Association between soft drinks intake and low glomerular filtration rate in Mexican adults: Results from RenMex

BACKGROUND & AIMS

To evaluate the association between soft drinks (SDs) consumption and estimated glomerular filtration rate (eGFR) in a Mexican adult population.

METHODS

We used data from the RenMex consortium (n = 2095) that included the Mexican Teachers Cohort Study (34-65 years), the Health Workers Cohort Study (18-90 years), and the Comitán Study (19-91 years). In this cross-sectional study, we assessed SDs consumption (cola and flavored soda) using a food frequency questionnaire (FFQ) and estimated eGFR using the CKD Epidemiology Collaboration equation. Quantile regression was used to assess the association between SDs consumption and eGFR with eGFR as a continuous variable. Multinomial logistic regression models were used for eGFR categories derived from quantile regression (mildly decreased eGFR, ≥72.9-87.9 mL/min/1.73 m2 and moderately decreased eGFR, <72.9 mL/min/1.73 m2).

RESULTS

Mean age of study participants was 47.2 years, 67.5% were women, and 12.2% had diabetes. eGFR was <60 mL/min/1.73 m2 in 3.7% of study participants. Mildly decreased eGFR was present in 14.8%, and moderately decreased eGFR was present in 10.1% of study participants. Quantile regression results showed that SDs consumption was associated with lower eGFR at the 10th, 25th, 50th and 75th percentile. Based on the final adjusted multinomial model, ≥7 servings/week was positively associated with moderately decreased eGFR relative to <1 serving/week (Relative Risk Ratio = 1.95; 95% CI: 1.07-3.57).

CONCLUSION

Our results suggest that higher SDs consumption is associated with lower eGFR. Encouraging healthy dietary choices should be part of the management and prevention of CKD.

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

BACKGROUND

Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories.

METHODS

We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5-19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median).

FINDINGS

From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness.

INTERPRETATION

The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity.

FUNDING

UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

Genetic drivers of heterogeneity in type 2 diabetes pathophysiology

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance.

The power of TOPMed imputation for the discovery of Latino-enriched rare variants associated with type 2 diabetes

AIMS/HYPOTHESIS

The Latino population has been systematically underrepresented in large-scale genetic analyses, and previous studies have relied on the imputation of ungenotyped variants based on the 1000 Genomes (1000G) imputation panel, which results in suboptimal capture of low-frequency or Latino-enriched variants. The National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) released the largest multi-ancestry genotype reference panel representing a unique opportunity to analyse rare genetic variations in the Latino population. We hypothesise that a more comprehensive analysis of low/rare variation using the TOPMed panel would improve our knowledge of the genetics of type 2 diabetes in the Latino population.

METHODS

We evaluated the TOPMed imputation performance using genotyping array and whole-exome sequence data in six Latino cohorts. To evaluate the ability of TOPMed imputation to increase the number of identified loci, we performed a Latino type 2 diabetes genome-wide association study (GWAS) meta-analysis in 8150 individuals with type 2 diabetes and 10,735 control individuals and replicated the results in six additional cohorts including whole-genome sequence data from the All of Us cohort.

RESULTS

Compared with imputation with 1000G, the TOPMed panel improved the identification of rare and low-frequency variants. We identified 26 genome-wide significant signals including a novel variant (minor allele frequency 1.7%; OR 1.37, p=3.4 × 10-9). A Latino-tailored polygenic score constructed from our data and GWAS data from East Asian and European populations improved the prediction accuracy in a Latino target dataset, explaining up to 7.6% of the type 2 diabetes risk variance.

CONCLUSIONS/INTERPRETATION

Our results demonstrate the utility of TOPMed imputation for identifying low-frequency variants in understudied populations, leading to the discovery of novel disease associations and the improvement of polygenic scores.

DATA AVAILABILITY

Full summary statistics are available through the Common Metabolic Diseases Knowledge Portal ( https://t2d.hugeamp.org/downloads.html ) and through the GWAS catalog ( https://www.ebi.ac.uk/gwas/ , accession ID: GCST90255648). Polygenic score (PS) weights for each ancestry are available via the PGS catalog ( https://www.pgscatalog.org , publication ID: PGP000445, scores IDs: PGS003443, PGS003444 and PGS003445).

Multi-ancestry genome-wide study in >2.5 million individuals reveals heterogeneity in mechanistic pathways of type 2 diabetes and complications

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes. To characterise the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study (GWAS) data from 2,535,601 individuals (39.7% non-European ancestry), including 428,452 T2D cases. We identify 1,289 independent association signals at genome-wide significance (P<5×10-8) that map to 611 loci, of which 145 loci are previously unreported. We define eight non-overlapping clusters of T2D signals characterised by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial, and enteroendocrine cells. We build cluster-specific partitioned genetic risk scores (GRS) in an additional 137,559 individuals of diverse ancestry, including 10,159 T2D cases, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned GRS are more strongly associated with coronary artery disease and end-stage diabetic nephropathy than an overall T2D GRS across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings demonstrate the value of integrating multi-ancestry GWAS with single-cell epigenomics to disentangle the aetiological heterogeneity driving the development and progression of T2D, which may offer a route to optimise global access to genetically-informed diabetes care.

Diminishing benefits of urban living for children and adolescents' growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1-6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5-19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m-2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.

Erratum: Ancestral diversity improves discovery and fine-mapping of genetic loci for anthropometric traits-The Hispanic/Latino Anthropometry Consortium

[This corrects the article DOI: 10.1016/j.xhgg.2022.100099.].

The Mexican Consortium of Epidemiological Studies for the Prevention, Diagnosis, and Treatment of Chronic Kidney Disease: a review of collaborating studies

Objective. To harmonize participants’ information from five epidemiological studies. Materials and methods. The Mexican Consortium of Epidemiological Studies for the Prevention, Diagnosis, and Treatment of Chronic Kidney Disease (RenMex, by its Spanish acronym) was established in 2018. RenMex is a consortium of five studies: The Mexican Teachers Cohort Study; the Mexico City Diabetes Study; the Health Workers Cohort Study; the Comitán Study; and the Salt Consumption in Mexico Study, which assessed baseline serum creatinine, albumin, and C-reactive protein, all performed with standardized techniques. Results. RenMex includes 3 133 participants, with a mean age of 44.8 years, 68.8% women, 10.8% with a previous medical diagnosis of type 2 diabetes, and 24.1% living with obesity. Conclusions. In the future, RenMex will work on more detailed analyses with each cohort allowed to opt in or out for each topic according to their individual data.

