Environmentally Driven Increases in Type 2 Diabetes and Obesity in Pima Indians and Non-Pimas in Mexico Over a 15-Year Period: The Maycoba Project

Effectiveness of a Lifestyle Change Program on Insulin Resistance in Yaquis Indigenous Populations in Sonora, Mexico: PREVISY

To evaluate the effectiveness of the healthy lifestyle promotion program for Yaquis (PREVISY) on insulin resistance in the short- and medium-term periods in adults who are overweight/obese and have an increased risk for diabetes. Using a translational research design, an intervention program was implemented in a sample of 93 Yaqui adult subjects. The effectiveness of PREVISY was evaluated by comparing the levels of Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and the Triglycerides-Glucose Index (TyG index) at 6 and 12 months using a paired t-test. Results: In the subjects who completed the program, a decrease in the HOMA-IR index (∆ = -0.91 and ∆ = -1.29, p ≤ 0.05) and the TyG index (∆ = -0.24 y ∆ = -0.20, p ≤ 0.05) was observed in the short- and medium-term period, respectively. Subjects with body weight loss ≥ 10% showed decreased levels of HOMA-IR (∆ = -3.32 and ∆ = -4.89, p ≤ 0.05) and the TyG index (∆ = -0.80 and ∆ = -0.60, p ≤ 0.05) at 6 and 12 months, respectively. A stronger benefit of the program was found in subjects with obesity (vs. overweight) and with high and very high risk of diabetes (vs. moderate risk) in IR markers (p ≤ 0.05). The PREVISY program demonstrated its effectiveness in the improvement of some markers of insulin resistance in Yaqui adults at risk of diabetes.

Prevalence of overweight, obesity and central obesity and factors associated with BMI in indigenous yaqui people: a probabilistic cross-sectional survey

BACKGROUND

The Yaquis are an Indigenous group who inhabit in the state of Sonora in northwestern Mexico. This group has experienced changes in their lifestyle, moving from a traditional lifestyle to a more modern one, resulting in an increase of obesity and its comorbidities. However, few studies have been done in this group. The aim of this study was to determine the prevalence of overweight, obesity and central obesity and to identify the factors associated with body mass index (BMI) in a representative sample of Indigenous Yaqui people from Sonora, Mexico.

METHODS

A cross-sectional survey with multistage sampling was conducted among adults (N = 351) with residence in Yaqui traditional villages (Vícam, Pótam, Loma de Guamúchil, Loma de Bácum, Tórim, Ráhum, Huiribis or Belem). Anthropometric measurements were taken to diagnose overweight, obesity and central obesity. Food frequency and physical activity (PA) questionnaires designed for the Yaqui population were applied, as well as sociodemographic and clinical history questionnaires. The factors associated with BMI were assessed using multiple linear regression considering the complex design of the sampling.

RESULTS

The prevalence of overweight, obesity and central obesity in the population were 36.5%, 35.0% and 76.0%, respectively. Having higher values of the modernization index (β = 0.20, p = 0.049) was associated with a higher BMI, while having a higher consumption of a "prudent" dietary pattern (traditional dishes, fruits, vegetables and low-fat dairy) (β = -0.58, p = 0.009) and performing a greater number of hours per week of vigorous PA (β = -0.14, p = 0.017) were associated with a lower BMI.

CONCLUSIONS

The prevalence of the studied abnormalities is high. The evidence presented in this study suggests that interventions are needed and more research is required to determine the appropriate components of such interventions, in order to meet the needs of the Yaqui people.

Risk of chronic diseases in indigenous Totonacs from Mexico short running title: Risk of chronic diseases in indigenous Totonacs

AIM

The purpose of this study was to determine the risk of noncommunicable diseases (NCDs) development in four indigenous Totonac communities.

BACKGROUND

Poverty and low education levels increase the risk of unhealthy lifestyles, leading to a higher incidence of NCDs in indigenous communities. In addition, limited access to health services significantly reduces the opportune screening of risk factors.

