Risk Of Type 2 Diabetes In Women Research Articles

Prospective risk of Type 2 diabetes in 99892 Nordic women with polycystic ovary syndrome and 446055 controls: national cohort study from Denmark, Finland, and Sweden.

What is the prospective risk of Type 2 diabetes (T2D) in Nordic women with polycystic ovary syndrome (PCOS) compared to controls? A diagnosis of PCOS and BMI ≥30 kg/m2 is a high-risk phenotype for a prospective risk of T2D diagnosis across Nordic countries. The risk of T2D in women with PCOS is increased. The risk of T2D is related to BMI and the magnitude of risk in normal weight women with PCOS has been discussed. However, prospective data regarding risk of T2D in population-based cohorts of women with PCOS are limited. This national register-based study included women with PCOS and age-matched controls. The main study outcome was T2D diagnosis occurring after PCOS diagnosis. T2D was defined according to ICD-10 diagnosis codes and/or filled medicine prescriptions of anti-diabetic medication excluding metformin. The study cohort included women originating from Denmark (PCOS Denmark, N = 27016; controls, N = 133994), Finland (PCOS Finland, N = 20467; controls, N = 58051), and Sweden (PCOS Sweden, N = 52409; controls, N = 254010). The median age at cohort entry was 28 years in PCOS Denmark, Finland, and Sweden with a median follow-up time (interquartile range) in women with PCOS of 8.5 (4.0-14.8), 9.8 (5.1-15.1), and 6.0 (2.0-10.0) years, respectively. Cox regression analyses were adjusted for BMI and length of education. The crude hazard ratio (HR, 95% CI) for T2D diagnosis in women with PCOS was 4.28 (3.98-4.60) in Denmark, 3.40 (3.11-3.74) in Finland, and 5.68 (5.20-6.21) in Sweden. In adjusted regression analyses, BMI ≥30 vs <25 kg/m2 was associated with a 7.6- to 11.3-fold risk of T2D. In a combined meta-analysis (PCOS, N = 99892; controls, N = 446055), the crude HR for T2D in PCOS was 4.64 (3.40-5.87) and, after adjustment for BMI and education level, the HR was 2.92 (2.32-3.51). Inclusion of more severe cases of PCOS in the present study design could have lead to an overestimation of risk estimates in our exposed population. However, some women in the control group would have undiagnosed PCOS, which would lead to an underestimation of T2D risk in women with PCOS. BMI data were not available for all participants. The present study should be repeated in study cohorts with higher background risks of T2D, particularly in populations of other ethnicities. The prospective risk for diagnosis of T2D is increased in women with PCOS, and the risk is aggravated in women with BMI ≥30 kg/m2. Funding in Denmark was from the Region of Southern Denmark, Overlægerådet, Odense University Hospital. Funding in Finland was from Novo Nordisk Foundation, Finnish Research Council and Sigrid Juselius Foundation, the National Regional Fund, Sakari Alhopuro Foundation and Finnish Diabetes Research Foundation. E.E. has received a research grant from Ferring Pharmaceuticals (payment to institution) and serves as medical advisor for Tilly AB, not related to this manuscript. The remaining authors declare no conflict of interest. N/A.

High adherence to the French dietary guidelines decreases type 2 diabetes risk in females through pathways of obesity markers: Evidence from the E3N-EPIC prospective cohort study

Obesity and type 2 diabetes (T2D) have been associated with low adherence to the 2017 French food-based dietary guidelines, as assessed by the Programme National Nutrition Santé - guidelines score 2 (PNNS-GS2). Whether the association between T2D and PNNS-GS2 is direct or mediated by obesity has been little investigated. The study included 71,450 women from the E3N-EPIC cohort, mean age of 52.9 y (SD 6.7). The simplified PNNS-GS2 was derived via food history questionnaire. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of T2D. Causal mediation analyses were used to decompose the total effect of sPNNS-GS2 on T2D into a direct effect and indirect effect mediated by body mass index (BMI) or the waist-hip ratio (WHR). During a mean follow-up of 19 y, 3679 incident T2D cases were identified and validated. There was a linear association between adherence to sPNNS-GS2 and T2D (P-nonlinearity = 0.92). In the fully adjusted model, each 1-SD increase in the sPNNS-GS2 was associated with a lower T2D risk [HR (95% CI), 0.92 (0.89, 0.95)]. The overall associations were mainly explained by sPNNS-GS2-associated excess weight, with BMI and WHR mediating 52% and 58% of the associations, respectively. Higher adherence to French food-based dietary guidelines was associated with a lower risk of T2D in women, and a significant portion of this effect could be attributed to excess weight measured by BMI or WHR. This finding helps better understand the mechanisms underlying the diet-T2D association.

