveis que combinam paridade dicotômica (nulíparas e demais) com poder aquisitivo,escolaridade e utilização do SUS.Foram considerados significativos valores de p inferiores a 0,05. Resultados Das 13.087 mulheres investigadas foram excluídas do estudo 14,4 % (gestantes, mulheres com filhos menores de 6 meses e aquelas com dados incompletos para peso e altura). A análise foi conduzida em uma amostra de 11.961 mulheres, levando-se em consideração a estrutura complexa da amostra. A média de IMC para o conjunto das mulheres brasileiras foi de 25,6 Kg/m2 (IC95%: 25,4 - 25,8). O IMC médio foi maior entre as pertencentes à classe de poder aquisitivo intermediária (B2,C,D) e baixa (E). Observou-se elevação do IMC com o aumento do número de filhos e idade. Na análise ajustada,confirmou-se a associação positiva entre paridade e IMC (p de tendência < 0,001). Dentre as interações testadas foi estatisticamente significativa a existente entre poder aquisitivo,paridade e IMC. As mulheres com um filho ou mais pertencentes à classe intermediária de poder aquisitivo quando comparadas às nulíparas da classe alta, apresentaram um incremento de 1,40 unidades de IMC (IC95% : 0,64 2,19 p < 0,001 ). Nas demais classes (A+B1) e (E) não foi detectada associação estatisticamente significativa entre paridade e IMC.Conclusões Nas mulheres brasileiras,a paridade exerce influência positiva sobre o IMC após controle de variáveis de confundimento. Detectou-se interação entre poder aquisitivo, paridade e IMC: o efeito da paridade é estatisticamente significativo apenas nas mulheres da classe intermediária de poder aquisitivo (B2,C eD). / Introduction - In Brazil, obesity is a public health problem and its prevalence is higher among women. Pregnancy and the postpartum period are critical moments for the occurrence of excessive weight gain and weight retention. Objectives - To study the influence of parity on BMI in Brazilian women aged between 20 and 49 years. To investigate the possible modifying effect of the purchasing power, schooling and the use of public health system in the relation between parity and BMI. Methods - We used data from the National Demographic and Health Survey 2006, a survey with a complex sample, nationally representative of the Brazilian territory. The association between the study factor (parity: 0,1,2, and 3 +) and the outcome (BMI) was tested by linear regression analysis. The effect of parity on BMI was evaluated by a multivariate model adjusted by control variables: age, score ABEP (A + B1, B2 + C + D and E) and education (<8 and 8 years of study). To test the interactions, multivariate models were performed in separate with three different variables combining parity (nulliparous and others) with purchasing power, education and use of the public health system. The level of significance adopted was p < 0,05. Results - From the 13.087 women screened, 14,4% were excluded (pregnant women, women with children under 6 months and those with incomplete data for height and weight). The analysis was conducted on a sample of 11.961 women, adjusted by the complex structure. The mean BMI of the Brazilian women was 25,6 kg/m2 (95% CI: 25,4 to 25,8). It was higher among women in the middle class purchasing power (B2, C, D) and in the lower class (E). The BMI was elevated with the increase of parity and age. In adjusted analysis, the positive association of parity on BMI was confirmed (p trend <0,001). There was a statistically significant interaction among purchasing power, parity and BMI. When compared to nulliparous upper class women, those with one or more children in the middle class had an increase of 1,40 BMI units (95% CI: 0,64 to 2,19 p <0,001). Among the other purchasing classes (A + B1) and (E) there wasnt significant association between parity and BMI. Conclusion In the Brazilian women, parity influences positively the mean BMI, after adjustment for confounding variables. An interaction was detected among purchasing power, parity and BMI: the effect of parity is statistically significant only in women from the middle class (B2, C and D).

Background: The prevalence of anxiety postpartum is high. Physical activity has shown positive effects for depressive symptoms and anxiety in pregnant women. The risk of anxiety postpartum can increase with a high and low Body Mass Index (BMI), no studies have been found to investigate the correlation between muscle mass and anxiety. Aim: To investigate the correlation between level of anxiety, BMI and proportion of muscle mass postpartum and see if there were any differences in level of self-reported anxiety between two independents groups: those who reported regular exercise and those who didn’t report regular exercise during pregnancy. Method: A quantitative correlative and comparative cross-sectional study. Data was collected using Beck Anxiety Inventory (BAI) questionnaire and one question about training answered by 2599 participants. Bioimpedance was used to calculate the proportion of muscle mass and BMI and included 164 participants. Results: There was a correlation between higher level of anxiety and higher proportion of muscle mass (r=0.25 p=&lt;0.05) and between higher level of anxiety and higher BMI (r=0.23 p=&lt;0.05). There was a difference (p=&lt;0.05) in level of anxiety between two groups: those who reported regular exercise: Md 4 (Q=6) self-reported a lower level of anxiety than those who didn´t report regular exercise: Md 4 (Q=8). Conclusion: High BMI and high proportion of muscle mass correlate with higher level of anxiety postpartum. There was a correlation between exercise during pregnancy and a decreased level of anxiety.