METHODS

This was a cross-sectional observational study, in which we evaluated the incidence and/or the risk (%) to develop NCDs in adults from indigenous Totonac communities of Puebla State, Mexico. The sample consisted of 255 adults over 20 years old. Analysis of variance (ANOVA), Student's t-test, and Pearson's correlation were used for statistical analysis.

RESULTS

We found significant differences between communities regarding the risk of diabetes (p < 0.05) and hypertension (p < 0.01). However, there were no significant differences in terms of CVD risk (p > 0.05). Men were at higher risk for hypertension and CVD than women (37.8% vs 27.3% and 20.9% vs 12.2%, respectively), whereas women were at a higher risk of diabetes than men based on the FINDRISC score (11.7 vs 9.7, respectively).

CONCLUSION

The Zapotitlan community showed a higher risk of developing both diabetes and hypertension compared with the other communities. Men showed higher risks of hypertension and CVD compared with women. Women are at higher risk of diabetes than men.

Is Obesity/Adiposity-Based Chronic Disease Curable: The Set Point Theory, the Environment, and Second Generation Medications

Adiposity-Based Chronic Disease (ABCD) is a chronic disease and requires life-long treatment and follow-up. Obesity protects obesity through altered regulation of caloric intake and set point mechanisms that maintains a high equilibrium body weight. Lifestyle interventions and obesity medications do not permanently alter the set point which often makes weight loss achieved by lifestyle short-lived and operates to drive weight regain once medications are discontinued. Bariatric surgery procedures can alter appetite and lower the "set point" for equilibrium body weight via unknown mechanisms. However, few patients attain ideal body weight following surgery, many regain weight, and all require long-term follow-up for the disease. The excess adiposity of ABCD gives rise to complications that impair health and confer morbidity and mortality; however, the genetic risks and potential interactions between genes and environment that give rise to complications also cannot be eliminated. The equilibrium body weight around which set point mechanisms operate can be modified by environment, which underscores the importance of a less obesogenic environment for prevention and treatment of ABCD on a population basis. If ABCD will eventually be curable, this will depend on a clear understanding of the molecular mechanisms that determine the set point regulation of body weight, and an ability to permanently modulate the set point to oscillate around and a lean body mass. The conceptualization of ABCD as a chronic disease, however, does present us with opportunities for primary, secondary, and tertiary prevention to avert disease progression. For tertiary care, the advent of new, more effective, second-generation obesity medications will allow clinicians to treat-to-target via active management of body weight into a target range that will ameliorate specific complications.

Risk of developing pre-diabetes or diabetes over time in a cohort of Mexican health workers

Aim

To determine the association between known risk factors (e.g., obesity, metabolic syndrome and its components) and the development of pre-diabetes or diabetes over time in a cohort of Mexican health workers.

Methods

Participants in the Mexican Health Worker Cohort Study with complete information at two waves of data collection, 2004–2006 (W1) and 2011–2013 (W2), were included in the analysis (n = 1,174). Multivariable binary and multinomial logistic regression were used to examine the cross-sectional associations between specific risk factors and diabetes status (diabetes, pre-diabetes, or neither) at W1 and the longitudinal associations between changes in risk factors and progression of diabetes status from W1 to W2, respectively.

Results

Mean time between waves was 7.0 years (SD 1.1). Prevalence of pre-diabetes and diabetes was 16% and 10% at W1 and increased to 30% and 16% at W2, respectively. The cross-sectional prevalence of pre-diabetes and diabetes was significantly higher among men, participants over the age of 45 years, and individuals who were overweight or obese or had metabolic syndrome (MS), three or more components of the MS, elevated alanine aminotransferase (ALT) levels, or elevated uric acid. In longitudinal analyses, remaining obese or gaining weight between waves was associated with an increased risk of developing pre-diabetes. A greater risk of developing pre-diabetes or diabetes was also observed among individuals who either maintained or acquired MS, elevated ALT, or elevated uric acid (only for diabetes) from W1 to W2.

Conclusions

Weight gain and acquiring or maintaining MS, elevated ALT levels, or elevated uric acid were associated with a significant risk of developing pre-diabetes or diabetes. Our findings, especially in the context of the obesity epidemic in Mexico, point towards an urgent need for initiatives to help reduce excess weight in order to avert future cases of pre-diabetes and diabetes.