The association of dietary total flavonoids and their subclasses with the risk of type 2 diabetes: a prospective cohort study.

Data from mechanistic studies suggest flavonoids may benefit glucose metabolism, but their associations with type 2 diabetes (T2D) remain unclear. This study examined the prospective associations of dietary intake of total, classes, and individual flavonoids, as well as their source foods, with T2D in the CArdioVascular disease Association Study (CAVAS). A total of 16,666 Korean men and women were enrolled at baseline, and 953 were newly diagnosed with T2D over a median follow-up of 5.96years. Intake of flavonoids was cumulatively averaged using all food frequency questionnaires before the censoring events. A Poisson regression model was used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs). Women with higher total flavonoid, flavonol, isoflavone, and proanthocyanidin intake had a lower risk of T2D (fourth vs. first quartile, IRR 0.62; 95% CI 0.44-0.89; P for linearity and non-linearity < 0.05 for total flavonoids), while in men, flavanones, anthocyanins, and proanthocyanidins, but not total flavonoids, were inversely associated with T2D risk (all P interaction for sex > 0.05). The key source foods contributing to flavonoid intake were also different between men and women, except for apples: tangerines and strawberries in men and green leafy vegetables and soy products in women. A higher intake of total flavonoids, particularly from vegetables, soybeans, and apples, may be associated with lower risk of T2D in women. However, flavonoids from fruits, rather than total flavonoids, may be inversely associated in men. The association between flavonoid intake and the risk of T2D may be contingent upon the dietary sources of flavonoids consumed.

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.

Comparison of bioelectrical body and visceral fat indices and anthropometric measures in relation to type 2 diabetes by sex among Chinese adults, a cross-sectional study.

We aim to compare the efficacies of the bioelectrical indices (percentage of body fat, PBF; visceral fat area, VFA) with the conventional anthropometric measures (body mass index, BMI; waist-hip ratio, WHR) for predicting type 2 diabetes (T2D) risk by sex and to determine the sex-specific optimal adiposity indices to predict the T2D risk. Cross-sectional design. Tianjin First Central Hospital and Tianjin Union Medical Center, Tianjin, China. A total of 9,332 adults (41.35% men) undergoing physical examination. T2D was defined using the WHO's criteria: fasting blood glucose (FBG) ≥7.0 mmol/L and/or previous diagnosis of T2D. Height, weight, waist, hip, PBF, VFA, and fasting plasma glucose were measured. All studied adiposity indices were associated with T2D among both males and females, and the observed associations differed by sex. The standardized aORs of BMI, WHR, PBF and VFA for T2D were 1.60 (95% CI 1.42-1.81), 1.43 (95% CI 1.25-1.64), 1.42 (95% CI 1.23-1.62) and 1.53 (95% CI 1.35-1.75) for females, and 1.47 (95% CI 1.31-1.66), 1.40 (95% CI 1.25-1.58), 1.54 (95% CI 1.36-1.74) and 1.47 (95% CI 1.31-1.65) for males, respectively. The AUCs of VFA, WHR and BMI were 0.743, 0.742 and 0.717 in women, respectively, whereas none of the indices had AUC larger than 0.70 in men. The AUCs were not significantly different between VFA and WHR, while both demonstrate larger AUCs than BMI and PBF in females (all p < 0.05). The optimal cutoff values of VFA, WHR, and BMI for T2D in women were 103.55 cm2, 0.905, and 24.15 kg/m2, respectively. Although BMI, WHR, and PBF and VFA as measured by bioelectrical impedance analysis (BIA) were all positively associated with T2D, their efficacy for predicting the risk of T2D differed by sex. VFA, WHR and BMI could be used as biomarkers to predict T2D risk in women, however none of the study indicators demonstrated favorable efficacy of predicting T2D risk in men.

