Diabetes mellitus, race, and socioeconomic status. A population-based study

Racial Disparities of Type 2 Diabetes Through Exercise: The Multi-Ethnic Study of Atherosclerosis

INTRODUCTION

Persistent racial and ethnic disparities exist for Type 2 diabetes in the U.S. Racial and ethnic minorities have a higher risk of Type 2 diabetes, and studies suggest that they engage in less exercise than White population. This study examined whether and to what degree racial differences in Type 2 diabetes were explained by exercise.

METHODS

Adults aged 45-84 years without Type 2 diabetes at baseline (2000-2002) were included from the Multi-Ethnic Study of Atherosclerosis cohort and followed through 2020. Associations between race and Type 2 diabetes were examined using multivariable Cox proportional hazard regression. The effects of exercise were assessed using natural mediation effects. Analyses were conducted in 2023.

RESULTS

Controlling for confounders, Hispanic (adjusted hazard ratio [95% CI]=2.02 [1.74, 2.34]), Chinese (1.50 [1.24, 1.82]), and Black (1.66 [1.44, 1.93]) participants had higher Type 2 diabetes risks than White participants. Hispanic (β [SE]= -0.29 [0.04] square root of MET-hour/day, p<0.001) and Chinese (-0.25 [0.04], p<0.001) participants had lower habitual intentional exercise than White participants; this was not true for Black participants (-0.01 [0.03], p=0.85). Habitual intentional exercise explained Type 2 diabetes excess risk by 13.6% for Hispanic and 13.2% for Chinese participants but not for Black participants, compared with that for White participants.

CONCLUSIONS

Habitual intentional exercise accounted for one tenth of the racial differences in Type 2 diabetes when comparing Hispanic or Chinese populations with White populations. Interventions promoting exercise are crucial to decrease Type 2 diabetes risk for all racial groups but may also narrow disparities in Type 2 diabetes among Hispanic and Chinese populations.

Distinct effects of early-stage and late-stage socioeconomic factors on brain and behavioral traits

Socioeconomic status (SES) is a time-varying multidimensional construct with ill-defined dimension-specific and age-specific effects on brain and behavior. We investigated these effects in 4,228 young adults. From 16 socioeconomic indicators, assessed for early (0-10 years) and late (>10 years) stages, we constructed family, provincial, family adverse and neighborhood adverse socioeconomic dimensions. Generally, family SES was associated with brain structure and connectivity along with cognitive function, whereas family adverse and neighborhood adverse SES were associated with personality and emotion. Most associations were observed for both early and late-stage SES; however, adjusting for the effect of early stage SES revealed late-stage-specific SES effects. Changes in SES were associated with personality and cognitive function. Cerebellar and medial frontal volumes and functional connectivity within the left frontoparietal network mediated the associations between family SES and memory and openness. These results inform both more precise interventions for reducing the consequences of adverse SES and experimental designs for excluding confounding socioeconomic effects on human health.

Reversal for metabolic syndrome criteria following the CHANGE program: What are the driving forces? Results from an intervention community-based study

Objective

To examine the impact of the Canadian Health Advanced by Nutrition and Graded Exercise (CHANGE) program on the reversal of one or more metabolic syndrome (MetS) criteria among community members with MetS and define the significant predictors of upholding individual MetS criterion from 2020 to 2023.

Methods

The program enrolled 278 community members with/or at risk of MetS. Participants followed regular physical activity and a Mediterranean diet for 12 months with the assistance of a registered dietitian and a kinesiologist. A licensed practical nurse and/or registered nurse measured participants' weight, height, waist circumference, and blood pressure and withdrew blood samples for laboratory investigations. Physical activity, physical fitness, Mediterranean diet score (MDS), anthropometric measurements, and laboratory investigations were assessed at the baseline and every three months. Descriptive statistics were calculated, and binary logistic regression analysis was performed to define the significant predictors of upholding each criterion of the MetS.

Results

Participants' mean age was 60.5 ± 11.7 years, and 74.8% were females. Participants with MetS decreased by 5.04% by the end of the program. The percentage of participants with each MetS criterion showed a significant decrease at the end of the study, except for low HDL, which remained with no change. Moreover, the mean of physical activity, physical fitness tests, and MDS scores showed a significant increase after the 12 months of study. Compared to baseline, daily sedentary and screen times showed a significant decrease at the end of the program (8.6 vs. 7.2 and 3.2 vs. 2.6 hours, respectively). Logistic regression analysis revealed that age, female gender, low educational attainment, physical activity, physical fitness, and screen time were significant predictors for upholding one or more MetS criteria.

Conclusion

MetS criteria can be reversed following the CHANGE program. Sociodemographic and lifestyle features are significant predictors for upholding MetS criteria. The program is cost-effective considering its low cost and could lead to significant savings on healthcare costs. Further studies among different communities are recommended to confirm the generalizability of the results.

The Risk Of Perpetuating Health Disparities Through Cost-Effectiveness Analyses

Cost-effectiveness analyses are commonly used to inform health care and public health policy decisions. However, standard approaches may systematically disadvantage marginalized groups by incorporating assumptions of persisting health inequities. We examined how competing risks, baseline health care costs, and indirect costs can differentially affect cost-effectiveness analyses for racial and ethnic minority populations. We illustrate that these structural factors can reduce estimated quality-adjusted life-years and cost savings for disadvantaged groups, making interventions focused on disadvantaged populations appear less cost-effective. For example, analyses of a sugar-sweetened beverage tax may estimate higher costs per quality-adjusted life-year gained for Black versus White populations because of differences in competing risks and insurance status that manifest in higher health care cost savings from averted disease among White people. To ensure that cost-effectiveness assessments do not perpetuate inequities, alternative approaches are needed that account for the impact of structural factors on different groups and that consider scenarios in which health inequities are reduced. Sensitivity analyses focusing on health equity could help advance interventions that disproportionately benefit disadvantaged communities.

Epidemiology of fractures in adults of African ancestry with diabetes mellitus: A systematic review and meta-analysis

Diabetes mellitus (DM) is associated with increased fracture risk in White adults. However, the impact of DM on fractures in Black adults is unknown. This systematic review and meta-analysis investigated the association between DM and fractures in adults of African ancestry. MEDLINE, Scopus, CINAHL and Embase databases were searched from their inception up to November 2023 for all studies in the English language investigating the epidemiology of fractures (prevalence, incidence, or risk) in Black men and women (age ≥ 18 years) with type 1 or type 2 DM. Effect sizes for prevalence of previous fractures (%) and incident fracture risk (hazard ratio [HR]) were calculated using a random-effects model on Stata (version 18.0). There were 13 eligible studies, of which 12 were conducted in Black adults from the United States, while one was conducted in adults of West African ancestry from Trinidad and Tobago. We found no fracture data in Black adults with DM living in Africa. Five studies were included in a meta-analysis of incident fracture risk, reporting data from 2926 Black and 6531 White adults with DM. There was increased risk of fractures in Black adults with DM compared to non-DM (HR = 1.65; 95 % confidence interval [CI]: 1.14, 2.39). The risk of fractures was also higher in White adults with DM compared to non-DM (HR = 1.31; 95 % CI: 1.06, 1.61) among these studies. Five studies were included in a meta-analysis of fracture prevalence, of which three also reported fracture prevalence in White adults. There were 175 previous fractures among 993 Black adults with DM and 384 previous fractures among 1467 White adults with DM, with a pooled prevalence of 17.5 % (95 % CI: 15.4, 19.6) and 25.8 % (95 % CI: 4.8, 46.8), respectively. Our results indicate a high burden of fractures in Black adults with DM.

Microglial NF-κB Signaling Deficiency Protects Against Metabolic Disruptions Caused by Volatile Organic Compound via Modulating the Hypothalamic Transcriptome

Prolonged exposure to benzene, a prevalent volatile organic compound (VOC), at concentrations found in smoke, triggers hyperglycemia, and inflammation in mice. Corroborating this with existing epidemiological data, we show a strong correlation between environmental benzene exposure and metabolic impairments in humans. To uncover the underlying mechanisms, we employed a controlled exposure system and continuous glucose monitoring (CGM), revealing rapid blood glucose surges and disturbances in energy homeostasis in mice. These effects were attributed to alterations in the hypothalamic transcriptome, specifically impacting insulin and immune response genes, leading to hypothalamic insulin resistance and neuroinflammation. Moreover, benzene exposure activated microglial transcription characterized by heightened expression of IKKβ/NF-κB-related genes. Remarkably, selective removal of IKKβ in immune cells or adult microglia in mice alleviated benzene-induced hypothalamic gliosis, and protected against hyperglycemia. In summary, our study uncovers a crucial pathophysiological mechanism, establishing a clear link between airborne toxicant exposure and the onset of metabolic diseases.

Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND

Diabetes is one of the leading causes of death and disability worldwide, and affects people regardless of country, age group, or sex. Using the most recent evidentiary and analytical framework from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), we produced location-specific, age-specific, and sex-specific estimates of diabetes prevalence and burden from 1990 to 2021, the proportion of type 1 and type 2 diabetes in 2021, the proportion of the type 2 diabetes burden attributable to selected risk factors, and projections of diabetes prevalence through 2050.

