Luiz Antonio dos Anjos

Biological and socio-cultural determinants of physical activity in adolescents

A atividade fisica e um comportamento importante na promocao de saude e na prevencao de doencas. Para que se desenvolvam programas eficazes no incentivo a pratica de atividade fisica em adolescentes, torna-se necessario que se identifiquem os fatores que a determinam. Este estudo pretende rever alguns dos aspectos do estado atual do conhecimento acerca da influencia de determinantes demografico-biologicos (idade, sexo, estatuto socio-economico) e socio-culturais (familia, pares e professor de educacao fisica) na atividade fisica de adolescentes. Nesta revisao apenas foram incluidos estudos efetuados com amostras superiores a 100 adolescentes com idades entre os 10 e os 18 anos, que tenham adotado delineamentos de pesquisa transversal e que tenham utilizado questionarios. Os principais resultados e conclusoes foram que: a idade parece estar negativamente associada a atividade fisica; o sexo masculino tende a estar mais envolvido nessas atividades; o estatuto socio-economico elevado parece ser um fator protetor do risco de inatividade fisica; a participacao da familia e dos pares em atividades fisicas parece estar positivamente associada as atividades por parte dos adolescentes; o professor de educacao fisica parece nao representar um fator propiciador da atividade fisica.

Reference values of handgrip dynamometry of healthy adults: a population-based study.

BACKGROUND & AIMS Although maximal voluntary handgrip strength (HGS) is considered a reliable tool in nutritional assessment there are few reference data available. This paper presents reference values for handgrip strength of healthy adults (age > or = 20 years) from a household survey. METHODS Data were obtained from a representative sample of adults (1122 males and 1928 females) living in Niterói, Rio de Janeiro, Brazil. HGS was measured three times with a Jamar mechanical dynamometer in both hands and the highest value used in the analysis. The percentile distribution of HGS was calculated according to sex and age categories. RESULTS Mean values of right and left HGS were 42.8 and 40.9 kg for males, and 25.3 and 24.0 kg for females, respectively. HGS increased with age and significantly decreased after 40 and 50 year-olds for women and men, respectively. Body mass index (BMI) was associated with HGS in both sexes but only underweight male subjects had significantly lower HGS values. CONCLUSIONS The highest HGS values are observed at the 4th decade of life with significant declines thereafter. HGS is significantly associated with BMI. The reference values of HGS may be useful in assessing the nutritional status of similar adult urban population.

Índice de massa corporal (massa corporal.estatura-2) como indicador do estado nutricional de adultos: revisão da literatura

The limitations and possible uses of the body mass index (BMI) or Quételet index, calculated as the ratio of body mass (kg), and squared stature (m), as an indicator of the nutritional status of adults, are reviewed. The cut-off values for overweight (BMI > or = 25) and chronic energy deficiency (BMI < 18.5) are discussed in the light of the available international literature. Even though BMI does not assess the body composition (BC) of individuals, the case with which it is measured is a strong argument for the use of BMI in epidemiological studies associated otherwise with other anthropometric measurement until such a time as simpler field methods of the assessment of BC are developed.Sao discutidas as virtudes, limitacoes e possiveis aplicacoes do indice de massa corporal (IMC), tambem chamado de indice de Quetelet, que e calculado pela divisao da massa corporal em quilogramas pelo quadrado da estatura em metros, como indicador do estado nutricional de adultos. Baseado numa revisao ampla da literatura, os limites de corte para a definicao de sobrepeso (IMC ³ 25) e desnutricao energetica cronica (IMC < 18,5) sao apresentados e discutidos. Conclui-se que apesar de nao representar a composicao corporal de individuos, a facilidade de sua mensuracao e a grande disponibilidade de dados de massa corporal e estatura parecem ser motivos suficientes para a utilizacao do IMC em estudos epidemiologicos, em associacao (ou nao) a outras medidas antropometricas, ate que metodologias de campo que expressem a composicao corporal sejam desenvolvidas para tais estudos.The limitations and possible uses of the body mass index (BMI) or Quetelet index, calculated as the ratio of body mass (kg), and squared stature (m), as an indicator of the nutritional status of adults, are reviewed. The cut-off values for overweight (BMI ³ 25) and chronic energy deficiency (BMI < 18.5) are discussed in the light of the available international literature. Even though BMI does not assess the body composition (BC) of individuals, the case with which it is measured is a strong argument for the use of BMI in epidemiological studies associated otherwise with other anthropometric measurement until such a time as simpler field methods of the assessment of BC are developed.