The association between dietary acrylamide intake and the risk of type 2 diabetes incidence in the Tehran lipid and glucose study

This study aimed at investigating the association of acrylamide consumption with the incidence of type 2 diabetes (T2D) in adults. The 6022 subjects of the Tehran lipid and glucose study participants were selected. The acrylamide content of food items were summed and computed cumulatively across follow up surveys. Multivariable Cox proportional hazard regression analyses were performed to estimate the hazards ratio (HR) and 95% confidence interval (CI) of incident T2D. This study was done on men and women, respectively aged 41.5 ± 14.1 and 39.2 ± 13.0 years. The mean ± SD of dietary acrylamide intake was 57.0 ± 46.8 µg/day. Acrylamide intake was not associated with the incidence of T2D after adjusting for confounding variables. In women, a higher acrylamide intake was positively associated with T2D [HR (CI) for Q4: 1.13 (1.01–1.27), P trend: 0.03] after adjusting for confounding factors. Our results demonstrated that dietary intake of acrylamide was associated with an increased risk of T2D in women.

Abstract P346: Adherence to the French Dietary Guidelines and Type 2 Diabetes Risk: The E3n-Epic Prospective Cohort Study

Background: Recently, a dietary index reflecting adherence to the 2017 French food-based dietary guidelines, the Programme National Nutrition Santé - guidelines score 2 (PNNS-GS2), has been developed, but evidence on its level of adherence and incident type 2 diabetes (T2D) risk is limited. Objective: We aimed to investigate the association between adherence to the simplified PNNS-GS2 (sPNNS-GS2) and the risk of incident T2D in a French cohort of women. Methods: Between 1993 and 2014, 71,450 women aged over 18 years were examined, and thereafter followed up for the occurrence of T2D within the E3N-EPIC prospective cohort. Dietary data were collected at baseline via a food frequency questionnaire, and the sPNNS-GS2 was derived for each participant. Multivariable Cox regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of T2D for continuous and quintile groups of the sPNNS-GS2. Effect modification by body mass index (BMI) and mediation by BMI and waist-hip ratio (WHR) were explored. Results: The mean age was 52.9 years (SD 6.7). During a mean follow-up of 19 years, 3679 incident T2D cases were identified and validated. There was a linear association between adherence to sPNNS-GS2 and T2D risk (P non-linear = 0.85). In the fully adjusted model, each 1-SD increase in the sPNNS-GS2 was associated with a 8% decrease risk of T2D [HR (95% CI), 0.92 (0.89, 0.95)]. Compared to those with the lowest adherence (first quintile), the third [HR (95% CI), 0.91 (0.82, 1.00)] up to the fifth quintile group [HR (95% CI), 0.79 (0.71, 0.88)] had a lower T2D risk. There was a sPNNS-GS2 x BMI interaction on T2D risk (P interaction &lt; 0.01) but not with WHR. The overall association was partly mediated by BMI (18%) and WHR (59%). Conclusion: Higher adherence to the 2017 French food-based dietary guidelines was associated with a lower risk of T2D in women. Furthermore, our mediation analysis suggests that the lower risk of T2D in women associated with adherence to the sPNNS-GS2 is partly mediated by obesity measured by BMI or WHR.

Lifestyle intervention for the prevention of type 2 diabetes in women with prior gestational diabetes: A systematic review and meta-analysis.

To determine whether current evidence supports lifestyle intervention for type 2 diabetes (T2D) prevention in women with previous gestational diabetes (GD). We systematically searched MEDLINE/PubMed, Web of Science, EMBASE, The Cochrane Library, International Pharmaceutical Abstracts, Global Health, Sinomed and Clinicaltrials.gov for randomized controlled trials (published from 1 January 1950 to 14 December 2022) comparing lifestyle intervention with standard care in women with previous GD. Our primary outcome was incident T2D, with pooled estimates calculated by a fixed-effects model. Of 1652 studies identified, 13 were eligible and were included in our analysis (N=3745 women). Compared with standard care, lifestyle intervention yielded a reduction of 24% in the incidence of T2D (relative risk 0.76 [95% CI 0.63-0.93]). Meta-regression analyses revealed no impact of the duration of lifestyle intervention (P=.81) or baseline body mass index (P=.90) on the observed reduction in incident T2D. Importantly, this published literature shows evidence of publication bias on funnel plot and Egger test (P=.048). Current published evidence suggests that lifestyle intervention can reduce the risk of T2D in women with prior GD. However, this finding should be interpreted with caution in the presence of documented publication bias.