METHODS

Estimates of diabetes prevalence and burden were computed in 204 countries and territories, across 25 age groups, for males and females separately and combined; these estimates comprised lost years of healthy life, measured in disability-adjusted life-years (DALYs; defined as the sum of years of life lost [YLLs] and years lived with disability [YLDs]). We used the Cause of Death Ensemble model (CODEm) approach to estimate deaths due to diabetes, incorporating 25 666 location-years of data from vital registration and verbal autopsy reports in separate total (including both type 1 and type 2 diabetes) and type-specific models. Other forms of diabetes, including gestational and monogenic diabetes, were not explicitly modelled. Total and type 1 diabetes prevalence was estimated by use of a Bayesian meta-regression modelling tool, DisMod-MR 2.1, to analyse 1527 location-years of data from the scientific literature, survey microdata, and insurance claims; type 2 diabetes estimates were computed by subtracting type 1 diabetes from total estimates. Mortality and prevalence estimates, along with standard life expectancy and disability weights, were used to calculate YLLs, YLDs, and DALYs. When appropriate, we extrapolated estimates to a hypothetical population with a standardised age structure to allow comparison in populations with different age structures. We used the comparative risk assessment framework to estimate the risk-attributable type 2 diabetes burden for 16 risk factors falling under risk categories including environmental and occupational factors, tobacco use, high alcohol use, high body-mass index (BMI), dietary factors, and low physical activity. Using a regression framework, we forecast type 1 and type 2 diabetes prevalence through 2050 with Socio-demographic Index (SDI) and high BMI as predictors, respectively.

FINDINGS

In 2021, there were 529 million (95% uncertainty interval [UI] 500-564) people living with diabetes worldwide, and the global age-standardised total diabetes prevalence was 6·1% (5·8-6·5). At the super-region level, the highest age-standardised rates were observed in north Africa and the Middle East (9·3% [8·7-9·9]) and, at the regional level, in Oceania (12·3% [11·5-13·0]). Nationally, Qatar had the world's highest age-specific prevalence of diabetes, at 76·1% (73·1-79·5) in individuals aged 75-79 years. Total diabetes prevalence-especially among older adults-primarily reflects type 2 diabetes, which in 2021 accounted for 96·0% (95·1-96·8) of diabetes cases and 95·4% (94·9-95·9) of diabetes DALYs worldwide. In 2021, 52·2% (25·5-71·8) of global type 2 diabetes DALYs were attributable to high BMI. The contribution of high BMI to type 2 diabetes DALYs rose by 24·3% (18·5-30·4) worldwide between 1990 and 2021. By 2050, more than 1·31 billion (1·22-1·39) people are projected to have diabetes, with expected age-standardised total diabetes prevalence rates greater than 10% in two super-regions: 16·8% (16·1-17·6) in north Africa and the Middle East and 11·3% (10·8-11·9) in Latin America and Caribbean. By 2050, 89 (43·6%) of 204 countries and territories will have an age-standardised rate greater than 10%.

INTERPRETATION

Diabetes remains a substantial public health issue. Type 2 diabetes, which makes up the bulk of diabetes cases, is largely preventable and, in some cases, potentially reversible if identified and managed early in the disease course. However, all evidence indicates that diabetes prevalence is increasing worldwide, primarily due to a rise in obesity caused by multiple factors. Preventing and controlling type 2 diabetes remains an ongoing challenge. It is essential to better understand disparities in risk factor profiles and diabetes burden across populations, to inform strategies to successfully control diabetes risk factors within the context of multiple and complex drivers.

FUNDING

Bill & Melinda Gates Foundation.

Rationale, Design and Participants Baseline Characteristics of a Crossover Randomized Controlled Trial of the Effect of Replacing SSBs with NSBs versus Water on Glucose Tolerance, Gut Microbiome and Cardiometabolic Risk in Overweight or Obese Adult SSB Consumer: Strategies to Oppose SUGARS with Non-Nutritive Sweeteners or Water (STOP Sugars NOW) Trial and Ectopic Fat Sub-Study

BACKGROUND

Health authorities are near universal in their recommendation to replace sugar-sweetened beverages (SSBs) with water. Non-nutritive sweetened beverages (NSBs) are not as widely recommended as a replacement strategy due to a lack of established benefits and concerns they may induce glucose intolerance through changes in the gut microbiome. The STOP Sugars NOW trial aims to assess the effect of the substitution of NSBs (the "intended substitution") versus water (the "standard of care substitution") for SSBs on glucose tolerance and microbiota diversity.

DESIGN AND METHODS

The STOP Sugars NOW trial (NCT03543644) is a pragmatic, "head-to-head", open-label, crossover, randomized controlled trial conducted in an outpatient setting. Participants were overweight or obese adults with a high waist circumference who regularly consumed ≥1 SSBs daily. Each participant completed three 4-week treatment phases (usual SSBs, matched NSBs, or water) in random order, which were separated by ≥4-week washout. Blocked randomization was performed centrally by computer with allocation concealment. Outcome assessment was blinded; however, blinding of participants and trial personnel was not possible. The two primary outcomes are oral glucose tolerance (incremental area under the curve) and gut microbiota beta-diversity (weighted UniFrac distance). Secondary outcomes include related markers of adiposity and glucose and insulin regulation. Adherence was assessed by objective biomarkers of added sugars and non-nutritive sweeteners and self-report intake. A subset of participants was included in an Ectopic Fat sub-study in which the primary outcome is intrahepatocellular lipid (IHCL) by 1H-MRS. Analyses will be according to the intention to treat principle.

BASELINE RESULTS

Recruitment began on 1 June 2018, and the last participant completed the trial on 15 October 2020. We screened 1086 participants, of whom 80 were enrolled and randomized in the main trial and 32 of these were enrolled and randomized in the Ectopic Fat sub-study. The participants were predominantly middle-aged (mean age 41.8 ± SD 13.0 y) and had obesity (BMI of 33.7 ± 6.8 kg/m2) with a near equal ratio of female: male (51%:49%). The average baseline SSB intake was 1.9 servings/day. SSBs were replaced with matched NSB brands, sweetened with either a blend of aspartame and acesulfame-potassium (95%) or sucralose (5%).

CONCLUSIONS

Baseline characteristics for both the main and Ectopic Fat sub-study meet our inclusion criteria and represent a group with overweight or obesity, with characteristics putting them at risk for type 2 diabetes. Findings will be published in peer-reviewed open-access medical journals and provide high-level evidence to inform clinical practice guidelines and public health policy for the use NSBs in sugars reduction strategies.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03543644.

In Utero Maternal Benzene Exposure Predisposes to the Metabolic Imbalance in the Offspring

Environmental chemicals play a significant role in the development of metabolic disorders, especially when exposure occurs early in life. We have recently demonstrated that benzene exposure, at concentrations relevant to cigarette smoke, induces a severe metabolic imbalance in a sex-specific manner affecting male but not female mice. However, the roles of benzene in the development of aberrant metabolic outcomes following gestational exposure, remain largely unexplored. In this study, we exposed pregnant C57BL/6JB dams to benzene at 50 ppm or filtered air for 6 h/day from gestational day 0.5 (GD0.5) through GD21 and studied male and female offspring metabolic phenotypes in their adult life. While no changes in body weight or body composition were observed between groups, 4-month-old male and female offspring exhibited reduced parameters of energy homeostasis (VO2, VCO2, and heat production). However, only male offspring from benzene-exposed dams were glucose intolerant and insulin resistant at this age. By 6 months of age, both male and female offspring exhibited marked glucose intolerance however, only male offspring developed severe insulin resistance. This effect was accompanied by elevated insulin secretion and increased beta-cell mass only in male offspring. In support, Homeostatic Model Assessment for Insulin Resistance, the index of insulin resistance was elevated only in male but not in female offspring. Regardless, both male and female offspring exhibited a considerable increase in hepatic gene expression associated with inflammation and endoplasmic reticulum stress. Thus, gestational benzene exposure can predispose offspring to increased susceptibility to the metabolic imbalance in adulthood with differential sensitivity between sexes.

Ethnic differences in beta cell function occur independently of insulin sensitivity and pancreatic fat in black and white men

INTRODUCTION

It is increasingly recognized that type 2 diabetes (T2D) is a heterogenous disease with ethnic variations. Differences in insulin secretion, insulin resistance and ectopic fat are thought to contribute to these variations. Therefore, we aimed to compare postprandial insulin secretion and the relationships between insulin secretion, insulin sensitivity and pancreatic fat in men of black West African (BA) and white European (WE) ancestry.

RESEARCH DESIGN AND METHODS

A cross-sectional, observational study in which 23 WE and 23 BA men with normal glucose tolerance, matched for body mass index, underwent a mixed meal tolerance test with C peptide modeling to measure beta cell insulin secretion, an MRI to quantify intrapancreatic lipid (IPL), and a hyperinsulinemic-euglycemic clamp to measure whole-body insulin sensitivity.

RESULTS

Postprandial insulin secretion was lower in BA versus WE men following adjustment for insulin sensitivity (estimated marginal means, BA vs WE: 40.5 (95% CI 31.8 to 49.2) × 10³ vs 56.4 (95% CI 48.9 to 63.8) × 10³ pmol/m² body surface area × 180 min, p=0.008). There was a significantly different relationship by ethnicity between IPL and insulin secretion, with a stronger relationship in WE than in BA (r=0.59 vs r=0.39, interaction p=0.036); however, IPL was not a predictor of insulin secretion in either ethnic group following adjustment for insulin sensitivity.

CONCLUSIONS

Ethnicity is an independent determinant of beta cell function in black and white men. In response to a meal, healthy BA men exhibit lower insulin secretion compared with their WE counterparts for their given insulin sensitivity. Ethnic differences in beta cell function may contribute to the greater risk of T2D in populations of African ancestry.

