Search

OBJECTIVE We evaluated prospectively the association between incident early-onset (diagnosed before 40 years of age) and later-onset type 2 diabetes and early-onset (diagnosed before 50 years of age) and later-onset cancer risk. RESEARCH DESIGN AND METHODS We prospectively followed 228,073 eligible participants in the Nurses’ Health Studies for up to 38 years. Hazard ratios (HRs) and 95% CI were estimated using Cox models. RESULTS We documented 18,290 type 2 diabetes, 6,520 early-onset cancer, and 36,907 later-onset cancer cases during follow-up. In fully adjusted analyses, early-onset type 2 diabetes was associated with increased risk of early-onset total cancer (HR [95% CI] 1.47 [1.06–2.04]), diabetes-related cancer (2.11 [1.38–3.23]), and obesity-related cancer (1.75 [1.08–2.82]), and the risk elevations were restricted to those with a BMI at 18 years of age of ≥21 kg/m2 (total cancer: 1.75 [1.20–2.56]; diabetes-related cancer: 2.43 [1.50–3.94]; and obesity-related cancer: 1.84 [1.05–3.22]). Early-onset type 2 diabetes was associated with higher risk of later-onset diabetes-related and obesity-related cancer specifically among individuals with higher BMI at 18 years of age. Later-onset type 2 diabetes was associated with a higher risk of later-onset total cancer (1.15 [1.11–1.20]), diabetes-related cancer (1.17 [1.12–1.22]), and obesity-related cancer (1.18 [1.13–1.24]). In analyses based on refined timing, the HRs attenuated substantially with aging. CONCLUSIONS Incident early-onset type 2 diabetes was associated with increased risk of early-onset total cancer and diabetes- and obesity-related cancer, especially in those with higher BMI at 18 years of age. The impact of early-onset type 2 diabetes on cancer risk may be inherently stronger than that of later-onset type 2 diabetes.

OBJECTIVE We examined the relationship between ultra-processed food (UPF) intake and type 2 diabetes (T2D) risk among 3 large U.S. cohorts, conducted a meta-analysis of prospective cohort studies, and assessed meta-evidence quality. RESEARCH DESIGN AND METHODS We included 71,871 women from the Nurses’ Health Study, 87,918 women from the Nurses’ Health Study II, and 38,847 men from the Health Professional Follow-Up Study. Diet was assessed using food frequency questionnaires and UPF was categorized per the NOVA classification. Associations of total and subgroups of UPF with T2D were assessed using Cox proportional hazards models. We subsequently conducted a meta-analysis of prospective cohort studies on total UPF and T2D risk, and assessed meta-evidence quality using the NutriGrade scoring system. RESULTS Among the U.S. cohorts (5,187,678 person-years; n = 19,503 T2D cases), the hazard ratio for T2D comparing extreme quintiles of total UPF intake (percentage of grams per day) was 1.46 (95% CI 1.39–1.54). Among subgroups, refined breads; sauces, spreads, and condiments; artificially and sugar-sweetened beverages; animal-based products; and ready-to-eat mixed dishes were associated with higher T2D risk. Cereals; dark and whole-grain breads; packaged sweet and savory snacks; fruit-based products; and yogurt and dairy-based desserts were associated with lower T2D risk. In the meta-analysis (n = 415,554 participants; n = 21,932 T2D cases), each 10% increment in total UPF was associated with a 12% (95% CI 10%–13%) higher risk. Per NutriGrade, high-quality evidence supports this relationship. CONCLUSION High-quality meta-evidence shows that total UPF consumption is associated with higher T2D risk. However, some UPF subgroups were associated with lower risk in the U.S. cohorts.

OBJECTIVE The present study aims to prospectively examine the association between post-diagnosis low carbohydrate diet (LCD) patterns and mortality among individuals with type 2 diabetes (T2D). RSEARCH DESIGN AND METHODS Among participants with incident diabetes identified in the Nurses’ Health Study and Health Professionals Follow-Up Study, an overall total low carbohydrate diet score (TLCDS) was calculated based on the percentage of energy as total carbohydrates. In addition, vegetable (VLCDS), animal (ALCDS), healthy (HLCDS), and unhealthy LCDS (ULCDS) were further derived that emphasized different sources and quality of macronutrients. Multivariable-adjusted Cox model were used to assess the association between the LCDS and mortality. RESULTS Among 10,101 incident T2D cases contributing 139,407 person-years during follow-up, we documented 4,595 deaths of which 1,389 cases were attributed to cardiovascular disease (CVD) and 881 to cancer. The pooled multivariable-adjusted hazard ratios (HRs, 95% CIs) of total mortality per 10 points increment of post-diagnosis LCDS were 0.87 (0.82,0.92) for TLCDS, 0.76 (0.71,0.82) for VLCDS, and 0.78 (0.73,0.84) for HLCDS. Both VLCDS and HLCDS were also associated with significantly lower CVD and cancer mortality. Each 10 points increase of TLCDS, VLCDS, and HLCDS from pre-diagnosis to post-diagnosis period was associated with 12% (7%, 17%), 25% (19%, 30%), and 25% (19%, 30%) lower total mortality, respectively. No significant associations were observed for ALCDS and ULCDS. CONCLUSIONS Among people with T2D, greater adherence to LCD patterns that emphasize high quality sources of macronutrients was significantly associated with lower total, cardiovascular, and cancer mortality.

BACKGROUND Due to the rapidly increasing availability of metabolomics data in prospective studies, an update of the meta evidence on metabolomics and type 2 diabetes risk is warranted. PURPOSE To conduct an updated systematic review and meta-analysis of plasma, serum, and urine metabolite markers and incident type 2 diabetes. DATA SOURCES We searched PubMed and Embase until 6 March 2021. STUDY SELECTION We selected prospective observational studies where investigators used high-throughput techniques to investigate the relationship between plasma, serum, or urine metabolites and incident type 2 diabetes. DATA EXTRACTION Baseline metabolites per-SD risk estimates and 95% CIs for incident type 2 diabetes were extracted from all eligible studies. DATA SYNTHESIS A total of 61 reports with 71,196 participants and 11,771 type 2 diabetes cases/events were included in the updated review. Meta-analysis was performed for 412 metabolites, of which 123 were statistically significantly associated (false discovery rate–corrected P < 0.05) with type 2 diabetes risk. Higher plasma and serum levels of certain amino acids (branched-chain, aromatic, alanine, glutamate, lysine, and methionine), carbohydrates and energy-related metabolites (mannose, trehalose, and pyruvate), acylcarnitines (C4-DC, C4-OH, C5, C5-OH, and C8:1), the majority of glycerolipids (di- and triacylglycerols), (lyso)phosphatidylethanolamines, and ceramides included in meta-analysis were associated with higher risk of type 2 diabetes (hazard ratio 1.07–2.58). Higher levels of glycine, glutamine, betaine, indolepropionate, and (lyso)phosphatidylcholines were associated with lower type 2 diabetes risk (hazard ratio 0.69–0.90). LIMITATIONS Substantial heterogeneity (I2 > 50%, τ2 > 0.1) was observed for some of the metabolites. CONCLUSIONS Several plasma and serum metabolites, including amino acids, lipids, and carbohydrates, are associated with type 2 diabetes risk.

Salivary amylase, encoded by the AMY1 gene, is responsible for the digestion of carbohydrates. We investigated associations of AMY1 genetic variations with general and central adiposity changes considering dietary carbohydrate intake among 32,054 adults from four prospective cohort studies. A genetic risk score (GRS) was calculated based on nine AMY1 single-nucleotide polymorphisms, with higher AMY1-GRS indicating higher activity of salivary amylase. We meta-analyzed interactions between AMY1-GRS and dietary intake for changes in general and central adiposity over 5.5–10 years. We found that carbohydrate food intake significantly altered associations of AMY1-GRS with changes in BMI (Pinteraction = 0.001) and waist circumference (Pinteraction < 0.001). Results were consistent and significant in female cohorts rather than in male cohorts. Among women, higher AMY1-GRS was associated with more increases in adiposity if dietary carbohydrate food intake was high, while higher AMY1-GRS was associated with less gains in adiposity when the dietary intake was low. Also, in a 2-year randomized dietary intervention trial, associations of AMY1-GRS with changes in weight (Pinteraction = 0.023) and waist circumference (Pinteraction = 0.037) were significantly modified by carbohydrate intake. Our results suggest the importance of precision nutrition strategies considering participants’ genetic adaptation to carbohydrate-rich diets in regulating general and central adiposity.