Adiposity, related biomarkers, and type 2 diabetes after gestational diabetes: The Diabetes Prevention Program.

This study investigated associations of adiposity and adiposity-related biomarkers with incident type 2 diabetes (T2D) among parous women. Among women in the Diabetes Prevention Program (DPP) who reported a previous live birth, circulating biomarkers (leptin, adiponectin, sex hormone-binding globulin, and alanine aminotransferase; n = 1,711) were measured at enrollment (average: 12 years post partum). Visceral (VAT) and subcutaneous adipose tissue areas at the L2-L3 region and the L3-L4 region were quantified by computed tomography (n = 477). Overall and stratified (by history of gestational diabetes mellitus [GDM]) adjusted Cox proportional hazards models were fit. Alanine aminotransferase, L2-L3 VAT, and L3-L4 VAT were positively associated (hazard ratio [HR] for 1-SD increases: 1.073, p = 0.024; 1.251, p = 0.009; 1.272, p = 0.004, respectively), and adiponectin concentration was inversely associated with T2D (HR 0.762, p < 0.001). Whereas leptin concentration was not associated with T2D overall, in GDM-stratified models, a 1-SD higher leptin was positively associated with risk of T2D in women without GDM (HR: 1.126, p = 0.016) and inversely in women with a history of GDM (HR: 0.776, p = 0.013, interaction p = 0.002). Among parous women, alanine aminotransferase and VAT are positively associated with incident T2D, whereas adiponectin is inversely associated. Leptin is associated with higher risk of T2D in women with a history of GDM but a lower risk in women without a history of GDM.

Association of the odd-chain fatty acid content in lipid groups with type 2 diabetes risk: A targeted analysis of lipidomics data in the EPIC-Potsdam cohort

Plasma odd-chain saturated fatty acids (OCFA) are inversely associated with type 2 diabetes (T2D) risk and may serve as biomarkers for dairy fat intake. Their distribution across different lipid classes and consequences for diabetes risk remain unknown. To investigate the prospective associations of OCFA-containing lipid species with T2D risk and their dietary determinants. Within the European Prospective Investigation into Cancer and Nutrition-Potsdam study (n=27,548), we applied a nested case-cohort design (subcohort: n=1,248; T2D cases: n=820; median follow-up 6.5 years). OCFA-containing lipids included triacylglycerols, free fatty acids (FFA), cholesteryl esters (CE), phosphatidylcholines, phosphatidylethanolamines, lysophosphatidylcholines, lysophosphatidylethanolamines, monoacylglycerols, and diacylglycerols. We estimated lipid class-specific associations between OCFA-containing lipids and T2D in sex-stratified Cox proportional-hazards models. We investigated correlations between lipids and dietary intakes derived from food-frequency questionnaires. We observed heterogeneous integration of OCFA in different lipid classes: triacylglycerols, FFA, CE, and phosphatidylcholines contributed most to the total OCFA-plasma abundance. The relative concentration of OCFA was particularly high in monoacylglycerols, and the contribution of C15:0 versus C17:0 to the total OCFA-abundance differed across lipid classes. In women, several OCFA-containing phospholipids were inversely associated with T2D risk [phosphatidylcholine(C15:0), HR Q5 vs Q1: 0.56, 95% CI 0.32-0.97; phosphatidylcholine(C17:0), HR per SD: 0.59, 95% CI 0.48-0.71; lysophosphatidylcholine(C17:0), HR Q5 vs Q1: 0.42, 95% CI 0.23-0.76]. In men, we did not detect statistically significant inverse associations in phospholipids, and lysophosphatidylcholine(C15:0) was associated with higher T2D risk (HR Q5 vs. Q1: 1.96, 95% CI 1.06-3.63). Besides, CE(C17:0), monoacylglycerols(C15:0), and diacylglycerols(C15:0) were inversely associated with T2D risk; FFA(C17:0) was positively associated with T2D risk in women. Consumption of fat-rich dairy and fiber-rich foods were positively and red meat inversely correlated to OCFA-containing lipid plasma levels. OCFA-containing lipids are linked to T2D risk in a lipid class and sex-specific manner, and they are correlated with several foods.

