Browsing by Author "Knowler, William C."
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Item Antidepressant Medicine Use and Risk of Developing Diabetes During the Diabetes Prevention Program and Diabetes Prevention Program Outcomes Study(2010-12) Rubin, Richard R.; Ma, Yong; Peyrot, Mark; Marrero, David G.; Price, David W.; Barrett-Connor, Elizabeth; Knowler, William C.; for the Diabetes Prevention Program Research GroupOBJECTIVE To assess the association between antidepressant medicine use and risk of developing diabetes during the Diabetes Prevention Program (DPP) and Diabetes Prevention Program Outcomes Study (DPPOS). RESEARCH DESIGN AND METHODS DPP/DPPOS participants were assessed for diabetes every 6 months and for antidepressant use every 3 months in DPP and every 6 months in DPPOS for a median 10.0-year follow-up. RESULTS Controlled for factors associated with diabetes risk, continuous antidepressant use compared with no use was associated with diabetes risk in the placebo (adjusted hazard ratio 2.34 [95% CI 1.32–4.15]) and lifestyle (2.48 [1.45–4.22]) arms, but not in the metformin arm (0.55 [0.25–1.19]). CONCLUSIONS Continuous antidepressant use was significantly associated with diabetes risk in the placebo and lifestyle arms. Measured confounders and mediators did not account for this association, which could represent a drug effect or reflect differences not assessed in this study between antidepressant users and nonusers.Item Depression as a Predictor of Weight Regain Among Successful Weight Losers in the Diabetes Prevention Program(2013-02) Price, David W.; Ma, Yong; Rubin, Richard R.; Perreault, Leigh; Bray, George A.; Marrero, David G.; Knowler, William C.; Barrett-Connor, Elizabeth; LaCoursiere, D. YvetteOBJECTIVE: To determine whether depression symptoms or antidepressant medication use predicts weight regain in overweight individuals with impaired glucose tolerance (IGT) who are successful with initial weight loss. RESEARCH DESIGN AND METHODS: A total of 1,442 participants who successfully lost at least 3% of their baseline body weight after 12 months of participation in the randomized controlled Diabetes Prevention Program (DPP) continued in their assigned treatment group (metformin, intensive lifestyle, or placebo) and were followed into the Diabetes Prevention Program Outcome Study (DPPOS). Weight regain was defined as a return to baseline DPP body weight. Participant weight and antidepressant medication use were assessed every 6 months. Depression symptoms (Beck Depression Inventory [BDI] score ≥11) were assessed every 12 months. RESULTS: Only 2.7% of the overall cohort had moderate to severe depression symptoms at baseline; most of the participants with BDI score ≥11 had only mild symptoms during the period of observation. In unadjusted analyses, both depression symptoms (hazard ratio 1.31 [95% CI 1.03-1.67], P = 0.03) and antidepressant medication use at either the previous visit (1.72 [1.37-2.15], P < 0.0001) or cumulatively as percent of visits (1.005 [1.002-1.008], P = 0.0003) were predictors of subsequent weight regain. After adjustment for multiple covariates, antidepressant use remained a significant predictor of weight regain (P < 0.0001 for the previous study visit; P = 0.0005 for the cumulative measure), while depression symptoms did not. CONCLUSIONS: In individuals with IGT who do not have severe depression and who initially lose weight, antidepressant use may increase the risk of weight regain.Item Depression Symptoms and Antidepressant Medicine Use in Diabetes Prevention Program Participants(2005-04) Rubin, Richard R.; Knowler, William C.; Ma, Yong; Marrero, David G.; Edelstein, Sharon L.; Walker, Elizabeth A.; Garfield, Sanford A.; Fisher, Edwin B.; The Diabetes Prevention Program Research GroupOBJECTIVE: To assess depression markers (symptoms and antidepressant medicine use) in Diabetes Prevention Program (DPP) participants and to determine whether changes in depression markers during the course of the study were associated with treatment arm, weight change, physical activity level, or participant demographic characteristics. RESEARCH DESIGN AND METHODS: DPP participants (n = 3,187) in three treatment arms (intensive lifestyle, metformin, and placebo) completed the Beck Depression Inventory (BDI) and reported on use of antidepressant medicines at randomization and subsequently at each annual visit (average duration in study 3.2 years). RESULTS: On study entry, 10.3% of participants had BDI