Increased Risk Of Type 2 Diabetes Research Articles

Exposure to food additive mixtures and type 2 diabetes risk in the NutriNet-Santé cohort

Abstract Background So far, the safety evaluation of food additives has been performed substance by substance, while in real life, millions of individuals are exposed to mixtures of food additives daily. According to preliminary experimental data, some of these chemicals, alone and/or in synergy are suspected to impact metabolic health. The objective of this study was to investigate for the first time the associations between exposure to mixtures of food additives and type 2 diabetes (T2D) risk in a large prospective cohort of French adults. Methods Participants (n = 108,783, 79.2% women, mean age=42.4 years, SD = 14.6) from the NutriNet-Santé cohort (2009-2024) completed repeated 24h-dietary records, detailing industrial product brands. Additive exposure was assessed using composition databases and laboratory assays. Five mixtures of additives were identified through non-negative matrix factorisation (NMF). Associations between these mixtures and the risk of T2D were characterised using multivariable proportional hazards Cox models adjusted for known risk factors. Findings 1115 participants were identified with T2D during follow-up. Two additive mixtures were associated with increased T2D risk. The first mixture included higher exposure to modified starches E14xx, pectins E440, guar gum E412, carrageenan E407, and polyphosphates E452 (HRper 1SD increment=1.11 [1.05-1.18]), p < 0.0001). The second mixture comprised citric acid E330, sodium citrates E331, phosphoric acid E338, sulphite ammonia caramel E150d, acesulfame-K E950, aspartame E951, sucralose E955 and arabic gum E414 (HR1SD=1.13 [1.08-1.18]), p < 0.0001). Interpretation This large prospective cohort study revealed direct associations between T2D risk and exposure to two food additive mixtures. Molecular epidemiology and experimental studies will be necessary to depict underlying mechanisms and potential cocktail effects. Key messages • Consumed together, widely used food additives may contribute to T2D aetiology, shedding light on the detrimental impact of highly processed foods on metabolic health. • This study highlights positives associations between T2D risk and exposure to two food additive mixtures.

Risk of type-2-diabetes after breast cancer treatment: a population-based cohort study in Denmark.

Data on type 2 diabetes (T2D) risk after breast cancer (BC) could guide preventive strategies. Yet, studies had limitations regarding sample size, follow-up, and contemporary treatments. We evaluated the risk of T2D after BC overall, by cancer treatment, and compared with a matched cohort of cancer-free women. We assembled a population-based cohort of early-stage BC patients aged ≥30 years diagnosed during 1996-2021 in Denmark. We created a comparison cohort of five cancer- and T2D-free women for each BC case, matched six months after BC diagnosis date on age and region. We followed both cohorts until T2D diagnosis, emigration, death, or December 31, 2022. We computed 5-year cumulative incidences and used Cox models to calculate time-varying adjusted hazard ratios (aHR) of T2D. Among 74,526 BC survivors and 372,630 matched cancer-free women, 5-year cumulative incidences of T2D were 3.8% (95%CI = 3.7-3.9) and 3.3% (95%CI = 3.3-3.4), respectively. The aHR of T2D was elevated but attenuated over follow-up (aHR5-years=1.20, 95%CI = 1.15-1.25, and aHR15-years=1.09, 95%CI = 1.05-1.12). Adjuvant endocrine therapy (aHR = 1.14; 95%CI = 1.10-1.19), aromatase inhibitors (aHR = 1.25; 95%CI = 1.18-1.32), and less so tamoxifen (aHR = 1.05; 95%CI = 0.99-1.11), were associated with elevated risk of T2D in women with BC vs cancer-free women. Among BC patients, chemotherapy (aHR = 1.10, 95%CI = 1.03-1.17) and radiation therapy (right-sided aHR = 1.18, 95%CI = 1.09-1.27 and left-sided aHR = 1.24, 95%CI = 1.15-1.33) were associated with increased T2D risk. BC was associated with excess risk of T2D, though of lower magnitude than previously reported. The excess risk was temporary and related to BC treatment but could also be influenced by obesity and heightened T2D diagnostic activity.

NADPH oxidase 5 is a novel susceptibility gene for type 2 diabetes mellitus.