Fruit and vegetable intake is inversely associated with type 2 diabetes in Chinese women: results from the China Health and Nutrition Survey

This study aimed to evaluate the associations between fruit and vegetable (FV) intake and the risk of prediabetes or type 2 diabetes (T2D). It is a cross-sectional study that involved 6802 participants aged 18–65 years. Dietary intake and other variables were assessed by questionnaires. The prevalence of prediabetes and T2D was ascertained by self-report and analyses of fasting blood samples. In the multiple logistic regression models, FV intake was negatively associated the risk of T2D in women (OR = 0.45, 95% CI: 0.28, 0.71), whereas no such association was observed in men (OR = 0.98, 95% CI: 0.65, 1.47). Furthermore, FV consumption was inversely associated with prediabetes risk in men and women. Results suggested that higher intake of FV was associated with a decreased risk of T2D or prediabetes in Chinese women and a reduced risk of prediabetes in men only.

Abstract P132: Anti-Müllerian Hormone Levels and Risk of Type 2 Diabetes in Women

Introduction: Given its role in ovarian follicle development, circulating anti-Müllerian hormone (AMH) is correlated with timing of menopause. Accordingly, women with higher AMH levels become menopausal at a higher age. Previous research suggests that a higher age at menopause is associated with a decreased risk of type 2 diabetes (T2D). In contrast, AMH levels are increased in women with polycystic ovary syndrome (PCOS), who have a higher risk of insulin resistance and T2D than women without PCOS. However, it is not clear yet whether AMH actually plays a role in the development of T2D. We aimed to investigate whether plasma AMH levels and age-related AMH trajectories are associated with risk of T2D in women. Hypothesis: Higher age-specific plasma AMH levels are associated with a decreased risk of T2D. Methods: We analyzed longitudinal data from 3104 female participants, aged 20-60 years at recruitment, in the population-based Doetinchem Cohort Study. In total, we analyzed 12460 plasma AMH measurements. We calculated age-specific AMH tertiles, to account for the strong AMH-age correlation. Cox Proportional hazards models adjusted for known risk factors for diabetes were used to assess the relation between age-specific AMH tertiles and T2D. We applied linear mixed models to compare age-related AMH trajectories between T2D cases and non-cases. Results: After a median follow-up of 20 years, 163 incident T2D cases were identified. Higher age-specific AMH levels were associated with a lower risk of T2D (hazard ratio (HR) T2vsT1 = 0.77, 95%CI: 0.53-1.11; HR T3vsT1 =0.62, 95%CI: 0.40-0.94; p for trend = 0.02). These findings were supported by predicted AMH trajectories, which suggested that plasma AMH levels were lower at younger ages and declined at a slower rate in women who were diagnosed with T2D compared to women who were not. However, differences in trajectories between T2D cases and non-cases were not statistically significant. Conclusions: We observed that women with higher age-specific AMH levels were at a lower risk of T2D. In addition, our longitudinal analyses may suggest that AMH is lower in women who develop T2D compared to women who do not. These findings are in line with previous studies that observed that a higher age at menopause was associated with a decreased risk of T2D.

Sex-Specific Association of Circulating Ferritin Level and Risk of Type 2 Diabetes: A Dose-Response Meta-Analysis of Prospective Studies.

Although the role of iron in the development of type 2 diabetes (T2D) has long been a concern, prospective studies directly linking body iron stores to T2D risk in a sex-dependent context have been inconsistent. A systematic meta-analysis was conducted to explore the sex-specific association of circulating ferritin with T2D risk. We searched PubMed, Web of Science, and EMBASE databases to identify available prospective studies through 1 August 2018. Fifteen prospective studies comprising 77,352 participants and 18,404 patients with T2D, aged 20 to 80 years, and with ∼3 to 17 years of follow-up were identified. For each 100-μg/L increment in ferritin levels of overall participants, T2D risk increased by 22% (RR, 1.22; 95% CI, 1.14 to 1.31). Of note, major heterogeneities by sex were identified, with increased ferritin level having an apparently greater effect on T2D risk in women (RR, 1.53; 95% CI, 1.29 to 1.82) than in men (RR, 1.21; 95% CI, 1.15 to 1.27) after exclusion of a study with high heterogeneity (41,512 men and 6974 women for sex-specific analyses; P = 0.020 for sex difference). Further nonlinear analysis between circulating ferritin and T2D risk also showed sex-dimorphic association in that the T2D risk of women was twice as strong in magnitude as that of men at the same ferritin level. Greater circulating ferritin levels were independently associated with increased T2D risk, which appeared stronger among women than men. Our findings provide prospective evidence for further testing of the utility of ferritin levels in predicting T2D risk in a sex-specific manner.