OBJECTIVE To identify sleep duration trajectories from early to middle adulthood and their associations with incident type 2 diabetes. RESEARCH DESIGN AND METHODS Using a group-based modeling approach, we identified sleep duration trajectories based on sleep duration in ages 20–25, 26–35, 36–45, and 46+ years, which were retrospectively assessed in 2009 among 60,068 women from the Nurses’ Health Study II (median age 54.9 years) who were free of diabetes, cardiovascular disease, and cancer. We investigated the prospective associations between sleep duration trajectories and diabetes risk (2009–2017) using multivariable Cox proportional hazards models. RESULTS We documented 1,797 incident diabetes cases over a median follow-up of 7.8 years (442,437 person-years). Six sleep duration trajectories were identified: persistent 5-, 6-, 7-, or 8-h sleep duration and increased or decreased sleep duration. After multivariable adjustment for diabetes risk factors, compared with the persistent 7-h sleep duration group, the hazard ratio was 1.43 (95% CI 1.10, 1.84) for the 5-h group, 1.17 (1.04, 1.33) for the 6-h group, 0.96 (0.84, 1.10) for the 8-h group, 1.33 (1.09, 1.61) for the increased sleep duration group, and 1.32 (1.10, 1.59) for the decreased sleep duration group. Additional adjustment for time-updated comorbidities and BMI attenuated these associations, although a significantly higher risk remained in the decreased sleep duration group (1.24 [1.03, 1.50]). CONCLUSIONS Persistent short sleep duration or changes in sleep duration from early to middle adulthood were associated with higher risk of type 2 diabetes in later life. These associations were weaker after obesity and metabolic comorbidities were accounted for.

OBJECTIVE We examined lifestyle factors with midlife weight change according to history of gestational diabetes mellitus (GDM) in a large longitudinal female cohort. RESEARCH DESIGN AND METHODS In the Nurses’ Health Study II, we categorized changes in lifestyle within 4-year periods and estimated their associations with concurrent changes in body weight (kilograms) among parous women after age 40 years by GDM history status (N = 54,062; 5.3% with a history of GDM) for the following: diet quality (Alternate Healthy Eating Index [AHEI]), leisure-time physical activity (PA), alcohol consumption, and smoking status. RESULTS Over a median follow-up of 13 years, average 4-year weight gain was 1.10 and 1.33 kg for women with and without prior GDM, respectively. Women with improved diet quality had favorable 4-year weight change, particularly those with a history of GDM (AHEI change [95% CI] from low to high −2.97 kg [−4.34, −1.60] vs. −1.19 kg [−1.41, −0.96] for GDM vs. non-GDM, respectively; P heterogeneity = 0.04). Increasing PA was associated with weight maintenance for GDM women only (PA increase [95% CI] from low to high 0.26 kg [−0.25, 0.77] vs. 0.90 kg [0.80, 1.01] for GDM vs. non-GDM, respectively; P heterogeneity = 0.02). For both GDM and non-GDM women, weight change did not differ significantly with change in alcohol consumption, while women who quit smoking had significant weight gain (4.38 kg for GDM and 3.85 kg for non-GDM). CONCLUSIONS Improvements in diet quality and PA were related to less weight gain in midlife among parous women, and the benefit of such improvements on weight management was particularly pronounced among women with a history of GDM.

OBJECTIVE To investigate the association between intakes of n-6 polyunsaturated fatty acids (PUFAs) and type 2 diabetes risk in three prospective cohort studies of U.S. men and women. RESEARCH DESIGN AND METHODS We followed 83,648 women from the Nurses’ Health Study (NHS) (1980–2012), 88,610 women from NHSII (1991–2013), and 41,771 men from the Health Professionals Follow-Up Study (HPFS) (1986–2012). Dietary data were collected every 2–4 years by using validated food-frequency questionnaires. Self-reported incident diabetes, identified biennially, was confirmed by using a validated supplementary questionnaire. RESULTS During 4.93 million person-years of follow-up, 18,442 type 2 diabetes cases were documented. Dietary n-6 PUFAs accounted for 4.4–6.8% of total energy, on average, and consisted primarily of linoleic acid (LA) (≥98%). In multivariate-adjusted models, hazard ratios (95% CIs) of type 2 diabetes risk comparing extreme n-6 PUFA quintiles (highest vs. lowest) were 0.91 (0.85, 0.96) (Ptrend = 0.002) for total n-6 PUFAs and 0.92 (0.87, 0.98) (Ptrend = 0.01) for LA. In an isocaloric substitution model, diabetes risk was 14% (95% CI 5%, 21%) (P = 0.002) lower when LA isocalorically replaced saturated fats (5% of energy), 17% (95% CI 9%, 24%) (P < 0.001) lower for trans fats (2% of energy), or 9% (95% CI 17%, 0.1%) (P = 0.047) lower for carbohydrates (5% of energy). Replacing n-3 PUFAs or monounsaturated fats with LA was not significantly associated with type 2 diabetes risk. CONCLUSIONS Our study provides additional evidence that LA intake is inversely associated with risk of type 2 diabetes, especially when replacing saturated fatty acids, trans fats, or carbohydrates.

Objective: To examine whether proinflammatory and hyperinsulinemic diets are associated with increased risk of type 2 diabetes. Research Design and Methods: We prospectively followed 74,767 women from the Nurses’ Health Study (1984-2016), 90,786 women from the Nurses’ Health Study 2 (1989-2017), and 39,442 men from the Health Professionals Follow-up Study (1986-2016). Using repeated measures of food frequency questionnaires, we calculated empirical dietary inflammatory pattern (EDIP) and empirical dietary index for hyperinsulinemia (EDIH) scores which are food-based indices that characterize dietary inflammatory or insulinemic potential based on circulating biomarkers of inflammation or C-peptide. Diagnoses of type 2 diabetes were confirmed by validated supplementary questionnaires. Results: We documented 19,666 incident type 2 diabetes cases over 4.9 million person-years of follow-up. In the pooled multivariable-adjusted analyses, individuals in the highest EDIP or EDIH quintile had 3.11 times (95% CI, 2.96-3.27) and 3.40 times (95% CI, 3.23-3.58) higher type 2 diabetes risk, respectively, compared to those in the lowest quintile. Additional adjustment for body mass index (BMI) attenuated the associations (Hazard ratio, 1.95; 95% CI, 1.85-2.05 for EDIP; Hazard ratio, 1.87; 95% CI, 1.78-1.98 for EDIH), suggesting adiposity partly mediates the observed associations. Moreover, individuals in both highest EDIP and EDIH quintiles had 2.34 times higher type 2 diabetes risk (95% CI, 2.17-2.52), compared to those in both lowest quintiles, after adjustment for BMI. Conclusions: Higher dietary inflammatory and insulinemic potential were associated with an increased type 2 diabetes incidence. Findings suggest that inflammation and hyperinsulinemia are potential mechanisms linking dietary patterns and type 2 diabetes development.

Objective: Coffee may protect against multiple chronic diseases, particularly type 2 diabetes, but the mechanisms remain unclear. Research Design and Methods: Leveraging dietary and metabolomic data in two large cohorts of women (the Nurses’ Health Study I and II), we identified and validated plasma metabolites associated with coffee intake in 1595 women. We then evaluated the prospective association of coffee-related metabolites with diabetes risk and the added predictivity of these metabolites for diabetes in two nested case-control studies (n=457 cases and 1371 controls). Results: Of 461 metabolites, 34 were identified and validated to be associated with total coffee intake, including 13 positive associations (primarily trigonelline, polyphenol metabolites, and caffeine metabolites) and 21 inverse associations (primarily triacylglycerols and diacylglycerols). These associations were generally consistent for caffeinated and decaffeinated coffee, except for caffeine and its metabolites that were only associated with caffeinated coffee intake. The three cholesteryl esters positively associated with coffee intake showed inverse associations with diabetes risk, whereas the 12 metabolites negatively associated with coffee (five diacylglycerols and seven triacylglycerols) showed positive associations with diabetes. Adding the 15 diabetes-associated metabolites to classical risk factors-based prediction model increased the C-statistic from 0.79 (95% CI: 0.76, 0.83) to 0.83 (95% CI: 0.80, 0.86) (P Conclusion: Coffee consumption is associated with widespread metabolic changes, among which lipid metabolites may be critical for the anti- diabetes benefit of coffee. Coffee-related metabolites might help improve prediction of diabetes, but further validation studies are needed.

Salivary amylase, encoded by the AMY1 gene, is responsible for the digestion of carbohydrates. We investigated associations of the AMY1 genetic variations with general and central adiposity changes considering dietary carbohydrate intake among 32054 adults from 4 prospective cohort studies. A genetic risk score (GRS) was calculated based on nine AMY1 single-nucleotide polymorphisms, with higher AMY1-GRS indicating higher activity of salivary amylase. We meta-analyzed interactions between AMY1-GRS and dietary intake for changes in general and central adiposity over 5.5–10 years. We found that carbohydrate food intake significantly altered associations of AMY1-GRS with changes in body mass index (Pinteraction=0.001) and waist circumference (Pinteraction AMY1-GRS with changes in weight (Pinteraction=0.023) and waist circumference (Pinteraction=0.037) were significantly modified by carbohydrate intake. Our results suggest the importance of precision nutrition strategies considering participants’ genetic adaptation to carbohydrate-rich diets in regulating general and central adiposity.