This pilot study investigated whether single nucleotide polymorphisms (SNP) in the NOX5 gene (NADPH oxidase 5) are associated with the type 2 diabetes (T2D) risk. A total of 1579 patients with T2D and 1627 age- and sex-matched healthy subjects were recruited for this study. Genotyping of common SNPs, namely rs35672233, rs3743093, rs2036343, rs311886, and rs438866, was performed using the MassArray-4 system. SNP rs35672233 was associated with an increased risk of T2D (OR = 1.67, 95% CI 1.29-2.17, FDR = 0.003). The H3 haplotype (rs35672233T-rs3743093G-rs2036343A-rs311886C-rs438866C) increased T2D risk (OR = 1.65, 95% CI 1.27-2.13, FDR = 0.001). The rs35672233 polymorphism and H3 haplotype were found to have an association with T2D risk only in subjects with a body mass index greater than 25 kg/m2 (FDR < 0.01). Environmental risk factors, such as chronic psycho-emotional stress, sedentary lifestyle, high-calorie diet and SNP rs35672233 were jointly associated with T2D susceptibility. A haplotype comprising the allele rs35672233-C and conferring protection against T2D, was associated with elevated levels of antioxidants such as total glutathione and uric acid, as well as reduced levels of two-hour postprandial glucose in the plasma of patients. The NOX5 polymorphisms showed no associations with diabetic complications. The present study is the first to establish associations between polymorphisms in NOX5 and the risk of type 2 diabetes mellitus, and provides a new line of evidence for the crucial role of oxidative stress-related genes in disease susceptibility.

Rare variant analyses in 51,256 type 2 diabetes cases and 370,487 controls reveal the pathogenicity spectrum of monogenic diabetes genes

Type 2 diabetes (T2D) genome-wide association studies (GWASs) often overlook rare variants as a result of previous imputation panels’ limitations and scarce whole-genome sequencing (WGS) data. We used TOPMed imputation and WGS to conduct the largest T2D GWAS meta-analysis involving 51,256 cases of T2D and 370,487 controls, targeting variants with a minor allele frequency as low as 5 × 10−5. We identified 12 new variants, including a rare African/African American-enriched enhancer variant near the LEP gene (rs147287548), associated with fourfold increased T2D risk. We also identified a rare missense variant in HNF4A (p.Arg114Trp), associated with eightfold increased T2D risk, previously reported in maturity-onset diabetes of the young with reduced penetrance, but observed here in a T2D GWAS. We further leveraged these data to analyze 1,634 ClinVar variants in 22 genes related to monogenic diabetes, identifying two additional rare variants in HNF1A and GCK associated with fivefold and eightfold increased T2D risk, respectively, the effects of which were modified by the individual’s polygenic risk score. For 21% of the variants with conflicting interpretations or uncertain significance in ClinVar, we provided support of being benign based on their lack of association with T2D. Our work provides a framework for using rare variant GWASs to identify large-effect variants and assess variant pathogenicity in monogenic diabetes genes.

Thyroid Function, Diabetes, and Common Age-Related Eye Diseases: A Mendelian Randomization Study.

Background: Previous Mendelian randomization (MR) studies showed an association between hypothyroidism and cataract and between high-normal free thyroxine (FT4) and late age-related macular degeneration (AMD), but not between FT4, thyroid stimulating hormone (TSH), or hyperthyroidism and diabetic retinopathy or cataract. These studies included a limited number of genetic variants for thyroid function and did not investigate autoimmune thyroid disease (AITD) or glaucoma, include bidirectional and multivariable MR (MVMR), and examine sex differences or potential mediation effects of diabetes. We aimed to address this knowledge gap. Methods: We examined the causality and directionality of the associations of AITD, and FT4 and TSH within the reference range with common age-related eye diseases (diabetic retinopathy, cataract, early and late AMD, and primary open-angle glaucoma). We conducted a bidirectional two-sample MR study utilizing publicly available genome-wide association study (GWAS) summary statistics from international consortia (ThyroidOmics, International AMD Genetics Consortium, deCODE, UK Biobank, FinnGen, and DIAGRAM). Bidirectional MR tested directionality, whereas MVMR estimated independent causal effects. Furthermore, we investigated type 1 diabetes (T1D) and type 2 diabetes (T2D) as potential mediators. Results: Genetic predisposition to AITD was associated with increased risk of diabetic retinopathy (p = 3 × 10-4), cataract (p = 3 × 10-3), and T1D (p = 1 × 10-3), but less likely T2D (p = 0.01). MVMR showed attenuated estimates for diabetic retinopathy and cataract when adjusting for T1D, but not T2D. We found pairwise bidirectional associations between AITD, T1D, and diabetic retinopathy. Genetic predisposition to both T1D and T2D increased the risk of diabetic retinopathy and cataract (p < 4 × 10-4). Moreover, genetically predicted higher FT4 within the reference range was associated with an increased risk of late AMD (p = 0.01), particularly in women (p = 7 × 10-3). However, we neither found any association between FT4 and early AMD nor between TSH and early and late AMD. No other associations were observed. Conclusions: Genetic predisposition to AITD is associated with risk of diabetic retinopathy and cataract, mostly mediated through increased T1D risk. Reciprocal associations between AITD, diabetic retinopathy, and T1D imply a shared autoimmune origin. The role of FT4 in AMD and potential sex discrepancies needs further investigation.

