Medidas antropométricas e de composição corporal como preditoras de alterações da pressão arterial em adultos

• Autor(a) principal: Oliveira, Josie de Souza
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2736
• topic: Pressão arterial; Composição corporal; Indicadores antropométricos; Blood pressure; Body composition; Anthropometric indicators; CNPQ::CIENCIAS DA SAUDE::NUTRICAO

This study aimed to evaluate the ability of anthropometric indicators and body composition in predicting of blood pressure disturbance in adults in Viçosa, MG, and check the agreement between methods of assessing body composition. Was conducted cross-sectional study, whose sample consisted of 161 volunteers of both sexes, aged between 20 and 59 years. Anthropometric measures included weight, height, waist circumference (WC), hip and thigh and sagittal abdominal diameter (SAD). We calculated the waist-hip ratio (WHR), waist / height (WHtR) and waist / thigh (WTR) and conicity index (CI), the abdominal diameter (ADI) and body mass index (BMI). To check the total body fat percentage (%TBF) was used the tetrapolar bioelectrical impedance analysis (BIA). To compare the predictive methods of body fat (bipolar bioelectrical impedance (Tanita ®) and the equations of body fat estimates proposed by Deuremberg et al. (1991), Gallagher et al. (2000) and Lean et al. (1996)) was used BIA as the reference method. The blood pressure (BP) was measured using a sphygmomanometer, considering as BP disturbance the 75th percentile as the cut-off point. Statistical analysis was performed using the intraclass correlation analysis, analysis of variance with Tukey post-hoc test, the Kruskal-Wallis test with post hoc Dunn's, the correlation coefficients of Spearman and Pearson construction of ROC curves (Receiver Operating Characteristic Curve) and the analysis of Bland-Altman agreement. We identified 32.3% and 43.5% of men with disturbance SBP and DBP, respectively, and 37.4% and 43.4% of women with SBP and DBP above the 75th percentile, respectively. It was found that people with BP disturbance have WC and SAD significantly higher than the desirable BP. The WC measured at lower waist differed significantly from other locations evaluated (p<0.001) in females, although male was lower (p<0.05) than the waist measured at the midpoint. The SAD did not differ in any of the measures for both sexes. All measures of the WC and the SAD showed very high reproducibility (0,999-1,000). The correlations presented by the WC and the SAD were moderate, except the WC in relation to SBP in males, which correlation was weak (r=0.298). It was found that there was no significant difference between the areas under the curve for the WC and the SAD in the prediction of BP disturbance in individuals of both sexes. The nine evaluated indicators of obesity were able to predict disturbance in BP. In agreement with the correlation analysis, the SAD was the indicator that showed the greatest predictive capacity of SBP and DBP in the male population, whose cut-off points were 18.5 cm and 18.4 cm, respectively. Although in the female is also consistent with the correlation analysis, the indicators that showed the highest discriminatory power of SBP and DBP, respectively, were the ADI and %TBF, and the best cut-off values 0.36 and 29.8%. On the diagnosis of obesity was observed that, according to BMI, 9.9% of patients had obesity. However, 28.6% of the population studied, had higher percentage of fat, framing them in the obese group. Among the methods tested in the male population, the equation of Gallagher et al. (2000) was the only one that did not show statistical difference when compared to the BIA, although in the female, all equations were significantly different. For men, the Tanita® and the equation of Gallagher et al. (2000) were the methods that showed better agreement. However, the Tanita® and all the studied equations significantly overestimated the %TBF of women and none of the methods presented SEE<3.5%. Judging by the results, it is assumed that not only indicators of abdominal adiposity, but also markers of general obesity have practical applicability in the prediction of elevated blood pressure levels. It should be noted, therefore, the importance of using obesity indicators, whether abdominal or general, over the use of BMI alone for two main reasons - first, for this indicator having less efficiency in predicting disturbance in blood pressure levels when compared to the above mentioned and, second, because it erroneously classified as normal subjects with %TBF high enough to classify them as obese. It was observed that the use of inappropriate methods or equations of the type of population to be evaluated can affect the tracking of overweight and correct diagnosis of obesity. Based on the knowledge of disturbance in blood pressure caused by obesity, aware that individuals with blood pressure levels higher than considered desirable have the same pathophysiology of those with hypertension and that these individuals have a greater chance of developing such morbidity, we think it is necessary to use indicators and accurate cut-off points in order to early detect individuals predisposed to develop pre-hypertension. Thus, chronic diseases such as hypertension can be prevented, or at least delayed.