Validade da massa corporal e da estatura autorreferidas: relações com sexo, idade, atividade física e fatores de risco cardiometabólicos / Validity of self-reported body mass and height: relation with sex, age, physical activity, and cardiometabolic risk factors

RESUMO: Objetivo: Avaliar a validade da massa corporal e da estatura autorreferidas em adolescentes, adultos e idosos segundo sexo, idade, nível de atividade física no lazer, estado nutricional e fatores de risco cardiometabólicos. Métodos: Participaram do estudo 856 sujeitos, com 12 anos ou mais, que responderam ao Inquérito de Saúde de São Paulo (ISA-2015) e que possuíam a massa corporal e a estatura autorreferidas e aferidas. Com base no índice de massa corporal, realizou-se uma classificação do estado nutricional de acordo com critérios padronizados para cada fase da vida. A validade das medidas autorreferidas foi examinada usando o coeficiente de correlação intraclasse, Bland-Altman e o teste t pareado. Utilizaram-se regressões lineares para elaborar os coeficientes de calibração, e realizaram-se testes de sensibilidade e especificidade. Resultados: Os principais resultados apontam que os valores de massa corporal e estatura autorreferidas tendem a ser bem similares aos aferidos, apesar de algumas exceções. Para os adolescentes, notou-se uma subestimação da estatura, ao passo que, para os idosos, houve superestimação. Com relação à massa corporal, houve consistente subestimação da medida autorreferida entre as mulheres. Entre os homens que praticavam menos de 150 minutos semanais de atividade física no lazer, notou-se superestimação do índice de massa corporal. O processo de calibração das medidas autorreferidas tornou-as mais concordantes com as medidas aferidas, aumentando a sensibilidade na classificação do estado nutricional entre as mulheres e a especificidade entre os homens. Conclusões: As medidas autorreferidas de estatura, massa corporal e índice de massa corporal forneceram medidas válidas e confiáveis, apresentando melhoras substanciais após a calibração.

ABSTRACT: Objective: To evaluate the validity of self-reported body mass and height measurements in adolescents, adults and older adults according to sex, age, leisure-time physical activity level, nutritional status, and cardiometabolic risk factors. Methods: The study included 856 subjects, aged 12 years or older, who participated in the São Paulo Health Survey (ISA-2015) and who had their body mass and height measured and self-reported. Based on the Body Mass Index (BMI), a classification of nutritional status was made according to standardized criteria for each phase of life. The validation of self-reported data was examined by the Intraclass Correlation Coefficient, Bland-Altman and paired T-Test. Linear regression models were used to estimate the calibration coefficients, and sensitivity and specificity tests were performed. Results: Self-reported body mass and height values tend to be very similar to measured values, with a few exceptions. For the adolescents, an underestimation of height was noted, while for the older adults, an overestimation. There was a consistent underestimation of self-reported body mass among women, and an overestimation of BMI among men who practiced less than 150 minutes of physical activity per week during leisure time. The calibration process of self-reported measures made them more consistent with the values measured, increasing the sensitivity in the classification of nutritional status among women and the specificity among men. Conclusions: Self-reported measures of height, body mass and BMI provided valid and reliable measures, presenting a substantial improvement after calibration.

Correlations among vitamin K intake, body fat, lipid profile and glucose homeostasis in adults and the elderly

ABSTRACT Objective Recent research has investigated the possible inverse relationship between vitamin K intake and body fat. In addition, an increasing number of studies are supporting a key role for this vitamin in improving lipid profile and insulin sensitivity and reducing the risk of type 2 diabetes mellitus, but little is known about what mechanisms would be involved. Thus, the objective of this study was to investigate the relationship between vitamin K intake (in the form of phylloquinone - PK), body fat, lipid profile and markers of glucose homeostasis in adults and the elderly. Subjects and methods A cross-sectional study with 298 participants (46% men) in the São Paulo Health Survey 2014-2015. Spearman correlations were performed to evaluate the associations between vitamin K intake and the biochemical and body composition measures. Results Among normal-weight male adults (n = 15), PK intake presented a positive correlation with the quantitative insulin sensitivity check index (QUICKI) (r = 0.525; p = 0.045). Among men with high fat mass index (FMI) (n = 101), PK intake had a negative correlation with homeostasis model assessment estimate for β-cell function (HOMA-β) (r = −0.227; p = 0.022). In women with high FMI (n = 122), PK intake had a negative correlation with HOMA-β (r = −0.199, p = 0.032) and insulin (r = −0.207, p = 0.026). No correlations were found between PK intake and lipid profile. Conclusions Our findings support a potential relationship among PK intake, body fat and markers of glucose homeostasis in adults and the elderly.