Introdução: A associação entre tuberculose (TB) e desnutrição é bem reconhecida: a TB pode levar à desnutrição e a desnutrição pode predispor à TB. Levando-se em consideração o risco de mortalidade devido à desnutrição em pacientes com TB e as inúmeras limitações dos estudos realizados até hoje, é necessário realizar uma avaliação nutricional mais completa e precoce com o objetivo de identificar os indivíduos em risco nutricional. Objetivos: Avaliar o estado nutricional dos pacientes hospitalizados com TB, coinfectados ou não pelo vírus da imunodeficiência humana (HIV). Métodos: Estudo de prevalência com coleta de dados prospectiva. Foram incluídos pacientes com diagnóstico confirmado de TB. Foram utilizados os seguintes métodos para avaliação nutricional: índice de massa corporal (IMC), dobras cutâneas, bioimpedância, circunferência do braço (CB), circunferência muscular do braço (CMB), questionário de frequência alimentar, ferramenta de triagem de desnutrição (MST), avaliação subjetiva global (ASG) e dosagens de hemoglobina, transferrina, proteína C reativa, albumina e linfócitos. Resultados: Foram incluídos 92 pacientes no estudo. Considerando o IMC, 37% dos pacientes avaliados apresentavam critérios para risco nutricional. O percentual de gordura corporal foi baixo em 31,5% dos pacientes. Além disso, mais da metade dos indivíduos estudados apresentou critérios para desnutrição conforme a CB, CMB, dobra cutânea tricipital, ASG, MST ou parâmetros laboratoriais. Com relação aos nutrientes da dieta, em pacientes HIV positivos a ingestão de selênio foi significativamente menor do que nos pacientes HIV negativos. Também foram encontradas correlações positivas entre o IMC e a quantidade de zinco e magnésio da dieta. Conclusões: Identificamos uma prevalência elevada de desnutrição em pacientes com TB pulmonar internados em um hospital terciário, independente do método utilizado para avaliação do estado nutricional. / Introduction: The association between tuberculosis (TB) and malnutrition is well recognized: TB can lead to malnutrition and malnutrition can predispose to TB. Taking into account the risk of mortality due to malnutrition in patients with TB and the numerous limitations of the studies conducted to date, it is necessary to conduct a more thorough and early nutritional assessment in order to identify individuals at nutritional risk. Objectives: To assess the nutritional status of hospitalized patients with TB, co-infected or not by the human immunodeficiency virus (HIV). Methods: Prevalence study with prospective data collection. Patients with confirmed diagnosis of TB. The following methods of nutritional assessment were used: body mass index (BMI), skinfold thickness, bioelectrical impedance, arm circumference (AC), arm muscle circumference (AMC), food frequency questionnaire, malnutrition screening tool (MST), subjective global assessment (SGA) and serum levels of hemoglobin, transferrin, C-reactive protein, albumin and lymphocytes. Results: We included 92 patients in the study. Considering the BMI, 37% of the patients met the criteria for nutritional risk. The body fat percentage was low in 31.5% of patients. In addition, more than half of the subjects met criteria for malnutrition according to AC, AMC, triceps skinfold thickness, SGA, MST or laboratory parameters. Regarding the components of diet, selenium intake among HIV-positive patients was significantly lower than in HIV-negative patients. It was also found positive correlations between the BMI and the amount of dietary zinc and magnesium. Conclusions: We identified a high prevalence of malnutrition in patients with pulmonary TB admitted in a tertiary hospital, regardless of the method used to assess nutritional status.

O índice de massa corporal (IMC) é o resultado do cálculo que relaciona o peso com a altura, é amplamente utilizado para classificar os diferentes níveis do estado nutricional em adultos e é citado como um fator de previsão da dificuldade da cirurgia de terceiros molares. A capacidade de abertura da boca, o posicionamento da bochecha e da língua são aspectos comumente relacionados com a dificuldade cirúrgica por interferirem diretamente com a capacidade de observação do campo cirúrgico. Partindo do pressuposto que o IMC pode estar relacionado com estas variáveis anatômicas locais, este estudo correlacionou as medidas destes aspectos anatômicos com o IMC tendo como objetivo verificar se existe alguma relação e como ela se expressa. Foram avaliados 91 sujeitos, sendo 35 do gênero masculino e 56 do gênero feminino, com idades variando entre 18 e 48 anos. O IMC médio das mulheres foi de 22,23 kg/m2 e dos homens, de 25,82 kg/m2. A análise estatística mostrou haver uma associação positiva com diferença significante do IMC com a abertura de boca. O IMC mostrou uma tendência à associação com o posicionamento da bochecha e não mostrou relação com a profundidade da cavidade oral ou posicionamento da língua. Como não existe uma escala efetiva de previsão da dificuldade cirúrgica para exodontia de terceiros molares, o IMC é um fator que também deve ser considerado neste planejamento cirúrgico, pois representa um dado preditivo válido, o qual além de suas repercussões sistêmicas, também interfere de maneira local em cirurgias de terceiros molares, portanto, sua consideração na análise preditiva da dificuldade cirúrgica soma valores de segurança ao ato cirúrgico. / The body mass index (BMI) is the result of the calculation that relates weight to height, is widely used to classify the different levels of nutritional status in adults and is cited as a factor in predicting the difficulty of third molar surgery. The ability to open the mouth, the positioning of the cheek and tongue are aspects commonly associated with surgical difficulty by directly interfering with the ability of observation of the surgical field. Assuming that BMI may be related to these variables anatomical , this study correlated the measures of these anatomical features with BMI aiming to verify whether there is any relationship and how it is expressed. We evaluated 91 subjects, 35 males and 56 females, aged between 18 and 48 years. The average women BMI was 22.23 kg/m2 and the average men BMI was 25.82 kg/m2. Statistical analysis showed a positive association with a significant difference in BMI with the mouth opening. BMI showed a trend toward association with the positioning of cheek and was not related to the depth of the oral cavity or tongue positioning. As there is no effective scale prediction of surgical difficulty for extraction of third molars, BMI is a factor that should also be considered in this surgical planning. It represents a valid predictive factor that interferes in third molar surgery. The BMI consideration in predictive analysis of surgical difficulty adds security values to oral surgery.