The Need for Ethnoracial Equity in Artificial Intelligence for Diabetes Management: Review and Recommendations

There is clear evidence to suggest that diabetes does not affect all populations equally. Among adults living with diabetes, those from ethnoracial minority communities—foreign-born, immigrant, refugee, and culturally marginalized—are at increased risk of poor health outcomes. Artificial intelligence (AI) is actively being researched as a means of improving diabetes management and care; however, several factors may predispose AI to ethnoracial bias. To better understand whether diabetes AI interventions are being designed in an ethnoracially equitable manner, we conducted a secondary analysis of 141 articles included in a 2018 review by Contreras and Vehi entitled “Artificial Intelligence for Diabetes Management and Decision Support: Literature Review.” Two members of our research team independently reviewed each article and selected those reporting ethnoracial data for further analysis. Only 10 articles (7.1%) were ultimately selected for secondary analysis in our case study. Of the 131 excluded articles, 118 (90.1%) failed to mention participants’ ethnic or racial backgrounds. The included articles reported ethnoracial data under various categories, including race (n=6), ethnicity (n=2), race/ethnicity (n=3), and percentage of Caucasian participants (n=1). Among articles specifically reporting race, the average distribution was 69.5% White, 17.1% Black, and 3.7% Asian. Only 2 articles reported inclusion of Native American participants. Given the clear ethnic and racial differences in diabetes biomarkers, prevalence, and outcomes, the inclusion of ethnoracial training data is likely to improve the accuracy of predictive models. Such considerations are imperative in AI-based tools, which are predisposed to negative biases due to their black-box nature and proneness to distributional shift. Based on our findings, we propose a short questionnaire to assess ethnoracial equity in research describing AI-based diabetes interventions. At this unprecedented time in history, AI can either mitigate or exacerbate disparities in health care. Future accounts of the infancy of diabetes AI must reflect our early and decisive action to confront ethnoracial inequities before they are coded into our systems and perpetuate the very biases we aim to eliminate. If we take deliberate and meaningful steps now toward training our algorithms to be ethnoracially inclusive, we can architect innovations in diabetes care that are bound by the diverse fabric of our society.

Adolescent BMI and early-onset type 2 diabetes among Ethiopian immigrants and their descendants: a nationwide study

BACKGROUND

We assessed in a nationwide cohort the association between adolescent BMI and early-onset (< 40 years) type 2 diabetes among Israelis of Ethiopian origin.

METHODS

Normoglycemic adolescents (range 16-20 years old), including 93,806 native Israelis (≥ 3rd generation in Israel) and 27,684 Israelis of Ethiopian origin, were medically assessed for military service between 1996 and 2011. Weight and height were measured. Data were linked to the Israeli National Diabetes Registry. Incident type 2 diabetes by December 31, 2016 was the outcome. Cox regression models stratified by sex and BMI categories were applied.

RESULTS

226 (0.29%) men and 79 (0.18%) women developed diabetes during 992,980 and 530,814 person-years follow-up, respectively, at a mean age of 30.4 and 27.4 years, respectively. Among native Israeli men with normal and high (overweight and obese) BMI, diabetes incidence was 9.5 and 62.0 (per 105 person-years), respectively. The respective incidences were 46.9 and 112.3 among men of Ethiopian origin. After adjustment for sociodemographic confounders, the hazard ratios for type 2 diabetes among Ethiopian men with normal and high BMI were 3.4 (2.3-5.1) and 15.8 (8.3-30.3) respectively, compared to third-generation Israelis with normal BMI. When this analysis was limited to Israeli-born Ethiopian men, the hazard ratios were 4.4 (1.7-11.4) and 29.1 (12.9-70.6), respectively. Results persisted when immigrants of other white Caucasian origin were the reference; and among women with normal, but not high, BMI.

CONCLUSIONS

Ethiopian origin is a risk factor for early-onset type 2 diabetes among young men at any BMI, and may require selective interventions.

Acarbose protects from central and peripheral metabolic imbalance induced by benzene exposure

Benzene is a well-known human carcinogen that is one of the major components of air pollution. Sources of benzene in ambient air include cigarette smoke, e-cigarettes vaping, and evaporation of benzene containing petrol processes. While the carcinogenic effects of benzene exposure have been well studied, less is known about the metabolic effects of benzene exposure. We show that chronic exposure to benzene at low levels induces a severe metabolic imbalance in a sex-specific manner, and is associated with hypothalamic inflammation and endoplasmic reticulum (ER) stress. Benzene exposure rapidly activates hypothalamic ER stress and neuroinflammatory responses in male mice, while pharmacological inhibition of ER stress response by inhibiting IRE1α-XBP1 pathway significantly alleviates benzene-induced glial inflammatory responses. Additionally, feeding mice with Acarbose, a clinically available anti-diabetes drug, protected against benzene induced central and peripheral metabolic imbalance. Acarbose imitates the slowing of dietary carbohydrate digestion, suggesting that choosing a diet with a low glycemic index might be a potential strategy for reducing the negative metabolic effect of chronic exposure to benzene for smokers or people living/working in urban environments with high concentrations of exposure to automobile exhausts.

NT -pro BNP as a Mediator of the Racial Difference in Incident Atrial Fibrillation and Heart Failure

Background

Blacks harbor more cardiovascular risk factors than whites, but experience less atrial fibrillation (AF). Conversely, whites may have a lower risk of heart failure (CHF). N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) levels are higher in whites, predict incident AF, and have diuretic effects in the setting of increased ventricular diastolic pressures, potentially providing a unifying explanation for these racial differences.

Methods and Results

We used data from the CHS (Cardiovascular Health Study) to determine the degree to which baseline NT‐proBNP levels mediate the relationships between race and incident AF and CHF by comparing beta estimates between models with and without NT‐proBNP. The ARIC (Atherosclerosis Risk in Communities) study was used to assess reproducibility. Among 4731 CHS (770 black) and 12 418 ARIC (3091 black) participants, there were 1277 and 1253 incident AF events, respectively. Whites had higher baseline NT‐proBNP (CHS: 40% higher than blacks; 95% CI, 29–53; ARIC: 39% higher; 95% CI, 33–46) and had a greater risk of incident AF compared with blacks (CHS: adjusted hazard ratio, 1.60; 95% CI, 1.31–1.93; ARIC: hazard ratio, 1.93; 95% CI, 1.57–2.27). NT‐proBNP levels explained a significant proportion of the racial difference in AF risk (CHS: 36.2%; 95% CI, 23.2–69.2%; ARIC: 24.6%; 95% CI, 14.8–39.6%). Contrary to our hypothesis, given an increased risk of CHF among whites in CHS (adjusted hazard ratio, 1.20; 95% CI, 1.05–1.47) and the absence of a significant association between race and CHF in ARIC (adjusted hazard ratio, 1.07; 95% CI, 0.94–1.23), CHF‐related mediation analyses were not performed.

Conclusions

A substantial portion of the relationship between race and AF was statistically explained by baseline NT‐proBNP levels. No consistent relationship between race and CHF was observed.

See Editorial by Richards

Effect of Diabetes Mellitus on Complication Rates of Coronary Artery Bypass Grafting

Previous studies have shown that diabetes mellitus (DM) is a risk factor for postoperative coronary artery bypass grafting (CABG) complications. More contemporary studies are needed to guide revascularization decisions in DM patients. We performed a single-center study of patients who underwent CABG. Patients with no DM were compared with patients with DM, subgrouped according to whether or not DM was treated with insulin before admission (Insulin and No Insulin Groups). Multivariable logistic regression was used to determine whether DM was a significant predictor of mortality, combined postoperative events, and specific postoperative complications after controlling for other predictive clinical variables. Of 11,590 consecutive patients who underwent CABG, 5,013 (43%) had DM and 6,577 (57%) had no DM. Of the patients with DM, 3,433 (68%) were not treated with insulin and 1,580 (32%) were treated with insulin before admission. Multivariable logistic regression analyses showed that DM was not significantly associated with in-hospital mortality or combined postoperative events after considering other clinical variables. The No Insulin Group was significantly associated with stroke, and the Insulin Group was significantly associated with surgical site infection and new renal failure. In conclusion, this study of consecutively treated CABG patients shows that DM is not a predictor of in-hospital mortality or combined in-hospital postoperative events after adjusting for other clinical factors. DM is a predictor of permanent stroke, surgical site infection, and new renal failure. These findings may help with case selection and management of DM patients undergoing CABG.

hs-CRP Is Associated With Incident Diabetic Nephropathy: Findings From the Jackson Heart Study

OBJECTIVE

African Americans (AA) suffer disproportionately from diabetic nephropathy (DN). C-reactive protein (CRP) has been associated with prevalent DN, but its association with incident DN in AA is unknown. We examined hs-CRP and incident DN in AA.

RESEARCH DESIGN AND METHODS

We conducted a longitudinal analysis of data from exams 1, 2, and 3 in 4,043 eligible Jackson Heart Study (JHS) participants. Participants with DN or without hs-CRP at exam 1 were excluded. Incident DN was defined as urinary albumin-to-creatinine ratio (ACR) >30 mg/g or self-reported dialysis/transplantation and type 2 diabetes mellitus (DM) or HbA1c >6.5% by exam 2 or 3 among participants free of DN at exam 1. Kaplan-Meier curves examined DN event-free survival probability by hs-CRP. With Cox proportional hazards regression we estimated hazard ratios (HRs) and 95% CI for DN by hs-CRP tertiles, adjusting for demographics and clinical and laboratory data.