scores > or =11, which was used as a threshold for mild depression, 5.7% took antidepressant medicines, and 0.9% had both depression markers. During the DPP, the proportion of participants with elevated BDI scores declined (from 10.3% at baseline to 8.4% at year 3), while the proportion taking antidepressant medicines increased (from 5.7% at baseline to 8.7% at year 3), leaving the proportion with either marker unchanged. These time trends were not significantly associated with the DPP treatment arm. Depression markers throughout the study were associated with some participant demographic factors, adjusted for other factors. Men were less likely to have elevated depression scores and less likely to use antidepressant medicine at baseline (9.0% of men and 17.9% of women had at least one marker of depression) and throughout the study (P <0.0001). Those with more education were less likely to have elevated symptom scores (P = 0.0007) but more likely to be taking antidepressant medicine (P = 0.002). Non-Hispanic white participants were less likely than African Americans to have BDI scores > or =11 (P = 0.03), but white participants were more likely to be taking antidepressant medicine than any other racial/ethnic group (P <0.0001). CONCLUSIONS: DPP participation was not associated with changes in levels of depression. Countervailing trends in the proportion of DPP participants with elevated depression symptoms and the proportion taking antidepressant medicine resulted in no significant change in the proportion with either marker. The finding that those taking antidepressant medicine often do not have elevated depression symptoms indicates the value of assessing both markers when estimating overall depression rates.Item Depressive Symptoms, Antidepressant Medication Use, and Inflammatory Markers in the Diabetes Prevention Program(Wolters Kluwer, 2018-02) de Groot, Mary; Marrero, David; Mele, Lisa Mele; Doyle, Todd; Schwartz, Frank; Mather, Kieren J.; Goldberg, Ronald; Price, David W.; Ma, Yong; Knowler, William C.; Medicine, School of MedicineOBJECTIVE: Antidepressant medication use (ADM) has been shown to predict diabetes. This article assessed the role of inflammatory markers in this relationship within the Diabetes Prevention Program (DPP). METHODS: DPP participants randomized to metformin (MET), life-style intervention (ILS), or placebo (PLB) were assessed for depression (Beck Depression Inventory [BDI]) annually, ADM use semiannually, serum inflammatory markers (C-reactive protein [CRP], interleukin 6 [IL-6]) at baseline and year 1, and diagnosis of type 2 diabetes mellitus (T2DM) semiannually (for 3.2 years). RESULTS: At baseline (N = 3187), M (SD) body mass index was 34 (6) kg/m and the median (interquartile range) BDI score was 3 (1-7). One hundred eighty-one (5.7%) reported ADM use and 328 (10%) had BDI scores of 11 or higher. CRP and IL-6 levels did not differ by treatment group. Baseline ADM, but not BDI score, was associated with higher levels of baseline CRP adjusted for demographic, anthropometric variables, and other medications (20% higher, p = .01). Year 1 CRP decreased for non-ADM users in the MET (-13.2%) and ILS (-34%) groups and ADM users in the ILS group (-29%). No associations were found with IL-6. CRP and continuous use of ADM predicted incident T2DM in the PLB group. In the ILS group, continuous and intermittent ADM, but not CRP, predicted T2DM. In the MET group, CRP predicted incident T2DM. CRP did not mediate the risk of T2DM with ADM use in any group. CONCLUSIONS: ADM was significantly associated with elevated CRP and incident T2DM. In the PLB group, ADM and CRP independently predicted onset of T2DM; however, CRP did not significantly mediate the effect of ADM.Item Elevated Depression Symptoms, Antidepressant Medicine Use, and Risk of Developing Diabetes During the Diabetes Prevention Program(2008-03) Rubin, Richard R.; Ma, Yong; Marrero, David G.; Peyrot, Mark; Barrett-Connor, Elizabeth L.; Kahn, Steven E.; Haffner, Steven M.; Price, David W.; Knowler, William C.OBJECTIVE—To assess the association between elevated depression symptoms or antidepressant medicine use on entry to the Diabetes Prevention Program (DPP) and during the study and the risk of developing diabetes during the study. RESEARCH DESIGN AND METHODS—DPP participants (n = 3,187) in three treatment arms (intensive lifestyle [ILS], metformin [MET], and placebo [PLB]) completed the Beck Depression Inventory (BDI) and reported their use of antidepressant