Genetic Associations of Lipids and Lipid-Modifying Drug Targets With Type 2 Diabetes in the Chinese Population

BackgroundDyslipidemia is a recognized risk factor for type 2 diabetes (T2D), yet the genetic basis and causal nature remain unclear, particularly in Chinese populations. ObjectivesThe authors investigated the causal effects of genetically predicted lipid levels on T2D risk and explored the potential effects of lipid-modifying drugs. MethodsLeveraging data from the Kunshan Community cohort in China, we analyzed the associations between low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, and triglycerides (TGs) with T2D risk using genetic risk scores, 1-sample univariable, multivariable, and nonlinear Mendelian randomization (MR) analyses. Two-sample MR using summary-level data from Global Lipid Genetics Consortium and Biobank Japan was used for validation. Drug-target MR was used to examine the impact of lipid-modifying drug targets on T2D. ResultsLower genetic risk scores of LDL-C (OR per SD: 0.97 [95% CI: 0.95-0.99]; P = 0.010) and TGs (0.96 [95%CI: 0.94-0.98]; P = 0.002) were associated with increased T2D risk. Univariable MR revealed that genetically predicted lower LDL-C (0.78 [95% CI: 0.65-0.93]; P = 0.006) and TG levels (0.76 [95% CI: 0.66-0.89]; P < 0.001) were linked to a higher T2D risk, validated by 2-sample MR. Multivariable MR demonstrated a direct inverse association between LDL-C (0.80 [95% CI: 0.66-0.97]; P = 0.020) and TG (0.80 [95% CI: 0.66-0.97]; P = 0.022) with T2D. No evidence was found for nonlinearity. Among lipid-modifying drugs, genetic mimicry of apolipoprotein C3 (APOC3) inhibition increased T2D risk (OR per 1 mmol/L reduction in TG: 1.38 [95% CI: 1.10-1.75]; P = 0.007). ConclusionsOur findings suggested potential adverse effects of lower LDL-C, TG levels, as well as long-term use of APOC3 inhibitors on T2D risk in Chinese populations. These findings highlight the need for cautious lipid management strategies in T2D prevention.

Association of Dietary Selenium Intake with Type 2 Diabetes in Middle-Aged and Older Adults in China.

The relationship between distinct dietary selenium intake and type 2 diabetes (T2D) is still a topic of uncertainty. This study examined the relationship between dietary selenium intake and T2D risk among middle-aged and older Chinese adults. Dietary selenium intake was assessed through three 24 h recalls, using data from the China Health and Nutrition Survey. To investigate the relationship and the potential dose-response pattern between selenium intake and the likelihood of developing T2D, we employed both the restricted cubic spline analysis and the Cox proportional hazards model as our analytical tools. A cohort of 5970 participants aged ≥ 50 years was followed for an average of 5.44 years. The results revealed a V-shaped correlation between selenium intake and T2D risk, with the lowest risk observed at approximately 45 µg/day. Below this level, the risk decreased with an increasing selenium intake, while the risk increased between 45 and 100 µg/day. No significant association was found beyond 100 µg/day. These findings suggest that both low and high selenium consumption may increase T2D risk, highlighting the importance of maintaining a balanced selenium intake for T2D prevention.

Identification and correction for collider bias in a genome-wide association study of diabetes-related heart failure

Type 2 diabetes (T2D) is a major risk factor for heart failure (HF) and has elevated incidence among individuals with HF. Since genetics and HF can independently influence T2D, collider bias may occur when T2D (i.e., collider) is controlled for by design or analysis. Thus, we conducted a genome-wide association study (GWAS) of diabetes-related HF with correction for collider bias. We first performed a GWAS of HF to identify genetic instrumental variables (GIVs) for HF and to enable bidirectional Mendelian randomization (MR) analysis between T2D and HF. We identified 61 genomic loci, significantly associated with all-cause HF in 114,275 individuals with HF and over 1.5 million controls of European ancestry. Using a two-sample bidirectional MR approach with 59 and 82 GIVs for HF and T2D, respectively, we estimated that T2D increased HF risk (odds ratio [OR] 1.07, 95% confidence interval [CI] 1.04-1.10), while HF also increased T2D risk (OR 1.60, 95% CI 1.36-1.88). Then we performed a GWAS of diabetes-related HF corrected for collider bias due to the study design of index cases. After removing the spurious association of TCF7L2 locus due to collider bias, we identified two genome-wide significant loci close to PITX2 (chromosome 4) and CDKN2B-AS1 (chromosome 9) associated with diabetes-related HF in the Million Veteran Program and replicated the associations in the UK Biobank. Our MR findings provide strong evidence that HF increases T2D risk. As a result, collider bias leads to spurious genetic associations of diabetes-related HF, which can be effectively corrected to identify true positive loci.