Numerous studies have investigated individual biomarkers in relation to risk of type 2 diabetes. However, few have considered the interconnectivity of these biomarkers in the etiology of diabetes as well as the potential changes in the biomarker correlation network during diabetes development. We conducted a secondary analysis of 27 plasma biomarkers representing glucose metabolism, inflammation, adipokines, endothelial dysfunction, IGF axis, and iron store plus age and BMI at blood collection from an existing case-control study nested in the Nurses’ Health Study (NHS), including 1,303 incident diabetes case subjects and 1,627 healthy women. A correlation network was constructed based on pairwise Spearman correlations of the above factors that were statistically different between case and noncase subjects using permutation tests (P < 0.0005). We further evaluated the network structure separately among diabetes case subjects diagnosed 10 years after blood collection versus noncase subjects. Although pairwise biomarker correlations tended to have similar directions comparing diabetes case subjects to noncase subjects, most correlations were stronger in noncase than in case subjects, with the largest differences observed for the insulin/HbA1c and leptin/adiponectin correlations. Leptin and soluble leptin receptor were two hubs of the network, with large numbers of different correlations with other biomarkers in case versus noncase subjects. When examining the correlation network by timing of diabetes onset, there were more perturbations in the network for case subjects diagnosed >10 years versus

OBJECTIVE Specific lipid molecular changes leading to type 2 diabetes (T2D) are largely unknown. We assessed lipidome factors associated with future occurrence of T2D in a population at high cardiovascular risk. RESEARCH DESIGN AND METHODS We conducted a case-cohort study nested within the PREDIMED trial, with 250 incident T2D cases diagnosed during 3.8 years of median follow-up, and a random sample of 692 participants (639 noncases and 53 overlapping cases) without T2D at baseline. We repeatedly measured 207 plasma known lipid metabolites at baseline and after 1 year of follow-up. We built combined factors of lipid species using principal component analysis and assessed the association between these lipid factors (or their 1-year changes) and T2D incidence. RESULTS Baseline lysophosphatidylcholines and lysophosphatidylethanolamines (lysophospholipids [LPs]), phosphatidylcholine-plasmalogens (PC-PLs), sphingomyelins (SMs), and cholesterol esters (CEs) were inversely associated with risk of T2D (multivariable-adjusted P for linear trend ≤0.001 for all). Baseline triacylglycerols (TAGs), diacylglycerols (DAGs), and phosphatidylethanolamines (PEs) were positively associated with T2D risk (multivariable-adjusted P for linear trend CONCLUSIONS Two plasma lipid profiles made up of different lipid classes were found to be associated with T2D in participants at high cardiovascular risk. A profile including LPs, PC-PLs, SMs, and CEs was associated with lower T2D risk. Another profile composed of TAGs, DAGs, and PEs was associated with higher T2D risk.

OBJECTIVE To examine open-flame and/or high-temperature cooking (grilling/barbecuing, broiling, or roasting) and doneness preferences (rare, medium, or well done) for red meat, chicken, and fish in relation to type 2 diabetes (T2D) risk among U.S. adults who consumed animal flesh regularly (≥2 servings/week). RESEARCH DESIGN AND METHODS The prospective studies included 52,752 women from the Nurses’ Health Study (NHS) (followed during 1996–2012), 60,809 women from NHS II (followed during 2001–2013), and 24,679 men from the Health Professionals Follow-Up Study (HPFS) (followed during 1996–2012) who were free of diabetes, cardiovascular disease, and cancer at baseline. Incident cases of T2D were confirmed by validated supplementary questionnaires. RESULTS We documented 7,895 incident cases of T2D during 1.74 million person-years of follow-up. After multivariate adjustments including baseline BMI and total consumption of red meat, chicken, and fish, higher frequency of open-flame and/or high-temperature cooking was independently associated with an elevated T2D risk. When comparing open-flame and/or high-temperature cooking >15 times/month with CONCLUSIONS Independent of consumption amount, open-flame and/or high-temperature cooking for both red meat and chicken is associated with an increased T2D risk among adults who consume animal flesh regularly.

OBJECTIVE To examine the association of plasma alkylresorcinol metabolite 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), a biomarker of whole-grain wheat and rye intake, with type 2 diabetes (T2D) and impaired glucose regulation (IGR) in a Chinese population. RESEARCH DESIGN AND METHODS A total of 1,060 newly diagnosed T2D patients, 736 newly diagnosed IGR patients, and 1,443 control subjects with normal glucose tolerance were recruited in the case-control study. Plasma DHPPA concentrations were determined by high-performance liquid chromatography–tandem mass spectroscopy. Multivariate logistic regression analysis was used to evaluate the independent association of plasma DHPPA concentrations with the likelihood of T2D and IGR. RESULTS After adjustment for age, sex, BMI, and family history of diabetes, the odds ratios (95% CI) of T2D and IGR were 0.57 (0.45, 0.73) and 0.66 (0.50, 0.85), respectively, comparing the lowest with the highest quartile of plasma DHPPA concentrations. Further adjustment for current smoking status, current alcohol consumption, physical activity, history of hypertension, and educational level did not change the observed association materially. Similar results were also obtained in T2D and IGR groups combined. The inverse association of plasma DHPPA with T2D persisted in stratified analyses according to age, sex, BMI, current smoking status, current alcohol consumption, physical activity, family history of diabetes, and history of hypertension. CONCLUSIONS These findings suggested that higher plasma DHPPA concentrations were associated with lower odds of T2D and IGR. Further studies are warranted to confirm these findings in prospective cohorts.

Little is known about the genetic influence on BMI trajectory throughout adulthood. We created a genetic risk score (GRS) comprising 97 adult BMI-associated variants among 9,971 women and 6,405 men of European ancestry. Serial measures of BMI were assessed from 18 (women) or 21 (men) years to 85 years of age. We also examined BMI change in early (from 18 or 21 to 45 years of age), middle (from 45 to 65 years of age), and late adulthood (from 65 to 80 years of age). GRS was positively associated with BMI across all ages, with stronger associations in women than in men. The associations increased from early to middle adulthood, peaked at 45 years of age in men and at 60 years of age in women (0.91 and 1.35 kg/m2 per 10-allele increment, respectively) and subsequently declined in late adulthood. For women, each 10-allele increment in the GRS was associated with an average BMI gain of 0.54 kg/m2 in early adulthood, whereas no statistically significant association was found for BMI change in middle or late adulthood or for BMI change in any life period in men. Our findings indicate that genetic predisposition exerts a persistent effect on adiposity throughout adult life and increases early adulthood weight gain in women.

Whether change in physical activity over time modifies the genetic susceptibility to long-term weight gain is unknown. We calculated a BMI–genetic risk score (GRS) based on 77 BMI-associated single nucleotide polymorphisms (SNPs) and a body fat percentage (BF%)-GRS based on 12 BF%-associated SNPs in 9,390 women from the Nurses’ Health Study (NHS) and 5,291 men from the Health Professionals Follow-Up Study (HPFS). We analyzed the interactions between each GRS and change in physical activity on BMI/body weight change within five 4-year intervals from 1986 to 2006 using multivariable generalized linear models with repeated-measures analyses. Both the BMI-GRS and the BF%-GRS were associated with long-term increases in BMI/weight, and change in physical activity consistently interacted with the BF%-GRS on BMI change in the NHS (P for interaction = 0.025) and HPFS (P for interaction = 0.001). In the combined cohorts, 4-year BMI change per 10-risk allele increment was −0.02 kg/m2 among participants with greatest increase in physical activity and 0.24 kg/m2 among those with greatest decrease in physical activity (P for interaction < 0.001), corresponding to 0.01 kg versus 0.63 kg weight changes every 4 years (P for interaction = 0.001). Similar but marginal interactions were observed for the BMI-GRS (P for interaction = 0.045). Our data indicate that the genetic susceptibility to weight gain may be diminished by increasing physical activity.