Exome Sequencing Data Analysis and a Case-Control Study in Mexican Population Reveals Lipid Trait Associations of New and Known Genetic Variants in Dyslipidemia-Associated Loci

Background: Plasma lipid levels are a major risk factor for cardiovascular diseases. Although international efforts have identified a group of loci associated with the risk of dyslipidemia, Latin American populations have been underrepresented in these studies.

Objective: To know the genetic variation occurring in lipid-related loci in the Mexican population and its association with dyslipidemia.

Methods: We searched for single-nucleotide variants in 177 lipid candidate genes using previously published exome sequencing data from 2838 Mexican individuals belonging to three different cohorts. With the extracted variants, we performed a case-control study. Logistic regression and quantitative trait analyses were implemented in PLINK software. We used an LD pruning using a 50-kb sliding window size, a 5-kb window step size and a r2 threshold of 0.1.

Results: Among the 34251 biallelic variants identified in our sample population, 33% showed low frequency. For case-control study, we selected 2521 variants based on a minor allele frequency ≥1% in all datasets. We found 19 variants in 9 genes significantly associated with at least one lipid trait, with the most significant associations found in the APOA1/C3/A4/A5-ZPR1-BUD13 gene cluster on chromosome 11. Notably, all 11 variants associated with hypertriglyceridemia were within this cluster; whereas variants associated with hypercholesterolemia were located at chromosome 2 and 19, and for low high density lipoprotein cholesterol were in chromosomes 9, 11, and 19. No significant associated variants were found for low density lipoprotein. We found several novel variants associated with different lipemic traits: rs3825041 in BUD13 with hypertriglyceridemia, rs7252453 in CILP2 with decreased risk to hypercholesterolemia and rs11076176 in CETP with increased risk to low high density lipoprotein cholesterol.

Conclusions: We identified novel variants in lipid-regulation candidate genes in the Mexican population, an underrepresented population in genomic studies, demonstrating the necessity of more genomic studies on multi-ethnic populations to gain a deeper understanding of the genetic structure of the lipemic traits.

Multi-ancestry genetic study of type 2 diabetes highlights the power of diverse populations for discovery and translation

We assembled an ancestrally diverse collection of genome-wide association studies (GWAS) of type 2 diabetes (T2D) in 180,834 affected individuals and 1,159,055 controls (48.9% non-European descent) through the Diabetes Meta-Analysis of Trans-Ethnic association studies (DIAMANTE) Consortium. Multi-ancestry GWAS meta-analysis identified 237 loci attaining stringent genome-wide significance (P < 5 × 10-9), which were delineated to 338 distinct association signals. Fine-mapping of these signals was enhanced by the increased sample size and expanded population diversity of the multi-ancestry meta-analysis, which localized 54.4% of T2D associations to a single variant with >50% posterior probability. This improved fine-mapping enabled systematic assessment of candidate causal genes and molecular mechanisms through which T2D associations are mediated, laying the foundations for functional investigations. Multi-ancestry genetic risk scores enhanced transferability of T2D prediction across diverse populations. Our study provides a step toward more effective clinical translation of T2D GWAS to improve global health for all, irrespective of genetic background.

Ancestral diversity improves discovery and fine-mapping of genetic loci for anthropometric traits-The Hispanic/Latino Anthropometry Consortium

Hispanic/Latinos have been underrepresented in genome-wide association studies (GWAS) for anthropometric traits despite their notable anthropometric variability, ancestry proportions, and high burden of growth stunting and overweight/obesity. To address this knowledge gap, we analyzed densely imputed genetic data in a sample of Hispanic/Latino adults to identify and fine-map genetic variants associated with body mass index (BMI), height, and BMI-adjusted waist-to-hip ratio (WHRadjBMI). We conducted a GWAS of 18 studies/consortia as part of the Hispanic/Latino Anthropometry (HISLA) Consortium (stage 1, n = 59,771) and generalized our findings in 9 additional studies (stage 2, n = 10,538). We conducted a trans-ancestral GWAS with summary statistics from HISLA stage 1 and existing consortia of European and African ancestries. In our HISLA stage 1 + 2 analyses, we discovered one BMI locus, as well as two BMI signals and another height signal each within established anthropometric loci. In our trans-ancestral meta-analysis, we discovered three BMI loci, one height locus, and one WHRadjBMI locus. We also identified 3 secondary signals for BMI, 28 for height, and 2 for WHRadjBMI in established loci. We show that 336 known BMI, 1,177 known height, and 143 known WHRadjBMI (combined) SNPs demonstrated suggestive transferability (nominal significance and effect estimate directional consistency) in Hispanic/Latino adults. Of these, 36 BMI, 124 height, and 11 WHRadjBMI SNPs were significant after trait-specific Bonferroni correction. Trans-ancestral meta-analysis of the three ancestries showed a small-to-moderate impact of uncorrected population stratification on the resulting effect size estimates. Our findings demonstrate that future studies may also benefit from leveraging diverse ancestries and differences in linkage disequilibrium patterns to discover novel loci and additional signals with less residual population stratification.

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

BACKGROUND

Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories.

METHODS

We used data from 1990 to 2019 on people aged 30-79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age.

FINDINGS

The number of people aged 30-79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306-359) million women and 317 (292-344) million men in 1990 to 626 (584-668) million women and 652 (604-698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55-62) of women and 49% (46-52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43-51) of women and 38% (35-41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20-27) for women and 18% (16-21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran.

INTERPRETATION

Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings.

FUNDING

WHO.