RESULTS

During 7.8 years of median follow-up time, participants who developed DN had significantly higher baseline hs-CRP, age, fasting glucose, triglycerides, ACR, systolic blood pressure, waist circumference, and duration of DM (P < 0.05). The overall incident rate of DN was 7.9%. The mean time to incident DN was shorter for participants with hs-CRP in the high tertile (>4.24 mg/L) than in the low tertile (<1.46 mg/L); P < 0.001. Participants with high hs-CRP had higher incidence of DN (HR 2.34, 95% CI 1.04-5.24) versus the reference group.

CONCLUSIONS

Inflammation, as measured by hs-CRP levels, may be associated with incident DN in AA. Further studies are warranted to replicate and elucidate the basis for this association.

A Systematic Review of Beta Cell Function in Adults of Black African Ethnicity

BACKGROUND

Understanding ethnic differences in beta cell function has important implications for preventative and therapeutic strategies in populations at high risk of type 2 diabetes (T2D). The existing literature, largely drawn from work in children and adolescents, suggests that beta cell function in black African (BA) populations is upregulated when compared to white Europeans (WE).

METHODS

A systematic literature search was undertaken in June 2018 to identify comparative studies of beta cell function between adults (>age 18 years) of indigenous/diasporic BA and WE ethnicity. All categories of glucose tolerance and all methodologies of assessing beta cell function in vivo were included.

RESULTS

41 studies were identified for inclusion into a qualitative synthesis. The majority were studies in African American populations (n = 30) with normal glucose tolerance (NGT)/nondiabetes (n = 25), using intravenous glucose stimulation techniques (n = 27). There were fewer studies in populations defined as only impaired fasting glucose/impaired glucose tolerance (IFG/IGT) (n = 3) or only T2D (n = 3). Although BA broadly exhibited greater peripheral insulin responses than WE, the relatively small number of studies which measured C-peptide to differentiate between beta cell insulin secretion and hepatic insulin extraction (n = 14) had highly variable findings. In exclusively IGT or T2D cohorts, beta cell insulin secretion was found to be lower in BA compared to WE.

CONCLUSIONS

There is inconsistent evidence for upregulated beta cell function in BA adults, and they may in fact exhibit greater deficits in insulin secretory function as glucose intolerance develops.

Genome-wide analysis of DNA methylation in relation to socioeconomic status during development and early adulthood

OBJECTIVES

Socioeconomic status (SES) is a powerful determinant of health, but the underlying biological mechanisms are poorly understood. This study investigates whether levels of DNA methylation at CpG sites across the genome are associated with SES in a cohort of young adults in the Philippines.

METHODS

DNA methylation was assayed with the Illumina HumanMethylation450 Bead Chip, in leukocytes from 489 participants in the Cebu Longitudinal Health and Nutrition Survey (mean age = 20.9 years). SES was measured in infancy/childhood and adulthood, and was based on composite measures of income, assets, and education. Genome-wide analysis of variable probes identified CpG sites significantly associated with SES after adjustment for multiple comparisons. Functional enrichment analysis was used to identify biological pathways associated with these sites.

RESULTS

A total of 2,546 CpG sites, across 1,537 annotated genes, were differentially methylated in association with SES. In comparison with high SES, low SES was associated with increased methylation at 1,777 sites, and decreased methylation at 769 sites. Functional enrichment analysis identified over-representation of biological pathways related to immune function, skeletal development, and development of the nervous system.

CONCLUSIONS

Socioeconomic status predicts DNA methylation at a large number of CpG sites across the genome. The scope of these associations is commensurate with the wide range of biological systems and health outcomes that are shaped by SES, and these findings suggest that DNA methylation may play an important role.

Characteristics of the built environment and spatial patterning of type 2 diabetes in the urban core of Durham, North Carolina

BACKGROUND

Few studies examine relationships between built environment (BE) and type 2 diabetes mellitus (T2DM) using spatial models, investigate BE domains apart from food environment or physical activity resources or conduct sensitivity analysis of methodological choices made in measuring BE. We examine geographic heterogeneity of T2DM, describe how heterogeneity in T2DM relates to BE and estimate associations of T2DM with BE.

METHODS

Individual-level electronic health records (n=41 203) from the Duke Medicine Enterprise Data Warehouse (2007-2011) were linked to BE based on census block. Data on housing damage, property disorder, territoriality, vacancy and public nuisances were used to estimate BE based on four different construction methods (CMs). We used race-stratified aspatial and spatial Bayesian models to assess geographic heterogeneity in T2DM and associations of T2DM with BE.

RESULTS

Among whites, a 1 SD increase in poor quality BE was associated with a 1.03 (95% credible interval 1.01 to 1.06) and 1.06 (95 % credible interval 1.02 to 1.11) increased risk of T2DM for poor quality BE CM1 and CM2, respectively. Among blacks/African Americans, associations between T2DM and BE overlapped with the null for all CMs. The addition of BE to white models reduced residual geographic heterogeneity in T2DM by 4%-15%, depending on CM. In black/African-American models, BE did not affect residual heterogeneity.

CONCLUSION

Associations of T2DM with BE were sensitive to CM and geographic heterogeneity in T2DM differed by race/ethnicity. Findings underscore the need to consider multiple methods of estimating BE and consider differences in relationships by race/ethnicity.

The contribution of health behaviors to socioeconomic inequalities in health: A systematic review

Unhealthy behaviors and their social patterning have been frequently proposed as factors mediating socioeconomic differences in health. However, a clear quantification of the contribution of health behaviors to the socioeconomic gradient in health is lacking. This study systematically reviews the role of health behaviors in explaining socioeconomic inequalities in health. Published studies were identified by a systematic review of PubMed, Embase and Web-of-Science. Four health behaviors were considered: smoking, alcohol consumption, physical activity and diet. We restricted health outcomes to cardiometabolic disorders and mortality. To allow comparison between studies, the contribution of health behaviors, or the part of the socioeconomic gradient in health that is explained by health behaviors, was recalculated in all studies according to the absolute scale difference method. We identified 114 articles on socioeconomic position, health behaviors and cardiometabolic disorders or mortality from electronic databases and articles reference lists. Lower socioeconomic position was associated with an increased risk of all-cause mortality and cardiometabolic disorders, this gradient was explained by health behaviors to varying degrees (minimum contribution -43%; maximum contribution 261%). Health behaviors explained a larger proportion of the SEP-health gradient in studies conducted in North America and Northern Europe, in studies examining all-cause mortality and cardiovascular disease, among men, in younger individuals, and in longitudinal studies, when compared to other settings. Of the four behaviors examined, smoking contributed the most to social inequalities in health, with a median contribution of 19%. Health behaviors contribute to the socioeconomic gradient in cardiometabolic disease and mortality, but this contribution varies according to population and study characteristics. Nevertheless, our results should encourage the implementation of interventions targeting health behaviors, as they may reduce socioeconomic inequalities in health and increase population health.

Glycaemic indices and haemoglobin A1c as predictors for non-healing ulcers

OBJECTIVE

Non-healing lower extremity ulcers (NHLU) are a common podiatric complication of diabetes, with poor glycaemic control as a risk factor for development. Glycaemic indices, such as haemoglobin A1c (HbA1c) and fasting plasma glucose (FPG), are used to diagnose and to monitor diabetes. Using a population-based, nationally representative sample, we evaluate the relationship between glycaemic indices and NHLU (as defined by the patient) to propose glycaemic thresholds for clinical suspicion of patient NHLU status.

METHOD

Using data from the 1999-2004 National Health and Nutrition Examination Surveys (NHANES), a total of 9769 adults (≥40 years old) with available self-reported diabetes and NHLU status were analysed. Glycaemic index markers, including FPG and HbA1c, were assessed via laboratory analysis from serum blood samples. Logistic regression models were fitted to determine optimal thresholds for FPG and HbA1c to predict NHLU status.

RESULTS

Compared with those without NHLU, NHLU patients were older, male, had higher rates of diabetes, were more likely to take insulin, and had lower total cholesterol. Youden's Index for NHLU identified the optimal FPG threshold as 117.7mg/dl (sensitivity: 33.5%; specificity: 82.6%). The optimal HbA1c threshold was 5.9% (sensitivity: 43.2%; specificity: 77.3%). HbA1c (Odds ratio (OR) 2.44, 95% Confidence Interval (CI) 1.96-3.05; Area under curve (AUC) 0.62) was a stronger discriminator of NHLU compared to FPG (OR 2.19; 95%CI 1.57-3.05; AUC 0.60).

CONCLUSION

This study identified glycaemic thresholds for suspicion of NHLU development that are lower than the glucose goal levels recommended as optimal by the American Diabetes Association. Health professionals should be aware of these glycaemic indices when screening patients with diabetes for NHLU. Future longitudinal and validation studies are necessary to better discern the ideal glycaemic index thresholds to identify NHLU.

Characteristics and comorbidities of inpatients without celiac disease on a gluten-free diet

OBJECTIVES

Despite the increasing popularity of gluten-free diet (GFD), the demographic characteristics and medical features of patients without celiac disease on this diet have not been extensively investigated.We aimed to characterize the medical conditions and demographic backgrounds of hospitalized patients without celiac disease who adhere to a GFD, to further understand their reasons for gluten avoidance.