With this January 2017 issue, our editorial team celebrates its 5-year anniversary at the helm of Diabetes Care . In 2012, when we accepted the assignment to oversee the scientific aspects of the journal, we envisioned that the editorial for this January 2017 issue would be our opportunity to thank the American Diabetes Association (ADA) for allowing us to lead this effort, to thank our reviewers and associate editors for their tireless efforts, and to thank the readers for their valuable suggestions and ideas. However, we are now writing to inform you that those plans have been put on hold. Our editorial team has been given the opportunity to continue to guide Diabetes Care for another 2-year period. We have accepted the invitation primarily because our “team” (including the editorial committee, editorial office, and publications staff) feels we still have creative ideas to make the journal better and considerable energy to bring these ideas to fruition. Therefore, suffice it to say, we remain honored to continue to lead Diabetes Care for this extended period. It has been our custom to summarize our productivity and achievements in both the January and June issues of each year. This year we believe the trajectory of quality continues to rise. We hope you will also agree when reading the summary presented in this narrative. We feel each year’s monthly issues have surpassed the prior year’s work, and year 2016 is no exception! As we described in July of 2016, we aim to provide the readers with lagniappe—“a little something extra”! (1). This past year the editorial team took our initiative to another level devoting several monthly issues to specific clinical or research topics. A current summary of all thematic monthly issues can be found in our Diabetes Care Online Collections (http://care.diabetesjournals.org/content/diabetes-care-online-collections). In the …

Diabetes Care ’s editorial committee customarily presents a midyear report of activities and progress. At the midpoint of 2018 we can describe, in addition to a satisfying array of original scientific reports, important feature articles of current interest and a significant new initiative. In the first half of this year, the journal published several feature articles related to our core responsibility as a journal representing the American Diabetes Association (ADA). An update to the ADA’s “Standards of Medical Care in Diabetes” (Standards of Care [SOC]) appeared as a supplement to the January issue (1). The SOC is prepared by the Professional Practice Committee of the ADA and contains guidance on various aspects of care of those with or at risk for diabetes, together with summaries of published data supporting these statements. Because scientific information is accumulating faster than ever before, the ADA announced a new policy in the March 2018 issue (2). The yearly January supplement to Diabetes Care will continue as before, but the SOC will now be updated more frequently. The ADA now uses a web annotation tool to update and revise the online version throughout the year, whenever new evidence or regulatory changes merit immediate incorporation. Already in 2018 new information has been added regarding two medications recently approved by the U.S. Food and Drug Administration (semaglutide and ertugliflozin) and an update on the definitions of hypoglycemia. Changes of this kind will be communicated by the ADA through its print, online, and social media channels. Additional consensus statements and commentaries on new or controversial topics will continue to appear in Diabetes Care . Unlike the SOC, they are not official guidance statements but generally reflect the ADA’s thinking. For example, a joint statement by representatives of the ADA and the European Association for the Study of Diabetes …

OBJECTIVE Dietary interventions in patients with type 2 diabetes (T2D) are important for preventing long-term complications. Although a healthy diet is crucial, there is still uncertainty about the optimal macronutrient composition. We performed a meta-analysis comparing diets high in cis-monounsaturated fatty acids (MUFA) to diets high in carbohydrates (CHO) or in polyunsaturated fatty acids (PUFA) on metabolic risk factors in patients with T2D. RESEARCH DESIGN AND METHODS We systematically reviewed PubMed, MEDLINE, and Cochrane databases and prior systematic reviews and meta-analyses to identify interventions assessing HbA1c, fasting plasma glucose and insulin, LDL and HDL cholesterol, triglycerides, body weight, or systolic/diastolic blood pressure. Meta-analyses were conducted using both fixed- and random-effects models to calculate the weighted mean difference (WMD) and 95% CI. RESULTS We identified 24 studies totaling 1,460 participants comparing high-MUFA to high-CHO diets and 4 studies totaling 44 participants comparing high-MUFA to high-PUFA diets. When comparing high-MUFA to high-CHO diets, there were significant reductions in fasting plasma glucose (WMD −0.57 mmol/L [95% CI −0.76, −0.39]), triglycerides (−0.31 mmol/L [−0.44, −0.18]), body weight (−1.56 kg [−2.89, −0.23]), and systolic blood pressure (−2.31 mmHg [−4.13, −0.49]) along with significant increases in HDL cholesterol (0.06 mmol/L [0.02, 0.10]). When high-MUFA diets were compared with high-PUFA diets, there was a significant reduction in fasting plasma glucose (−0.87 mmol/L [−1.67, −0.07]). All of the outcomes had low to medium levels of heterogeneity, ranging from 0.0 to 69.5% for diastolic blood pressure (Phet = 0.011). CONCLUSIONS Our meta-analysis provides evidence that consuming diets high in MUFA can improve metabolic risk factors among patients with T2D.

OBJECTIVE To conduct a systematic review of cross-sectional and prospective human studies evaluating metabolite markers identified using high-throughput metabolomics techniques on prediabetes and type 2 diabetes. RESEARCH DESIGN AND METHODS We searched MEDLINE and EMBASE databases through August 2015. We conducted a qualitative review of cross-sectional and prospective studies. Additionally, meta-analyses of metabolite markers, with data estimates from at least three prospective studies, and type 2 diabetes risk were conducted, and multivariable-adjusted relative risks of type 2 diabetes were calculated per study-specific SD difference in a given metabolite. RESULTS We identified 27 cross-sectional and 19 prospective publications reporting associations of metabolites and prediabetes and/or type 2 diabetes. Carbohydrate (glucose and fructose), lipid (phospholipids, sphingomyelins, and triglycerides), and amino acid (branched-chain amino acids, aromatic amino acids, glycine, and glutamine) metabolites were higher in individuals with type 2 diabetes compared with control subjects. Prospective studies provided evidence that blood concentrations of several metabolites, including hexoses, branched-chain amino acids, aromatic amino acids, phospholipids, and triglycerides, were associated with the incidence of prediabetes and type 2 diabetes. We meta-analyzed results from eight prospective studies that reported risk estimates for metabolites and type 2 diabetes, including 8,000 individuals of whom 1,940 had type 2 diabetes. We found 36% higher risk of type 2 diabetes per study-specific SD difference for isoleucine (pooled relative risk 1.36 [1.24–1.48]; I2 = 9.5%), 36% for leucine (1.36 [1.17–1.58]; I2 = 37.4%), 35% for valine (1.35 [1.19–1.53]; I2 = 45.8%), 36% for tyrosine (1.36 [1.19–1.55]; I2 = 51.6%), and 26% for phenylalanine (1.26 [1.10–1.44]; I2 = 56%). Glycine and glutamine were inversely associated with type 2 diabetes risk (0.89 [0.81–0.96] and 0.85 [0.82–0.89], respectively; both I2 = 0.0%). CONCLUSIONS In studies using high-throughput metabolomics, several blood amino acids appear to be consistently associated with the risk of developing type 2 diabetes.

OBJECTIVE We aimed to elucidate whether potato consumption is associated with a higher risk of type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS We analyzed data in three cohorts consisting of U.S. male and female health professionals without diabetes, cardiovascular disease, and cancer at baseline: 70,773 women from the Nurses’ Health Study (1984–2010), 87,739 women from Nurses’ Health Study II (1991–2011), and 40,669 men from the Health Professionals Follow-up Study (1986–2010). Potato consumption was assessed quadrennially using validated food frequency questionnaires (FFQs), and we calculated 4-year change in potato consumption from consecutive FFQs. Self-reported T2D diagnosis was confirmed using a validated supplementary questionnaire. RESULTS During 3,988,007 person-years of follow-up, 15,362 new cases of T2D were identified. Higher consumption of total potatoes (including baked, boiled, or mashed potatoes and french fries) was significantly associated with an elevated risk for T2D: the pooled hazard ratio (HR) of T2D compared with CONCLUSIONS Greater consumption of potatoes, especially french fries, was associated with a higher T2D risk, independent of BMI and other risk factors. Replacement of potatoes with whole grains was associated with a lower T2D risk.

OBJECTIVE To study the extent to which BMI after pregnancy adds to the elevated risk of postpregnancy type 2 diabetes in women with a history of hypertensive disorders of pregnancy (HDP) (preeclampsia or gestational hypertension). RESEARCH DESIGN AND METHODS We used data from the Nurses’ Health Study II, a prospective cohort study. In women aged 45–54 years without prior gestational diabetes mellitus, we investigated the interaction between BMI and HDP history on the risk of type 2 diabetes. For clinical and public health relevance, we focused on additive interaction. The main outcome measure was the relative excess risk due to interaction calculated from multivariable Cox proportional hazards models using normal weight as the reference group. RESULTS In total, 6,563 (11.7%) of 56,159 participants had a history of HDP and 1,341 women developed type 2 diabetes during 436,333 person-years. BMI was a strong risk factor for type 2 diabetes regardless of HDP history. However, there was evidence of an additive interaction between BMI and HDP for the risk of type 2 diabetes (P = 0.004). The attributable proportion of risk due to the interaction ranged from 0.12 (95% CI −0.22, 0.46) in women who were overweight to 0.36 (95% CI 0.13, 0.59) in women with obesity class I. CONCLUSIONS Maintaining a healthy weight may be of even greater importance in women with a history of HDP, compared with other women with a history of only normotensive pregnancies, to reduce midlife risk of type 2 diabetes.