Abstract MP54: Circulating Prolactin Concentrations and Risk of Type 2 Diabetes in US Women

Background: Prolactin, a multifunctional hormone, is involved in regulating insulin sensitivity and glucose homeostasis in experimental and cross-sectional human studies. However, whether circulating levels of prolactin are associated with risk of type 2 diabetes (T2D) remains unclear. Methods: We analyzed the prospective relationship between circulating prolactin levels and T2D risk in in the Nurses’ Health Study (NHS) and Nurses’ Health Study II (NHSII) with up to 22 years of follow-up. Total plasma prolactin was measured using immunoassay in 8,637 women free of T2D and cardiovascular disease at baseline blood collection (NHSI: 1989-1990; NHSII: 1996-1999) and a subset of 1,017 NHS women who provided a second blood sample in 2000-2002. In addition, baseline bioactive prolactin levels were measured in a subset of 2,658 women using the Nb2 lymphoma cell bioassay. We calculated hazard ratios (HRs) using Cox regressions. Results: A total of 701 incident T2D cases were documented during 159,517 person-years of follow-up. Circulating prolactin levels were inversely associated with T2D risk; the multivariable HR comparing the highest with the lowest quartile of prolactin levels was 0.71 (95% confidence interval, 0.54-0.93; P trend =0.02). The associations were similar by menopausal status and risk factors ( P &gt;0.70 for interaction). Additional adjustment for sex hormones, growth factors, adipokine, and inflammatory markers did not alter the results. The association of bioactive prolactin with T2D risk was suggestively stronger than that of total prolactin (comparable HR=0.56 vs. 0.82 among the 2,658 women). The inverse association of total plasma prolactin with incident T2D waned linearly with time, with a significant association observed during the first 9 years after blood draw. Conclusion: High circulating prolactin level was independently associated with lower risk of T2D in women. Our findings are consistent with experimental evidence, supporting a possible protective role for prolactin in the pathogenesis of T2D.

Association of Multiple Biomarkers of Iron Metabolism and Type 2 Diabetes: The EPIC-InterAct Study.

Observational studies show an association between ferritin and type 2 diabetes (T2D), suggesting a role of high iron stores in T2D development. However, ferritin is influenced by factors other than iron stores, which is less the case for other biomarkers of iron metabolism. We investigated associations of ferritin, transferrin saturation (TSAT), serum iron, and transferrin with T2D incidence to clarify the role of iron in the pathogenesis of T2D. The European Prospective Investigation into Cancer and Nutrition-InterAct study includes 12,403 incident T2D cases and a representative subcohort of 16,154 individuals from a European cohort with 3.99 million person-years of follow-up. We studied the prospective association of ferritin, TSAT, serum iron, and transferrin with incident T2D in 11,052 cases and a random subcohort of 15,182 individuals and assessed whether these associations differed by subgroups of the population. Higher levels of ferritin and transferrin were associated with a higher risk of T2D (hazard ratio [HR] [95% CI] in men and women, respectively: 1.07 [1.01-1.12] and 1.12 [1.05-1.19] per 100 μg/L higher ferritin level; 1.11 [1.00-1.24] and 1.22 [1.12-1.33] per 0.5 g/L higher transferrin level) after adjustment for age, center, BMI, physical activity, smoking status, education, hs-CRP, alanine aminotransferase, and γ-glutamyl transferase. Elevated TSAT (≥45% vs. <45%) was associated with a lower risk of T2D in women (0.68 [0.54-0.86]) but was not statistically significantly associated in men (0.90 [0.75-1.08]). Serum iron was not associated with T2D. The association of ferritin with T2D was stronger among leaner individuals (Pinteraction < 0.01). The pattern of association of TSAT and transferrin with T2D suggests that the underlying relationship between iron stores and T2D is more complex than the simple link suggested by the association of ferritin with T2D.