Determinants of penetrance and variable expressivity in monogenic metabolic conditions across 77,184 exomes

Hundreds of thousands of genetic variants have been reported to cause severe monogenic diseases, but the probability that a variant carrier develops the disease (termed penetrance) is unknown for virtually all of them. Additionally, the clinical utility of common polygenetic variation remains uncertain. Using exome sequencing from 77,184 adult individuals (38,618 multi-ancestral individuals from a type 2 diabetes case-control study and 38,566 participants from the UK Biobank, for whom genotype array data were also available), we apply clinical standard-of-care gene variant curation for eight monogenic metabolic conditions. Rare variants causing monogenic diabetes and dyslipidemias display effect sizes significantly larger than the top 1% of the corresponding polygenic scores. Nevertheless, penetrance estimates for monogenic variant carriers average 60% or lower for most conditions. We assess epidemiologic and genetic factors contributing to risk prediction in monogenic variant carriers, demonstrating that inclusion of polygenic variation significantly improves biomarker estimation for two monogenic dyslipidemias.

Genetic discovery and risk characterization in type 2 diabetes across diverse populations

Genomic discovery and characterization of risk loci for type 2 diabetes (T2D) have been conducted primarily in individuals of European ancestry. We conducted a multiethnic genome-wide association study of T2D among 53,102 cases and 193,679 control subjects from African, Hispanic, Asian, Native Hawaiian, and European population groups in the Population Architecture Genomics and Epidemiology (PAGE) and Diabetes Genetics Replication and Meta-analysis (DIAGRAM) Consortia. In individuals of African ancestry, we discovered a risk variant in the TGFB1 gene (rs11466334, risk allele frequency (RAF) = 6.8%, odds ratio [OR] = 1.27, p = 2.06 × 10⁻⁸), which replicated in independent studies of African ancestry (p = 6.26 × 10⁻²³). We identified a multiethnic risk variant in the BACE2 gene (rs13052926, RAF = 14.1%, OR = 1.08, p = 5.75 × 10⁻⁹), which also replicated in independent studies (p = 3.45 × 10⁻⁴). We also observed a significant difference in the performance of a multiethnic genetic risk score (GRS) across population groups (p_{heterogeneity} = 3.85 × 10⁻²⁰). Comparing individuals in the top GRS risk category (40%–60%), the OR was highest in Asians (OR = 3.08) and European (OR = 2.94) ancestry populations, followed by Hispanic (OR = 2.39), Native Hawaiian (OR = 2.02), and African ancestry (OR = 1.57) populations. These findings underscore the importance of genetic discovery and risk characterization in diverse populations and the urgent need to further increase representation of non-European ancestry individuals in genetics research to improve genetic-based risk prediction across populations.

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

BACKGROUND

Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents.

METHODS

For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5-19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence.

FINDINGS

We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9-10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes-gaining too little height, too much weight for their height compared with children in other countries, or both-occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls.

INTERPRETATION

The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks.

FUNDING

Wellcome Trust, AstraZeneca Young Health Programme, EU.

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries1,2. However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world3 and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health4,5. However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular risk-changed from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.

Diabetes is associated with a higher risk of mortality among women in a middle-income country: Results form the Mexican Teacher's cohort study

AIMS

In Mexico City, the mortality rate among patients with diabetes appears to be four times that of people without diabetes. Our study aimed to refine analyses of the impact of diabetes on mortality in a large cohort of women from different areas in Mexico with healthcare insurance.

METHODS

Our study followed 111,299 women with comprehensive healthcare coverage from the Mexican Teachers' Cohort. After a median follow-up of 7.8years, 5514 (5%) prevalent self-reported diabetes cases and 4023 incident cases were identified, while deaths were identified through employers' databases and next-of-kin reports, with dates and causes of death for 1121 women obtained from mortality databases. Hazard ratios (HRs) for total and cause-specific mortality were estimated by Cox regression models, using follow-up time as the time scale and allowing for time-variable diabetes status after adjusting for age, socioeconomic status, use of health services, and anthropometric and lifestyle variables.

RESULTS

In multivariable-adjusted models, the HR for all-cause mortality was 3.28 (95% CI: 2.86-3.75) in women with vs. without diabetes. The impact of diabetes on mortality was higher in rural vs. urban areas (HR: 4.72 vs. 2.98, respectively). HRs were 1.57 and 23.44 for cancer and renal disease mortality, respectively.

CONCLUSION

In women with healthcare coverage in Mexico, the magnitude of the association between diabetes and all-cause mortality was higher than that observed in high-income countries, but less than what has previously been reported for Mexico. Such elevated mortality suggests a lack of adequate access to quality diabetes care in the population despite comprehensive healthcare coverage.

Mexican Carriers of the HNF1A p.E508K Variant Do Not Experience an Enhanced Response to Sulfonylureas

OBJECTIVE

To assess whether an ethnic-specific variant (p.E508K) in the maturity-onset diabetes of the young (MODY) gene hepatocyte nuclear factor-1α (HNF1A) found in Mexicans is associated with higher sensitivity to sulfonylureas, as documented in patients with MODY3.

RESEARCH DESIGN AND METHODS

We recruited 96 participants (46 variant carriers and 50 age- and sex-matched noncarriers). Response to glipizide (one 2.5-5.0-mg dose), metformin (four 500-mg doses), and an oral glucose challenge was evaluated using a previously validated protocol. Glucose and insulin levels and their areas under the curve (AUCs) were compared between groups.

RESULTS

Carriers of the p.E508K variant had a lower maximum insulin peak during the glipizide challenge as compared with noncarriers with diabetes (P < 0.05). Also, carriers had a lower insulin response after the oral glucose challenge. Following an oral glucose tolerance test in the presence of metformin, carriers of the p.E508K variant with diabetes had a lower maximum insulin peak and total and incremental insulin AUC value as compared with noncarriers with diabetes (P < 0.05). A similar but nonsignificant trend was seen in participants without type 2 diabetes.

CONCLUSIONS

Carriers of variant p.E508K in HNF1A have a reduced insulin response rather than the increased sensitivity to sulfonylureas seen in patients with MODY3.