OBJECTIVE Lesbian and bisexual (LB) women are more likely than heterosexual women to exhibit risk factors for type 2 diabetes, but studies estimating the burden of type 2 diabetes among LB women are uncommon and limited to cross-sectional designs. This study investigated incidence of type 2 diabetes in LB women and heterosexual women in a large, longitudinal U.S. cohort. RESEARCH DESIGN AND METHODS Women participating in the Nurses’ Health Study II (NHS II) ages 24–44 years in 1989 were prospectively followed through 2013. Self-reported clinician diagnosis of type 2 diabetes was assessed every other year to identify incidence. Of the participants, 1,267 identified as lesbian or bisexual and 92,983 identified as heterosexual. Cox proportional hazards regression was used to model incidence of type 2 diabetes. RESULTS LB women had a 27% higher risk of developing type 2 diabetes than heterosexual women (adjusted incidence rate ratio [IRR] 1.27, 95% CI 1.05, 1.54). Differences between LB women and heterosexual women in risk of type 2 diabetes were greater during younger ages (sexual orientation–by-age interaction, P < 0.001). BMI mediated the relationship between sexual orientation and type 2 diabetes; the IRR was completely attenuated when BMI was added to the model (IRR 0.85, 95% CI 0.70, 1.03). CONCLUSIONS Findings indicate that LB women develop type 2 diabetes at younger ages than heterosexual women. Higher BMI in LB women is an important contributor to this disparity. Public health and clinical efforts to prevent, detect, and manage obesity and type 2 diabetes among LB women are warranted.

OBJECTIVE Low-carbohydrate diets (LCDs) may improve short-term glycemic control in patients with gestational diabetes mellitus (GDM), but the long-term effect on progression from GDM to type 2 diabetes mellitus (T2DM) is unknown. We aimed to examine the long-term risk of T2DM in association with a low-carbohydrate dietary pattern among women with a history of GDM. RESEARCH DESIGN AND METHODS Overall, 4,502 women with a history of GDM from the Nurses' Health Study II (NHSII) cohort, as part of the Diabetes & Women’s Health (DWH) study, were followed up from 1991 to 2011. Overall, animal, or vegetable LCD scores, which represent adherence to different low-carbohydrate dietary patterns, were calculated using diet intake information assessed every 4 years since 1991 by validated food-frequency questionnaires. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs. RESULTS We documented 722 incident cases of T2DM during 68,897 person-years of observation. The multivariable-adjusted HRs (95% CIs) of T2DM, comparing the highest with lowest quintiles, were 1.36 (1.04–1.78) for overall LCD score (P = 0.003 for trend), 1.40 (1.06–1.84) for animal LCD score (P = 0.004 for trend), and 1.19 (0.91–1.55) for vegetable LCD score (P = 0.50 for trend). CONCLUSIONS Among women with a history of GDM, a low-carbohydrate dietary pattern, particularly with high protein and fat intake mainly from animal-source foods, is associated with higher T2DM risk, whereas a low-carbohydrate dietary pattern with high protein and fat intake from plant-source foods is not significantly associated with risk of T2DM.

As obesity rates increase, so too do the risks of type 2 diabetes, cardiovascular disease, and numerous other detrimental conditions. The prevalence of obesity in U.S. adults more than doubled between 1980 and 2010, from 15.0 to 36.1%. Although this trend may be leveling off, obesity and its individual, societal, and economic costs remain of grave concern. In June 2014, a Diabetes Care Editors’ Expert Forum convened to review the state of obesity research and discuss the latest prevention initiatives and behavioral, medical, and surgical therapies. This article, an outgrowth of the forum, offers an expansive view of the obesity epidemic, beginning with a discussion of its root causes. Recent insights into the genetic and physiological factors that influence body weight are reviewed, as are the pathophysiology of obesity-related metabolic dysfunction and the concept of metabolically healthy obesity. The authors address the crucial question of how much weight loss is necessary to yield meaningful benefits. They describe the challenges of behavioral modification and predictors of its success. The effects of diabetes pharmacotherapies on body weight are reviewed, including potential weight-neutral combination therapies. The authors also summarize the evidence for safety and efficacy of pharmacotherapeutic and surgical obesity treatments. The article concludes with an impassioned call for researchers, clinicians, governmental agencies, health policymakers, and health-related industries to collectively embrace the urgent mandate to improve prevention and treatment and for society at large to acknowledge and manage obesity as a serious disease.

With the release of this issue, our editorial team is now at the 3.5-year mark in our tenure of overseeing the scientific aspects of Diabetes Care . During this time, we have done our best to keep you up to date on all changes, innovations, progress, and successes of the journal. We realize that with each issue we are responsible for providing new information to help health care professionals care for people with diabetes and to stimulate the research community in its quest for new discoveries and new treatment paradigms. At this time last year, our editorial on the status of Diabetes Care was titled “It Just Doesn’t Get Any Better … or Does It?” (1). We also questioned whether in another 12 months we would “still be asking, ‘Can it possibly get any better than this?’” With this report, we feel that question has clearly been answered in the affirmative. A new norm for excellence has been established at Diabetes Care . Over the last year, the number of new submissions reached record levels and the quality of the published articles (our primary metric) has never been higher. Moreover, the range of topics our journal covers is unlike that of any other. In the last year, we presented reports on new medications, new combinations of medications, critical reviews of safety of commercially available agents, extended outcomes of bariatric surgery, new data on the microbiome, latest developments in the artificial pancreas, staggering data on economic costs and analysis, emerging ideas on the pathogenesis of type 2 diabetes, functional imaging studies, cognitive outcomes, and corneal nerve morphology, just to name a few—the list goes on and on! The journal also disseminates Scientific Statements, Consensus Reports, and Position Statements carefully prepared by the American Diabetes Association (ADA) (see Table 1 for highlighted …

The first epigenome-wide association study of BMI identified DNA methylation at an HIF3A locus associated with BMI. We tested the hypothesis that DNA methylation variants are associated with BMI according to intake of B vitamins. In two large cohorts, we found significant interactions between the DNA methylation–associated HIF3A single nucleotide polymorphism (SNP) rs3826795 and intake of B vitamins on 10-year changes in BMI. The association between rs3826795 and BMI changes consistently increased across the tertiles of total vitamin B2 and B12 intake (all P for interaction

OBJECTIVE To evaluate racial and ethnic differences in the association between a dietary diabetes risk reduction score and incidence of type 2 diabetes in U.S. white and minority women. RESEARCH DESIGN AND METHODS We followed 156,030 non-Hispanic white (NHW), 2,026 Asian, 2,053 Hispanic, and 2,307 black women in the Nurses’ Health Study (NHS) (1980–2008) and NHS II (1991–2009). A time-updated dietary diabetes risk reduction score (range 8–32) was created by adding points corresponding with each quartile of intake of eight dietary factors (1 = highest risk; 4 = lowest risk). A higher score indicates a healthier overall diet. RESULTS We documented 10,922 incident type 2 diabetes cases in NHW, 157 in Asian, 193 in Hispanic, and 307 in black women. Multivariable-adjusted pooled hazard ratio across two cohorts for a 10th–90th percentile range difference in dietary diabetes risk reduction score was 0.49 (95% CI 0.46, 0.52) for NHW, 0.53 (0.31, 0.92) for Asian, 0.45 (0.29, 0.70) for Hispanic, 0.68 (0.47, 0.98) for black, and 0.58 (0.46, 0.74) for overall minority women (P for interaction between minority race/ethnicity and dietary score = 0.08). The absolute risk difference (cases per 1,000 person-years) for the same contrast in dietary score was −5.3 (−7.8, −2.7) for NHW, −7.2 (−22.9, 8.4) for Asian, −11.6 (−26.7, 3.5) for Hispanic, −6.8 (−19.5, 5.9) for black, and −8.0 (−15.6, −0.5) for overall minority women (P for interaction = 0.04). CONCLUSIONS A higher dietary diabetes risk reduction score was inversely associated with risk of type 2 diabetes in all racial and ethnic groups, but the absolute risk difference was greater in minority women.

With this issue, our editorial team celebrates its 4.5-year mark in overseeing the scientific aspects of Diabetes Care . As you have come to expect, we have been consistent in our attempts to update you on our progress by informing you of all the changes, innovations, and successes of the journal. We still feel that each issue provides new information that does more than provide an incremental contribution to new knowledge—it also offers providers translational perspectives that relate new findings to everyday clinical practice and poses new questions to the research community. We feel this past year has been nothing short of spectacular for the journal! A year ago, in the July 2015 issue, we titled our report “Status of Diabetes Care : New Challenges, New Concepts, New Measures—Focusing on the Future!” as we felt the journal was at that time very much on an uphill trajectory (1). In the January 2016 issue, we titled our report “Building Momentum: Taking on the Real ‘Issues’ of Diabetes Care !” (2). In that issue, we described what has become an incredibly well-received initiative at the journal: frequent special thematic monthly issues that focus on timely and important clinical care and clinical research topics. The thematic issues to date, which at that time numbered 10, were summarized in a table in the January 2016 issue (2). For example, our October 2015 issue focused on the recommendations and other guidelines for care from the American Diabetes Association (ADA) in the form of Position Statements, Scientific Statements, and Consensus Reports, described collectively as “Guiding Principles for Diabetes Care” (3). We ended the calendar year by dedicating our December 2015 issue to highlight insulin use after 90 years (4). In that issue, we provided a collection of articles that demonstrated the diversity of recent innovations in …

