Nutrition Metabolism and Cardiovascular Diseases, Mar 1, 2019
Background and aim: Increased ferritin levels have been widely associated with cardiovascular ris... more Background and aim: Increased ferritin levels have been widely associated with cardiovascular risk in adults. Whether ferritin levels and their changes during childhood are related to metabolic syndrome (MetS) at adolescence is unknown. We aimed to evaluate these associations using levels of ferritin at 5, 10 and 16 years and their linear increases and patterns of sustained increased levels across childhood. Methods-There were four samples evaluated according to non-missing values for study variables at each stage (5 years: 562; 10 years: 381; and 16 years: 567 children; non-missing values at any stage: 379). MetS risk was evaluated as a continuous Z score. Patterns of sustained increased ferritin (highest tertile) and slope of the change of ferritin per year across the follow-up were calculated. Results-Ferritin levels in the highest versus lowest tertile at five and 16 years were significantly positively associated with MetS risk Z score at adolescence in boys and these associations were unaffected by adjustment for covariates. Having high, compared to low/moderate ferritin level at 2 or more time periods between 5 and 16 years was related to higher Mets Z-score in boys only[e.g. 5-10 years adjusted-beta (95 %CI):0.26(0.05-0.48),P<0.05]. In girls, ferritin Z score at 10 and 16 years was positively and independently associated with HOMA-IR Z score. In girls, the slope of
Puberal characteristics of school age Chilean girls The characteristics of puberal development we... more Puberal characteristics of school age Chilean girls The characteristics of puberal development were observed in a transversal study of 2328 school age females. This sample was representative of girls from elementary schools of metropolitan Santiago belonging to high, medium and low socioeconomic level (SEL). The age at initiation of puberty ranged from 93 to 183 months for mamary development and for pubic hair from 100 to 1 83 months. A significant chronological difference in the initiation of breast and pubic hair development was found between subjects belonging to medium and low SEL: the mamary development ocurring at an earlier age, compared with high SEE: 123.7 and 122.4 vs 128.6 and 126.8 month of age rcspcctivelly. It is possible that environmental and genetic factors may be involved in this findings.
In Chile, the prevalence of obesity in schoolchildren is 21.3%. The study and individual interven... more In Chile, the prevalence of obesity in schoolchildren is 21.3%. The study and individual intervention of this malnutrition, it is necessary to have not only global indicators of nutritional status, but also indicators that give information on body composition. To compare estimates of body fat isotopic dilution, plethysmography and radiographic absorptiometry 4C model in overweight schoolchildren. We worked with 61 obese (BMI ≥ p 95) of both sexes, between 8 and 13 years, enrolled in a school in a district of the city of Santiago. The multicompartmental body composition determination, considered isotopic dilution, plethysmography and radiographic absorptiometry. Using as a reference standard four compartment model of Fuller. In both sexes, the method showed better agreement with the reference of 4 compartments was isotope dilution (r = 0.98, p < 0.01). In children, the isotopic dilution underestimates body fat in -0.40 kg. By contrast, DEXA and plethysmography overestimate body fa...
OBJECTIVE: To determine patterns of satiety responsiveness and its relationship to eating in the ... more OBJECTIVE: To determine patterns of satiety responsiveness and its relationship to eating in the absence of hunger (EAH), in a cohort of adolescents. We also assessed whether sex, body mass index and duration of breastfeeding, during infancy, predicted satiety responsiveness and eating behavior at 16 years. METHODS: Adolescents (n ¼ 576) from a longitudinal cohort, which began as an iron deficiency anemia preventive trial, participated in an unlimited breakfast after an overnight fast, and reported satiety response on a visual analog scale after the meal, followed by an EAH procedure. Height, weight and body composition were measured before breakfast. Latent profile analysis generated profiles that captured individual differences in satiety responsiveness. Multivariable regressions, adjusted for potential confounders, evaluated the association between: (1) satiety responsiveness and EAH, and (2) breastfeeding in infancy, satiety responsiveness and EAH in adolescence. RESULTS: Participants were on average 16.7-year old, 48% female, 37% overweight/obese and 76% were breastfed as the sole source of milk for o6 months. We found three latent profiles of satiety responsiveness: 1: 'responsive' (49%); 2: 'not responsive' (41%); 3: 'still hungry' (10%). Participants in the 'not responsive' or 'still hungry' profile were more likely to eat during the EAH procedure (odds ratio (OR) ¼ 2.5, 95% confidence interval (CI) ¼ 1.8-3.6). Being breastfed for o6 months was related to higher odds of being in the 'not responsive' or 'still hungry' profile (OR ¼ 1.8, 95% CI ¼ 1.2-2.6) and EAH (OR ¼ 2.2, 95% CI ¼ 1.4-3.3). Satiety responsiveness was not influenced by sex and overweight/obesity. CONCLUSION: After an ad libitum meal, we found varied satiety responses, which related to EAH. Furthermore, shorter breastfeeding duration was associated with poorer satiety response and higher consumption during an EAH procedure. Understanding if breastfeeding influences the development of satiety responsiveness and eating behavior may be important in an era characterized by abundant calorie-dense foods and a plethora of environmental cues promoting consumption.