Association between liver enzymes and type 2 diabetes: a real-world study.

This study aimed to examine the association of liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl-transferase (GGT), with type 2 diabetes (T2D) risk, particularly their dose-response relationship. This cross-sectional study enrolled participants aged >20 years old who underwent physical examination at our local hospital from November 2022 to May 2023. A generalized additive model (GAM) was fit to assess the dose-response relationship between liver enzymes and T2D risk. Furthermore, data from the UK Biobank (n=217,533) and National Health and Nutrition Examination Survey (NHANES 2011-2018; n= 15,528) were analyzed to evaluate whether the dose-response relationship between liver enzymes and T2D differed by population differences. A total of 14,100 participants were included (1,155 individuals with T2D and 12,945 individuals without diabetes) in the analysis. GAM revealed a non-linear relationship between liver enzymes and T2D risk (P non-linear < 0.001). Specifically, T2D risk increased with increasing ALT and GGT levels (range, <50 IU/L) and then plateaued when ALT and GGT levels were >50 IU/L. Elevated AST within a certain range (range, <35 IU/L) decreased the risk of T2D, whereas mildly elevated AST (>35 IU/L) became a risk factor for T2D. The UK Biobank and NHANES data analysis also showed a similar non-linear pattern between liver enzymes and T2D incidence. Liver enzymes were non-linearly associated with T2D risk in different populations, including China, the UK, and the US. Elevated ALT and GGT levels, within a certain range, could increase T2D risk. More attention should be given to liver enzyme levels for early lifestyle intervention and early T2D prevention. Further studies are necessary to explore the mechanism of the non-linear association between liver enzymes and T2D risk.

Exploring the role of purinergic receptor P2RY1 in type 2 diabetes risk and pathophysiology: Insights from human functional genomics

ObjectiveHuman functional genomics has proven powerful in discovering drug targets for common metabolic disorders. Through this approach, we investigated the involvement of the purinergic receptor P2RY1 in type 2 diabetes (T2D). MethodsP2RY1 was sequenced in 9,266 participants including 4,177 patients with T2D. In vitro analyses were then performed to assess the functional effect of each variant. Expression quantitative trait loci (eQTL) analysis was performed in pancreatic islets from 103 pancreatectomized individuals. The effect of P2RY1 on glucose-stimulated insulin secretion was finally assessed in human pancreatic beta cells (EndoCβH5), and RNA sequencing was performed on these cells. ResultsSequencing P2YR1 in 9,266 participants revealed 22 rare variants, seven of which were loss-of-function according to our in vitro analyses. Carriers, except one, exhibited impaired glucose control. Our eQTL analysis of human islets identified P2RY1 variants, in a beta-cell enhancer, linked to increased P2RY1 expression and reduced T2D risk, contrasting with variants located in a silent region associated with decreased P2RY1 expression and increased T2D risk. Additionally, a P2RY1-specific agonist increased insulin secretion upon glucose stimulation, while the antagonist led to decreased insulin secretion. RNA-seq highlighted TXNIP as one of the main transcriptomic markers of insulin secretion triggered by P2RY1 agonist. ConclusionOur findings suggest that P2RY1 inherited or acquired dysfunction increases T2D risk and that P2RY1 activation stimulates insulin secretion. Selective P2RY1 agonists, impermeable to the blood–brain barrier, could serve as potential insulin secretagogues.

Sex differences in type 2 diabetes genetic susceptibility

Introduction. In the last few years gender and sex differences in type 2 diabetes (T2D) predisposition are paid much attention. This gap can be caused by the hormonal and genetic background and require further traits.Aim. The aim of this study was to identify genetic markers of T2D predisposition depending on sex using 17 polymorphic markers of genes involved in various links of T2D pathogenesis.Material and Methods. 536 patients with T2D and 1,476 healthy individuals were examined. Amplification of 17 polymorphic gene loci was performed by polymerase chain reaction. Associations of DNA polymorphisms with T2D were evaluated by logistic regression using the SNPStats program. The degree of association was assessed in the odds ratio (OR) scores. Correction for multiplicity of comparisons and multivariate analysis was used.Results. The genotypes of increased T2D risk for men are CC of CCL20 rs6749704 marker (OR = 3.85, P = 0.0002) in recessive model, D/I of CCR5 rs333 marker (OR = 4.42, P = 0.0208); by GRIA1 marker rs2195450 - CT and TT in the dominant model (OR = 2.42, P = 0.0002), TT - in the recessive model (OR = 2.89, P = 0.0070). The genotypes of increased risk of T2D in women according to the marker TCF7L2 rs7903146 - CT and TT in the dominant model (OR = 1.69, P = 0.0003), TT - in recessive (OR = 1.61, P = 0.0124), according to the marker ADIPOQ rs17366743 - TC (OR = 2.55, P = 0.0168).Conclusion. The established genotypes of increased T2D risk depending on gender make it possible to personalize approaches to primary T2D prevention.