Effectiveness of the Healthy Lifestyle Promotion Program for Yaquis with Obesity and Risk of Diabetes in the Short and Medium Term: A Translational Study

Type 2 diabetes (T2D) is a public health problem worldwide, and the main risk factor for its development is obesity. The Yaqui ethnic group of Sonora has serious obesity problems, resulting in an increased risk of T2D in its inhabitants. The objective of this study was to evaluate the effectiveness of a health promotion program on obesity parameters and cardiovascular risk factors in short- (6 months) and medium-term periods (12 months) in indigenous Yaquis of Sonora. The design is a translational clinical study of a single cohort with prepost intervention measurements in a sample of 93 subjects. The effectiveness of the program was evaluated by comparing obesity parameters, metabolic markers, and physical activity 6 and 12 months with those measured under basal conditions using a paired t-test or Wilcoxon rank-sum test. The short-term retention percentage was 58.0%. There was a decrease in body weight (Δ = -3.9 kg, p ≤ 0.05) and other obesity parameters, and an increase in physical activity and improvements in metabolic markers (p ≤ 0.05) was observed. Similar findings were obtained for the medium-term period; body weight loss was also -3.9 kg (p ≤ 0.05). The short and medium-term results of the program showed improvements in the obesity parameters and other cardiovascular risk factors of the participants. These results support the effectiveness of the program and its translation in this ethnic group.

Thinness, overweight, and obesity in indigenous school children and youth in Mexico

Background: The prevalence of overweight (OWT) and obesity (OB), defined by the body mass index (BMI, kg/m²) among children and youth has increased worldwide in the last 30-40 years.Aim: To evaluate the weight status, defined by the BMI, of indigenous school children and youth resident in different regions of MexicoSubjects and methods: Students 6-18 years (31,448 boys, 27,306 girls) were enrolled in bilingual schools for indigenous children and youth in Mexico in 2012. Height and weight were measured; the BMI was calculated. The BMI of each student was classified relative to International Obesity Task Force (IOTF) age- and sex-specific criteria as thin (three grades), normal, overweight (OWT) or obese (OB). The sample was divided into five geographic regions for analysis: North, Central, South-Gulf, South-Pacific, and South-Southeast. Age- and sex-specific prevalence, 95% confidence intervals, and Chi-square tests were calculated.Results: Prevalence of OWT + OB was highest in the South-Gulf, South-Pacific and South-Southeast regions and lowest in the North and Central regions, while thinness was most prevalent in the North and Central regions.Conclusion: Prevalence of severe and moderate thinness was relatively low, while the combined prevalence of OWT + OB was generally more prevalent in indigenous boys than girls. However, the prevalence of thinness, OWT + OB among indigenous children and youth was lower than in the general population of children and youth in Mexico.

Disparities in prediabetes and type 2 diabetes prevalence between indigenous and nonindigenous populations from Southeastern Mexico: The Comitan Study

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Indigenous origin conferred lower probability of prediabetes and type 2 diabetes.

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Social determinants were associated with lower probability of type 2 diabetes.

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Family history of diabetes was associated with prediabetes and type 2 diabetes.

Aims

In this research we assessed the prevalence of prediabetes and type 2 diabetes and its association with social determinants such as indigenous origin and residence area in population from Comitan, Chiapas, Mexico.

Methods

The Comitan Study is a population-based study carried out from 2010 to 2012 that included 1844 participants aged ≥ 20 years, 880 indigenous and 964 nonindigenous participants. Ethnicity was ascertained by self-report and speaking an indigenous language was also recorded. Prediabetes was defined as fasting serum glucose 5.6–6.9 mmol/l or 2-hour post load serum glucose 7.8–11.0 mmol/l. Type 2 diabetes was defined as fasting serum glucose ≥ 7.0 mmol/l or 2-h post load serum glucose ≥ 11.1 mmol/l or previous clinical diagnosis.