MATERIALS AND METHODS

We performed an observational cohort study on all inpatients at Columbia University Medical Center on a GFD in 2011-2016, excluding those with celiac disease, compared with age-matched and sex-matched inpatients on a regular diet. We determined the odds ratio (OR) of being on a GFD for various comorbidities using conditional logistic regression.

RESULTS

Of 769 inpatients on a GFD, most (63.6%) did not have celiac disease. Gluten-avoiding patients were more likely to be non-Hispanic Whites [OR: 2.92; 95% confidence interval (CI): 2.31-3.70]. They had a lower prevalence of hypertension (OR: 0.38; 95% CI: 0.27-0.52) and diabetes (OR: 0.58; 95% CI: 0.32-0.75) and higher prevalence of inflammatory bowel disease (OR: 1.56; 95% CI: 1.02-2.41), irritable bowel syndrome (OR: 6.16; 95% CI: 2.11-10.23), hyperthyroidism (OR: 2.73; 95% CI: 1.22-6.10), hypothyroidism (OR: 2.06; 95% CI: 1.39-3.06), lupus (OR: 2.87; 95% CI: 1.13-7.29), and autism spectrum disorder (OR: 23.42; 95% CI: 5.29-103.73).

CONCLUSION

Nonceliac gluten-avoiding patients have higher prevalences of inflammatory bowel disease, irritable bowel syndrome, thyroid disease, lupus, and autism spectrum disorder, suggesting patients with these disorders have turned to a GFD for perceived benefit, despite a scant evidence basis.

Prevalence of Type 2 Diabetes Mellitus Among Urban Bihari Communities in Dhaka, Bangladesh: A Cross-sectional Study in a Minor Ethnic Group

Introduction

The prevalence, disease progression, and treatment outcomes for patients with type 2 diabetes vary significantly between ethnic groups. The Bihari community constitutes one of the most vulnerable populations in Bangladesh on the basis of access to health services and other fundamental rights. Our study aimed at finding out the prevalence and risk factors of type 2 diabetes among the Bihari adults in Dhaka city.

Methods

This cross-sectional community-based study was carried out among stranded Pakistanis (known as Bihari) living in camps in the Mirpur area from July 2014 to June 2015. Laboratory-based oral glucose tolerance test (OGTT) was the basis for the diagnosis of type 2 diabetes mellitus (DM). Anthropometric measurements, blood pressure, biochemical tests, family history, and socioeconomic information were obtained to determine the risk factors.

Results

The prevalence of diabetes mellitus (DM), impaired glucose tolerance (IGT), and impaired fasting glucose (IFG) were estimated at 10.11%, 8.74%, and 4.55%, respectively. Increased diastolic blood pressure, serum triglyceride, and cholesterol level were observed to be significantly (p < 0.05) associated with diabetes. Also, the presence of diabetes, high blood pressure, and obesity among relatives significantly increased the probability of diabetes.

Conclusions

To the best of our knowledge, this is the first study on diabetes prevalence among the Bihari community in Bangladesh. The prevalence of type 2 diabetes mellitus was found to be higher among the Bihari community compared to the general population in Bangladesh. Health planners and policymakers should realize the alarming situation and identified risk factors and consider the minor ethnic groups during decision-making regarding prevention and control of diabetes and other noncommunicable diseases.

[Global prevalence of type 2 diabetes mellitus and its relationship with the Human Development IndexPrevalência mundial da diabetes mellitus tipo 2 e sua relação com o índice de desenvolvimento humano]

OBJECTIVE

To evaluate the relationship between the prevalence of type 2 diabetes mellitus (DM2) and the Human Development Index (HDI), by region of the world in the period 2010-2015.

METHOD

International Diabetes Federation data were used for DM2 prevalence (2010-2015), together with HDI data (United Nations Development Program). Spearman linear correlations between HDI data and DM2 prevalence were analyzed, and linear regressions were done to estimate the relationship between the two.

RESULTS

It was observed that lower HDI scores corresponded to lower DM2 prevalence rates, and higher HDI scores to higher DM2 prevalence. At the global level, the HDI explains the 8.6% variance of DM2 prevalence (P < 0.0001) and shows that the situation was different in each region of the world.

CONCLUSIONS

While HDI score may be associated with DM2 prevalence, the relationship between them differs from region to region and from country to country, and depends on the particular year analyzed.

Socioeconomic Disparities in the Prevalence of Cardiometabolic Risk Factors in Ghanaian Women

BACKGROUND

Recent trends toward urbanization in developing countries like Ghana, coupled with nutritional transition and aging populations, have led to a rapid increase in the prevalence of noncommunicable diseases such as obesity, diabetes, and hypertension. The purpose of this study was to evaluate the association between socioeconomic status and cardiometabolic risk factors among women in Ghana.

METHODS

Data for this analysis were obtained from Wave 1 of the Ghana Study of Global Aging and Health, conducted in 2007, and included women 18 years and older. Survey weighted descriptive and multivariable linear regression models were used to examine the association between socioeconomic status and cardiometabolic risk factors.

RESULTS

Among a total of 1988 women, 48% ages 40-64 years, almost half were overweight or obese (47%) and 21% had current hypertension, whereas only 4.3% and 2% of women self-reported a history of hypertension and diabetes, respectively. Multivariable adjusted analysis indicated that women with a high school education had 2-fold increased odds of being overweight or obese compared with those with no formal education (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20-3.42). Women employed in the public sector had almost a 5 times higher odds of being overweight or obese (OR: 4.94, 95% CI: 1.42-17.15), whereas those employed in the private sector or self-employed had reduced odds of diabetes (OR: 0.27, 95% CI: 0.10-0.70) and hypertension (OR: 0.43, 95% CI: 0.21-0.86).

CONCLUSION

The prevalence of cardiometabolic risk factors varies by socioeconomic status among Ghanaian women. Targeted intervention programs to reduce overweight and obesity may begin among Ghanaian women employed in the public sector, and improved access to health care will be critical for timely diagnosis and management of other disease risk factors.

Non-White Race is an Independent Risk Factor for Hospitalization for Aortic Dissection

OBJECTIVE

To evaluate racial differences in the burden of aortic dissection.

DESIGN

Retrospective analysis of a comprehensive state-wide inpatient database.

SETTING

Acute care hospitals in the state of Maryland, 2009 - 2014.

PARTICIPANTS

All hospitalized adults with aortic dissection (AD), stratified by race.

MAIN OUTCOME MEASURES

Statewide and county-level population adjusted hospitalization rates, access to specialty aortic care, and mortality.

RESULTS

Of 3,719,412 admissions to Maryland hospitals during the study period, 3,190 had AD (.09%; 1665 White, 1525 non-White). Non-White race was more common in patients with AD than without (48% vs. 41%, P<.0001). Adjusted for statewide demographics, admission for AD was 1.4 times more common among non-Whites (11 vs. 8 per 100,000, P<.0001). Non-White race was an independent risk factor for AD admission (OR 1.5, 95% CI 1.4 - 1.7). Among patients with AD, non-Whites were younger and more often female, but had similar or lower rates of cardiovascular comorbidities. Non-White race was not associated with decreased access to care or increased mortality.

CONCLUSION

Hospitalization for AD is more common among non-Whites, who develop AD at younger ages despite fewer comorbidities. While clinical correlates are limited from this dataset, this may reflect more severe pathophysiology related to clinical or socioeconomic factors among non-Whites. Further study is warranted to better define this disparity and identify high-risk subgroups who may benefit from aggressive primary prevention.

Prevalence of diabetes mellitus and prediabetes in the adult Romanian population: PREDATORR study

BACKGROUND

The PREDATORR (PREvalence of DiAbeTes mellitus, prediabetes, overweight, Obesity, dyslipidemia, hyperuricemia and chronic kidney disease in Romania) study is the first national study analyzing the prevalence of diabetes mellitus (DM) and prediabetes, and their association with cardiometabolic, sociodemographic, and lifestyle risk factors in the Romanian population aged 20-79 years.

METHODS

This was an epidemiological study with a stratified, cross-sectional, cluster random sampling design. Sociodemographic, lifestyle, and anamnestic data were collected through self- and interviewer-administered questionnaires, and biochemical assays and oral glucose tolerance tests were performed.

RESULTS

In all, 2728 participants from 101 clinics of general practitioners were randomly selected, with a probability proportional to population size according to the 2002 Romanian Census. The participation rate was 99.6%. Impaired glucose regulation (prediabetes, known and unknown DM) was found in 28.1% of the study population. The overall age- and sex-adjusted prevalence of DM was 11.6% (95% CI 9.6%-13.6%), of which 2.4% (95% CI 1.7%-3.1%) had unknown DM. The prevalence of DM increased with age and was higher in men than in women. The age- and sex-adjusted prevalence of prediabetes was 16.5% (95%CI 14.8%-18.2%), with the highest percentage in the 60-79 year age group and in women. Obesity, abdominal obesity, dyslipidemia, low education level, and a family history of diabetes were associated with glucose metabolism disorders.

CONCLUSIONS

The PREDATORR study shows a high prevalence of impaired glucose regulation in the adult Romanian population, providing data on the prevalence of DM and prediabetes and their association with several risk factors.