Family history (FH+) of non transmisible chronic diseases (NTCD) increase MetS risk. In Chile, th... more Family history (FH+) of non transmisible chronic diseases (NTCD) increase MetS risk. In Chile, the MetS affects 27% of overweight children, and fasting hyperglycemia is very low prevalent (4,0%). The objective was to study the prevalence of MetS and the cardiovascular risk factors (CVRF) in overweight children with a family background of NTCD and analyze its association with the number of relatives witth NTCD and with parental history (PH). In 183 overweight children (BMI > or = p85) mean age 11,8 +/- 1,8 (86 males) with a FH+ (parental or grandparental) of NTCD, were assessed the BMI z (CDC / NCHS), waist circumference, blood arterial pressure, fasting Glucose and Insulin (RIA), triglycerides, HDL chol. The MetS and the CVRF were diagnosed using the Cook phenotype and the insulin resistance (IR) through the HOMA-IR. Chi2, ANOVA, t Student and Willcoxon test were performed. The frequency of FH+ of DM2, hypertension and dyslipidemia were 81,4%, 88,0% and 71,6 % respectively. The M...
We examined the association between unhealthy snacking at school and academic outcomes in student... more We examined the association between unhealthy snacking at school and academic outcomes in students from the Santiago Metropolitan Region (Chile). Cross-sectional population-based study. We measured the nutritional quality of snacks at school using an FFQ, and accounting for the amounts of saturated fat, fibre, sugar and salt in the foods, and academic outcomes using national standardized test scores in Language and Mathematics. Multivariate regression analyses modelled the relationship between unhealthy snacking at school (exposure), potential confounders and performance in Mathematics and Language (outcomes). Random sample of 1073 students (13��1 (sd 2��3) years old) attending public, partially subsidized and private schools. Fifty-six per cent of students ate items at snack time that were high in fat, sugar, salt and energy, and thus were considered to have unhealthy snaking. Thirty-six per cent and 8 % were considered to have poor-to-fair and healthy snacking, respectively. Unhealthy snacking significantly lowered the odds of good academic performance in both domains. Students having unhealthy snacks were 56 % less likely to pass in Language (fully adjusted OR=0��44; 95 % CI 0��23, 0��85) and 66 % less likely to pass in Mathematics (fully adjusted OR=0��34; 95 % CI 0��19, 0��64) compared with students having healthy snack items. Schoolchildren eating unhealthy foods at snack time had worse academic performance in Language and Mathematics, as measured by a standardized test. Although association does not imply causation, these findings support the notion that academic and health-related behaviours are linked. More research is needed on the effect of school health programmes on educational outcomes.
The mild chronic inflammatory state associated with obesity may be an important link between adip... more The mild chronic inflammatory state associated with obesity may be an important link between adiposity and insulin resistance (IR). In a sample of 137 overweight and obese Chilean adolescents, we assessed associations between high-sensitivity C-reactive protein (hs-CRP), IR and adiposity; explored sex differences; and evaluated whether hs-CRP mediated the relationship between adiposity and IR. Positive relationships between hs-CRP, IR and 2 measures of adiposity were found. Hs-CRP was associated with waist circumference (WC) in boys and fat mass index (FMI) in girls. Using path analysis, we found that hs-CRP mediated the relationship between adiposity (WC and FMI) and the homeostatic model assessment of insulin resistance (HOMA-IR) (p < 0.05) in both sexes. Our novel finding is that inflammation statistically mediated the well described link between increased adiposity and IR.
