Biomedical subjects

C Albala

Publications and source records attributed to C Albala.

At least 19 recordsLinked to original sources

PubMed2006

Lack of association between the fatty acid binding protein 2 (FABP2) polymorphism with obesity and insulin resistance in two aboriginal populations from Chile.

The aim of this study was to assess the frequency of fatty acid binding protein 2 (FABP2) Ala54Thr genetic polymorphism and to evaluate its association with obesity and insulin resistance in Chilean aboriginal populations. A sample of 96 urban Aymara and 111 urban Mapuche subjects aged 20-80 years were recruited for this cross-sectional study. Glucose, insulin and lipid profile were measured in fasting plasma samples. Insulin resistance was estimated through the HOMA-IR model. FABP2 Ala54Thr genotypes were determined by PCR followed by RFLP analysis. The allele frequency of Thr54 variant was estimated as 18.2% in Aymara subjects, which is one of the lowest reported to date. The corresponding frequency in Mapuche subjects was 31.9% (p<0.002). Regarding genotype-phenotype associations, no significant differences were found in any of the anthropometric or metabolic variables according to Ala54Thr genotypes. After adjustment by BMI and metabolic variables through a logistic regression analysis, the association of the FABP2 polymorphism with ethnic group persisted (Mapuche group: OR=2.37, 95% CI 1.319-4.277, p=0.004) It is unlikely that Ala54Thr polymorphism of the FABP2 gene plays a relevant role in obesity and insulin resistance in Chilean ethnic groups.

Amino Acid Substitution↗

PubMed2004

Anthropometric measurements in the elderly population of Santiago, Chile.

OBJECTIVE: There are few studies on anthropometry and nutritional status in large and representative samples of elderly populations in Chile and South America. We describe age and sex differences in weight, height, body mass index, knee height, waist circumference, midarm circumference, triceps skinfold thickness, arm muscle area, and calf circumference in Chilean elderly subjects. METHODS: This was a population-based, cross-sectional study. A total of 1220 elderly persons (819 women and 411 men; age range, 60-99 y) were recruited in the city of Santiago (Chile) through a probabilistic sampling procedure carried out from October to December 1999. RESULTS: Men were significantly heavier and taller than women in all age groups, whereas body mass index values were significantly higher in women than in men. All anthropometric variables showed a decrease in average values with aging in men and women. The apparent negative slopes for the decline in average values of body weight with aging was of greater magnitude in women than in men (-0.42 kg/y and -0.54 kg/y in male and female subjects, respectively). However, significant age x sex interaction was detected only for triceps skinfold thickness. In women, quadratic terms for age provided a significantly better fit than did the simple linear model for the association between age and weight, body mass index, waist circumference, triceps skinfold thickness, calf circumference, or midarm circumference. CONCLUSION: These observations indicated that body weight changes associated with aging might be more severe in Chilean women than in men, probably determining a differential pattern of lean and fat mass loss.

Age Distribution↗

PubMed2002

Trends in overweight and obesity prevalence in Chilean children: comparison of three definitions.

OBJECTIVE: To compare trends in prevalence of overweight and obesity among Chilean children using three different criteria. METHODS: Descriptive cross-sectional school-based study to analyse these trends in 6-y-old boys and girls who entered first grade in 1987, 1990, 1993, 1996 and 2000. Gender-specific prevalence of overweight and obesity were determined with three criteria: weight for height (W-H) Z-scores compared to NCHS 1977; present reference used by the Ministry of Health; and body mass index (BMI) compared to the revised US CDC Growth Charts with cut-off values of P85-95 and P-95 and IOTF reference with cut-offs extrapolated from an adult BMI of 25 and 30. RESULTS: The prevalence of overweight determined by W-H (WHO) increased from 15% in 1987 to 20% in 2000 for boys and from 17.2 to 21.8% for girls. With BMI-CDC, the increase was from 13.2 to 19.2% for boys and 12 to 18.5% for girls. With BMI-IOTF, rates were very similar. Prevalence of obesity using W-H (WHO) increased from 6.5% in 1987 to 17% in 2000 for boys and from 7.8 to 18.6% for girls. Using BMI-CDC, the increase was from 5.1 to 14.7% for boys and from 4 to 15.8% for girls; using BMI-IOTF prevalence estimates were much lower. CONCLUSIONS: Obesity prevalence in children has increased over time, and trends are similar independent of criteria. The reference used to define prevalence is important since it provides different estimates. Policy makers should be aware that a spurious drop in prevalence may appear if the IOTF reference is compared to the other criteria.