Vaspin: A Novel Biomarker Linking Gluteofemoral Body Fat and Type 2 Diabetes Risk.

To determine whether adiposity depots modulate vaspin levels and whether vaspin predicts type 2 diabetes (T2D) risk, through epidemiological and genetic analyses. We assessed the relationship of plasma vaspin concentration with incident and prevalent T2D and adiposity-related variables in 1) the Prospective Urban and Rural Epidemiology (PURE) biomarker substudy (N = 10,052) and 2) the Outcome Reduction with Initial Glargine Intervention (ORIGIN) trial (N = 7,840), using regression models. We then assessed whether vaspin is causally associated with T2D and whether genetic variants associated with MRI-measured adiposity depots modulate vaspin levels, using two-sample Mendelian randomization (MR). A 1-SD increase in circulating vaspin levels was associated with a 16% increase in incident T2D in the PURE cohort (hazard ratio 1.16; 95% CI 1.09-1.23; P = 4.26 × 10-7) and prevalent T2D in the ORIGIN cohort (odds ratio [OR] 1.16; 95% CI 1.07-1.25; P = 2.17 × 10-4). A 1-unit increase in BMI and triglyceride levels was associated with a 0.08-SD (95% CI 0.06-0.10; P = 2.04 × 10-15) and 0.06-SD (95% CI 0.04-0.08; P = 4.08 × 10-13) increase, respectively, in vaspin in the PURE group. Consistent associations were observed in the ORIGIN cohort. MR results reinforced the association between vaspin and BMI-adjusted T2D risk (OR 1.01 per 1-SD increase in vaspin level; 95% CI 1.00-1.02; P = 2.86 × 10-2) and showed that vaspin was increased by 0.10 SD per 1-SD decrease in genetically determined gluteofemoral adiposity (95% CI 0.02-0.18; P = 2.01 × 10-2). No relationships were found between subcutaneous or visceral adiposity and vaspin. These findings support that higher vaspin levels are related to increased T2D risk and reduced gluteofemoral adiposity, positioning vaspin as a promising clinical predictor for T2D.

Urinary arsenic metabolism, genetic susceptibility, and their interaction on type 2 diabetes

Growing studies investigated the association of arsenic metabolism with type 2 diabetes (T2D), however, the epidemiological evidence is inconsistent. In addition, the interaction of arsenic metabolism-related genetic risk score (GRS)-arsenic on T2D risk was unclear. The present study aimed to evaluate the association of arsenic metabolism efficiency [inorganic arsenic (iAs)%, monomethylarsonic acid (MMA)%, and dimethylarsinic acid (DMA%)] with T2D risk. Moreover, the relationship of GRS and arsenic metabolism efficiency and the interaction of GRS-arsenic on T2D were investigated. Age- and sex-matched new-onset diabetes case-control study derived from the Dongfeng-Tongji cohort was conducted and 996 pairs participants were included in this study. The leave-one-out approach was used to evaluate the association of arsenic metabolism efficiency with T2D risk. The GRS and weight GRS (wGRS) were calculated based on 79 candidate SNPs. We estimated the relationship of GRS with arsenic metabolism efficiency by linear regression model. The interaction of GRS-arsenic on T2D was assessed by adding a multiplicative interaction term (GRS × arsenic) in the logistic regression models. Urinary iAs% was positively associated with T2D risk, and the OR (95% CI) was 1.06 (1.01, 1.12). MMA% and PMI were negatively associated with T2D risk, and the ORs (95% CI) were 0.87 (0.78, 0.97) and 0.64 (0.47, 0.86), respectively. Urinary DMA, As3+, and As5+ were positively associated with T2D risk. Similar relationships were found between arsenic metabolites and levels of FPG and HbA1c. Moreover, arsenic metabolism-related GRS/wGRS was positively associated with MMA% but negatively associated with DMA%. Genetic predisposition to arsenic metabolism modified the association of inorganic arsenic with T2D risk (Pinteraction = 0.033). Taken together, lower arsenic primary metabolism efficiency (higher iAs% and lower MMA%) may increase T2D risk. Genetic predisposition to arsenic metabolism was associated with arsenic metabolism efficiency, and might modify the association of inorganic arsenic with T2D risk.