Sleep as a potential fundamental contributor to disparities in cardiovascular health

Optimal sleep is integral to health but is commonly not obtained. Despite its wide-ranging public health impact, sleep health is considered only rarely by policy makers, employers, schools, and others whose policies and structures can adversely affect sleep. An inadequate duration of sleep and poor-quality sleep are prevalent in minority and low-income populations, and may be fundamental to racial and socioeconomic status inequities that contribute to a range of health conditions, including cardiovascular disease (CVD). This review examines the relationship between sleep and disparities in CVD. We describe the public health importance of sleep and the role of sleep duration, as well as the two most common disorders (sleep apnea and insomnia) as risk factors for a number of chronic diseases. We use a multilevel model focused on population health and health disparities, which is based on the notion that individual behaviors, such as sleep, are influenced by complex and dynamic interrelations among individuals and their physical and social environments. We also describe modifiable factors that contribute to insufficient sleep and circadian misalignment, propose potential interventions in various sectors (e.g., neighborhoods, schools, workplaces) that can address social structures that contribute to disparities, and recommend areas for future research. Integrating sleep into public health research will identify novel approaches for closing gaps in health disparities.

The influence of socioeconomic status on future risk for developing Type 2 diabetes in the Canadian population between 2011 and 2022: differential associations by sex

BACKGROUND

Articulating future risk of diabetes at the population level can inform prevention strategies. While previous studies have characterized diabetes burden according to socioeconomic status (SES), none have studied future risk.

METHODS

We quantified the influence of multiple constructs of SES on future diabetes risk using the Diabetes Population Risk Tool (DPoRT), a validated risk prediction algorithm that generates 10-year rates of new diabetes cases. We applied DPoRT to adults aged 30-64 in the 2011-2012 Canadian Community Health Survey (n = 65,372) and calculated risk for 2021-22. A multi-category outcome was created classifying risk as low (≤5%), moderate (greater than 5% and less than 20%), and high (≥20%), then assessed the impact of individual-level SES indicators, and area-level measures of marginalization on being moderate or high risk using multinomial logistic regression, stratified by sex.

RESULTS

We found nuanced profiles of social determinants by sex, where women are more sensitive to social context. Women living in households where highest educational attainment was less than secondary school were at greater risk [odds ratio (OR) of high compared to low diabetes risk 3.10, 95% confidence interval (CI) 2.19-4.40, p < 0.0001). The same relationship was less pronounced for males (OR 2.17, 95% CI 1.42-3.32, p = 0.0004). Lower household income and being food insecure predicted high future diabetes risk for women (OR 1.37, 95% CI 1.01-1.86, p = 0.0418 comparing quintile 1 to quintile 5; OR 2.64, 95% CI 1.78-3.92, p < 0.0001 comparing severely food insecure to food secure), but not men (OR 1.15, 95% CI 0.84-1.57, p = 0.3818 and OR 1.22, 95% CI 0.71-2.10, p = 0.4815). At the area-level, material deprivation was significantly associated with increased future risk comparing the most to the least deprived (OR females 2.39, 95% CI 1.77-3.23; OR males 1.61, 95% CI 1.22-2.14). Additionally, a strong protective effect was observed for women living in ethnically dense areas (OR 0.75, 95% CI 0.63-0.89, p = 0.0011) which was not as pronounced for men (OR 0.95, 95% CI 0.76-1.18, p = 0.6351).

CONCLUSIONS

This study characterized socio-contextual predictors for future diabetes risk, showing sex-specific effects. Diabetes prevention must consider factors beyond individual-level behavioral lifestyle change and actively take steps to mitigate the adverse impacts of socio-contextual factors.

Undiagnosed Diabetes and Pre-Diabetes in Health Disparities

Globally half of all diabetes mellitus is undiagnosed. We sought to determine the extent and characteristics of undiagnosed type 2 diabetes mellitus and pre-diabetes in Mexican Americans residing in the United States. This disadvantaged population with 50% lifetime risk of diabetes is a microcosm of the current pandemic. We accessed baseline data between 2004 and 2014 from 2,838 adults recruited to our Cameron County Hispanic Cohort (CCHC); a two-stage randomly selected ‘Framingham-like’ cohort of Mexican Americans on the US Mexico border with severe health disparities. We examined prevalence, risk factors and metabolic health in diagnosed and undiagnosed diabetes and pre-diabetes. Two thirds of this Mexican American population has diabetes or pre-diabetes. Diabetes prevalence was 28.0%, nearly half undiagnosed, and pre-diabetes 31.6%. Mean BMI among those with diabetes was 33.5 kg/m² compared with 29.0 kg/m² for those without diabetes. Significant risk factors were low income and educational levels. Most with diabetes had increased waist/hip ratio. Lack of insurance and access to health services played a decisive role in failure to have diabetes diagnosed. Participants with undiagnosed diabetes and pre-diabetes had similar measures of poor metabolic health similar but generally not as severe as those with diagnosed diabetes. More than 50% of a minority Mexican American population in South Texas has diabetes or pre-diabetes and is metabolically unhealthy. Only a third of diabetes cases were diagnosed. Sustained efforts are imperative to identify, diagnose and treat individuals in underserved communities.

Spatial modelling of type II diabetes outcomes: a systematic review of approaches used

With the rising incidence of type II diabetes mellitus (DM II) worldwide, methods to identify high-risk geographical areas have become increasingly important. In this comprehensive review following Cochrane Collaboration guidelines, we outline spatial methods, outcomes and covariates used in all spatial studies involving outcomes of DM II. A total of 1894 potentially relevant citations were identified. Studies were included if spatial methods were used to explore outcomes of DM II or type I and 2 diabetes combined. Descriptive tables were used to summarize information from included studies. Ten spatial studies conducted in the USA, UK and Europe met selection criteria. Three studies used Bayesian generalized linear mixed modelling (GLMM), three used classic generalized linear modelling, one used classic GLMM, two used geographic information systems mapping tools and one compared case:provider ratios across regions. Spatial studies have been effective in identifying high-risk areas and spatial factors associated with DM II outcomes in the USA, UK and Europe, and would be useful in other parts of the world for allocation of additional services to detect and manage DM II early.

Mediators of the association between low socioeconomic status and chronic kidney disease in the United States

Using data collected from 9,823 participants in the 2007-2008 and 2009-2010 cycles of the National Health and Nutrition Examination Survey, we formally investigated potentially modifiable factors linking low socioeconomic status (SES) to chronic kidney disease (CKD) for their presence and magnitude of mediation. SES was defined using the poverty income ratio. The main outcome was CKD, defined as estimated glomerular filtration rate <60 mL/minute/1.73 m(2) (using the Chronic Kidney Disease Epidemiology Collaboration equation) and/or urinary albumin:creatinine ratio ≥30 mg/g. In mediation analyses, we tested the contributions of health-related behaviors (smoking, alcohol intake, diet, physical activity, and sedentary time), comorbid conditions (diabetes, hypertension, obesity, abdominal obesity, and hypercholesterolemia), and access to health care (health insurance and routine health-care visits) to this association. Except for sedentary time and diet, all examined health-related behaviors, comorbid conditions, and factors related to health-care access mediated the low SES-CKD association and contributed 20%, 32%, and 11%, respectively, to this association. In race/ethnicity-specific analyses, identified mediators tended to explain more of the association between low SES and CKD in non-Hispanic blacks than in other racial/ethnic groups. In conclusion, potentially modifiable factors like health-related behaviors, comorbid conditions, and health-care access contribute substantially to the association between low SES and CKD in the United States, especially among non-Hispanic blacks.

Associations Between Diabetes and Cognitive Function in Socioeconomically Diverse African American and White Men and Women

OBJECTIVES

To examine whether race and poverty (income <125% of the federal poverty limit), modifies associations between diabetes and cognition in a biracial, urban-dwelling sample.

METHODS

Cross-sectional data for 2066 participants (mean age = 47.6 years, 56.8% women, 56.2% African American, 38.6% below poverty) from the first wave of the Healthy Aging in Neighborhoods of Diversity across the Life Span study were used for analyses. Eleven tests measured cognitive function. Interactions among diabetes, race, and poverty status with cognition were assessed in multiple regression analyses.

RESULTS

Significant interactions among diabetes, race, and poverty status were observed. Among African Americans below poverty, diabetic individuals performed lower than nondiabetic individuals on California Verbal Learning Test Free Recall Short Delay (z = -0.444 [0.123] versus z = -0.137 [0.045]) and Long Delay (z = -0.299 [0.123] versus z = -0.130 [0.045]), Digit Span Backward (z = -0.347 [0.109] versus z = -0.072 [0.041]), and the Brief Test of Attention (z = -0.452 [-0.099] versus z = -0.099 [0.047]), and higher on Category Fluency (z = 0.114 [0.117] versus z = -0.118 [0.044]). No consistent differences between diabetic and nondiabetic individuals were found for African American and white participants above poverty.

CONCLUSIONS

Diabetes was associated with poorer verbal memory, working memory, and attention among African Americans living in poverty. Diabetic African Americans below poverty may have increased risk of cognitive deficit at a younger age. Improving health literacy, doctor-patient communication, and multidisciplinary medical care for impoverished individuals may reduce differences. Additional research is needed to clarify mechanisms underlying these associations.