Body Height↗

PubMed2001

Association between HLA-DQB1 alleles and type 1 diabetes in a case-parents study conducted in Santiago, Chile.

The human leukocyte antigen (HLA) system plays a crucial role in the autoimmune process leading to childhood diabetes. The purpose of this study was to evaluate the association between type 1 diabetes and the polymorphism encoded by the HLA-DQB1 gene by using case-parents trios. The study area was the metropolitan region of Santiago, Chile, and cases were ascertained from March 1997 to August 1998. Genotyping was performed in 94 trios comprising incident cases less than 17 years of age at the time of diagnosis and their parents. The transmission/disequilibrium test was used to detect differential transmission in the HLA-DQB1 locus. The authors found that alleles DQB1(*)0302 and DQB1(*)0201 were strongly associated with the disease. By using 1:3 matched sets of cases-pseudosibs and conditional logistic regression models, allelic relative risks were estimated for DQB1(*)0302 (r = 7.2, 95% confidence interval: 2.8, 18.5) and DQB1(*)0201 (r = 4.7, 95% confidence interval: 1.9, 11.6); DQB1(*)0301 was considered the baseline allele. When case-parents trios were used, alleles DQB1(*)0302 and DQB1(*)0201 were strongly associated with a higher risk of type 1 diabetes in the population of SANTIAGO:

Adolescent↗

PubMed2001

Prevalence of type 2 diabetes and obesity in rural Mapuche population from Chile.

The aim of this study was to estimate the prevalence of Type 2 diabetes, impaired glucose tolerance (IGT), and obesity in the Mapuche natives from rural areas in Chile. This cross-sectional study involved men (n = 95) and women (n = 224) older than 20 y from an aboriginal ethnic group (Mapuches), residing in rural communities from the south of Chile. Prevalence of Type 2 diabetes and IGT was calculated according to the World Health Organization criteria. Data on age, degree of ancestral purity, obesity, and hypertension were also obtained. The prevalence of Type 2 diabetes in rural Mapuche natives was estimated as 3.2% (95% CI: 0.7--9.0) in men and 4.5% (95% CI: 2.2--8.1) in women. The overall prevalence of obesity was 56.1% (95% CI: 50.5--61.6): 40.0% (95% CI: 30.1--40.8) in men and 62.9% (95% CI: 56.3--69.3) in women (P value < 0.001). These data suggest that the prevalence of obesity and Type 2 diabetes has been increasing during recent years in the Mapuche communities. The prevalence estimated in this study is higher than that reported 15 y ago. This suggests an important role of lifestyle changes as a possible explanation for epidemiologic transition.

Adult↗

PubMed2001

Low prevalence of type 2 diabetes despite a high average body mass index in the Aymara natives from Chile.

The aim of this study was to estimate the prevalence of type 2 diabetes mellitus (DM2), impaired glucose tolerance (IGT), and the frequency of dyslipidemia, obesity, and hypertension in the rural Aymara population from Northern Chile. In this cross-sectional study, 196 Aymara adult subjects were characterized with respect to their reported physical activity, fasting plasma glucose levels, insulin concentrations, blood pressures, body mass indexes, and plasma lipid profiles. The participants also underwent a 2-h oral glucose tolerance test. The diagnostic criteria for DM2 and IGT followed those of the World Health Organization. The overall prevalence of DM2 was estimated as 1.5% (95% confidence interval: 0.3--4.5). Overall prevalence of IGT was calculated as 3.6% (1.5--7.3). The occurrence of obesity and dyslipidemia was relatively high in the Aymara population, although the frequency of sedentary habits, and the prevalence of hypertension were low. In conclusion, the prevalence of DM2 in the rural Aymara population living at high altitudes in Northern Chile, was much lower than that of other Amerindian groups that adopted lifestyles from industrialized Western societies. Despite a relatively high prevalence of a body mass index of at least 30 kg/m(2), especially in women (23.5%), high physical activity levels and low plasma-insulin concentrations may have been responsible in part for the low prevalence of DM2 in the Aymara population.