Carbohydrate quality and quantity and risk of type 2 diabetes in US women

Carbohydrate quality may be an important determinant of type 2 diabetes (T2D); however, relations between various carbohydrate quality metrics and T2D risk have not been systematically investigated. The purpose of this study was to prospectively examine the association between carbohydrates, starch, fibers, and different combinations of these nutrients and risk of T2D in women. We prospectively followed 70,025 women free of cardiovascular disease, cancer, and diabetes at baseline from the Nurses' Health Study (1984-2008). Diet information was collected with the use of a validated questionnaire every 4 y. Cox regression was used to evaluate associations with incident T2D. During 1,484,213 person-years of follow-up, we ascertained 6934 incident T2D cases. In multivariable analyses, when extreme quintiles were compared, higher carbohydrate intake was not associated with T2D (RR = 0.98; 95% CI: 0.89, 1.08; P-trend = 0.84), whereas starch was associated with a higher risk (RR = 1.23; 95% CI: 1.12, 1.35; P-trend <0.0001). Total fiber (RR = 0.80; 95% CI: 0.72, 0.89; P-trend < 0.0001), cereal fiber (RR = 0.71, 95% CI: 0.65, 0.78; P-trend < 0.0001), and fruit fiber (RR = 0.79; 95% CI: 0.72, 0.85; P-trend < 0.0001) were associated with a lower T2D risk. The ratio of carbohydrate to total fiber intake was marginally associated with a higher risk of T2D (RR = 1.09; 95% CI: 1.00, 1.20; P-trend = 0.04). On the other hand, we found positive associations between the ratios of carbohydrate to cereal fiber (RR = 1.28; 95% CI: 1.17, 1.39; P-trend < 0.0001), starch to total fiber (RR = 1.12; 95% CI: 1.02, 1.23; P-trend = 0.03), and starch to cereal fiber (RR = 1.39; 95% CI: 1.27, 1.53; P-trend < 0.0001) and T2D. Diets with high starch, low fiber, and a high starch-to-cereal fiber ratio were associated with a higher risk of T2D. The starch-to-cereal fiber ratio of the diet may be a novel metric for assessing carbohydrate quality in relation to T2D.

Adherence to a Healthy Nordic Food Index Is Associated with a Lower Risk of Type-2 Diabetes--The Danish Diet, Cancer and Health Cohort Study.

Background: Type-2 diabetes (T2D) prevalence is rapidly increasing worldwide. Lifestyle factors, in particular obesity, diet, and physical activity play a significant role in the etiology of the disease. Of dietary patterns, particularly the Mediterranean diet has been studied, and generally a protective association has been identified. However, other regional diets are less explored. Objective: The aim of the present study was to investigate the association between adherence to a healthy Nordic food index and the risk of T2D. The index consists of six food items: fish, cabbage, rye bread, oatmeal, apples and pears, and root vegetables. Methods: Data was obtained from a prospective cohort study of 57,053 Danish men and women aged 50–64 years, at baseline, of whom 7366 developed T2D (median follow-up: 15.3 years). The Cox proportional hazards model was used to assess the association between the healthy Nordic food index and risk of T2D, adjusted for potential confounders. Results: Greater adherence to the healthy Nordic food index was significantly associated with lower risk of T2D after adjusting for potential confounders. An index score of 5−6 points (high adherence) was associated with a statistically significantly 25% lower T2D risk in women (HR: 0.75, 95%CI: 0.61–0.92) and 38% in men (HR: 0.62; 95%CI: 0.53–0.71) compared to those with an index score of 0 points (poor adherence). Conclusion: Adherence to a healthy Nordic food index was found to be inversely associated with risk of T2D, suggesting that regional diets other than the Mediterranean may also be recommended for prevention of T2D.

Olive oil consumption and risk of type 2 diabetes in US women

Olive oil has been shown to improve various cardiometabolic risk factors. However, to our knowledge, the association between olive oil intake and type 2 diabetes (T2D) has never been evaluated in the US population. We aimed to examine the association between olive oil intake and incident T2D. We followed 59,930 women aged 37-65 y from the Nurses' Health Study (NHS) and 85,157 women aged 26-45 y from the NHS II who were free of diabetes, cardiovascular disease, and cancer at baseline. Diet was assessed by validated food-frequency questionnaires, and data were updated every 4 y. Incident cases of T2D were identified through self-report and confirmed by supplementary questionnaires. After 22 y of follow-up, we documented 5738 and 3914 incident cases of T2D in the NHS and NHS II, respectively. With the use of Cox regression models with repeated measurements of diet and multivariate adjustment for major lifestyle and dietary factors, the pooled HR (95% CI) of T2D in those who consumed >1 tablespoon (>8 g) of total olive oil per day compared with those who never consumed olive oil was 0.90 (0.82, 0.99). The corresponding HRs (95% CIs) were 0.95 (0.87, 1.04) for salad dressing olive oil and 0.85 (0.74, 0.98) for olive oil added to food or bread. We estimated that substituting olive oil (8 g/d) for stick margarine, butter, or mayonnaise was associated with 5%, 8%, and 15% lower risk of T2D, respectively, in the pooled analysis of both cohorts. Our results suggest that higher olive oil intake is associated with modestly lower risk of T2D in women and that hypothetically substituting other types of fats and salad dressings (stick margarine, butter, and mayonnaise) with olive oil is inversely associated with T2D.