Results

Age-sex-adjusted prevalence of prediabetes and type 2 diabetes was 18.0% (95%CI 15.3–20.6) and 11.0% (95%CI 8.9–131.1) in nonindigenous and 10.6% (95%CI 8.4–12.7) and 4.7% (95%CI 3.3–6.1) in indigenous individuals, respectively. After stratifying by ethnicity, in both indigenous and nonindigenous participants the probability of prediabetes and type 2 diabetes increased with age and BMI. In both indigenous and nonindigenous participants the probability of type 2 diabetes was lower in those living in rural compared with urban areas.

Conclusions

The prevalence of prediabetes and type 2 diabetes was significantly lower in indigenous than in nonindigenous participants. Also, the prevalence of type 2 diabetes was lower in those living in rural areas. Health benefits of a traditional lifestyle may partially account for these differences.

Early-life origins of disparities in chronic diseases among Indigenous youth: pathways to recovering health disparities from intergenerational trauma

Indigenous women and children experience some of the most profound health disparities globally. These disparities are grounded in historical and contemporary trauma secondary to colonial atrocities perpetuated by settler society. The health disparities that exist for chronic diseases may have their origins in early-life exposures that Indigenous women and children face. Mechanistically, there is evidence that these adverse exposures epigenetically modify genes associated with cardiometabolic disease risk. Interventions designed to support a resilient pregnancy and first 1000 days of life should abrogate disparities in early-life socioeconomic status. Breastfeeding, prenatal care and early child education are key targets for governments and health care providers to start addressing current health disparities in cardiometabolic diseases among Indigenous youth. Programmes grounded in cultural safety and co-developed with communities have successfully reduced health disparities. More works of this kind are needed to reduce inequities in cardiometabolic diseases among Indigenous women and children worldwide.

Analysis of type 2 diabetes and obesity genetic variants in Mexican Pima Indians: Marked allelic differentiation among Amerindians at HLA

Prevalence of diabetes and obesity in Mexican Pima Indians is low, while prevalence in US Pima Indians is high. Although lifestyle likely accounts for much of the difference, the role of genetic factors is not well explored. To examine this, we genotyped 359 single nucleotide polymorphisms, including established type 2 diabetes and obesity variants from genome-wide association studies (GWAS) and 96 random markers, in 342 Mexican Pimas. A multimarker risk score of obesity variants was associated with body mass index (BMI; β = 0.81 kg/m² per SD, P = 0.0066). The mean value of the score was lower in Mexican Pimas than in US Pimas (P = 4.3 × 10^-11 ), and differences in allele frequencies at established loci could account for approximately 7% of the population difference in BMI; however, the difference in risk scores was consistent with evolutionary neutrality given genetic distance. To identify loci potentially under recent natural selection, allele frequencies at 283 variants were compared between US and Mexican Pimas, accounting for genetic distance. The largest differences were seen at HLA markers (e.g., rs9271720, difference = 0.75, P = 8.7 × 10^-9 ); genetic distances at HLA were greater than at random markers (P = 1.6 × 10^-46 ). Analyses of GWAS data in 937 US Pimas also showed sharing of alleles identical by descent at HLA that exceeds its genomic expectation (P = 7.0 × 10^-10 ). These results suggest that, in addition to the widely recognized balancing selection at HLA, recent directional selection may also occur, resulting in marked allelic differentiation between closely related populations.

Integrated analysis of the gene expression profile and DNA methylation profile of obese patients with type 2 diabetes