Perfil antropométrico da população idosa brasileira. Resultados da Pesquisa Nacional sobre Saúde e Nutrição

This paper presents the nutritional status of the elderly Brazilian population (60 years and older) based on a probabilistic sample survey in 1989. Nutritional assessment used the BMI (kg/m2), with cut-off points recommended by the WHO (1995). Socio-demographic variables included age, gender, region and place of residence in the country (urban/rural area), income, education, and housing conditions. Prevalence rates for thinness (BMI < 18.5) and overweight (BMI ( 25) were 7.8% and 30.4% in men and 8.4% and 50.2% in women, higher than in the young adult population. Thinness was more frequent in older women, in rural areas from the Midwest/Northeast regions (women) and Southeast/Midwest (men), in groups with lower income, less schooling, and worse housing conditions. Overweight was more frequent in women from urban areas in the South and Southeast and groups with higher income, more schooling, and better housing conditions. The results indicate problematic nutritional status in the Brazilian elderly, particularly women.

Crescimento e estado nutricional em amostra probabilística de escolares no Município do Rio de Janeiro, 1999

Growth and nutritional status were assessed in a probabilistic sample of public schoolchildren (1,705 girls and 1,682 boys) in the city of Rio de Janeiro in 1999. Nutritional status of the under-10-year group was assessed by z < -2 (undernutrition) for body mass for height and height for age and by z > +2 for body mass for height (overweight). For children over 10, the 5th and 85th percentiles of body mass index for age were used to assess underweight and overweight, respectively. Prevalence rates of overweight and obesity according to the International Obesity Task Force criteria were also calculated. Prevalence rates for undernutrition were below expected for the reference population. Prevalence of overweight was approximately 18% and 14% for girls and boys, respectively, and obesity was 5% for both sexes. The results of the present study are similar to findings from population-based surveys in Brazil: low prevalence of undernutrition and high prevalence of overnutrition.

Déficit estatural nas crianças brasileiras: relação com condições sócio-ambientais e estado nutricional materno

The relationship between stunting in Brazilian children with their mothers nutritional status and their social-environmental situation was assessed in a probabilistic sample of the Brazilian population in 1989. Data from 12644 mother-son pairs were analyzed. Maternal nutritional status was classified based on the body mass index and stunting was identified in children with stature or length for age Z < or = -2 of the American growth reference curve (NCHS). Stunting was observed in 14.4% of the children (15.9% of boys and 12.9% of girls) There was an inverse relationship between the level of stunting and maternal education, income and house living conditions. Children of illiterate mothers showed more stunting (OR = 17.2) than children whose mothers had had at least 9 years of formal education. Stunting was more frequently observed in children whose mothers were underweight (OR = 2.5), and who were from the first quartile of family income in comparison to the fourth quartile (OR = 11.0) and lived in the poorest living conditions (OR = 7.6). These results suggest a positive association between stunted children and underweight mothers.