Objetives: To evaluate calcium intake and plasma vitamin D levels in ceoliac children. Methods an... more Objetives: To evaluate calcium intake and plasma vitamin D levels in ceoliac children. Methods and Subjets: 25 celiac patients (20 females and 5 males, 5 to 15 years old) with good compliance to gluten free diet for al least the last 2 years. Calcium intake was ...
Background: An a ppropria te mea surement of physica l a ctivity (PA) in children is useful, sinc... more Background: An a ppropria te mea surement of physica l a ctivity (PA) in children is useful, since ina ctivity is a ssocia ted to obesity, ca rdiova scula r a nd meta bolic risk. Aim: To a ssess the relia bility of the INTA questionna ire of PA, to compa re the derived PA score with a ccelerometry a nd to a ssess its a bility to identify excessively ina ctive children. Mater ial and methods: One hundred eighty children a ged 8 to 13 yea rs a nswered a n interviewer-a dministered questionna ire a bout their usua l PA, consisting in 5 items (recumbent, sea ted, wa lking, pla ying outdoor, sports). The a nswers were converted to a PA score with a 0-10 points sca le. Relia bility wa s tested in 87 children by test/retest conducted 3-5 da ys a pa rt. The PA score wa s compa red with 3-da y a ccelerometry in 77 of 93 children (35 obese a nd 42 non obese). Receiver opera ting cha ra cteristic (ROC) curves were used to determine the optima l cutpoint for identify a n excessively sedenta ry child. Results: The test/retest relia bility of the questionna ire wa s 0.69 to 0.93 (Lin coefficient). Accelerometry wa s significa ntly a ssocia ted with PA score (RHO: 0.60, p =0.008), outdoor pla ys (RHO: 0.37, p =0.0009) a nd pra cticing of sports ( RHO: 0.33, p =0.003). Obese children were less a ctive tha n non obese children, a ccording both to PA score a nd to a ccelerometry. The optima l cut-point for cla ssifying a child a s too sedenta ry wa s a score of 5 (sensitivity =0.89). Conclusions: The INTA-test is a va lua ble instrument for mea suring usua l PA in clinica l pra ctice a nd is ea sy to a dminister (Rev Méd Chile 2008; 136: 1155-62). (
Background and aims: Familial, socioeconomic and educational factors are important determinants o... more Background and aims: Familial, socioeconomic and educational factors are important determinants of the prevalence and incidence of obesity in children; low physical activity levels and faulty eating habits in addition to these factors. The aim of this study was to determine in Chilean children, the association between body mass index (BMI), abdominal obesity, physical activity (PAH) and eating (EH) habits with academic achievement of educational institution they attend.
Hypothyroidism induces growth retardation and decreases the circulating concentrations of GH and ... more Hypothyroidism induces growth retardation and decreases the circulating concentrations of GH and IGF-I. To study the effects of thyroid hormone on GHR and IGF-I expression, we measured rat liver and kidney GHR and IGF-I mRNI\ levels by solution hybridization RNase protection assay. Three to six 21 day-old castrated male rats per group were given either pure water or 0.0259 methimazole in their drinking water. and subcutaneous pellet containing either placebo or thyroxine (T4) 2.5 mg. After 13 days. the animals were sacrificed. Serum free T4 and IGF-I levels were determined by RIA. Liver and kidney GHR and IGF-I.WA were measured by solution hybridization using specific antisense riboprobes. Protected bands corresponding to GHR and IGF-I MU4A were quantified using a Phosphorlmager.
High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chi... more High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths Burrows RA, Leiva LB, Weisstaub G, Lera LM, Albala CB, Blanco E, Gahagan S. High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths. Pediatric Diabetes 2011.