medication at randomization and throughout the study (average duration in study 3.2 years). RESULTS—When other factors associated with the risk of developing diabetes were controlled, elevated BDI scores at baseline or during the study were not associated with diabetes risk in any arm. Baseline antidepressant use was associated with diabetes risk in the PLB (hazard ratio 2.25 [95% CI 1.38–3.66]) and ILS (3.48 [1.93–6.28]) arms. Continuous antidepressant use during the study (compared with no use) was also associated with diabetes risk in the same arms (PLB 2.60 [1.37–4.94]; ILS 3.39 [1.61–7.13]), as was intermittent antidepressant use during the study in the ILS arm (2.07 [1.18–3.62]). Among MET arm participants, antidepressant use was not associated with developing diabetes. CONCLUSIONS—A strong and statistically significant association between antidepressant use and diabetes risk in the PLB and ILS arms was not accounted for by measured confounders or mediators. If future research finds that antidepressant use independently predicts diabetes risk, efforts to minimize the negative effects of antidepressant agents on glycemic control should be pursued.Item Lifestyle and Metformin Ameliorate Insulin Sensitivity Independently of the Genetic Burden of Established Insulin Resistance Variants in Diabetes Prevention Program Participants(American Diabetes Association, 2016-02) Hivert, Marie-France; Christophi, Costas A.; Franks, Paul W.; Jablonski, Kathleen A.; Ehrmann, David A.; Kahn, Steven E.; Horton, Edward S.; Pollin, Toni I.; Mather, Kieren J.; Perreault, Leigh; Barrett-Connor, Elizabeth; Knowler, William C.; Florez, Jose C.; Department of Medicine, IU School of MedicineLarge genome-wide association studies of glycemic traits have identified genetics variants that are associated with insulin resistance (IR) in the general population. It is unknown whether people with genetic enrichment for these IR variants respond differently to interventions that aim to improve insulin sensitivity. We built a genetic risk score (GRS) based on 17 established IR variants and effect sizes (weighted IR-GRS) in 2,713 participants of the Diabetes Prevention Program (DPP) with genetic consent. We tested associations between the weighted IR-GRS and insulin sensitivity index (ISI) at baseline in all participants, and with change in ISI over 1 year of follow-up in the DPP intervention (metformin and lifestyle) and control (placebo) arms. All models were adjusted for age, sex, ethnicity, and waist circumference at baseline (plus baseline ISI for 1-year ISI change models). A higher IR-GRS was associated with lower baseline ISI (β = -0.754 [SE = 0.229] log-ISI per unit, P = 0.001 in fully adjusted models). There was no differential effect of treatment for the association between the IR-GRS on the change in ISI; higher IR-GRS was associated with an attenuation in ISI improvement over 1 year (β = -0.520 [SE = 0.233], P = 0.03 in fully adjusted models; all treatment arms). Lifestyle intervention and metformin treatment improved the ISI, regardless of the genetic burden of IR variants.Item Metabolite Profiles of Incident Diabetes and Heterogeneity of Treatment Effect in the Diabetes Prevention Program(American Diabetes Association, 2019-12) Chen, Zsu-Zsu; Liu, Jinxi; Morningstar, Jordan; Heckman-Stoddard, Brandy M.; Lee, Christine G.; Dagogo-Jack, Samuel; Ferguson, Jane F.; Hamman, Richard F.; Knowler, William C.; Mather, Kieren J.; Perreault, Leigh; Florez, Jose C.; Wang, Thomas J.; Clish, Clary; Temprosa, Marinella; Gerszten, Robert E.; Medicine, School of MedicineNovel biomarkers of type 2 diabetes (T2D) and response to preventative treatment in individuals with similar clinical risk may highlight metabolic pathways that are important in disease development. We profiled 331 metabolites in 2,015 baseline plasma samples from the Diabetes Prevention Program (DPP). Cox models were used to determine associations between metabolites and incident T2D, as well as whether associations differed by treatment group (i.e., lifestyle [ILS], metformin [MET], or placebo [PLA]), over an average of 3.2 years of follow-up. We found 69 metabolites associated with incident T2D regardless of treatment randomization. In particular, cytosine was novel and associated with the lowest risk. In an exploratory analysis, 35 baseline metabolite associations with incident T2D differed across the treatment groups. Stratification by baseline levels of several of these metabolites, including