A Loss-of-Function Splice Acceptor Variant in IGF2 Is Protective for Type 2 Diabetes

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage-dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction.

Diabetic by HbA1c, Normal by OGTT: A Frequent Finding in the Mexico City Diabetes Study

Context:

The agreement between glucose-based and hemoglobin A1c (HbA1c)–based American Diabetes Association criteria in the diagnosis of normal glucose tolerance, prediabetes, or diabetes is under scrutiny. A need to explore the issue among different populations exists.

Objective:

Examine the results obtained with both methods in the diagnosis of the glycemic status.

Design:

The Mexico City Diabetes Study is a population-based, prospective investigation.

Setting:

Low-income elder urban community.

Participants:

All 854 participants without known diabetes had both oral glucose tolerance test (OGTT) and HbA1c measurements on the same day of the 2008 phase.

Interventions:

Standardized protocol: questionnaires, anthropometry, and biomarkers.

Main Outcome:

Diagnostic classification of American Diabetes Association criteria.

Results:

We found by OGTT normal glucose tolerance (NGT) in 512 (59.9%) participants, prediabetes [impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT)] in 261 (30.5%), and diabetes in 81 (9.4%). In total, 232 in the NGT group (45.3%) and 158 in the prediabetes group (60.5%) had HbA1c ≥6.5%. Body mass index, waist circumference, and blood pressure were significantly different among OGTT-defined diabetic status groups but not in the HbA1c-diagnosed group. We identified 404 participants in the NGT group with confirmed NGT throughout all phases of the Mexico City Diabetes Study. Of these, 184 (45.5%) had HbA1c ≥6.5%. In a vital/diabetes status follow-up performed subsequently, we found that, of these, 133 remained nondiabetic, 3 had prediabetes, 7 had diabetes, and 13 had died without diabetes; we were unable to ascertain the glycemic status in 5 and vital status in 23.

Conclusions:

Normal OGTT coexisting with elevated HbA1c is a common finding in this cohort. It is possible that this finding is not mediated by hyperglycemia. This might occur in similar populations.

Genome-wide association study of colorectal cancer in Hispanics

This manuscript describes the first large-scale genome-wide association study of colorectal cancer in Hispanics and Latinos. Our results demonstrate the broad replication of known susceptibility regions and the importance of fine-mapping in ethnic minority populations.

Genome-wide association studies (GWAS) have identified 58 susceptibility alleles across 37 regions associated with the risk of colorectal cancer (CRC) with P < 5×10⁻⁸. Most studies have been conducted in non-Hispanic whites and East Asians; however, the generalizability of these findings and the potential for ethnic-specific risk variation in Hispanic and Latino (HL) individuals have been largely understudied. We describe the first GWAS of common genetic variation contributing to CRC risk in HL (1611 CRC cases and 4330 controls). We also examine known susceptibility alleles and implement imputation-based fine-mapping to identify potential ethnicity-specific association signals in known risk regions. We discovered 17 variants across 4 independent regions that merit further investigation due to suggestive CRC associations (P < 1×10⁻⁶) at 1p34.3 (rs7528276; Odds Ratio (OR) = 1.86 [95% confidence interval (CI): 1.47–2.36); P = 2.5×10⁻⁷], 2q23.3 (rs1367374; OR = 1.37 (95% CI: 1.21–1.55); P = 4.0×10⁻⁷), 14q24.2 (rs143046984; OR = 1.65 (95% CI: 1.36–2.01); P = 4.1×10⁻⁷) and 16q12.2 [rs142319636; OR = 1.69 (95% CI: 1.37–2.08); P=7.8×10⁻⁷]. Among the 57 previously published CRC susceptibility alleles with minor allele frequency ≥1%, 76.5% of SNPs had a consistent direction of effect and 19 (33.3%) were nominally statistically significant (P < 0.05). Further, rs185423955 and rs60892987 were identified as novel secondary susceptibility variants at 3q26.2 (P = 5.3×10^–5) and 11q12.2 (P = 6.8×10⁻⁵), respectively. Our findings demonstrate the importance of fine mapping in HL. These results are informative for variant prioritization in functional studies and future risk prediction modeling in minority populations.

Incidence of type 2 diabetes in Mexico: results of the Mexico City Diabetes Study after 18 years of follow-up

OBJECTIVE

To estimate the incidence of type 2 diabetes (T2D) in Mexican population.

MATERIALS AND METHODS

Population based prospective study. At baseline (1990), the population at risk (1939 non-diabetic adults 35-64 years) was evaluated with oral glucose tolerance test. Subsequent similar evaluations were done (1994, 1998, 2008). American Diabetes Association diagnostic criteria were applied.

RESULTS

The period of observation was 27842 person-years, the cumulative incidence of T2D was 14.4 and 13.7 per 1000 person-years for men and women, respectively. Incidence was 15.8, 15.7 and 12.7 per 1 000 person-years for the second (1994), third (1998) and fourth (2008) follow-up phases, respectively. The mean age at diagnosis was 44 years for prevalent cases and 56 years for incident cases.

CONCLUSIONS

This is the first estimate of long-term incidence of T2D in Mexican population. The incidence is among the highest reported worldwide. It remained with few changes throughout the study period.

Sweetened beverages intake, hyperuricemia and metabolic syndrome: the Mexico City Diabetes Study

OBJECTIVE. To determine prevalence of hyperuricemia and its relation with intake of sweetened beverages (SB) and metabolic syndrome (MS) in low income urban Mexican population. MATERIALS AND METHODS. A cross-sectional analysis of The Mexico City Diabetes Study, a prospective population-based investigation (1 173 participants) was performed. We used logistic regression, adjusted by pertinent variables. We determined prevalence of hyperuricemia and explored associations of uric acid levels with MS and intake of SB. RESULTS. Prevalence of hyperuricemia was 26.5 and 19.8% in males and females respectively. In an adjusted multivariate model, body mass index, waist circumference, and triglyceride were higher as uric acid quartiles increased (p<0.005-0.001). The odds ratio for MS was 1.48 for 3rd uric acid quartile and 2.03 for 4th quartile. Higher consumption of SB was associated with higher uric acid levels (p<0.001). CONCLUSION. Prevalence of hyperuricemia is high. Potential association with intake of SB, resulting in metabolic alterations should be considered.