Chromosomal deletions on 16p11.2 encompassing SH2B1 are associated with accelerated metabolic disease

New approaches are needed to treat people whose obesity and type 2 diabetes (T2D) are driven by specific mechanisms. We investigate a deletion on chromosome 16p11.2 (breakpoint 2-3 [BP2-3]) encompassing SH2B1, a mediator of leptin and insulin signaling. Phenome-wide association scans in the UK (N= 502,399) and Estonian (N= 208,360) biobanks show that deletion carriers have increased body mass index (BMI; p= 1.3×10-10) and increased rates of T2D. Compared with BMI-matched controls, deletion carriers have an earlier onset of T2D, with poorer glycemic control despite higher medication usage. Cystatin C, a biomarker of kidney function, is significantly elevated in deletion carriers, suggesting increased risk of renal impairment. In a Mendelian randomization study, decreased SH2B1 expression increases T2D risk (p= 8.1×10-6). We conclude that people with 16p11.2 BP2-3 deletions have early, complex obesity and T2D and may benefit from therapies that enhance leptin and insulin signaling.

Artificial Sweeteners and Risk of Type 2 Diabetes in the Prospective NutriNet-Santé Cohort.

To study the relationships between artificial sweeteners, accounting for all dietary sources (total and by type of artificial sweetener) and risk of type 2 diabetes (T2D), in a large-scale prospective cohort. The analyses included 105,588 participants from the web-based NutriNet-Santé study (France, 2009-2022; mean age 42.5 ± 14.6 years, 79.2% women). Repeated 24-h dietary records, including brands and commercial names of industrial products, merged with qualitative and quantitative food additive composition data, enabled artificial sweetener intakes to be accurately assessed from all dietary sources. Associations between artificial sweeteners (total, aspartame, acesulfame potassium [K], and sucralose) and T2D were investigated using Cox proportional hazard models adjusted for potential confounders, including weight variation during follow-up. During a median follow-up of 9.1 years (946,650 person-years, 972 incident T2D), compared with nonconsumers, higher consumers of artificial sweeteners (i.e., above the sex-specific medians of 16.4 mg/day in men and 18.5 mg/day in women) had higher risks of developing T2D (hazard ratio [HR] 1.69; 95% CI 1.45-1.97; P-trend <0.001). Positive associations were also observed for individual artificial sweeteners: aspartame (HR 1.63 [95% CI 1.38-1.93], P-trend <0.001), acesulfame-K (HR 1.70 [1.42-2.04], P-trend <0.001), and sucralose (HR 1.34 [1.07-1.69], P-trend = 0.013). Potential for reverse causality cannot be eliminated; however, many sensitivity analyses were computed to limit this and other potential biases. These findings of positive associations between artificial sweetener intakes and increased T2D risk strengthen the evidence that these additives may not be safe sugar alternatives. This study provides important insights in the context of on-going reevaluation of artificial sweeteners by health authorities worldwide.

1466-P: Genome-Wide Association Studies in the GRADE Study Identify Genetic Variation Influencing the Response to Pharmacotherapy for Type 2 Diabetes

Treatment selection for type 2 diabetes (T2D) is largely driven by guidelines based on population-level clinical data and does not incorporate genetics into decision making. To address this gap, we conducted genome-wide association studies in GRADE, a randomized trial comparing the metabolic effects of glargine, glimepiride, liraglutide, or sitagliptin, when added to metformin over a mean follow-up of 5 years. 4,689 participants with T2D from diverse ancestries underwent genome-wide genotyping with the Illumina Infinium GSA 3.0 array, and high-quality imputation was performed with the TOPMed reference panel. We defined cases as meeting the two outcome criteria (primary: HbA1c ≥7%; secondary: HbA1c ≥7.5%) after 1 or 4 years of treatment. Whole-genome logistic regression using an additive model tested for case-control associations for each treatment. Results were filtered to minor allele frequency &amp;gt;0.005 and imputation R2 ≥0.80. We identified four loci associated with glargine response and one with sitagliptin response at standard genome-wide significance (p&amp;lt;5.0×10−8). For glargine, rs116991960 proximal to the RPSAP52 pseudogene region was associated with increased risk of the primary outcome at year 1 (p=2.6×10−8). Interestingly, RPSAP52 interacts with the RNA binding protein IGF2BP2, and genetic variation in IGF2BP2 has been associated with increased T2D risk. Moreover, rs142895019, located in ITPK1, was associated with the secondary outcome for sitagliptin at year 1 (p=9.4×10−9). In a separate Cox proportional hazards survival analysis, C-allele carriers of rs142895019 had an increased risk of treatment failure on sitagliptin (HR 3.6, p=1.0×10−7). In summary, we identified new genetic loci that may be associated with glycemic response in a multi-ancestry clinical trial of common glucose-lowering medications for T2D. These findings require independent validation but have potential utility in guiding therapy selection. Disclosure J.H. Li: None. L. Szczerbinski: None. H. Liu: None. M. Tripputi: None. A. Kretowski: None. S.E. Kahn: Advisory Panel; Anji Pharmaceuticals, Bayer Inc., Boehringer Ingelheim Inc., Eli Lilly and Company, Merck &amp; Co., Inc. Other Relationship; Novo Nordisk. J.M. Lachin: None. N. Younes: None. J.M. Mercader: None. J.C. Florez: Consultant; AstraZeneca. Other Relationship; AstraZeneca, Merck &amp; Co., Inc. Consultant; Novo Nordisk. Funding National Institute of Diabetes and Digestive and Kidney Diseases (U01DK098246, U34DK088043, R01DK123019)