As the saying goes, time flies when you are having fun! So, our editorial team was surprised to find that with this issue of Diabetes Care we are celebrating our fourth year guiding the scientific aspects of Diabetes Care . It seems like just yesterday that we were introducing the team and our vision for the direction of the journal. We saw immediately that we had “issues” to address—we could easily fail to keep pace with the rapid advances in our field unless we introduced changes in our format and tactics. By this time you are very familiar with many of the changes we have put in place as we have been diligent in updating you in both the July and January issues (1,2). Thus, with this commentary, we will not review details previously provided. We will, however, focus on two initiatives that continue to grow and flourish and have exceeded our expectations. We are referring to the Diabetes Care Symposia that we coordinate and our special monthly thematic issues. Our Diabetes Care Symposium, held each year during the American Diabetes Association’s (ADA’s) Scientific Sessions, has become our editorial team’s signature event. In June 2015, we held our fourth annual symposium, which consisted of two 1-h sessions and a selected overarching theme. The first segment—in a format used for the past 2 years—was entitled “Best of Diabetes Care .” This provided brief overviews of several articles felt by the associate editors to be some of the most noteworthy original research reports published in Diabetes Care during the past year, and it has received rave reviews. The second segment of this year’s program had presentations from four selected original …

OBJECTIVE Evidence is inconsistent for the association between sulfonylurea use and risk of cardiovascular disease among patients with diabetes. We aimed to prospectively evaluate this association using the Nurses’ Health Study (NHS), a well-established cohort of U.S. women with long-term follow-up. RESEARCH DESIGN AND METHODS We followed 4,902 women (mean age 68 years) with diabetes (mean duration 11 years), but without cardiovascular disease at baseline. The use of sulfonylureas and other medications was self-reported at baseline and during the follow-up period of up to 10 years. Cox proportional hazards regression models were used to estimate the relative risk (RR) and 95% CI for the association between the sulfonylurea use and incident cardiovascular disease while accounting for potential confounders, including age, diabetes duration, diabetes-related complications, other antihyperglycemic medications, BMI, lifestyle factors, family history of cardiovascular diseases, and present chronic conditions. We also applied the propensity score stratification method to address the possibility of residual confounding. RESULTS We identified 339 incident cases of cardiovascular disease, including 191 cases of coronary heart disease (CHD) and 148 cases of stroke. A longer duration of sulfonylurea use was significantly associated with a higher risk of CHD (P for trend = 0.002); the RRs for CHD were 1.24 (95% CI 0.85–1.81) for patients who used sulfonylurea therapy for 1–5 years, 1.51 (0.94–2.42) for 6–10 years, and 2.15 (1.31–3.54) for >10 years, compared with nonusers. Compared with users of metformin monotherapy, the RR for CHD was 3.27 (1.31–8.17) for those who were treated with the combination of metformin and sulfonylurea. The analysis using propensity score stratification yielded similar results. We did not observe a significant association between sulfonylurea therapy and stroke risk. CONCLUSIONS Long-term use of sulfonylureas was associated with a significantly higher risk of developing CHD among women with diabetes.

Although both SLC30A8 rs13266634 single nucleotide polymorphism and plasma zinc concentrations have been associated with impaired glucose regulation (IGR) and type 2 diabetes (T2D), their interactions for IGR and T2D remain unclear. Therefore, to assess zinc-SLC30A8 interactions, we performed a case-control study in 1,796 participants: 218 newly diagnosed IGR patients, 785 newly diagnosed T2D patients, and 793 individuals with normal glucose tolerance. After adjustment for age, sex, BMI, family history of diabetes, and hypertension, the multivariable odds ratio (OR) of T2D associated with a 10 µg/dL higher plasma zinc level was 0.87 (95% CI 0.85–0.90). Meanwhile, the OR of SLC30A8 rs13266634 homozygous genotypes CC compared with TT was 1.53 (1.11–2.09) for T2D. Similar associations were found in IGR and IGR&T2D groups. Each 10 µg/dL increment of plasma zinc was associated with 22% (OR 0.78 [0.72–0.85]) lower odds of T2D in TT genotype carriers, 17% (0.83 [0.80–0.87]) lower odds in CT genotype carriers, and 7% (0.93 [0.90–0.97]) lower odds in CC genotype carriers (P for interaction = 0.01). Our study suggested that the C allele of rs13266634 was associated with higher odds of T2D, and higher plasma zinc was associated with lower odds. The inverse association of plasma zinc concentrations with T2D was modified by SLC30A8 rs13266634. Further studies are warranted to confirm our findings and clarify the mechanisms underlying the interaction between plasma zinc and the SLC30A8 gene in relation to T2D.

OBJECTIVE To examine urinary levels of enterolactone and enterodiol, intestinal microbial metabolites of dietary lignans, in relation to type 2 diabetes (T2D) risk. RESEARCH DESIGN AND METHODS Urinary concentrations of the lignan metabolites were assayed by liquid chromatography-mass spectrometry among 1,107 T2D and 1,107 control subjects in a nested case-control study conducted in participants from the Nurses’ Health Study (NHS) and NHSII. Subjects were free of diabetes, cardiovascular disease, and cancer at urine sample collection in 1995–2001. Incident self-reported T2D cases identified through 2008 were confirmed with a validated questionnaire. RESULTS In both cohorts, T2D subjects had significantly lower concentrations of both enterolactone and enterodiol than control subjects. After multivariate adjustment for lifestyle and dietary risk factors of T2D, urinary concentrations of enterolactone were significantly associated with a lower risk of T2D (pooled odds ratio [OR] comparing the extreme quartiles 0.62 [95% CI 0.44, 0.88], P for trend = 0.003). Higher urinary concentrations of enterodiol were also marginally significantly associated with a lower T2D risk (pooled OR comparing extreme quartiles 0.67 [95% CI 0.48, 0.96], P for trend = 0.08). When concentrations of both metabolites were combined to reflect total lignan intake, the OR was 0.70 (95% CI 0.53, 0.92) for each SD increment of total lignan metabolites. CONCLUSIONS These results indicate that lignan metabolites, especially enterolactone, are associated with a lower risk of T2D in U.S. women. Further studies are needed to replicate these findings and to explore potential mechanisms underlying the observed association.

OBJECTIVE Previous meta-analyses identified an inverse association of coffee consumption with the risk of type 2 diabetes. However, an updated meta-analysis is needed because new studies comparing the trends of association for caffeinated and decaffeinated coffee have since been published. RESEARCH DESIGN AND METHODS PubMed and Embase were searched for cohort or nested case-control studies that assessed the relationship of coffee consumption and risk of type 2 diabetes from 1966 to February 2013. A restricted cubic spline random-effects model was used. RESULTS Twenty-eight prospective studies were included in the analysis, with 1,109,272 study participants and 45,335 cases of type 2 diabetes. The follow-up duration ranged from 10 months to 20 years. Compared with no or rare coffee consumption, the relative risk (RR; 95% CI) for diabetes was 0.92 (0.90–0.94), 0.85 (0.82–0.88), 0.79 (0.75–0.83), 0.75 (0.71–0.80), 0.71 (0.65–0.76), and 0.67 (0.61–0.74) for 1–6 cups/day, respectively. The RR of diabetes for a 1 cup/day increase was 0.91 (0.89–0.94) for caffeinated coffee consumption and 0.94 (0.91–0.98) for decaffeinated coffee consumption (P for difference = 0.17). CONCLUSIONS Coffee consumption was inversely associated with the risk of type 2 diabetes in a dose-response manner. Both caffeinated and decaffeinated coffee was associated with reduced diabetes risk.

OBJECTIVE Emerging in vitro and animal evidence suggests that methylmercury could increase type 2 diabetes, but little evidence exists in humans. We aimed to prospectively determine associations of mercury exposure, as assessed by biomarker measurement, with incident diabetes. RESEARCH DESIGN AND METHODS We used neutron activation analysis to measure toenail mercury, an objective biomarker of methylmercury exposure, in 9,267 adults free of diabetes at baseline in two separate U.S. prospective cohorts. Incident diabetes was identified from biennial questionnaires and confirmed by validated supplementary questionnaire using symptoms, diagnostic tests, and medical therapy. Associations of mercury exposure with incident diabetes were assessed using Cox proportional hazards. RESULTS During mean ± SD follow-up of 19.7 ± 7.0 years, 1,010 new cases of diabetes were diagnosed. The 95th percentile of toenail mercury was 1.32 μg/g in men and 0.76 μg/g in women, corresponding to exposures ∼3.5-fold and 2-fold higher than the U.S. Environmental Protection Agency reference dose. In multivariable analyses, toenail mercury concentrations were not associated with higher incidence of diabetes in women, men, or both cohorts combined. Comparing the highest to lowest quintile of exposure, the hazard ratio (95% CI) for incident diabetes was 0.86 (0.66–1.11) in women, 0.69 (0.42–1.15) in men, and 0.77 (0.61–0.98) in the combined cohorts. Findings were similar when more extreme categories (deciles) of mercury were compared, and in analyses stratified by fish or omega-3 consumption, BMI, and age. CONCLUSIONS These findings from two separate large prospective cohorts do not support adverse effects of methylmercury on development of diabetes in men or women at usual levels of exposure seen in these populations.