Risk factors associated to diabetes in Mexican population and phenotype of the individuals who will convert to diabetes

 Objective. To describe risk factors associated to the inci­dence of type 2 diabetes (T2D) in Mexican population and to define phenotypic (clinical, anthropometric, metabolic) characteristics present in the individual who will convert to diabetes, regardless of time of onset. Materials and meth­ods. The Mexico City Diabetes Study began in 1990, with 2 282 participants, and had three subsequent phases: 1994, 1998, and 2008. A systematic evaluation with an oral glucose tolerance test was performed in each phase. For diagnosis of T2D, American Diabetes Association criteria were used. Results. The population at risk was 1939 individuals. Sub­jects who were in the converter stage (initially non diabetic that eventually converted to T2D) had, at baseline, higher BMI (30 vs 27), systolic blood pressure (119 vs 116 mmHg), fasting glucose (90 vs 82mg/dl), triglycerides (239 vs 196mg/dl), and cholesterol (192 vs 190mg/dl), compared with sub­jects who remained non converters (p<0.05). Conclusion. The phenotype described represents a potentially identifiable phase and a target for preventive intervention.

Association of a low-frequency variant in HNF1A with type 2 diabetes in a Latino population

IMPORTANCE

Latino populations have one of the highest prevalences of type 2 diabetes worldwide.

OBJECTIVES

To investigate the association between rare protein-coding genetic variants and prevalence of type 2 diabetes in a large Latino population and to explore potential molecular and physiological mechanisms for the observed relationships.

DESIGN, SETTING, AND PARTICIPANTS

Whole-exome sequencing was performed on DNA samples from 3756 Mexican and US Latino individuals (1794 with type 2 diabetes and 1962 without diabetes) recruited from 1993 to 2013. One variant was further tested for allele frequency and association with type 2 diabetes in large multiethnic data sets of 14,276 participants and characterized in experimental assays.

MAIN OUTCOME AND MEASURES

Prevalence of type 2 diabetes. Secondary outcomes included age of onset, body mass index, and effect on protein function.

RESULTS

A single rare missense variant (c.1522G>A [p.E508K]) was associated with type 2 diabetes prevalence (odds ratio [OR], 5.48; 95% CI, 2.83-10.61; P = 4.4 × 10(-7)) in hepatocyte nuclear factor 1-α (HNF1A), the gene responsible for maturity onset diabetes of the young type 3 (MODY3). This variant was observed in 0.36% of participants without type 2 diabetes and 2.1% of participants with it. In multiethnic replication data sets, the p.E508K variant was seen only in Latino patients (n = 1443 with type 2 diabetes and 1673 without it) and was associated with type 2 diabetes (OR, 4.16; 95% CI, 1.75-9.92; P = .0013). In experimental assays, HNF-1A protein encoding the p.E508K mutant demonstrated reduced transactivation activity of its target promoter compared with a wild-type protein. In our data, carriers and noncarriers of the p.E508K mutation with type 2 diabetes had no significant differences in compared clinical characteristics, including age at onset. The mean (SD) age for carriers was 45.3 years (11.2) vs 47.5 years (11.5) for noncarriers (P = .49) and the mean (SD) BMI for carriers was 28.2 (5.5) vs 29.3 (5.3) for noncarriers (P = .19).

CONCLUSIONS AND RELEVANCE

Using whole-exome sequencing, we identified a single low-frequency variant in the MODY3-causing gene HNF1A that is associated with type 2 diabetes in Latino populations and may affect protein function. This finding may have implications for screening and therapeutic modification in this population, but additional studies are required.

Hyperinsulinemia is Associated with Increased Soluble Insulin Receptors Release from Hepatocytes

It has been generally assumed that insulin circulates freely in blood. However it can also interact with plasma proteins. Insulin receptors are located in the membrane of target cells and consist of an alpha and beta subunits with a tyrosine kinase cytoplasmic domain. The ectodomain, called soluble insulin receptor (SIR) has been found elevated in patients with diabetes mellitus. We explored if insulin binds to SIRs in circulation under physiological conditions and hypothesize that this SIR may be released by hepatocytes in response to high insulin concentrations. The presence of SIR in rat and human plasmas and the culture medium of hepatocytes was explored using Western blot analysis. A purification protocol was performed to isolated SIR using affinity, gel filtration, and ion exchange chromatographies. A modified reverse hemolytic plaque assay was used to measure SIR release from cultured hepatocytes. Incubation with 1 nmol l(-1) insulin induces the release of the insulin receptor ectodomains from normal rat hepatocytes. This effect can be partially prevented by blocking protease activity. Furthermore, plasma levels of SIR were higher in a model of metabolic syndrome, where rats are hyperinsulinemic. We also found increased SIR levels in hyperinsulinemic humans. SIR may be an important regulator of the amount of free insulin in circulation. In hyperinsulinemia, the amount of this soluble receptor increases and this could lead to higher amounts of insulin bound to this receptor, rather than free insulin, which is the biologically active form of the hormone. This observation could enlighten the mechanisms of insulin resistance.

Associations between surrogate measures of insulin resistance and waist circumference, cardiovascular risk and the metabolic syndrome across Hispanic and non-Hispanic white populations

AIMS

We evaluated the relations between surrogate indices of insulin resistance and waist circumference, metabolic syndrome and coronary heart disease risk across Hispanic and non-Hispanic white populations.

METHODS

The study was a cross-sectional analysis of participants without diabetes in the San Antonio Heart Study, Mexico City Diabetes Study and Spanish Insulin Resistance Study. We evaluated commonly used indices of insulin resistance, including homeostasis model assessment, McAuley's index, Gutt's insulin sensitivity index, Avignon's insulin sensitivity index and the Stumvoll index with and without demographics, the modified Matsuda index and the product of the triglycerides and glucose index. The metabolic syndrome was defined by American Heart Association/National Heart, Lung, and Blood Institute criteria and coronary heart disease risk by Framingham risk scores.