In order to better understand the etiology of obese type 2 diabetes (T2D) at the molecular level, the present study investigated the gene expression and DNA methylation profiles associated with T2D via systemic analysis. Gene expression (GSE64998) and DNA methylation profiles (GSE65057) from liver tissues of healthy controls and obese patients with T2D were downloaded from the Gene Expression Omnibus database. Differentially-expressed genes (DEGs) and differentially-methylated genes (DMGs) were identified using the Limma package, and their overlapping genes were additionally determined. Enrichment analysis was performed using the BioCloud platform on the DEGs and the overlapping genes. Using Cytoscape software, protein-protein interaction (PPI), transcription factor target networks and microRNA (miRNA) target networks were then constructed in order to determine associated hub genes. In addition, a further GSE15653 dataset was utilized in order to validate the DEGs identified in the GSE64998 dataset analyses. A total of 251 DEGs, including 124 upregulated and 127 downregulated genes, were detected, and a total of 9,698 genes were demonstrated to be differentially methylated in obese patients with T2D compared with non-obese healthy controls. A total of 103 overlapping genes between the two datasets were revealed, including 47 upregulated genes and 56 downregulated genes. The identified overlapping genes were revealed to be strongly associated with fatty acid and glucose metabolic pathways, in addition to oxidation/reduction. The overlapping genes cyclin D1 (CCND1), PPARG coactivator α (PPARGC1A), fatty acid synthase (FASN), glucokinase (GCK), steraroyl-coA desaturase (SCD) and tyrosine aminotransferase (TAT) had higher degrees in the PPI, transcription target networks and miRNA target networks. In addition, among the 251 DEGs, a total of 35 DEGs were validated to be being shared genes between the datasets, which included a number of key genes in the PPI network, including CCND1, FASN and TAT. Abnormal gene expression and DNA methylation patterns that were implicated in fatty acid and glucose metabolic pathways and oxidation/reduction reactions were detected in obese patients with T2D. Furthermore, the CCND1, PPARGC1A, FANS, GCK, SCD and TAT genes may serve a role in the development of obesity-associated T2D.

The Nile Rat (Arvicanthis niloticus) as a Superior Carbohydrate-Sensitive Model for Type 2 Diabetes Mellitus (T2DM)

Type II diabetes mellitus (T2DM) is a multifactorial disease involving complex genetic and environmental interactions. No single animal model has so far mirrored all the characteristics or complications of diabetes in humans. Since this disease represents a chronic nutritional insult based on a diet bearing a high glycemic load, the ideal model should recapitulate the underlying dietary issues. Most rodent models have three shortcomings: (1) they are genetically or chemically modified to produce diabetes; (2) unlike humans, most require high-fat feeding; (3) and they take too long to develop diabetes. By contrast, Nile rats develop diabetes rapidly (8-10 weeks) with high-carbohydrate (hiCHO) diets, similar to humans, and are protected by high fat (with low glycemic load) intake. This review describes diabetes progression in the Nile rat, including various aspects of breeding, feeding, and handling for best experimental outcomes. The diabetes is characterized by a striking genetic permissiveness influencing hyperphagia and hyperinsulinemia; random blood glucose is the best index of disease progression; and kidney failure with chronic morbidity and death are outcomes, all of which mimic uncontrolled T2DM in humans. Non-alcoholic fatty liver disease (NAFLD), also described in diabetic humans, results from hepatic triglyceride and cholesterol accumulation associated with rising blood glucose. Protection is afforded by low glycemic load diets rich in certain fibers or polyphenols. Accordingly, the Nile rat provides a unique opportunity to identify the nutritional factors and underlying genetic and molecular mechanisms that characterize human T2DM.

CARDIOVASCULAR RISK FACTORS IN ADOLESCENTS: ROLE OF INSULIN RESISTANCE AND OBESITY

Introduction

Childhood obesity is a public health problem characterized by early insulin resistance (IR), inflammation, and oxidative stress. The presence of an uninterrupted low-grade inflammatory state impairs metabolic and cardiovascular health. The population is particularly susceptible to develop metabolic disorders related to increased body fat.

Methods

Eighty-three adolescents were recruited and grouped according to HOMA-IR and BMI in either with or without IR and obese or normal-weight respectively. Anthropometric, biochemical, immunological and hormonal variables were determined. Transverse Analytical Study.

Results

Obesity, dyslipidemia, IL-6, and C-reactive protein were significantly higher in the IR group than in the non-IR group. Obese adolescents showed increased insulin levels, HOMA-IR, inflammatory markers, and triglycerides; while having lower HDL-C, and adiponectin when compared to normal-weight adolescents. As expected, obesity-related anthropometric markers positively correlated with IR and inflammatory markers while negatively correlated with adiponectin levels.

Conclusions

Early IR, subclinical inflammation, dyslipidemia, and hypoadiponectinemia characterize obesity in adolescents. These factors may increase the risk of future coronary heart disease (CHD) and diabetes mellitus development (DM) in early adulthood.