Diabetes, Obesity, and the Brain: New Developments in Biobehavioral Medicine

Diabetes and obesity, two major public health concerns, are associated with increased risk for problems in multiple organ systems, including the central nervous system. The adverse effects of diabetes and obesity on cognitive functioning are increasingly well recognized. This special issue of Psychosomatic Medicine features the latest research linking diabetes, obesity, and brain structure, function, and metabolism and follows a special meeting on this topic organized by the American Psychosomatic Society in October 2013. Evidence for the increased prevalence of diabetes and obesity is reviewed as it relates to cognitive decline. These articles indicate that the age of onset of Type 1 diabetes may be relevant to future cognitive function and that disease duration of Type 2 diabetes and sociocultural factors are related to cognitive decline during the aging process. The hypothalamus and other neural circuits, notably the dopaminergic system that underlies feeding and reward-related aspects of food intake, are among the key factors involved in obesity. Research on the associations between obesity and cognitive function is described using the positive effects of weight reduction following bariatric surgery or behavioral methods. This special issue concludes with a conceptual framework for linking obesity and diabetes with accelerated cognitive decline as related to the aging process. The collection of articles highlights the importance of using a life span perspective to understand the influence of both Type 1 and Type 2 diabetes on brain metabolism, function, and structure. Moreover, these studies show that distressing environmental circumstances can adversely influence neurocognitive dysfunction associated with obesity and diabetes.

Weight Loss Programs May Have Beneficial or Adverse Effects on Fat Mass and Insulin Sensitivity in Overweight and Obese Black Women

Objective

Weight loss interventions have produced little change in insulin sensitivity in black women, but mean data may obscure metabolic benefit to some and adverse effects for others. Accordingly, we analyzed insulin sensitivity relative to fat mass change following a weight loss program.

Design and Methods

Fifty-four black women (BMI range 25.9 to 54.7 kg/m²) completed the 6-month program that included nutrition information and worksite exercise facilities. Fat mass was measured by dual-energy X-ray absorptiometry, and insulin sensitivity index (S_I) was calculated from an insulin-modified intravenous glucose tolerance test using the minimal model.

Results

Baseline S_I (range 0.74 to 7.58 l/mU⁻¹•min⁻¹) was inversely associated with fat mass (r = −0.516, p < 0.001), independent of age. On average, subjects lost fat mass (baseline 40.8 ± 12.4 to 39.4 ± 12.6 kg [mean ± SD], P < 0.01), but 17 women (32 %) actually gained fat mass. S_I for the group was unchanged (baseline 3.3 ± 1.7 to 3.2 ± 1.6, P = 0.67). However, the tertile with greatest fat mass loss (−3.6 kg, range −10.7 to −1.7 kg) improved insulin sensitivity (S_I +0.3 ± 1.2), whereas the tertile with net fat mass gain (+0.9 kg, range −0.1 to +3.8 kg) had reduced insulin sensitivity (S_I −0.7 ± 1.3) from baseline values (P < 0.05 by ANOVA).

Conclusions

Black women in a weight loss program who lose fat mass may have improved insulin sensitivity, but fat mass gain with diminished sensitivity is common. Additional support for participants who fail to achieve fat mass loss early in an intervention may be required for success.

Vegetarian diets and incidence of diabetes in the Adventist Health Study-2

AIM

To evaluate the relationship of diet to incident diabetes among non-Black and Black participants in the Adventist Health Study-2.

METHODS AND RESULTS

Participants were 15,200 men and 26,187 women (17.3% Blacks) across the U.S. and Canada who were free of diabetes and who provided demographic, anthropometric, lifestyle and dietary data. Participants were grouped as vegan, lacto ovo vegetarian, pesco vegetarian, semi-vegetarian or non-vegetarian (reference group). A follow-up questionnaire after two years elicited information on the development of diabetes. Cases of diabetes developed in 0.54% of vegans, 1.08% of lacto ovo vegetarians, 1.29% of pesco vegetarians, 0.92% of semi-vegetarians and 2.12% of non-vegetarians. Blacks had an increased risk compared to non-Blacks (odds ratio [OR] 1.364; 95% confidence interval [CI], 1.093-1.702). In multiple logistic regression analysis controlling for age, gender, education, income, television watching, physical activity, sleep, alcohol use, smoking and BMI, vegans (OR 0.381; 95% CI 0.236-0.617), lacto ovo vegetarians (OR 0.618; 95% CI 0.503-0.760) and semi-vegetarians (OR 0.486, 95% CI 0.312-0.755) had a lower risk of diabetes than non-vegetarians. In non-Blacks vegan, lacto ovo and semi-vegetarian diets were protective against diabetes (OR 0.429, 95% CI 0.249-0.740; OR 0.684, 95% CI 0.542-0.862; OR 0.501, 95% CI 0.303-0.827); among Blacks vegan and lacto ovo vegetarian diets were protective (OR 0.304, 95% CI 0.110-0.842; OR 0.472, 95% CI 0.270-0.825). These associations were strengthened when BMI was removed from the analyses.

CONCLUSION

Vegetarian diets (vegan, lacto ovo, semi-) were associated with a substantial and independent reduction in diabetes incidence. In Blacks the dimension of the protection associated with vegetarian diets was as great as the excess risk associated with Black ethnicity.

Renal tissue oxygenation in essential hypertension and chronic kidney disease

Animal studies suggest that renal tissue hypoxia plays an important role in the development of renal damage in hypertension and renal diseases, yet human data were scarce due to the lack of noninvasive methods. Over the last decade, blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), detecting deoxyhemoglobin in hypoxic renal tissue, has become a powerful tool to assess kidney oxygenation noninvasively in humans. This paper provides an overview of BOLD-MRI studies performed in patients suffering from essential hypertension or chronic kidney disease (CKD). In line with animal studies, acute changes in cortical and medullary oxygenation have been observed after the administration of medication (furosemide, blockers of the renin-angiotensin system) or alterations in sodium intake in these patient groups, underlining the important role of renal sodium handling in kidney oxygenation. In contrast, no BOLD-MRI studies have convincingly demonstrated that renal oxygenation is chronically reduced in essential hypertension or in CKD or chronically altered after long-term medication intake. More studies are required to clarify this discrepancy and to further unravel the role of renal oxygenation in the development and progression of essential hypertension and CKD in humans.

Factors that predict frequency of emergency department utilization in children with diabetes-related complaints

OBJECTIVES

The primary purpose of the study was to determine the factors that are associated with repeat emergency department (ED) visits in children with diabetes.

METHODS

Emergency department charts and billing data for children up to 18 years of age presenting to the ED with diabetic diagnoses over a 4-year period were reviewed.

RESULTS

The overall rate of repeat visits to the ED was 0.24 visits per person-year of follow-up time. In univariate analyses, there were statistically significant effects of age, insurance category, sex, type of practice, and income. In a multivariate analysis, there was a significant interaction of insurance category and age. Revisit rate ratios for children older than 6 years were higher for those with Medicaid compared with those with commercial insurance. Diabetic boys were less likely to revisit the ED than were girls.

CONCLUSIONS

Type of insurance was associated with repeated visits to the ED in children with diabetes. Other contributing factors included age group and sex.

Omental gene expression of adiponectin correlates with degree of insulin sensitivity before and after gastric bypass surgery

BACKGROUND

Circulating adiponectin is known to correlate negatively with insulin resistance in patients with obesity and diabetes. The aim of this study was to assess the effect of gastric bypass (GB) surgery on adiponectin gene expression in subcutaneous and omental adipose tissues.

METHODS

Adipose tissues and plasma were obtained from 25 subjects undergoing GB surgery, 15 non-obese subjects, and 12 subjects after GB surgery. Real-time quantitative reverse transcription polymerase chain reaction was used for analysis of the adipose tissues. Adiponectin expression was normalized for glyceraldehyde 3-phosphate dehydrogenase and expressed as percentage of subject-matched subcutaneous expression which was given an arbitrary value of 100%. Insulin resistance was assessed by the homeostatic model assessment (HOMA). Circulating adiponectin was assayed by ELISA.

RESULTS

Omental adiponectin gene expression was fivefold higher in subjects after GB when compared with age-matched morbidly obese subjects before GB (P < 0.01). There were no statistical differences in omental adiponectin gene expression observed in subjects after GB and age-matched non-obese subjects. For the entire cohort of subjects, there was a significant negative correlation between omental adiponectin expression and insulin resistance expressed by HOMA values (r = -0.62, P < 0.001). Circulating adiponectin was significantly lower (P < 0.05) in the obese group than in the non-obese and post-GB groups.

CONCLUSIONS

Omental adiponectin gene expression significantly increases after GB surgery reaching levels equal to age-matched non-obese subjects. Omental adiponectin expression has a significant negative correlation with the insulin resistance status.

Neighborhood deprivation and inequities in coronary heart disease among patients with diabetes mellitus: a multilevel study of 334,000 patients

We used multilevel models to investigate whether the odds of coronary heart disease (CHD) is higher in patients with diabetes mellitus (DM) living in deprived neighborhoods versus those living in wealthy neighborhoods. The Swedish nationwide prescription register was used to identify 334,000 patients aged 30 years and older with DM. The OR of CHD was significantly higher among patients with DM living in deprived neighborhoods than among patients with DM living in wealthy neighborhoods. These findings are useful for clinicians working in deprived neighborhoods. Future research could focus on how to reduce inequities in CHD among patients with DM.