Phobic anxiety symptom scores and incidence of type 2 diabetes in US men and women.

Emotional stress may be a risk factor for type 2 diabetes (T2D), but the relation between phobic anxiety symptoms and risk of T2D is uncertain. To evaluate prospectively the association between phobic anxiety symptoms and incident T2D in three cohorts of US men and women. We followed 30,791 men in the Health Professional's Follow-Up Study (HPFS) (1988-2008), 68,904 women in the Nurses' Health Study (NHS) (1988-2008), and 79,960 women in the Nurses' Health Study II (NHS II) (1993-2011). Phobic anxiety symptom scores, as measured by the Crown-Crisp index (CCI), calculated from 8 questions, were administered at baseline and updated in 2004 for NHS, in 2005 for NHS II, and in 2000 for HPFS. Incident T2D was confirmed by a validated supplementary questionnaire. We used Cox proportional hazards analysis to evaluate associations with incident T2D. During 3,099,651 person-years of follow-up, we documented 12,831 incident T2D cases. In multivariate Cox proportional-hazards models with adjustment for major lifestyle and dietary risk factors, the hazard ratios (HRs) of T2D across categories of increasing levels of CCI (scores=2 to <3, 3 to <4, 4 to <6, ⩾6), compared with a score of <2, were increased significantly by 6%, 10%, 10% and 13% (Ptrend=0.001) for NHS; and by 19%, 11%, 21%, and 29% (Ptrend<0.0001) for NHS II. Each score increment in CCI was associated with 2% higher risk of T2D in NHS (HRs, 1.02, 95% confidence intervals: 1.01-1.03) and 4% higher risk of T2D in NHS II (HRs, 1.04, 95% confidence intervals: 1.02-1.05). Further adjustment for depression did not change the results. In HPFS, the association between CCI and T2D was not significant after adjusting for lifestyle variables. Our results suggest that higher phobic anxiety symptoms are associated with an increased risk of T2D in women.

Work Stress, Sense of Coherence, and Risk of Type 2 Diabetes in a Prospective Study of Middle-Aged Swedish Men and Women

OBJECTIVETo investigate the prospective influence of work stress on type 2 diabetes (T2D).RESEARCH DESIGN AND METHODSThis population-based cohort included 3,205 women and 2,227 men, aged 35–56 years, with baseline normal glucose tolerance measured with oral glucose tolerance test. At follow-up 8–10 years later, T2D was diagnosed in 60 women and 111 men. Work stress factors evaluated by questionnaire (i.e., demands, decision latitude, job strain, shift work, overtime work, and also sense of coherence) were studied in association with T2D. Odds ratios (ORs) and 95% CIs adjusted for age, education, BMI, physical activity, smoking, family history of diabetes, and psychological distress were calculated.RESULTSIn women, low decision latitude was associated with T2D on its own (OR 2.4 [95% CI 1.1–5.2]) and combined with high demands: job strain (OR 4.2 [2.0–8.7]), adjusted for all available potential confounders. Also, shift work increased the risk of T2D in women (OR 2.2 [1.0–4.7]) when adjusted for age, education, and psychological distress, although this risk was diluted after multifactor adjustment (OR 1.9 [0.8–4.4]). In men, high work demands and high strain decreased the risk of T2D (OR 0.5 [0.3–0.9]) for both measures, as did an active job (high demands and high decision latitude, OR 0.4 [0.2–0.9]).CONCLUSIONSWork stress and shift work may contribute to the development of T2D in women. In men, the risk was decreased by high work demands, high strain, and an active job.