Prevalence of prediabetes and modifiable factors in an ethnic group of Mexico: the Comcáac Project

OBJECTIVE

To determine the prevalence of and modifiable factors associated with prediabetes in the Comcáac Indians.

DESIGN

Cross-sectional study where prediabetes was defined using fasting plasma glucose, 2 h plasma glucose and glycated Hb (HbA1c). Physical, anthropometric and biochemical measurements, medical record, socio-economic, dietary and physical activity information were collected. The modifiable factors associated with prediabetes were assessed using multiple logistic regression. Settings Comcáac Indian communities of Punta Chueca and El Desemboque, Sonora, Mexico.

SUBJECTS

Adults (n 227) aged 20 years or older.

RESULTS

The sex- and age-adjusted prevalence (95 % CI) of prediabetes was 47·1 (40·8, 53·5) % in the overall population; age-adjusted prevalence was 47·3 (35·6, 59·0) % in men and 46·7 (39·1, 54·3) % in women. The modifiable factors associated with a risk of prediabetes (OR; 95 % CI) were light-intensity physical activity (per 1 h/week increase: 1·04; 1·01, 1·07) and insulin resistance (homeostasis model assessment of insulin resistance score >6·1 v. <4·1: 4·62; 1·37, 15·51). Increased consumption of a traditional dietary pattern based on fish and seafood, low-fat cereals, fruits and vegetables was a protective factor (0·49; 0·31, 0·79). All variables were modelled together and adjusted for age and sex.

CONCLUSIONS

The high prediabetes prevalence found in the Comcáac community is alarming because it represents a large number of people who are at risk for type 2 diabetes. The identification of modifiable factors associated with prediabetes that are specific to this population may be useful for designing effective strategies to prevent prediabetes.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Environmental/lifestyle factors in the pathogenesis and prevention of type 2 diabetes

BACKGROUND

Environmental and lifestyle changes, in addition to the ageing of populations, are generally believed to account for the rapid global increase in type 2 diabetes prevalence and incidence in recent decades.

DISCUSSION

In this review, we present a comprehensive overview of factors contributing to diabetes risk, including aspects of diet quality and quantity, little physical activity, increased monitor viewing time or sitting in general, exposure to noise or fine dust, short or disturbed sleep, smoking, stress and depression, and a low socioeconomic status. In general, these factors promote an increase in body mass index. Since loss of β-cell function is the ultimate cause of developing overt type 2 diabetes, environmental and lifestyle changes must have resulted in a higher risk of β-cell damage in those at genetic risk. Multiple mechanistic pathways may come into play.

CONCLUSIONS

Strategies of diabetes prevention should aim at promoting a 'diabetes-protective lifestyle' whilst simultaneously enhancing the resistance of the human organism to pro-diabetic environmental and lifestyle factors. More research on diabetes-protective mechanisms seems warranted.

Body composition and susceptibility to type 2 diabetes: an evolutionary perspective

Type 2 diabetes is rapidly increasing in prevalence worldwide, in concert with epidemics of obesity and sedentary behavior that are themselves tracking economic development. Within this broad pattern, susceptibility to diabetes varies substantially in association with ethnicity and nutritional exposures through the life-course. An evolutionary perspective may help understand why humans are so prone to this condition in modern environments, and why this risk is unequally distributed. A simple conceptual model treats diabetes risk as the function of two interacting traits, namely 'metabolic capacity' which promotes glucose homeostasis, and 'metabolic load' which challenges glucose homoeostasis. This conceptual model helps understand how long-term and more recent trends in body composition can be considered to have shaped variability in diabetes risk. Hominin evolution appears to have continued a broader trend evident in primates, towards lower levels of muscularity. In addition, hominins developed higher levels of body fatness, especially in females in relative terms. These traits most likely evolved as part of a broader reorganization of human life history traits in response to growing levels of ecological instability, enabling both survival during tough periods and reproduction during bountiful periods. Since the emergence of Homo sapiens, populations have diverged in body composition in association with geographical setting and local ecological stresses. These long-term trends in both metabolic capacity and adiposity help explain the overall susceptibility of humans to diabetes in ways that are similar to, and exacerbated by, the effects of nutritional exposures during the life-course.