221-LB: Identification of PAM as Novel Monogenic Diabetes Gene

Background/Objectives: Various biological mechanisms involved in type 2 diabetes (T2D) have been unveiled through converging evidence in common variants from Genome wide association studies (GWAS) and rare or low frequency variants (RV/LFV) from Exome wide association studies (EXWAS). We hypothesized that a two-pronged approach interrogating both RV/LFV and common variants could yield identification of new pathways involved in T2D. Methods: Protein-altering RV/LFV burden was tested for T2D association in an EXWAS of 11,731 cases and 149,613 controls in the UKBiobank. Significant encoded proteins were then investigated using 2-sample Mendelian randomization for causal association with T2D and related variables. Protein quantitative trait loci were estimated in the Prospective Urban and Rural Epidemiological study (N=11,020) and tested against GWAS-summary statistics of T2D and related traits from 10 consortia. Results: At the EXWAS significance threshold (P=0.05/19,589=2.55×10-6), we identified loss-of-function RV/LFV in GCK and PAM, which encode the proteins glucokinase and peptidylgycine α-amidating monooxygenase respectively, to be associated with T2D risk. Deleterious mutations in the PAM gene were associated with an 29% increase in T2D risk (OR per RV/LFV=1.29; 95%CI=1.17-1.43; P=7.17×10-7). This association was driven by a low frequency variant, rs78408340-G present in 2.6% of T2D cases and only in 1.8% of controls. MR analyses confirmed that 1 SD decrease in PAM circulating levels was consistently associated with increased T2D risk (OR=1.16; 95%CI=1.14-1.19; P=9.54×10-52) and HbA1c (%) (β=0.0047; 95%CI= 0.00051-0.0090; P=0.028), and decreased post-prandial insulin (mU/L) secretion (β=-0.060; 95% CI=-0.083(-)-0.036; P=8.32×10-7). Conclusion: We identified PAM variants as a novel cause of monogenic diabetes and demonstrated a strong causal effect of circulating PAM levels on T2D risk and post-prandial insulin secretion. This supports further investigation of PAM as a therapeutic T2D target. Disclosure J. Feiner: None. N. Perrot: None. M. Chong: Research Support; Bayer Inc. R. Lali: None. R. Morton: None. P. Mohammadi-Shemirani: None. S. Yusuf: None. H. C. Gerstein: Advisory Panel; Abbott Diagnostics, Eli Lilly and Company, Sanofi. Research Support; Novo Nordisk. Advisory Panel; Novo Nordisk. Research Support; Eli Lilly and Company, Sanofi. Advisory Panel; Kowa Company, Ltd., Hanmi Pharm. Co., Ltd. Other Relationship; Zuellig Pharma Holdings Pte. Ltd., DKSH, AstraZeneca. G. Pare: Research Support; Bayer Inc. Advisory Panel; Bayer Inc., Amgen Inc., Novartis AG. M. Pigeyre: None. Funding Bayer; Canadian Institutes of Health Research

Predicting mechanisms of action at genetic loci associated with discordant effects on type 2 diabetes and abdominal fat accumulation.

Obesity is a major risk factor for cardiovascular disease, stroke, and type 2 diabetes (T2D). Excessive accumulation of fat in the abdomen further increases T2D risk. Abdominal obesity is measured by calculating the ratio of waist-to-hip circumference adjusted for the body-mass index (WHRadjBMI), a trait with a significant genetic inheritance. Genetic loci associated with WHRadjBMI identified in genome-wide association studies are predicted to act through adipose tissues, but many of the exact molecular mechanisms underlying fat distribution and its consequences for T2D risk are poorly understood. Further, mechanisms that uncouple the genetic inheritance of abdominal obesity from T2D risk have not yet been described. Here we utilize multi-omic data to predict mechanisms of action at loci associated with discordant effects on abdominal obesity and T2D risk. We find six genetic signals in five loci associated with protection from T2D but also with increased abdominal obesity. We predict the tissues of action at these discordant loci and the likely effector Genes (eGenes) at three discordant loci, from which we predict significant involvement of adipose biology. We then evaluate the relationship between adipose gene expression of eGenes with adipogenesis, obesity, and diabetic physiological phenotypes. By integrating these analyses with prior literature, we propose models that resolve the discordant associations at two of the five loci. While experimental validation is required to validate predictions, these hypotheses provide potential mechanisms underlying T2D risk stratification within abdominal obesity.