OBJECTIVE Dietary protein is an important modulator of glucose metabolism. However, studies regarding the association between dietary protein intake and gestational diabetes mellitus (GDM) risk are sparse. This study was to examine the association. RESEARCH DESIGN AND METHODS Our study included 21,457 singleton pregnancies reported among 15,294 participants of the Nurses' Health Study II cohort between 1991 and 2001. Included pregnancies were free of chronic diseases before pregnancy or previous GDM. Generalized estimating equations were used to estimate the relative risks (RRs) and 95% CIs. RESULTS After adjustment for age, parity, nondietary and dietary factors, and BMI, multivariable RRs (95% CIs) comparing the highest with lowest quintiles were 1.49 (1.03–2.17) for animal protein intake and 0.69 (0.50–0.97) for vegetable protein intake. The substitution of 5% energy from vegetable protein for animal protein was associated with a 51% lower risk of GDM (RR [95% CI], 0.49 [0.29–0.84]). For major dietary protein sources, multivariable RRs (95% CIs) comparing the highest with the lowest quintiles were 2.05 (1.55–2.73) for total red meat and 0.73 (0.56–0.95) for nuts, respectively. The substitution of red meat with poultry, fish, nuts, or legumes showed a significantly lower risk of GDM. CONCLUSIONS Higher intake of animal protein, in particular red meat, was significantly associated with a greater risk of GDM. By contrast, higher intake of vegetable protein, specifically nuts, was associated with a significantly lower risk. Substitution of vegetable protein for animal protein, as well as substitution of some healthy protein sources for red meat, was associated with a lower risk of GDM.

OBJECTIVE We sought to estimate the association between intimate partner violence, a prevalent psychosocial stressor, and the incidence of type 2 diabetes in women. RESEARCH DESIGN AND METHODS In 2001, 68,376 Nurses’ Health Study II participants answered questions on physical, sexual, and psychological intimate partner violence in adulthood (age ≥18 years) and reported the years in which any abuse occurred. We used Cox proportional hazards models to estimate the associations between intimate partner violence exposures and incidence of type 2 diabetes from 2001 to 2007. We also estimated effects of duration and time since intimate partner violence on type 2 diabetes incidence. RESULTS Of 68,376 respondents, 64,732 met inclusion criteria at the 2001 baseline; of these, 23% reported lifetime physical intimate partner violence, 11% reported lifetime sexual intimate partner violence, and 8% reported moderate and CONCLUSIONS Physical intimate partner violence is modestly associated with incidence of type 2 diabetes in this population. Severe psychological violence may substantially increase type 2 diabetes risk.

OBJECTIVE To quantitatively assess the strength and shape of the association between blood 25-hydroxy vitamin D [25(OH)D] levels and incident risk of type 2 diabetes. RESEARCH DESIGN AND METHODS A systematic search of the MEDLINE and Embase databases and a hand search of references from original reports were conducted up to 31 October 2012. Prospective observational studies that assessed the association between blood levels of 25(OH)D and risk of incident type 2 diabetes were included for meta-analysis. DerSimonian and Laird’s random-effects model was used. A quadratic spline regression analysis was used to examine the shape of the association with a generalized least-squares trend test performed for the dose-response relation. RESULTS A total of 21 prospective studies involving 76,220 participants and 4,996 incident type 2 diabetes cases were included for meta-analysis. Comparing the highest to the lowest category of 25(OH)D levels, the summary relative risk for type 2 diabetes was 0.62 (95% CI 0.54–0.70). A spline regression model showed that higher 25(OH)D levels were monotonically associated with a lower diabetes risk. This inverse association did not differ by sex, duration of follow-up, study sample size, diabetes diagnostic criteria, or 25(OH)D assay method. A linear trend analysis showed that each 10 nmol/L increment in 25(OH)D levels was associated with a 4% lower risk of type 2 diabetes (95% CI 3–6; P for linear trend < 0.0001). CONCLUSIONS Our meta-analysis showed an inverse and significant association between circulating 25(OH)D levels and risk of type 2 diabetes across a broad range of blood 25(OH)D levels in diverse populations.

Fetuin-A interferes with insulin action in animal studies, but data on fetuin-A and diabetes risk in humans are sparse and the role of nonalcoholic fatty liver disease in this association is unknown. From 2000 to 2006, we prospectively identified 470 matched incident diabetes case-control pairs in the Nurses’ Health Study, for whom levels of plasma fetuin-A, alanine transaminase (ALT), and γ-glutamyltranspeptidase (GGT) were measured. After multivariate adjustment for covariates, including ALT and GGT, the odds ratio (OR) (95% CI) comparing extreme fetuin-A quintiles was 1.81 (1.07–3.06) (P for trend = 0.009). A mediational analysis showed that this positive association was largely (79.9%) explained by fasting insulin and hemoglobin A1c levels; after further adjustment of these factors, the OR (95% CI) comparing extreme quintiles was attenuated to 1.09 (0.56–2.10) (P for trend = 0.42). In addition, liver enzymes did not modify this association (P for interaction = 0.91 for ALT and 0.58 for GGT). When results from this study were pooled with those in three prior prospective investigations of the same association, a consistent, positive association was observed between high fetuin-A levels and diabetes risk: the relative risk (95% CI) comparing high versus low fetuin-A levels was 1.69 (1.39–2.05) (P for heterogeneity = 0.45). These findings suggest that plasma fetuin-A levels were independently associated with higher risk of developing type 2 diabetes.

OBJECTIVE Both stressful intrauterine milieus and genetic susceptibility have been linked to later-life diabetes risk. The current study aims to examine the interaction between low birth weight, a surrogate measure of stressful intrauterine milieus, and genetic susceptibility in relation to risk of type 2 diabetes in adulthood. RESEARCH DESIGN AND METHODS The analysis included two independent, nested case-control studies of 2,591 type 2 diabetic case subjects and 3,052 healthy control subjects. We developed two genotype scores: an obesity genotype score based on 32 BMI-predisposing variants and a diabetes genotype score based on 35 diabetes-predisposing variants. RESULTS Obesity genotype scores showed a stronger association with type 2 diabetes risk in individuals with low birth weight. In low–birth weight individuals, the multivariable-adjusted odds ratio (OR) was 2.55 (95% CI 1.34–4.84) by comparing extreme quartiles of the obesity genotype score, while the OR was 1.27 (1.04–1.55) among individuals with birth weight >2.5 kg (P for interaction = 0.017). We did not observe significant interaction between diabetes genotype scores and birth weight with regard to risk of type 2 diabetes. In a comparison of extreme quartiles of the diabetes gene score, the multivariable-adjusted OR was 3.80 (1.76–8.24) among individuals with low birth weight and 2.27 (1.82–2.83) among those with high birth weight (P for interaction = 0.16). CONCLUSIONS Our data suggest that low birth weight and genetic susceptibility to obesity may synergistically affect adulthood risk of type 2 diabetes.

Hypertension and type 2 diabetes (T2D) commonly coexist, and both conditions are major risk factors for cardiovascular disease (CVD). We aimed to examine the association between genetic predisposition to high blood pressure and risk of CVD in individuals with T2D. The current study included 1,005 men and 1,299 women with T2D from the Health Professionals Follow-up Study and Nurses’ Health Study, of whom 732 developed CVD. A genetic predisposition score was calculated on the basis of 29 established blood pressure–associated variants. The genetic predisposition score showed consistent associations with risk of CVD in men and women. In the combined results, each additional blood pressure–increasing allele was associated with a 6% increased risk of CVD (odds ratio [OR] 1.06 [95% CI 1.03–1.10]). The OR was 1.62 (1.22–2.14) for risk of CVD comparing the extreme quartiles of the genetic predisposition score. The genetic association for CVD risk was significantly stronger in patients with T2D than that estimated in the general populations by a meta-analysis (OR per SD of genetic score 1.22 [95% CI 1.10–1.35] vs. 1.10 [1.08–1.12]; I2 = 71%). Our data indicate that genetic predisposition to high blood pressure is associated with an increased risk of CVD in individuals with T2D.

Recent evidence suggests that the fat mass and obesity-associated gene (FTO) genotype may interact with dietary intakes in relation to adiposity. We tested the effect of FTO variant on weight loss in response to 2-year diet interventions. FTO rs1558902 was genotyped in 742 obese adults who were randomly assigned to one of four diets differing in the proportions of fat, protein, and carbohydrate. Body composition and fat distribution were measured by dual-energy x-ray absorptiometry and computed tomography. We found significant modification effects for intervention varying in dietary protein on 2-year changes in fat-free mass, whole body total percentage of fat mass, total adipose tissue mass, visceral adipose tissue mass, and superficial adipose tissue mass (for all interactions, P < 0.05). Carriers of the risk allele had a greater reduction in weight, body composition, and fat distribution in response to a high-protein diet, whereas an opposite genetic effect was observed on changes in fat distribution in response to a low-protein diet. Likewise, significant interaction patterns also were observed at 6 months. Our data suggest that a high-protein diet may be beneficial for weight loss and improvement of body composition and fat distribution in individuals with the risk allele of the FTO variant rs1558902.