Impact of patient-doctor race concordance on rates of weight-related counseling in visits by black and white obese individuals

The objective of this study was to assess the impact of patient-provider race concordance on weight-related counseling among visits by obese patients. We hypothesized that race concordance would be positively associated with weight-related counseling. We used clinical encounter data obtained from the 2005-2007 National Ambulatory Medical Care Surveys (NAMCS). The sample size included 2,231 visits of black and white obese individuals (ages 20 and older) to their black and white physicians from the specialties of general/family practice and general internal medicine. Three outcome measures of weight-related counseling were explored: weight reduction, diet/nutrition, and exercise. Logistic regression was used to model the outcome variables of interest. Wald tests were used to statistically compare whether physicians of each race provided counseling at different rates for obese patients of different races. We did not observe a positive association between patient-physician race concordance and weight-related counseling. We found that visits by black obese patients to white doctors had a lower odds of exercise counseling as compared to visits by white obese patients to white doctors (odds ratio (OR) = 0.54; 95% confidence interval (CI): 0.31, 0.95), and visits by black obese patients to black physicians had lower odds of receiving weight-reduction counseling than visits among white obese patients seeing black physicians (OR = 0.34; 95% CI: 0.13, 0.90). Black obese patients receive less exercise counseling than white obese patients in visits to white physicians and may be less likely than white obese patients to receive weight-reduction counseling in visits to black physicians.

Excess body mass index-years, a measure of degree and duration of excess weight, and risk for incident diabetes

OBJECTIVE

To evaluate the relation between excess body mass index (BMI)-years, a measure of the degree to which an individual's BMI (calculated as weight in kilograms divided by height in meters squared) exceeds the reference BMI and the duration for which he or she carries excess BMI, and incident diabetes.

DESIGN

Longitudinal analysis.

SETTING

United States of America.

PARTICIPANTS

A total of 8157 adolescents and young adults aged 14 to 21 years at the start of the National Longitudinal Survey of Youth 1979 with self-reported measures of height, weight, and diabetes status (type unspecified) from 1981 through 2006.

MAIN EXPOSURE

Excess BMI-years, which were calculated by subtracting the [corrected] reference BMI (25.0 for adults or 85th percentile for adolescents) from the actual BMI [corrected] for each study year and cumulating excess BMI for the study duration.

MAIN OUTCOME MEASURE

We conducted logistic regression models to predict presumed type 2 diabetes (after excluding presumed type 1 diabetes) as a function of age, sex, race, excess BMI-years, and specific interactions.

RESULTS

A higher level of excess BMI-years was associated with an increased risk of diabetes. For example, on average, white men aged 40 years with 200 excess BMI-years had 2.94 times (95% confidence interval, 2.36-3.67) higher odds of developing diabetes compared with men of the same age and race with 100 excess BMI-years. For a given level of excess BMI-years, younger compared with older and Hispanic and black compared with white individuals had higher risk of developing diabetes. Our study is limited by use of self-reported data without specification of diabetes type.

CONCLUSIONS

Because younger compared with older individuals have a higher risk of self-reported diabetes for a given level of excess BMI-years and cumulative exposure to excess BMI is increasing among younger US birth cohorts, public health interventions should target younger adults.

The impact of disadvantage on the development and progression of diabetic kidney disease

BACKGROUND

Disadvantaged people include those experiencing economic, social or educational deprivation and, in some cases, those undergoing rapid transition from subsistence to industrial economies. Disadvantaged people worldwide are affected disproportionately by the global epidemic of diabetes. They are also at increased risk of kidney disease attributable to diabetes, and for many, the cost of managing their kidney disease far exceeds their available resources.

METHODS

We review factors associated with disadvantage that may increase the risk of diabetic kidney disease, and the barriers to care that hinder attempts to provide an adequate therapeutic response.

RESULTS AND CONCLUSIONS

A rapidly rising prevalence and magnitude of obesity among children and adults, increasing frequency of intrauterine exposure to diabetes, and inadequate access to healthcare are responsible, in part, for a surge in the frequency of diabetes and, in turn, diabetic kidney disease among disadvantaged people. These factors may also predispose to an earlier onset of diabetes and kidney disease, thereby perpetuating the disadvantage by reducing the earning potential of those affected through illness and disability.

Diabetes and the socioeconomic and built environment: geovisualization of disease prevalence and potential contextual associations using ring maps

Background

Efforts to stem the diabetes epidemic in the United States and other countries must take into account a complex array of individual, social, economic, and built environmental factors. Increasingly, scientists use information visualization tools to "make sense" of large multivariate data sets. Recently, ring map visualization has been explored as a means of depicting spatially referenced, multivariate data in a single information graphic. A ring map shows multiple attribute data sets as separate rings of information surrounding a base map of a particular geographic region of interest. In this study, ring maps were used to evaluate diabetes prevalence among adult South Carolina Medicaid recipients. In particular, county-level ring maps were used to evaluate disparities in diabetes prevalence among adult African Americans and Whites and to explore potential county-level associations between diabetes prevalence among adult African Americans and five measures of the socioeconomic and built environment—persistent poverty, unemployment, rurality, number of fast food restaurants per capita, and number of convenience stores per capita. Although Medicaid pays for the health care of approximately 15 percent of all diabetics, few studies have examined diabetes in adult Medicaid recipients at the county level. The present study thus addresses a critical information gap, while illustrating the utility of ring maps in multivariate investigations of population health and environmental context.

Results

Ring maps showed substantial racial disparity in diabetes prevalence among adult Medicaid recipients and suggested an association between adult African American diabetes prevalence and rurality. Rurality was significantly positively associated with diabetes prevalence among adult African American Medicaid recipients in a multivariate statistical model.

Conclusions

Efforts to reduce diabetes among adult African American Medicaid recipients must extend to rural African Americans. Ring maps can be used to integrate diverse data sets, explore attribute associations, and achieve insights critical to the promotion of population health.

Country of birth, socioeconomic factors, and risk factor control in patients with type 2 diabetes: a Swedish study from 25 primary health-care centres

BACKGROUND

Few large-scale studies have examined the association between sociodemographic factors and the probability of reaching the recommended levels of haemoglobin A1c (HbA(1c)) and blood lipids in patients with type 2 diabetes. The aim was to investigate whether sociodemographic characteristics of patients with type 2 diabetes affected the odds that they would reach recommended levels of blood lipids and HbA(1c).

METHODS

This study included 2912 men and 2136 women, in the age group of 35-74, with diagnosed type 2 diabetes from 25 primary health-care centres in Stockholm, Sweden. National population registers were linked to clinical data from electronic records and logistic regression was used to estimate odds ratios.

RESULTS

Less than half of the men and women with diabetes reached the recommended levels of HbA(1c). Even fewer reached the recommended levels for total cholesterol and low-density lipoprotein cholesterol. The gender differences favoured women, for HbA(1c) and men, for blood lipids. Individuals with the lowest income levels were less likely to reach the recommended level of HbA(1c). Country of birth showed that immigrants from Middle Eastern countries and other countries had lower odds of reaching the recommended levels of HbA(1c).

CONCLUSION

This study confirmed that risk factor control among patients with type 2 diabetes treated in primary health care is inadequate and that sociodemographic factors were associated with metabolic control. Future studies could include new strategies for the control of modifiable risk factors in patients with type 2 diabetes.

Gestational diabetes history may signal deprivation in women with type 2 diabetes

BACKGROUND

There is a higher prevalence of type 2 diabetes in lower income groups, particularly in women. Gestational diabetes (diabetes during pregnancy) has also been associated with lower income levels. What has not been studied is whether a past history of gestational diabetes retains an inverse association with income among women with type 2 diabetes.

METHODS

Among women with type 2 diabetes, we assessed for an association between history of gestational diabetes and lower income/lower educational attainment (multiple waves of Canadian Community Health Survey [CCHS]) through logistic regression models adjusted for age, body mass index (BMI), immigrant and marital status, smoking history, and physical activity.

RESULTS

Compared to women in the highest income group, a gestational diabetes history was 71% more likely in the lower middle income group (odds ratio [OR] 1.71, 95% confidence interval [CI] 1.06-2.74) and nearly two times more likely in the lowest income group (OR 1.94, 95% CI 1.15-3.27). Associations with education were inconclusive. Compared to married women, single women (divorced/separated/never married) were nearly two times more likely to have a gestational diabetes history (OR 1.71, 95% CI 1.17-2.49).

CONCLUSIONS

These findings indicate that women with diabetes and past history of gestational diabetes constitute a particularly deprived group. A gestational diabetes history in women with type 2 diabetes may signal a need to assess and address material resources and social support as part of the diabetes management plan.

Racial differences in diabetes-related psychosocial factors and glycemic control in patients with type 2 diabetes

BACKGROUND

We examined whether diabetes-related psychosocial factors differ between African American and white patients with type 2 diabetes. We also tested whether racial differences in glycemic control are independent of such factors.

METHODS

Baseline glycosylated hemoglobin (HbA(1c)) and survey measures from 79 African American and 203 white adult participants in a diabetes self-management clinical trial were analyzed.

RESULTS

Several psychosocial characteristics varied by race. Perceived interference of diabetes with daily life, perceived diabetes severity, and diabetes-related emotional distress were higher for African Americans than for whites, as were access to illness-management resources and social support. Mean HbA(1c) levels were higher among African Americans than whites (8.14 vs 7.40, beta = 0.17). This difference persisted after adjusting for demographic, clinical, and diabetes-related psychosocial characteristics that differed by race (beta = 0.18). Less access to illness-management resources (beta = -0.25) and greater perceived severity of diabetes (beta = 0.21) also predicted higher HbA(1c).

DISCUSSION

Although racial differences in diabetes-related psychosocial factors were observed, African Americans continued to have poorer glycemic control than whites even after such differences were taken into account. Interventions that target psychosocial factors related to diabetes management, particularly illness-management resources, may be a promising way to improve glycemic control for all patients.