Adult↗

PubMed2001

Obesity trends in Latin America: transiting from under- to overweight.

Latin America is undergoing a rapid demographic and nutritional transition. A recent WHO/PAHO survey on obesity in the region revealed an increasing trend in obesity as countries emerge from poverty, especially in urban areas. In contrast, in middle income countries, obesity tends to decline as income increases; this is especially so in women. Dietary changes and increasing inactivity are considered the crucial contributory factors that explain this rise. The end result is a progressive rise in overweight and obesity, especially in low income groups who improve their income and buy high fat/high carbohydrate energy-dense foods. Intake of these foods increases to the detriment of grains, fruits and vegetables. Most aboriginal populations of the Americas have changed their diet and physical activity patterns to fit an industrialized country model. They now derive most of their diet from Western foods and live sedentary and physically inactive lives. Under these circumstances they develop high rates of obesity, insulin resistance and type 2 diabetes. Supplementary feeding programs are common in the region; the number of beneficiaries significantly exceeds the malnourished. Weight-for-age definition of undernutrition without assessment of length will overestimate the dimension of malnutrition and neglect the identification of stunted overweight children. Providing food to low income stunted populations may be beneficial for some, although it may be detrimental for others, inducing obesity especially in urban areas. Defining the right combination of foods/nutrients, education and lifestyle interventions that are required to optimize nutrition and health is a present imperative.

Adolescent↗

PubMed2001

Nutrition transition in Latin America: the case of Chile.

The nutritional situation of Latin America is changing rapidly from one characterized by underweight and stunting to one where chronic diseases such as cancer, cardiovascular disease, and type 2 diabetes are increasingly prevalent. In Chile, under-nutrition has virtually disappeared, but rising obesity rates and risk factors for chronic diseases indicate the need to modify existing programs and emphasize prevention of diet-related chronic diseases.

Cause of Death↗

PubMed2001

Incidence rate and spatio-temporal clustering of type 1 diabetes in Santiago, Chile, from 1997 to 1998.

OBJECTIVE: To estimate the incidence rate of type 1 diabetes in the urban area of Santiago, Chile, from March 21, 1997 to March 20, 1998, and to assess the spatio-temporal clustering of cases during that period. METHODS: All sixty-one incident cases were located temporally (day of diagnosis) and spatially (place of residence) in the area of study. Knox's method was used to assess spatio-temporal clustering of incident cases. RESULTS: The overall incidence rate of type 1 diabetes was 4.11 cases per 100,000 children aged less than 15 years per year (95% confidence interval: 3.06 - 5.14). The incidence rate seems to have increased since the last estimate of the incidence calculated for the years 1986 - 1992 in the metropolitan region of Santiago. Different combinations of space-time intervals have been evaluated to assess spatio-temporal clustering. The smallest p-value was found for the combination of critical distances of 750 meters and 60 days (uncorrected p-value = 0.048). CONCLUSIONS: Although these are preliminary results regarding space-time clustering in Santiago, exploratory analysis of the data method would suggest a possible aggregation of incident cases in space-time coordinates.

Adolescent↗

PubMed2001

[Auto-antibody profile and breast feeding in type 1 diabetic patients].