RESULTS

The Stumvoll index with demographics and the Avignon's insulin sensitivity index had the strongest correlations with waist circumference across populations. The triglycerides and glucose and McAuley's indices had the most robust correlations with Framingham risk score. The triglycerides and glucose index had the greatest ability to detect individuals with the metabolic syndrome and ≥ 10% coronary heart disease risk. Some indices display significant variability in the strength of the relationship with adiposity and coronary heart disease risk across populations.

CONCLUSIONS

There are significant differences between insulin resistance indices regarding the ability to detect the metabolic syndrome and coronary heart disease risk across populations. Studies may need to consider the index of insulin resistance that best suits the objectives.

The status of diabetes care in Mexican population: are we making a difference? Results of the National Health and Nutrition Survey 2006

OBJECTIVE

Examine clinical indicators to evaluate diabetes care in Mexico.

MATERIAL AND METHODS

Diabetics (self reported, with therapy) were examined with standardized questionnaires, anthropometry, glucose, lipids and glycohemoglobin. Data were analyzed statistically.

RESULTS

There were 2 644 patients, 677 cases without access to medical care (73% women), most lived in rural communities and spoke aboriginal dialect. Prevalence of obesity for private access group was 21.2%, for other or non access group was between 31 and 65%. The group without or basic education was most common, 76% of the cases had HDL <40 mg/dl and 36% had hypertriglyceridemia. Only 6.6% of patients had HbA1c <7%. There was no significant difference between HbA1c values observed in the group with or without access. Most patients were treated with oral agents. A significant group was without therapy. Assessments for complications was infrequent.

CONCLUSIONS

Current model for diabetes care in Mexico is inefficacious and a paradigm change is necessary.

Triglycerides and high-density lipoprotein cholesterol are associated with insulinemia in adolescents

OBJECTIVE

The aim of this study was to evaluate the association between lipids and insulin concentration in adolescents.

MATERIAL AND METHODS

A cross-sectional study of 350 adolescents aged 14-19 years old from a public high school in Guadalajara, in the state of Jalisco, Mexico, was conducted. Fasting insulin concentration was determined using microparticle enzyme immunoassay; total cholesterol and triglycerides were detected by standard enzymatic procedures;and low- and high-density lipoproteins were found using standard precipitation methods. Statistical analysis included linear multivariate regression.

RESULTS

Serum triglycerides were associated positively with insulin fasting (beta = 0.003, p = 0.0001) and high-density lipoprotein cholesterol was negatively associated with insulin fasting in male adolescents 18-19 years old (beta = -0.03, p = 0.012).

CONCLUSIONS

The relationships between triglycerides and insulin and between high-density lipoprotein cholesterol and insulin are already present in adolescence.

Does the metabolic syndrome improve identification of individuals at risk of type 2 diabetes and/or cardiovascular disease?

OBJECTIVE

The metabolic syndrome has been promoted as a method for identifying high-risk individuals for type 2 diabetes and cardiovascular disease (CVD). We therefore sought to compare this syndrome, as defined by the National Cholesterol Education Program, to the Diabetes Predicting Model and the Framingham Risk Score as predictors of type 2 diabetes and CVD, respectively.

RESEARCH DESIGN AND METHODS

A population-based sample of 1,709 initially nondiabetic San Antonio Heart Study (SAHS) participants were followed for 7.5 years, 195 of whom developed type 2 diabetes. Over the same time interval, 156 of 2,570 SAHS participants experienced a cardiovascular event. A population-based sample of 1,353 initially nondiabetic Mexico City Diabetes Study (MCDS) participants were followed for 6.5 years, 125 of whom developed type 2 diabetes. Baseline measurements included medical history, age, sex, ethnicity, smoking status, BMI, blood pressure, fasting and 2-h plasma glucose levels, and fasting serum total and HDL cholesterol and triglycerides.

RESULTS

The sensitivities for predicting diabetes with the metabolic syndrome were 66.2 and 62.4% in the SAHS and the MCDS, respectively, and the false-positive rates were 27.8 and 38.7%, respectively. The sensitivity and false-positive rates for predicting CVD with the metabolic syndrome in the SAHS were 67.3 and 34.2%, respectively. At corresponding false-positive rates, the two predicting models had significantly higher sensitivities and, at corresponding sensitivities, significantly lower false-positive rates than the metabolic syndrome for both end points. Combining the metabolic syndrome with either predicting model did not improve the prediction of either end point.

CONCLUSIONS

The metabolic syndrome is inferior to established predicting models for either type 2 diabetes or CVD.

Geography of diabetes mellitus mortality in Mexico: an epidemiologic transition analysis

BACKGROUND

The worldwide prevalence of diabetes mellitus (DM) will increase from 135 to 300 million cases by the year 2025. In Mexico, DM is the third cause of general mortality and the primary cause of mortality in the 55- to 64-year-old age group. The purpose of this study was to analyze the characteristics of DM mortality trends in Mexico from 1980 to 2000 in the context of this epidemiologic transition.

METHODS

Age-adjusted mortality rates were estimated for DM as underlying cause of death using World Health Organization (WHO) reference population. To evaluate magnitude of risks, standardized mortality ratio (SMR) was calculated; prematurity of mortality was evaluated by means of potential lost life years index (PLLYI). Diabetes mortality trends in the U.S. were calculated with information from the Centers for Disease Control (CDC) public registry and were age-adjusted for comparison.

RESULTS

Total number of deaths due to DM during the period was 582,826. Standardized mortality ratio by state showed higher mortality in the northern Mexican states; PLLYI was higher in the northern states. Mortality trends in Mexico showed a rapid increase during the 1980s followed by a less acute increment in the 1990s. Age-adjusted mortality rate trends in the U.S. were lower than those in Mexico.

CONCLUSIONS

This study shows an increase in DM age-adjusted mortality trends during the years 1980-2000 in Mexico. The observed pattern of mortality varies widely throughout the country, probably due to differences in socioeconomic conditions and in access to healthcare.