Experimental and epidemiological studies suggest that calcium and vitamin D supplements may lower... more Experimental and epidemiological studies suggest that calcium and vitamin D supplements may lower blood pressure. We examined the effect of calcium plus vitamin D supplementation on blood pressure and the incidence of hypertension in postmenopausal women. The Women's Health Initiative Calcium/Vitamin D Trial randomly assigned 36 282 postmenopausal women to receive 1000 mg of elemental calcium plus 400 IU of vitamin D3 daily or placebo in a double-blind fashion. Change in blood pressure and the incidence of hypertension were ascertained. Over a median follow-up time of 7 years, there was no significant difference in the mean change over time in systolic blood pressure (0.22 mm Hg; 95% CI:
To evaluate the agreement between body fat determined by the 4-component (4C) model and anthropom... more To evaluate the agreement between body fat determined by the 4-component (4C) model and anthropometric equations in obese schoolchildren. Methods: The sample included 61 obese children (body mass index Ն p 95) of both sexes, aged 8 to 13 years, from families with a history of chronic non-transmissible disease, recruited from a school in a district of the city of Santiago. The multidimensional determination of body composition (not carried out in a Chilean population) included isotope dilution, air-displacement plethysmography and radiographic absorption. Body fat was calculated using the Fuller 4C model. The results of this model were compared with the anthropometric equations generated by Slaughter, Ellis, Huang, Johnston and Deurenberg. This comparison was performed using Lin's agreement coefficient and the Bland and Altman method. Results: The anthropometric equation that best correlated with the four reference components was Slaughter for males (r = 0.94; p < 0.0001) and Ellis equation (r = 0.96; p < 0.0001) in the females. The Slaughter equation underestimated body fat in males by -0.93 (-6.81 4.96) kg. In females, all of the anthropometric equations underestimated body fat, while Ellis showed the closest difference of 1.12 (-2.92 5.17) kg. Conclusions: The Slaughter equation for obese boys and the Ellis equation in obese girls allowed an adequate estimation of total body fat, applicable to clinical and public health situations.
Nutrition Metabolism and Cardiovascular Diseases, Mar 1, 2019
Background and aim: Increased ferritin levels have been widely associated with cardiovascular ris... more Background and aim: Increased ferritin levels have been widely associated with cardiovascular risk in adults. Whether ferritin levels and their changes during childhood are related to metabolic syndrome (MetS) at adolescence is unknown. We aimed to evaluate these associations using levels of ferritin at 5, 10 and 16 years and their linear increases and patterns of sustained increased levels across childhood. Methods-There were four samples evaluated according to non-missing values for study variables at each stage (5 years: 562; 10 years: 381; and 16 years: 567 children; non-missing values at any stage: 379). MetS risk was evaluated as a continuous Z score. Patterns of sustained increased ferritin (highest tertile) and slope of the change of ferritin per year across the follow-up were calculated. Results-Ferritin levels in the highest versus lowest tertile at five and 16 years were significantly positively associated with MetS risk Z score at adolescence in boys and these associations were unaffected by adjustment for covariates. Having high, compared to low/moderate ferritin level at 2 or more time periods between 5 and 16 years was related to higher Mets Z-score in boys only[e.g. 5-10 years adjusted-beta (95 %CI):0.26(0.05-0.48),P<0.05]. In girls, ferritin Z score at 10 and 16 years was positively and independently associated with HOMA-IR Z score. In girls, the slope of
Puberal characteristics of school age Chilean girls The characteristics of puberal development we... more Puberal characteristics of school age Chilean girls The characteristics of puberal development were observed in a transversal study of 2328 school age females. This sample was representative of girls from elementary schools of metropolitan Santiago belonging to high, medium and low socioeconomic level (SEL). The age at initiation of puberty ranged from 93 to 183 months for mamary development and for pubic hair from 100 to 1 83 months. A significant chronological difference in the initiation of breast and pubic hair development was found between subjects belonging to medium and low SEL: the mamary development ocurring at an earlier age, compared with high SEE: 123.7 and 122.4 vs 128.6 and 126.8 month of age rcspcctivelly. It is possible that environmental and genetic factors may be involved in this findings.