Use of handgrip strength in the assessment of the muscle function of chronic kidney disease patients on dialysis: a systematic review

BACKGROUND Even though handgrip strength (HGS) is considered a simple and reliable method to evaluate muscle function and, indirectly, the nutritional status in clinical settings, there is still no consensus concerning its use in patients with chronic kidney disease (CKD) undergoing dialysis. This study presents a systematic review of the literature on the use of HGS as a parameter for nutritional assessment and a prognostic marker in patients on dialysis. METHODS The MEDLINE database (1966 to October 2009) was consulted for this systematic review by using the search terms hand strength or muscle strength dynamometer and dialysis. Eighteen articles were identified and included in the analysis. RESULTS Similar to the general population, HGS values were associated with age and gender. The analysed studies showed correlation between muscle function estimated by HGS and variables used in the assessment of muscle mass and nutritional status, as well as the prediction of clinical complications. CONCLUSIONS The analysis indicates that HGS is a useful tool for continuous and systematic assessment of muscle mass related to nutritional status in patients on dialysis. However, it is still necessary to standardize the techniques used for HGS, especially with respect to the position of measurement, the evaluation period, the choice of arm side and the diagnostic criterion.

Distribuição dos valores do índice de massa corporal da população brasileira até 25 anos

This paper presents the percentage distribution of the body mass index of the Brazilian population from birth to age 25, based on a national survey conducted in 1989. Survey data show that body mass index decreases from birth until around 6 years of age, reaching a plateau at 8 years and progressively increasing until the age of 19 or 20 years for females and 20 or 21 for males. The survey also revealed that after the age of 12 females present a greater body mass index than males, as well as a larger range of percentile values (from 3 to 97). A comparison with data from other countries showed that the body mass index profile in Brazil is similar to that observed in France, Great Britain, and the United States. Before the age of 6, Brazilian youngsters have a mean body mass index that resembles that of North American children, and a lower one thereafter. A comparison between the median body mass index of Brazilian and British youngsters revealed consistently lower values among Brazilian females. When compared to that of France, Brazils male population has a systematically lower body mass index after the age of 8. It is suggested that the data presented in our study be used only for comparing groups of individuals and studies, and not for screening or clinical monitoring, due to the great variability in growth patterns during adolescence.

Aspectos históricos e metodológicos da medição e estimativa da taxa metabólica basal: uma revisão da literatura

This paper reviews the most relevant aspects of measuring basal metabolic rate (BMR). The authors discuss individual and lifestyle factors (age, anthropometry, smoking, physical activity, diet, menses, and ethnicity) as well as possible environmental factors at time of measurement which may alter BMR values. Various available predictive equations, especially those recommended by the World Health Organization in 1985, and subsequent validation studies, particularly in populations living in the tropics, are presented. The review indicates the need for more information on BMR from populations living in different parts of the world so that better estimates can be provided for clinicians and epidemiologists.

A comparison of distribution curves of body mass index from Brazil and the United States for assessing overweight and obesity in Brazilian adolescents

OBJECTIVE To assess the validity of recommendations for use of the 85th and 95th percentiles of body mass index (BMI) of the population in the United States of America as a screening tool to assess overweight/obesity in adolescents. METHODS We investigated the relation between BMI and percent body fat in 1,540 adolescents (717 males and 823 females) aged 10 to 17.9 years old from a private high school in Niterói, a city in the state of Rio de Janeiro, Brazil. We used bioelectric impedance, with the appropriate equations for adolescents, to estimate percent body fat, which served as the gold standard (30% for girls and 25% for boys) to calculate the sensitivity and specificity of the 85th and 95th percentiles of the United States and Brazilian distribution curves of BMI. RESULTS Sensitivity and specificity were high (above 80%) for the Niterói boys, except for the 85th percentile of the Brazilian curve (specificity = 61.8%) and for the 95th percentile of the United States curve (sensitivity = 55.4%). For the Niterói girls, the 85th- and 95th-percentile BMI cutoff points, from both the United States and Brazilian curves, showed low sensitivity, and that sensitivity decreased with age. Specificity was high for the girls, and much higher than it was for the boys. CONCLUSIONS These data suggest that using BMI to screen for overweight/obesity in adolescents can generate a high percentage of false-positives for Niterói boys and an even higher percentage of false-negatives for Niterói girls. A more universal approach to using anthropometric measures to screen for overweight/obesity should be developed, preferably linked to stages of maturation.