Acrolein Exposure Impaired Glucose Homeostasis and Increased Risk of Type 2 Diabetes: An Urban Adult Population-Based Cohort Study with Repeated Measures

Acrolein is an identified high-priority hazardous air pollutant ubiquitous in daily life and associated with cardiometabolic risk that attracts worldwide attention. However, the etiology role of acrolein exposure in glucose dyshomeostasis and type 2 diabetes (T2D) is unclear. This repeated-measurement prospective cohort study included 3522 urban adults. Urine/blood samples were repeatedly collected for determinations of acrolein metabolites (N-acetyl-S-(3-hydroxypropyl)-l-cysteine, N-acetyl-S-(2-carboxyethyl)-l-cysteine; acrolein exposure biomarkers), glucose homeostasis, and T2D at baseline and a three-year follow-up. We found that each 3-fold increment in acrolein metabolites was cross-sectionally associated with 5.91-6.52% decrement in homeostasis model assessment-insulin sensitivity (HOMA-IS) and 0.07-0.14 mmol/L, 4.02-4.57, 5.91-6.52, 19-20, 18-19, and 23-31% increments in fasting glucose (FPG), fasting insulin (FPI), HOMA-insulin resistance (HOMA-IR), risks of prevalent IR, impaired fasting glucose (IFG), and T2D, respectively; longitudinally, participants with sustained-high acrolein metabolite levels had increased risks of incident IR, IFG, and T2D by 63-80, 87-99, and 120-154%, respectively (P < 0.05). In addition, biomarkers of heme oxygenase-1 activity (exhaled carbon monoxide), lipid peroxidation (8-iso-prostaglandin-F2α), protein carbonylation (protein carbonyls), and oxidative DNA damage (8-hydroxy-deoxyguanosine) mediated 5.00-38.96% of these associations. Our study revealed that acrolein exposure may impair glucose homeostasis and increase T2D risk via mediating mechanisms of heme oxygenase-1 activation, lipid peroxidation, protein carbonylation, and oxidative DNA damage.

You are What You Drink? How Associations Between Profiles of Beverage Consumption and Type 2 Diabetes Risk are Mediated by Biomarker Networks

BackgroundMultiple studies have independently investigated the associations of the consumption of individual beverage types and specific plasma biomarkers with the risk of type 2 diabetes (T2D). However, as individuals do not consume single beverage types exclusively and plasma biomarkers do not act in isolation, it remains unclear how patterns of beverage consumption and plasma biomarker networks associate both with each other and T2D risk. ObjectivesWe aimed to elucidate potential dietary determinants of T2D risk by defining a model that describes habitual beverage consumption profiles in relation to identified networks of circulating plasma biomarkers. MethodsThis study included 1,461 case and 1,568 control participants from case-control studies of T2D nested within the Nurses’ Health Study. Participants completed validated semiquantitative food frequency questionnaires that assessed habitual beverage consumption, and they provided blood samples from which 27 plasma biomarkers of cardiometabolic risk were identified. Common exploratory factor analysis (EFA) identified factors that separately described beverage consumption profiles and biomarker networks. Multivariable-adjusted regression elucidated the relationships between beverage and biomarker factors and T2D risk. ResultsEFA revealed five factors describing unique beverage consumption profiles and seven factors describing biomarker networks. The factor describing alcoholic beverage consumption was associated with a reduced risk of T2D (odds ratio [OR]: 0.50 [0.40, 0.64], P<0.001) mediated, in part, by the factor describing increased concentrations of adiponectin biomarkers (19.9% [12.0, 31.1] P = 0.004). The factor describing low-calorie sweetened beverage (LCSBs) consumption was associated with an increased risk of T2D (OR: 1.33 [1.03, 1.72], P = 0.021), and the factor describing lower concentrations of insulin-like growth factor binding proteins 1 and 2, and soluble leptin receptor, and increased leptin concentrations (P = 0.005). ConclusionsModerate alcohol consumption was associated with reduced T2D risk, mediated in part by increased circulating adiponectin. LCSB consumption was associated with both increased T2D risk and perturbed insulin-like growth factor and leptin signaling.