In Chile, the prevalence of obesity in schoolchildren is 21.3%. The study and individual interven... more In Chile, the prevalence of obesity in schoolchildren is 21.3%. The study and individual intervention of this malnutrition, it is necessary to have not only global indicators of nutritional status, but also indicators that give information on body composition. To compare estimates of body fat isotopic dilution, plethysmography and radiographic absorptiometry 4C model in overweight schoolchildren. We worked with 61 obese (BMI ≥ p 95) of both sexes, between 8 and 13 years, enrolled in a school in a district of the city of Santiago. The multicompartmental body composition determination, considered isotopic dilution, plethysmography and radiographic absorptiometry. Using as a reference standard four compartment model of Fuller. In both sexes, the method showed better agreement with the reference of 4 compartments was isotope dilution (r = 0.98, p < 0.01). In children, the isotopic dilution underestimates body fat in -0.40 kg. By contrast, DEXA and plethysmography overestimate body fa...
OBJECTIVE: To determine patterns of satiety responsiveness and its relationship to eating in the ... more OBJECTIVE: To determine patterns of satiety responsiveness and its relationship to eating in the absence of hunger (EAH), in a cohort of adolescents. We also assessed whether sex, body mass index and duration of breastfeeding, during infancy, predicted satiety responsiveness and eating behavior at 16 years. METHODS: Adolescents (n ¼ 576) from a longitudinal cohort, which began as an iron deficiency anemia preventive trial, participated in an unlimited breakfast after an overnight fast, and reported satiety response on a visual analog scale after the meal, followed by an EAH procedure. Height, weight and body composition were measured before breakfast. Latent profile analysis generated profiles that captured individual differences in satiety responsiveness. Multivariable regressions, adjusted for potential confounders, evaluated the association between: (1) satiety responsiveness and EAH, and (2) breastfeeding in infancy, satiety responsiveness and EAH in adolescence. RESULTS: Participants were on average 16.7-year old, 48% female, 37% overweight/obese and 76% were breastfed as the sole source of milk for o6 months. We found three latent profiles of satiety responsiveness: 1: 'responsive' (49%); 2: 'not responsive' (41%); 3: 'still hungry' (10%). Participants in the 'not responsive' or 'still hungry' profile were more likely to eat during the EAH procedure (odds ratio (OR) ¼ 2.5, 95% confidence interval (CI) ¼ 1.8-3.6). Being breastfed for o6 months was related to higher odds of being in the 'not responsive' or 'still hungry' profile (OR ¼ 1.8, 95% CI ¼ 1.2-2.6) and EAH (OR ¼ 2.2, 95% CI ¼ 1.4-3.3). Satiety responsiveness was not influenced by sex and overweight/obesity. CONCLUSION: After an ad libitum meal, we found varied satiety responses, which related to EAH. Furthermore, shorter breastfeeding duration was associated with poorer satiety response and higher consumption during an EAH procedure. Understanding if breastfeeding influences the development of satiety responsiveness and eating behavior may be important in an era characterized by abundant calorie-dense foods and a plethora of environmental cues promoting consumption.
Family history (FH+) of non transmisible chronic diseases (NTCD) increase MetS risk. In Chile, th... more Family history (FH+) of non transmisible chronic diseases (NTCD) increase MetS risk. In Chile, the MetS affects 27% of overweight children, and fasting hyperglycemia is very low prevalent (4,0%). The objective was to study the prevalence of MetS and the cardiovascular risk factors (CVRF) in overweight children with a family background of NTCD and analyze its association with the number of relatives witth NTCD and with parental history (PH). In 183 overweight children (BMI > or = p85) mean age 11,8 +/- 1,8 (86 males) with a FH+ (parental or grandparental) of NTCD, were assessed the BMI z (CDC / NCHS), waist circumference, blood arterial pressure, fasting Glucose and Insulin (RIA), triglycerides, HDL chol. The MetS and the CVRF were diagnosed using the Cook phenotype and the insulin resistance (IR) through the HOMA-IR. Chi2, ANOVA, t Student and Willcoxon test were performed. The frequency of FH+ of DM2, hypertension and dyslipidemia were 81,4%, 88,0% and 71,6 % respectively. The M...
