Background Excess adipose tissue and low physical activity are two major determinants for chronic diseases such as type 2 diabetes and cardiovascular disease.  Understanding these relationships requires accurate and precise measures of body composition and physical activity, and most existing observational studies lack such measures. Paper I to III in this thesis addresses the validity of measures of physical activity and abdominal adipose mass. In paper IV and V, we explore the relationships between obesity and physical activity on metabolic health in non-pregnant and pregnant women and their offspring. Methods and Results Two hundred men and women representative of the Northern Sweden EPIC cohort were recruited for Paper I. A questionnaire on physical activity (PAQ) was validated against objectively measured physical activity energy expenditure (PAEE). A categorical physical activity index (Cambridge index) calculated from PAQ showed strongest correlation with PAEE (r=0.33 p<0.05). In Paper II, abdominal adiposity were assessed in 29 adult men and women using anthropometric measurements, dual energy x-ray absorptiometry (DXA) and ultrasound and were compared to computed tomography (CT). Waist circumference showed the highest correlation with CT-assessed visceral (r=0.85, p<0.0001) and subcutaneous adipose tissue (r=0.86, p<0.0001). Adipose thickness was best assessed with ultrasound. In Paper III, the validity of a wrist-worn triaxial accelerometer was assessed in 32 pregnant and 74 non-pregnant women using double-labeled water method (DLW) as the criterion measure. The output from the accelerometer explained 24% (p <0.001) of the variation in PAEE in non-pregnant and 11% (p<0.05) in the pregnant women. In Paper IV, 35 pregnant and 73 non-pregnant women underwent a 75g oral glucose tolerance test and habitual energy expenditure and physical activity was assessed objectively. Total physical activity was inversely associated with early insulin response in both pregnant (r=-0.47, p=0.007) and non-pregnant (r=-0.36, p=0.004) women. In, Paper V, 32 women and their offspring (n=33) were studied 4 months post-partum. Body composition was quantified using DXA in the women and air-displacement plethysmography  in the infants. Mid-pregnancy weight gain was significantly associated with infant fat mass (r=0.41, p=0.022), whereas late-pregnancy weight gain associated to infant fat-free mass (r=0.37, p=0.04). Conclusion This work describes new methods as well as conventional anthropometric estimates and a questionnaire, that provide relatively strong estimates of body composition and physical activity which could be used in larger studies. Pregnant women were shown to have more sedentary behavior than non-pregnant but physical activity appeared to have equal effect on glucose homeostasis in both groups, which may help guide lifestyle interventions in pregnancy. The impact of weight gain during the different trimesters seems to differentially affect the offspring’s body composition in early infancy, which might give us clues to when different aspects of fetal development and growth occur and how modifiable lifestyle behaviors might be intervened upon to improve long-term health. / Embargo

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-11-27T19:08:40Z No. of bitstreams: 1 Eloina Nunes de Oliveira Validacao da ultra... 2002.pdf: 56743053 bytes, checksum: 8de974eee276ef14038c01e971d6e751 (MD5) / Made available in DSpace on 2012-11-27T19:08:40Z (GMT). No. of bitstreams: 1 Eloina Nunes de Oliveira Validacao da ultra... 2002.pdf: 56743053 bytes, checksum: 8de974eee276ef14038c01e971d6e751 (MD5) Previous issue date: 2002 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / Como fator de risco cardiovascular, a distribuição de gordura corporal é provavelmente mais significante do que o aumento de peso por si só. A quantificação de adiposidade visceral é de grande valor, pois esse tecido tem um papel importante em agregar os fatores de risco metabólicos. 0 padrão ouro para avaliação quantitativa da adiposidade visceral é a Tomografia Computadorizada (TC). 0 uso dessa técnica na pesquisa de gordura visceral é limitado devido ao equipamento necessário, alto custo e exposição à radiação ionizante. Em estudos clínicos e epidemiológicos a medida da cintura é estimativa mais freqüentemente usada para gordura abdominal visceral. Apesar dessa medida mostrar uma boa correlação com a medida de gordura abdominal visceral pela TC, ela é menos precisa e fortemente associada com índice de massa corpórea. A ultra-sonografia (LIS) tem sido proposta como uma técnica não invasiva, de baixo custo, para avaliação de gordura abdominal visceral. Objetivos: Validação do uso da ultra-sonografia na determinação de gordura abdominal em pacientes coronariopatas. Material e Métodos: Neste estudo observacional foram determinadas as espessuras abdominais subcutâneas e viscerais através da ultra-sonografia e áreas abdominais subcutâneas e viscerais pela TC, em uma população de coronariopatas e dislipidêmicos, constituída de 28,3% de mulheres e 71,1% de homens, idade média de 56,8 anos (32-81 anos), encaminhada pelo ambulatório de cardiopatia isquémica e dislipidemia (ACID) do Hospital Universitário Professor Edgar Santos (HUPES). Todos os pacientes foram submetidos a exame clínico, medidas antropométricas, US e TC. Resultados: A espessura abdominal visceral, medida pela US, mostrou correlação positiva significativa com área abdominal visceral pela TC (r = 0,73; p < 0,0001). Para a predição da área visceral pela TC foi realizada análise de regressão múltipla sendo que as variáveis de maior correlação foram compostas pelas medidas de espessura abdominal visceral, a medida da cintura e idade (r^ = 0,69; p < 0,001). Conclusões: Em coronariopatas e dislipidêmicos a US mostrou-se método válido na determinação de gordura abdominal visceral. É possível determinar através da US a área de gordura abdominal visceral com grau de determinação de quase 70%. / Fat distribution is probably more significant tlian weight increase per se as a cardiovascular risk factor. Because visceral adiposity has a central role in the cluster of metabolic risk factors, its quantification is of extreme importance. Currently, Computed Tomography (CT) is the gold standard for quantitative assessment of intra-abdominal adipose tissue. This technique is obviously limited because of high cost and radiation exposure. In clinical and epidemiological studies the waist circumference is the most often used estimation of intra-abdominal adipose tissue. Although, this measure shows a good correlation with CT-measured intra-abdominal adipose tissue, it is less precise and less strongly associated with body mass index. Ultrasonography has been proposed as a noninvasive technique to accurately measure intra- abdominal adipose tissue. Objective: Validity of use of ultrasonography for 11 the determination of abdominal adipose tissue in patient with coronary heart disease. Material and Methods: This observational study was carried out among 60 patients with coronary heart disease and dyslipidemia. Subcutaneous and intra-abdominal adipose tissue thickness were measured by ultrasonography, and subcutaneous and intra-abdominal adipose tissue areas by CT. All patients were submitted to clinical examination, anthropometry, ultrasonography and CT evaluation. Results: The mean age of the study group was of 56,8 ± 10,2, the sex distribution was of 28,3% women and 71,1% men. The thickness of intra-abdominal adipose tissue measured by ultrasonography showed significant positive correlation with intra-abdominal adipose tissue area by CT (r = 0,73; p <0,000). Multiple regression analysis was applied for the prediction of intra-abdominal area by CT. The variables of better correlation were composed of the measures of intra-abdominal adipose tissue thickness, the measure of the waist circumference and age (r^ = 0,69; p <0,001). The area under the Receiver Operating Characteristic Curve (ROC) was 0,81 (IC95% de 0,68-0,95). Conclusions: In patients with coronary heart disease, ultrasonography is a good method to diagnose and to determine intra-abdominal adipose tissue. It is possible to determine through ultrasonography and anthropometry, the area of intra-abdominal tissue with a degree of precision of almost 70%.