Seven-year incidence and progression of obesity. Characterization of body fat pattern evolution in low-income Mexico City urban population

BACKGROUND

There are no prospective data regarding the natural history of obesity in Mexico. The objective of this research was to investigate the incidence and progression of obesity in a low-income sector of Mexico City and to characterize evolution of body fat pattern distribution.

METHODS

We carried out a population-based, prospective survey. Total on-site population was 15,532 persons; we determined as eligible all 35 to 64-year-old men and nonpregnant women for a total of 3,505. We interviewed at baseline 3,319 (94.7%) individuals and examined 2,282 (65.1%). At follow-up approximately 7 years later, we interviewed 1,764 (77.3%) subjects and examined 1,594 (69.9%). Measurements for all participants included height, weight, body mass index (BMI), waist-hip circumference, and subscapular and triceps skinfold thickness. Overweight was defined as BMI > or = 25 and < or = 29.9 kg/m2, while grade 1 obesity was BMI >or = 30 and < or = 34.9 kg/m2, grade 2 was > or = 35 and < or = 39.9, and grade 3, > or = 40 kg/m2.

RESULTS

At baseline, prevalence of overweight was 48.6%, and grade 1 obesity, 22.7%, grade 2, 5.1%, and grade 3 obesity was 1.4%; at follow-up, these were 45.2, 25.8, 6.6, and 2.3%, respectively. At baseline, mean BMI in women was 29.1 +/- 0.16 kg/m2 and in men, 27.3 +/- 0.15 kg/m2; at follow-up, it reached 29.4 +/- 0.17 kg/m2 in women and 27.4 +/- 0.16 kg/m2 in men. Waist circumference increased from mean of 99.7 +/- 0.44 cm in women to 101.2 +/- 0.42 cm; in men, mean waist circumference rose from 95.2 +/- 0.38 to 96.7 +/- 0.39 cm.

CONCLUSIONS

The obesity epidemic in this population possesses serious proportions that increase risk for severe metabolic consequences. There is a need for intervention.

Weight, physical activity, and smoking as determinants of insulinemia in adolescents

BACKGROUND

It is known that insulinemia is the result of the interaction among several factors, such as weight, body fat pattern distribution, and physical activity as well as ethnicity. There is little information regarding this question among Mexican adolescents. The association among fasting insulin levels, weight, fat distribution, physical activity, and cigarette smoking was studied in Mexican adolescents.

METHODS

Cross-sectional data were collected from 352 Mexican adolescents aged 14-19 years (response rate 41.5%). Fasting insulin levels were measured by microparticle enzyme immunoassay; body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference (WC) were determined using standardized techniques, while physical activity was determined by 7-day Stanford physical activity inventory. Cigarette smoking was defined as number of cigarettes/year.

RESULTS

Increased BMI and waist circumference, low physical activity, younger age, and non-smoking were associated with high insulin levels. Non-smokers had higher fasting insulin levels compared to smokers (57.8 pmol +/- 1.84 vs. 49.7 pmol/L +/- 2.8; p = 0.034). However, adjusted odds ratio (OR) between insulin and smoking status was not significant. Multivariate analysis showed the following: insulin increased 1.06 pmol/L for each unit of change in BMI; increased 1.02 pmol/L for each unit of change in waist circumference; increased 1.16 pmol/L for non-smoking, and decreased 1.07 pmol/L for each 250 kcal/day of energy expenditure.

CONCLUSIONS

Our results support the concept that Mexican adolescents who are overweight have abdominal fat distribution and physical inactivity, and significant hyperinsulinemia. The relationship between smoking and lower insulinemia found in this research warrants further study.

Prevalence of hypertension in a Mexican population according to the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure

BACKGROUND

Hypertension in Mexico represents a challenging public health problem. The National Survey on Chronic Diseases published in 1993 reported that hypertension affects more than 10 million Mexicans. No information has been published regarding the prevalence of hypertension in Mexico using the new diagnostic criteria established by the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC VI).

METHODS

The Mexico City Diabetes Study is a prospective study designed to estimate the prevalence and incidence of cardiovascular risk factors in a low-income area. The survey included 941 men and 1341 non-pregnant women aged 35-64 years. Blood pressure measurements were performed using a random zero sphygmomanometer. The diagnostic criteria for hypertension were those recommended by the JNC VI.

RESULTS

The crude prevalence of hypertension was 17.2% and 18.1% in men and women, respectively. We found significant associations between hypertension and obesity, body fat distribution, very-low-density lipoprotein cholesterol, fasting and 2-h post-glucose in both sexes, and between hypertension and total cholesterol, low-density lipoprotein cholesterol and triglycerides levels in women. In 40% of hypertensive men and 23% of women, hypertension was undiagnosed and untreated. Of the previously diagnosed hypertensive individuals, 38% of men and 30% of women reported not taking antihypertensive medicine. The prevalence++ of associated risk factors in this population is 12.3% for tobacco consumption, 22.4% for diabetes, 49.8% for hypertriglyceridemia and 40.9% for hypercholesterolemia.

CONCLUSIONS

Hypertension occurs in 18% of this population. There is a high prevalence of undiagnosed and untreated cases. Associated cardiovascular risk factors are highly prevalent.

[Incidence and progression of diabetic retinopathy in low income population of Mexico City]

Diabetic retinopathy is one of the leading causes of preventable blindness in working age population. Diabetes mellitus and this microvascular complication affects frequently Mexican population and presents itself in severe clinical forms. There are no incidence studies of diabetic retinopathy in Mexico. The four year incidence and progression of diabetic retinopathy were investigated in low income diabetic patients of Mexico City. In the follow up phase we studied 164 patients, 76.6% of the patients studied at baseline, 63 were men and 101 women. All participants had a complete ophthalmological exam and seven field stereo photographs. All photographs were graded using internationally accepted criteria in the reading center of our institution. The four year incidence of any level of retinopathy was 22.5%. Worsening of retinopathy occurred in 20.6% and the proliferative diabetic retinopathy stage was reached in 4.5%. Incidence of diabetic retinopathy was associated to age at diagnosis of diabetes mellitus of less than 45 years and progression was associated to duration of disease of more than ten years. The four year incidence of macular edema was 8.8%. These data are important to plan strategies for prevention of blindness and the implementation of optimal care of diabetic patients in our country.