We examined the association between unhealthy snacking at school and academic outcomes in student... more We examined the association between unhealthy snacking at school and academic outcomes in students from the Santiago Metropolitan Region (Chile). Cross-sectional population-based study. We measured the nutritional quality of snacks at school using an FFQ, and accounting for the amounts of saturated fat, fibre, sugar and salt in the foods, and academic outcomes using national standardized test scores in Language and Mathematics. Multivariate regression analyses modelled the relationship between unhealthy snacking at school (exposure), potential confounders and performance in Mathematics and Language (outcomes). Random sample of 1073 students (13��1 (sd 2��3) years old) attending public, partially subsidized and private schools. Fifty-six per cent of students ate items at snack time that were high in fat, sugar, salt and energy, and thus were considered to have unhealthy snaking. Thirty-six per cent and 8 % were considered to have poor-to-fair and healthy snacking, respectively. Unhealthy snacking significantly lowered the odds of good academic performance in both domains. Students having unhealthy snacks were 56 % less likely to pass in Language (fully adjusted OR=0��44; 95 % CI 0��23, 0��85) and 66 % less likely to pass in Mathematics (fully adjusted OR=0��34; 95 % CI 0��19, 0��64) compared with students having healthy snack items. Schoolchildren eating unhealthy foods at snack time had worse academic performance in Language and Mathematics, as measured by a standardized test. Although association does not imply causation, these findings support the notion that academic and health-related behaviours are linked. More research is needed on the effect of school health programmes on educational outcomes.
The mild chronic inflammatory state associated with obesity may be an important link between adip... more The mild chronic inflammatory state associated with obesity may be an important link between adiposity and insulin resistance (IR). In a sample of 137 overweight and obese Chilean adolescents, we assessed associations between high-sensitivity C-reactive protein (hs-CRP), IR and adiposity; explored sex differences; and evaluated whether hs-CRP mediated the relationship between adiposity and IR. Positive relationships between hs-CRP, IR and 2 measures of adiposity were found. Hs-CRP was associated with waist circumference (WC) in boys and fat mass index (FMI) in girls. Using path analysis, we found that hs-CRP mediated the relationship between adiposity (WC and FMI) and the homeostatic model assessment of insulin resistance (HOMA-IR) (p < 0.05) in both sexes. Our novel finding is that inflammation statistically mediated the well described link between increased adiposity and IR.
Objetives: To evaluate calcium intake and plasma vitamin D levels in ceoliac children. Methods an... more Objetives: To evaluate calcium intake and plasma vitamin D levels in ceoliac children. Methods and Subjets: 25 celiac patients (20 females and 5 males, 5 to 15 years old) with good compliance to gluten free diet for al least the last 2 years. Calcium intake was ...
Background: An a ppropria te mea surement of physica l a ctivity (PA) in children is useful, sinc... more Background: An a ppropria te mea surement of physica l a ctivity (PA) in children is useful, since ina ctivity is a ssocia ted to obesity, ca rdiova scula r a nd meta bolic risk. Aim: To a ssess the relia bility of the INTA questionna ire of PA, to compa re the derived PA score with a ccelerometry a nd to a ssess its a bility to identify excessively ina ctive children. Mater ial and methods: One hundred eighty children a ged 8 to 13 yea rs a nswered a n interviewer-a dministered questionna ire a bout their usua l PA, consisting in 5 items (recumbent, sea ted, wa lking, pla ying outdoor, sports). The a nswers were converted to a PA score with a 0-10 points sca le. Relia bility wa s tested in 87 children by test/retest conducted 3-5 da ys a pa rt. The PA score wa s compa red with 3-da y a ccelerometry in 77 of 93 children (35 obese a nd 42 non obese). Receiver opera ting cha ra cteristic (ROC) curves were used to determine the optima l cutpoint for identify a n excessively sedenta ry child. Results: The test/retest relia bility of the questionna ire wa s 0.69 to 0.93 (Lin coefficient). Accelerometry wa s significa ntly a ssocia ted with PA score (RHO: 0.60, p =0.008), outdoor pla ys (RHO: 0.37, p =0.0009) a nd pra cticing of sports ( RHO: 0.33, p =0.003). Obese children were less a ctive tha n non obese children, a ccording both to PA score a nd to a ccelerometry. The optima l cut-point for cla ssifying a child a s too sedenta ry wa s a score of 5 (sensitivity =0.89). Conclusions: The INTA-test is a va lua ble instrument for mea suring usua l PA in clinica l pra ctice a nd is ea sy to a dminister (Rev Méd Chile 2008; 136: 1155-62). (
Background and aims: Familial, socioeconomic and educational factors are important determinants o... more Background and aims: Familial, socioeconomic and educational factors are important determinants of the prevalence and incidence of obesity in children; low physical activity levels and faulty eating habits in addition to these factors. The aim of this study was to determine in Chilean children, the association between body mass index (BMI), abdominal obesity, physical activity (PAH) and eating (EH) habits with academic achievement of educational institution they attend.