IGF-I shares structural homology and in vitro metabolic activity with insulin. Laboratory models suggest that IGF-I and its binding proteins IGFBP-1 and IGFBP-2 have potentially beneficial effects on diabetes risk, whereas IGFBP-3 may have adverse effects. We therefore conducted a prospective nested case-control investigation of incident diabetes (n = 742 case subjects matched 1:1 to control subjects) and its associations with IGF-axis protein levels in the Nurses’ Health Study, a cohort of middle-aged women. The median time to diabetes was 9 years. Statistical analyses were adjusted for multiple risk factors, including insulin and C-reactive protein. Diabetes risk was fivefold lower among women with baseline IGFBP-2 levels in the top versus bottom quintile (odds ratio [OR]q5–q1 = 0.17 [95% CI 0.08–0.35]; P trend < 0.0001) and was also negatively associated with IGFBP-1 levels (ORq5–q1 = 0.37 [0.18–0.73]; P trend = 0.0009). IGFBP-3 was positively associated with diabetes (ORq5–q1 = 2.05 [1.20–3.51]; P trend = 0.002). Diabetes was not associated with total IGF-I levels, but free IGF-I and diabetes had a significant association that varied (P interaction = 0.003) by insulin levels above the median (ORq5–q1 = 0.48 [0.26–0.90]; P trend = 0.0001) versus below the median (ORq5–q1 = 2.52 [1.05–6.06]; P trend < 0.05). Thus, this prospective study found strong associations of incident diabetes with baseline levels of three IGFBPs and free IGF-I, consistent with hypotheses that the IGF axis might influence diabetes risk.

OBJECTIVE Examine the association of prepregnancy habitual consumption of fruits and fruit juices and gestational diabetes mellitus (GDM) risk. RESEARCH DESIGN AND METHODS A prospective study among women with at least one singleton pregnancy in the Nurses’ Health Study II from 1991 to 2001. RESULTS Among 13,475 women, 860 reported a first diagnosis of GDM. The adjusted relative risks (RRs) for GDM from the lowest to highest quintile of whole fruit consumption were 1.00 (referent), 0.80 (95% CI 0.65–0.98), 0.90 (0.73–1.10), 0.80 (0.64–1.00), and 0.93 (0.76–1.16), respectively. The corresponding RRs for fruit juice were 1.00, 0.82 (0.66–1.01), 0.78 (0.63–0.96), 0.84 (0.68–1.04), and 1.00 (0.81–1.23). CONCLUSIONS These data suggest that prepregnancy higher consumption of whole fruits is not associated with an increased GDM risk. The association between fruit juices and GDM risk appears to be nonlinear.

OBJECTIVE Epidemiological studies have repeatedly investigated the association between depression and metabolic syndrome (MetS). However, the results have been inconsistent. This meta-analysis aimed to summarize the current evidence from cross-sectional and prospective cohort studies that evaluated this association. RESEARCH DESIGN AND METHODS MEDLINE, EMBASE, and PsycINFO databases were searched for articles published up to January 2012. Cross-sectional and cohort studies that reported an association between the two conditions in adults were included. Data on prevalence, incidence, unadjusted or adjusted odds ratio (OR), and 95% CI were extracted or provided by the authors. The pooled OR was calculated separately for cross-sectional and cohort studies using random-effects models. The I2 statistic was used to assess heterogeneity. RESULTS The search yielded 29 cross-sectional studies (n = 155,333): 27 studies reported unadjusted OR with a pooled estimate of 1.42 (95% CI 1.28–1.57; I2 = 55.1%); 11 studies reported adjusted OR with depression as the outcome (1.27 [1.07–1.57]; I2 = 60.9%), and 12 studies reported adjusted OR with MetS as the outcome (1.34 [1.18–1.51]; I2 = 0%). Eleven cohort studies were found (2 studies reported both directions): 9 studies (n = 26,936 with 2,316 new-onset depression case subjects) reported adjusted OR with depression as the outcome (1.49 [1.19–1.87]; I2 = 56.8%), 4 studies (n = 3,834 with 350 MetS case subjects) reported adjusted OR with MetS as the outcome (1.52 [1.20–1.91]; I2 = 0%). CONCLUSIONS Our results indicate a bidirectional association between depression and MetS. These results support early detection and management of depression among patients with MetS and vice versa.

OBJECTIVE To investigate the association between vitamin D status, assessed by plasma 25-hydroxyvitamin D, and risk of incident diabetes. RESEARCH DESIGN AND METHODS Prospective observational study with a mean follow-up of 2.7 years in the Diabetes Prevention Program (DPP), a multicenter trial comparing different strategies for prevention of diabetes in patients with prediabetes. We assessed the association between plasma 25-hydroxyvitamin D, measured repeatedly during follow-up, and incident diabetes in the combined placebo (n = 1,022) and intensive lifestyle (n = 1,017) randomized arms of the DPP. Variables measured at multiple study time points (25-hydroxyvitamin D, BMI, and physical activity) entered the analyses as time-varying “lagged” covariates, as the mean of the previous and current visits at which diabetes status was assessed. RESULTS After multivariate adjustment, including for the DPP intervention, participants in the highest tertile of 25-hydroxyvitamin D (median concentration, 30.1 ng/mL) had a hazard ratio of 0.72 (95% CI 0.56–0.90) for developing diabetes compared with participants in the lowest tertile (median concentration, 12.8 ng/mL). The association was in the same direction in placebo (0.70; 0.52–0.94) versus lifestyle arm (0.80; 0.54–1.17). CONCLUSIONS Higher plasma 25-hydroxyvitamin D, assessed repeatedly, was associated with lower risk of incident diabetes in high-risk patients, after adjusting for lifestyle interventions (dietary changes, increased physical activity, and weight loss) known to decrease diabetes risk. Because of the observational nature of the study, the potential association between vitamin D and diabetes needs to be confirmed in intervention studies.

Dyslipidemia has been associated with type 2 diabetes, but it remains unclear whether dyslipidemia plays a causal role in type 2 diabetes. We aimed to examine the association between the genetic predisposition to dyslipdemia and type 2 diabetes risk. The current study included 2,447 patients with type 2 diabetes and 3,052 control participants of European ancestry from the Nurses’ Health Study and the Health Professionals Follow-up Study. Genetic predisposition to dyslipidemia was estimated by three genotype scores of lipids (LDL cholesterol, HDL cholesterol, and triglycerides) on the basis of the established loci for blood lipids. Linear relation analysis indicated that the HDL cholesterol and triglyceride genotype scores, but not the LDL cholesterol genotype score, were linearly related to elevated type 2 diabetes risk. Each point of the HDL cholesterol and triglyceride genotype scores was associated with a 3% (odds ratio [OR] 1.03 [95% CI 1.01–1.04]) and a 2% (1.02 [1.00–1.04]) increased risk of developing type 2 diabetes, respectively. The ORs were 1.39 (1.17–1.65) and 1.19 (1.01–1.41) for type 2 diabetes by comparing extreme quartiles of the HDL cholesterol genotype score and triglyceride genotype score, respectively. In conclusion, genetic predisposition to low HDL cholesterol or high triglycerides is related to elevated type 2 diabetes risk.

OBJECTIVE Whether dietary habits early in life can affect risk of type 2 diabetes (T2DM) in adulthood is unknown. We evaluated the relationship between dietary patterns during adolescence and risk of T2DM in midlife. RESEARCH DESIGN AND METHODS We examined the 7-year incidence of T2DM in relation to dietary patterns during high school among 37,038 participants in the Nurses’ Health Study II cohort, who completed a food-frequency questionnaire about their diet during high school. Dietary patterns were derived by factor analysis. Cox proportional hazards regression was used to estimate relative risk (RR) and 95% CI. RESULTS The prudent pattern, characterized by healthy foods, was not associated with risk of T2DM. The Western pattern, characterized by desserts, processed meats, and refined grains, was associated with 29% greater risk of T2DM (RR 1.29; 95% CI 1.00–1.66; P trend 0.04), after adjusting for high school and adult risk factors comparing extreme quintiles, but was attenuated after adjusting for adult weight change (1.19; 0.92–1.54). Women who had high Western pattern scores in high school and adulthood had an elevated risk of T2DM compared with women who had consistent low scores (1.82; 1.35–2.45), and this association was partly mediated by adult BMI (1.15; 0.85–1.56). CONCLUSIONS A Western dietary pattern during adolescence may increase risk of T2DM in later life, partly through adult weight gain. Preventive measures should be aimed at developing healthy dietary habits that begin in early life and continue through adulthood.