Differential impact of obesity in related populations

To search for genetic and environmental determinants of obesity, we compared the prevalences and the impact of obesity in three populations from two cities: Mexican Americans (n = 820) and non-Hispanic whites (n = 1112) from San Antonio, Texas, and Mexicans from Mexico City (n = 1878). In the age range examined, 35-64 years, only Mexican men and women showed a significant increase in the prevalence of obesity with age. On the other hand, genetic ancestry, especially in women, made significant differences in the rates of obesity. Mexican Americans showed relatively high, and non-Hispanic whites low, rates of obesity. To discriminate between genetic and environmental influences mediating the impact of obesity on a set of hemodynamic and metabolic variables, we compared this impact between Mexican Americans and both non-Hispanic whites (same macro-environment, different gene pools), and Mexicans (same gene pool, different environments). We found that obesity always worsens the hemodynamic and metabolic profiles of individuals, but the magnitude of the effects may be variable. We showed that the levels of insulin concentrations for a given level of obesity were similar in Mexicans and Mexican Americans, suggesting that genetic influences predominate in determining insulin levels; the levels of triglycerides and HDL for a given level of obesity were similar in Mexican Americans and non-Hispanic whites, suggesting predominant environmental influences on lipid levels. On the other hand, the levels of glucose and systolic blood pressure for a given level of obesity were usually different between Mexican Americans and either of the other two populations, suggesting that these levels may result from genotype-by-environment interactions.

Racial admixture in a Mestizo population from Mexico City

Seven genetic systems were used to investigate the racial composition of a sample from a low-income Mexico City Mestizo group, finding estimates of 0.590, 0.348, and 0.062 of Indian, White, and Black ancestry, respectively. The results are similar to another Mexico City group studied previously and to several Mestizo populations from different parts of the country. The one thing in common in all these groups is low socioeconomic status. There is only one report suggesting that Mexico City Mestizos have around 70% White ancestry, and there is reason to believe the sample was taken from a high socioeconomic group. It is suggested that low socioeconomic Mexican Mestizo groups are characterized by a high Indian ancestry, above 50%. © 1995 Wiley-Liss, Inc.

[The use of hospital services by diabetic patients: study in an open population]

The results of a population based survey, carried on in a low income area of Mexico City, with a total population of 15,532 inhabitants, are presented. From these, 3,505 individuals were considered eligible (35-64 years of age and non pregnant women). A home interview was performed in 2,810 households (80.17%). Physical exam with oral glucose tolerance test was performed in 2,282 (65.10%) participants. A total of 340 patients were identified as type II diabetics (WHO criteria); 140 of them were males and 200 females. Impaired glucose tolerance (IG) was diagnosed in 376 subjects, 120 (12.78%) of whom were males and 256 (19.06%) females. Approximately three years after the first exam, an attempt was made to recontact all the participants. A home or telephone interview was obtained in 2,139 subjects; they were asked if they had been hospitalized in the past three years, their length of stay and the cause. Due to incomplete data 194 subjects were excluded from the analyses presented in this report. A total of 101 participants that had normal glucose tolerance were hospitalized (6.4%). Of the ones diagnosed as IG, 15 (5.45%) were hospitalized. Of the patients diagnosed as diabetics 31 (12.5%) were hospitalized. At least 30 per cent of this excess demand is potentially preventable, since it is related directly to decompensation of DM control. We identified the need to implement a mechanism for guaranteeing entrance of all patients diagnosed with IG to health facilities.(ABSTRACT TRUNCATED AT 250 WORDS)

[Tobacco use in Mexico City]

The results of a population based study carried out in a low income area of Mexico City are presented in this paper. The study was designed to investigate tobacco consumption as a cardiovascular risk factor in the population ages range of 35-64 years. A home interview was accomplished for 2,155 individuals. Monthly family income, employment status, years of schooling and tobacco consumption were investigated. The majority of the participants reported a monthly family income of 500 to one hundred new pesos and the average of school years was 5.8 +/- 3.2 years. In most cases (93.8%), participants reported to have a paid job and only 2.09 per cent were unemployed. A total of 74.2 of men and 24.5 per cent of women reported that they had smoked at least 50 cigarettes in their lifespan and 52.5 per cent of men and 17.9 of women were current smokers. Most smokers (62.9% men, 74.5% women) consume 10 or less cigarettes per day, but 33.2 per cent of men and 24.2 of women were heavy smokers, that is 10-29 cigarettes per day. Only eleven men and seven women smoked cigars or pipe. This results show a high rate of tobacco consumption in this population, therefore it is imperative to strengthen education programs aimed at promoting healthier habits and to stop tobacco consumption.

[Prevalence of diabetes and glucose intolerance in a urban population at a low economic level]

In this report we present the results of an epidemiologic survey performed in a low income urban neighborhood. The study was designed to investigate the prevalence of type II diabetes mellitus (DM) and impaired glucose tolerance (IGT) in this socioeconomic stratum. The study was done using the standard procedure for the oral glucose tolerance test (OGT) and the recommended diagnostic criteria for defining DM and IGT according to the World Health Organization. A neighborhood corresponding to a census tract was selected and defined by a map. The 39 blocks encompassed in the neighborhood were identified and randomized using the statistical package Systat. According to the randomization, a complete household enumeration was performed. All the residents and the family relationships were identified. The individuals that were between 35-64 years of age and were not pregnant, were considered eligible and were interviewed at home and invited to have a physical examination with an OGT. The number of inhabitants in the study was 4411 of whom 931 were eligible: 452 (48.5%) men, 479 (51.5%) women. The response rate for the home interview was 91.7%; for the physical examination with the OGT it was 69.8%. The crude rate prevalence of DM for men was 10.6%, and for women it was 14.8%. The crude rate prevalence of IGT for men was 12.8% and 12.3% for women. These results show that susceptibility to DM and IGT is high in our population and are among the highest in the world.