Insulin-sensitive adiposity is associated with a relatively lower risk of diabetes than insulin-resistant adiposity: the Bogalusa Heart Study

Obesity and insulin resistance are both closely associated with type 2 diabetes mellitus (T2DM). It is, however, not clear whether the role of obesity in the development of T2DM is dependent on insulin resistance. This study aims to assess the hypothesis that insulin-sensitive adiposity is associated with a relatively lower risk of T2DM than insulin-resistant adiposity, and the adiposity-T2DM association is modified by insulin resistance in middle-aged black and white adults. The longitudinal study cohort consisted of 1588 middle-aged normoglycemic black and white adults aged 18-44 years at baseline who were followed for 16 years on average. Overweight/obesity at baseline was defined as BMI ≥25, and insulin resistance was measured using the homeostasis model assessment of insulin resistance (HOMA). The prevalence of incident pre-diabetes and T2DM was compared between the insulin-sensitive and insulin-resistant adiposity groups. The prevalence of both incident pre-diabetes and T2DM was higher in the insulin-resistant adiposity than in the insulin-sensitive adiposity group (11.5 vs. 7.5 %, p = 0.023 for pre-diabetes; 16.7 vs. 2.7 %, p < 0.001 for T2DM). In multivariable logistic analyses, adjusted for baseline age, race, sex, follow-up years, and smoking, baseline insulin-resistant obesity was associated with incident pre-diabetes (odds ratio, OR = 2.07, p = 0.046) and T2DM (OR = 8.19, p < 0.001). ORs did not differ between blacks and whites. The ORs for the association of BMI with pre-diabetes and T2DM significantly increased across increasing quartiles of baseline HOMA (p for trend = 0.032 for pre-diabetes and <0.001 for T2DM). Slopes of increasing follow-up glucose with baseline BMI, measured as regression coefficients (β), were significantly greater in insulin-resistant than in insulin-sensitive individuals (β = 0.86 vs. 0.38, p = 0.009 for difference in slopes). These findings suggest that insulin resistance amplifies the obesity-diabetes association and underscore the importance of preventing both adiposity and insulin resistance in young adults.

Ethnic differences in prediabetes and diabetes in the Suriname Health Study

BACKGROUND

Diabetes is increasing worldwide, and information on risk factors to develop targeted interventions is limited. Therefore, we analyzed data of the Suriname Health Study to estimate the prevalence of prediabetes and diabetes. We also explored whether ethnic differences in prediabetes or diabetes risk could be explained by biological, demographic, lifestyle, anthropometric, and metabolic risk factors.

METHOD

The study was designed according to the WHO Steps guidelines. Fasting blood glucose levels were measured in 3393 respondents, aged 15-65 years, from an Amerindian, Creole, Hindustani, Javanese, Maroon or Mixed ethnic background. Prediabetes was defined by fasting blood glucose levels between 6.1 and 7.0 mmol/L and diabetes by fasting blood glucose levels ≥7.0 mmol/L or 'self-reported diabetes medication use.' For all ethnicities, we analyzed sex, age, marital status, educational level, income status, employment, smoking status, residence, physical activity, body mass index, waist circumference, hypertension, and the levels of triglyceride, total cholesterol, high-density lipoprotein-cholesterol and low-density lipoprotein-cholesterol.

RESULTS

The prevalence of prediabetes was 7.4%, while that of diabetes was 13 0%. From these diabetes cases, 39.6% were not diagnosed previously. No ethnic differences were observed in the prevalence of prediabetes. For diabetes, Hindustanis (23.3%) had twice the prevalence compared to other ethnic groups (4.7-14.2%). The associations of the risk factors with prediabetes or diabetes varied among the ethnic groups. The differences in the associations of ethnic groups with prediabetes or diabetes were partly explained by these risk factors.

CONCLUSIONS

The prevalence of diabetes in Suriname is high and most elevated in Hindustanis. The observed variations in risk factors among ethnic groups might explain the ethnic differences between these groups, but follow-up studies are needed to explore this in more depth.