BACKGROUND: Islet cell-specific autoantibodies such as islet cell antibody (ICA), antiinsulin (IAA), anti-glutamic acid decarboxylase (GAD) and anti-tyrosine phosphatase (IA2) can be present in patients with type I diabetes. Breast feeding duration and the early exposure to milk substitutes are environmental factors associated to etiology of type 1 diabetes. AIM: To study the frequency of the anti-GAD, anti-IA-2 e ICA antibodies in Chilean type 1 diabetic patients and determine the possible modulator effect of the breast feeding. PATIENTS AND METHODS: One hundred thirty four type 1 diabetic patients, aged one to 15 years old, were studied at the moment of their diagnosis. Patients were classified according to the duration of exclusive breast feeding. IA-2 and GAD were determined by radio immuno assay and ICA by means of indirect immunofluorescence. RESULTS: Subjects with three months or less and those with more than three months of breast feeding were positive for ICA in 78.8 and 90.6% of cases respectively, for GAD in 75 and 54.6% of cases respectively (p = 0.024) and for IA-2 in 73 and 43.8% of cases respectively (p = 0.001). All three antibodies were positive in 53.9 and 21.8% of children with less or more than three months of breast feeding (p = 0.001). CONCLUSION: Both IA-2 and GAD antibodies are less frequently positive in type 1 diabetic patients who have been breast fed for more than three months. These findings suggest a possible attenuating role of exclusive breast feeding on pancreatic aggression events in patients with type 1 diabetes.

Adolescent↗

PubMed2001

Transmission of high-risk HLA-DQB1 alleles in Chilean type 1 diabetic patients and their parents: stratification by the presence of ICA or GAD65 autoantibodies.

AIM: The purpose of this study was to assess whether the transmission of DQB1*0201 and DQB1*0302 alleles from heterozygous parents to Chilean type 1 diabetic patients depends on the presence of antibodies such as glutamic acid decarboxilase (GAD65) or Islet Cell (ICA) autoantibodies in the affected case. MATERIAL AND METHODS: A study of incident type 1 diabetic cases and parents was carried out in Santiago, Chile during 1997-98. The use of the case-parental design eliminates the possibility that case-controls differences are due to selection of controls whose genetic backgrounds differ systematically from those of cases. HLA-DQB1 polymorphisms were determined in cases and parents from n = 83 families using polymerase chain reaction and oligonucleotide dot-blot analysis. Detection of GAD65 antibodies was performed using a simple radio-binding asssay. Conventional ICA were detected by indirect immunofluorescence. RESULTS: Transmission disequilibrium test indicate a strong association between DQB1*0201 and DQB1*0302 and type I diabetes. When comparing the two subsets of families defined by having an affected child tested negative or positive for GAD65 antibodies (39 and 44 case-parent trios respectively) the probability of transmission of DQB1*0201 significantly differed between such strata (p-value=0.025). The pattern of transmission of DQB1*201 allele was also significantly different in the two subsets of families defined by ICA-or ICA+ cases (23 and 60 trios respectively) (p-value = 0.028). No differences were found in the transmission of DQB1*0302 allele in the different strata defined by the autoimmunity status of the proband. CONCLUSION: Our results reveal that DQB1*0201 allele may display distinct associations with type I diabetes depending on the autoimmunity to ICA and GAD65 autoantibodies.

Adolescent↗

PubMed2000

Nutrition policy in the Chilean transition.

OBJECTIVE: This paper examines socioeconomic, demographic, epidemiological and nutrition changes that have occurred in Chile in the last decades using concepts of epidemiological and nutrition transition, and discusses policies related to nutrition. DESIGN AND SETTING: This is a descriptive, population-based study to analyse changes in the Chilean diet and nutrition situation including some of the main demographic, socioeconomic and epidemiological variables. Data came from the FAO, the National Institute of Statistics, the Ministry of Health and national surveys. RESULTS AND POLICY IMPLICATIONS: In Chile, the epidemiological and nutrition situation shifted from a pretransition stage with high rates of undernutrition to a post-transition stage with increasing rates of obesity in all groups aged less than 20 years. However, changes were not accompanied by modifications in nutrition policy, which had been successful in reducing undernutrition. Despite changes in diet to a 'western' diet and in nutritional status of the population from undernutrition to obesity, food and nutrition programmes have been maintained unaltered. Governmental and university organizations were created in 1994 and 1995 to address the current food and nutrition problems. The accomplishments of these institutions have been the elaboration of dietary guidelines, reformulating the food and nutrition programmes and the promulgation of the Food Sanitary Regulations for Chile. CONCLUSIONS: Education for the prevention of nutrition excess problems should be a main food and nutrition policy in developing countries.