Hypothyroidism induces growth retardation and decreases the circulating concentrations of GH and ... more Hypothyroidism induces growth retardation and decreases the circulating concentrations of GH and IGF-I. To study the effects of thyroid hormone on GHR and IGF-I expression, we measured rat liver and kidney GHR and IGF-I mRNI\ levels by solution hybridization RNase protection assay. Three to six 21 day-old castrated male rats per group were given either pure water or 0.0259 methimazole in their drinking water. and subcutaneous pellet containing either placebo or thyroxine (T4) 2.5 mg. After 13 days. the animals were sacrificed. Serum free T4 and IGF-I levels were determined by RIA. Liver and kidney GHR and IGF-I.WA were measured by solution hybridization using specific antisense riboprobes. Protected bands corresponding to GHR and IGF-I MU4A were quantified using a Phosphorlmager.
High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chi... more High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths Burrows RA, Leiva LB, Weisstaub G, Lera LM, Albala CB, Blanco E, Gahagan S. High HOMA-IR, adjusted for puberty, relates to the metabolic syndrome in overweight and obese Chilean youths. Pediatric Diabetes 2011.
Experimental and epidemiological studies suggest that calcium and vitamin D supplements may lower... more Experimental and epidemiological studies suggest that calcium and vitamin D supplements may lower blood pressure. We examined the effect of calcium plus vitamin D supplementation on blood pressure and the incidence of hypertension in postmenopausal women. The Women's Health Initiative Calcium/Vitamin D Trial randomly assigned 36 282 postmenopausal women to receive 1000 mg of elemental calcium plus 400 IU of vitamin D3 daily or placebo in a double-blind fashion. Change in blood pressure and the incidence of hypertension were ascertained. Over a median follow-up time of 7 years, there was no significant difference in the mean change over time in systolic blood pressure (0.22 mm Hg; 95% CI:
To evaluate the agreement between body fat determined by the 4-component (4C) model and anthropom... more To evaluate the agreement between body fat determined by the 4-component (4C) model and anthropometric equations in obese schoolchildren. Methods: The sample included 61 obese children (body mass index Ն p 95) of both sexes, aged 8 to 13 years, from families with a history of chronic non-transmissible disease, recruited from a school in a district of the city of Santiago. The multidimensional determination of body composition (not carried out in a Chilean population) included isotope dilution, air-displacement plethysmography and radiographic absorption. Body fat was calculated using the Fuller 4C model. The results of this model were compared with the anthropometric equations generated by Slaughter, Ellis, Huang, Johnston and Deurenberg. This comparison was performed using Lin's agreement coefficient and the Bland and Altman method. Results: The anthropometric equation that best correlated with the four reference components was Slaughter for males (r = 0.94; p < 0.0001) and Ellis equation (r = 0.96; p < 0.0001) in the females. The Slaughter equation underestimated body fat in males by -0.93 (-6.81 4.96) kg. In females, all of the anthropometric equations underestimated body fat, while Ellis showed the closest difference of 1.12 (-2.92 5.17) kg. Conclusions: The Slaughter equation for obese boys and the Ellis equation in obese girls allowed an adequate estimation of total body fat, applicable to clinical and public health situations.
Uploads
Papers by Raquel Burrows