Adolescent↗

PubMed2000

Associations between HLA-DQB1 high-risk alleles and type I diabetes do not depend on cytomegalovirus antibody status at onset: a case-parent study conducted in Chile.

The purpose of the present study is to ascertain whether the associations between HLA-DQB1*0201 and DQB1*0302 alleles and childhood diabetes depend on the presence of antibodies to human cytomegalovirus (CMV). A study of incident type I diabetes cases and parents was conducted in Santiago, Chile. HLA-DQB1 polymorphisms were determined in 85 case-parent trios (255 subjects), while the detection of CMV was carried out only in the incident cases. As expected, HLA-DQB1 polymorphisms are strongly associated with type I diabetes, with crude odds ratios of 3.7 (95% confidence interval (CI) 1.8-7.7) for the DQB1*0201 allele and 10.3 (95% CI 5.0-21.4) for the DQB1*0302 allele. In the subset of families with CMV+ cases, the odds ratios were estimated as 3.7 (95% CI 1.6-8.6) for the DQB1*0201 allele and 11.1 (95% CI 4.8-25.8) for the DQB1*0302 allele. In families with patients who tested negative for CMV antibodies, the odds ratios were calculated as 3.5 (95% CI 0.7-16.8) for the DQB1*0201 allele, and 8.0 (95% CI 1.8-34.7) for the DQB1*0302 allele. There was no evidence of statistical interaction between CMV antibodies and the DQB1*0201 allele (P value = 0.9) or the DQB1*0302 allele (P value = 0.7). In conclusion, alleles DQB1*0302 and DQB1*0201 do not display distinct associations with type I diabetes depending on the presence of antibodies for CMV.

Adolescent↗

PubMed2000

Dietary isoflavones affect sex hormone-binding globulin levels in postmenopausal women.

The studies presented in this report were designed to further investigate the causal association between phytoestrogen action and increase in sex hormone-binding globulin (SHBG) levels. Phytoestrogens include isoflavones that bind to estrogen receptors and therefore exert estrogenic action. This study included 20 postmenopausal women that ingested 30 g soy milk daily for 10 weeks. Plasma concentrations of isoflavones and SHBG were measured. Total isoflavones significantly increased from 0.014 +/- 0.01 micromol/L (baseline) to 0.53 +/- 0.19 ,micromol/L, and paired responses showed that some subjects clearly increased their SHBG levels. The percent change in SHBG showed a positive correlation with phytoestrogen concentration; all women who had circulating phytoestrogen levels above 0.6 micromol/L increased by at least 30% their SHBG values. Results suggest that phytoestrogens may significantly increase SHBG in subjects whose SHBG concentrations are in the low end of the concentration range.

Aged↗

PubMed2000

[Obesity and leptin association in three Chilean aboriginal populations].

BACKGROUND: Although there is a clear relationship between body mass index and leptin levels, few authors have addressed the possible influence of ethnic factors on these levels. AIM: To measure serum leptin in three different Chilean aboriginal populations. SUBJECTS AND METHODS: Fasting serum leptin and insulin levels were measured by radioimmunoassay in 345 rural mapuche individuals, 247 rural aymara subjects and 162 urban mapuche subjects. A body mass index of 27.5 kg/m2 was used as cutoff point to classify study subjects. RESULTS: Among the three ethnic groups, women had serum leptin levels three times higher than men. In all three ethnic groups, there was a significant association between leptin levels, body mass index and gender (r2 = 0.32 and 0.5 p < 0.001, in rural mapuche, r2 = 0.32 and 0.5 p < 0.001, in aymara and r2 = 0.24 and 0.49, p < 0.001 in urban mapuche populations). No differences in leptin levels were observed for the interaction between age and insulin. The increments per quartile in leptin levels were lower among mapuche than aymara individuals. CONCLUSIONS: Rural mapuche individuals have a high frequency of obesity. However their leptin levels are lower than those of aymara or urban mapuche populations. The higher leptin levels observed in urban mapuche subjects could be due to environmental influences.

Adult↗

PubMed2000

[Relationship between leptin and insulin blood levels in obese and lean Chilean women].

BACKGROUND: Leptin, a product of ob gene and insulin blood levels, are proportional to the amount of adipose tissue. Insulin could have an independent regulatory effect on leptin secretion. AIM: To assess the relationship between serum leptin and plasma insulin levels in obese and lean Chilean women. MATERIAL AND METHODS: One hundred forty five women, aged 20 to 60 years old, were studied. Weight, height, waist and hip circumference, fasting blood glucose, insulin and leptin levels were measured. Insulin resistance was assessed using the homeostasis model assessment. The relationship between different variables was determined using multiple linear regression, variance analysis and non parametric correlation. RESULTS: Leptin serum concentrations were positively correlated with body mass index, insulin plasma levels and degree of insulin resistance. The association of leptin with insulin was independent of body mass index and persisted after adjustments by body fat distribution and age. CONCLUSIONS: Insulin and insulin resistance are associated to high blood leptin levels and this association is independent of the degree of adiposity and body fat distribution.

Adult↗

PubMed1999

Applicability of the case-parent design in the etiological research of Type 1 diabetes in Chile and other genetically mixed populations.

In case-control studies, spurious associations between Human Leukocyte Antigen (HLA) alleles and Type 1 diabetes could arise as a result of population stratification, if there are ethnic differences between cases and non-related controls. The Chilean population has several unique features which make it ideal for the study of the effect of stratification by ethnicity on genetic epidemiological research. The incidence rates of Type 1 diabetes in Chilean Aboriginal populations are very low compared to Caucasian populations, while the frequency of the alleles in HLA loci also vary across ethnic groups. In order to avoid the confounding effect of ethnicity, one possible remedy would be the use of cases and their parents in place of non-related controls. The case-parent design offers an adequate framework for the study of the association between HLA polymorphisms and Type 1 diabetes in the Chilean population and can also be applicable to other genetically mixed populations especially in the Americas.

Adolescent↗

PubMed1999

Apolipoprotein E polymorphism in elderly Chilean people with Alzheimer's disease.

As a part of the WHO Age-Associated Dementia Project, Chile has been participating in a cross-national survey on dementia frequency and determinants since 1989. In the present study, apolipoprotein E (ApoE) polymorphism genotypes have been compared in 95 patients with Alzheimer's disease (AD) (mean age 80.7; 95% CI 79.2-82.2, range 66-97) and 187 healthy people (mean age 78.2; 95% CI 77.2-79.2, range 65-93). Isoelectric focusing and immunoblotting with anti-human ApoE polyclonal antibody were used to determine the distribution of ApoE genotypes. Dementia was diagnosed according to DSM-III-R and ICD-10 clinical criteria. The diagnosis of probable or possible AD was made according to the NINCDS-ADRDA criteria. The ApoE allele frequencies in healthy people were calculated to be epsilon2 = 0.07, epsilon3 = 0.74 and epsilon4 = 0.19. In the probable AD disease group, the frequencies were epsilon2 = 0.08, epsilon3 = 0.52 and epsilon4 = 0.40. The odds ratio (OR) for epsilon4 carriers compared with non-epsilon4 carriers was estimated to be 2.9 (95% CI 1.7-5.1). Taking the genotype epsilon3/epsilon3 as the reference group, the OR for the epsilon4/epsilon4 genotype was estimated to be 12.8 (95% CI 3.9-47.6) and for epsilon3/epsilon4 subjects it was 2.4 (1.3-4.5). These results support the association between ApoE epsilon4 allele with late-onset AD in a Chilean population.

Aged↗