specific phospholipids and AMP, modified the effect that ILS or MET had on diabetes development. Our findings highlight novel markers of diabetes risk and preventative treatment effect in individuals who are clinically at high risk and motivate further studies to validate these interactions.Item The prevention of type 2 diabetes(2008-07) Crandall, Jill P.; Knowler, William C.; Kahn, Steven E.; Marrero, David G.; Florez, Jose C.; Bray, George A.; Haffner, Steven M.; Hoskin, Mary; Nathan, David M.; Diabetes Prevention Program Research GroupType 2 diabetes mellitus (T2DM) affects more than 7% of adults in the US and leads to substantial personal and economic burden. In prediabetic states insulin secretion and action—potential targets of preventive interventions—are impaired. In trials lifestyle modification (i.e. weight loss and exercise) has proven effective in preventing incident T2DM in high-risk groups, although weight loss has the greatest effect. Various medications (e.g. metformin, thiazolidinediones and acarbose) can also prevent or delay T2DM. Whether diabetes-prevention strategies also ultimately prevent the development of diabetic vascular complications is unknown, but cardiovascular risk factors are favorably affected. Preventive strategies that can be implemented in routine clinical settings have been developed and evaluated. Widespread application has, however, been limited by local financial considerations, even though cost-effectiveness might be achieved at the population level.Item Quantitative trait loci, G×E and G×G for glycemic traits: response to metformin and placebo in the Diabetes Prevention Program (DPP)(Springer, 2022) Maxwell, Taylor J.; Franks, Paul W.; Kahn, Steven E.; Knowler, William C.; Mather, Kieren J.; Florez, Jose C.; Jablonski, Kathleen A.; Medicine, School of MedicineThe complex genetic architecture of type-2-diabetes (T2D) includes gene-by-environment (G×E) and gene-by-gene (G×G) interactions. To identify G×E and G×G, we screened markers for patterns indicative of interactions (relationship loci [rQTL] and variance heterogeneity loci [vQTL]). rQTL exist when the correlation between multiple traits varies by genotype and vQTL occur when the variance of a trait differs by genotype (potentially flagging G×G and G×E). In the metformin and placebo arms of the DPP (n = 1762) we screened 280,965 exomic and intergenic SNPs, for rQTL and vQTL patterns in association with year one changes from baseline in glycemia and related traits (insulinogenic index [IGI], insulin sensitivity index [ISI], fasting glucose and fasting insulin). Significant (p < 1.8 × 10-7) rQTL and vQTL generated a priori hypotheses of individual G×E tests for a SNP × metformin treatment interaction and secondarily for G×G screens. Several rQTL and vQTL identified led to 6 nominally significant (p < 0.05) metformin treatment × SNP interactions (4 for IGI, one insulin, and one glucose) and 12G×G interactions (all IGI) that exceeded experiment-wide significance (p < 4.1 × 10-9). Some loci are directly associated with incident diabetes, and others are rQTL and modify a trait's relationship with diabetes (2 diabetes/glucose, 2 diabetes/insulin, 1 diabetes/IGI). rs3197999, an ISI/insulin rQTL, is a possible gene damaging missense mutation in MST1, is associated with ulcerative colitis, sclerosing cholangitis, Crohn's disease, BMI and coronary artery disease. This study demonstrates evidence for context-dependent effects (G×G & G×E) and the complexity of these T2D-related traits.Item Value of Urinary Albumin-to-Creatinine Ratio as a Predictor of Type 2 Diabetes in Pre-Diabetic Individuals(2008-12) Friedman, Allon; Marrero, David G.; Ma, Yong; Ackermann, Ronald; Narayan, KM Venkat; Barrett-Connor, Elizabeth; Watson, Karol; Knowler, William C.; Horton, Edward S.OBJECTIVE: The albumin-to-creatinine ratio (ACR) reflects urinary albumin excretion and is increasingly being accepted as an important clinical outcome predictor. Because of the great public health need for a simple and inexpensive test to identify individuals at high risk for developing type 2 diabetes, it has been suggested that the ACR might serve this purpose. We therefore determined whether the ACR could predict incident diabetes in a well-characterized cohort of pre-diabetic Americans. RESEARCH DESIGN AND METHODS: A total of 3,188 Diabetes Prevention Program (DPP) participants with a mean BMI of 34 kg/m(2) and elevated fasting glucose, impaired glucose tolerance, and baseline urinary albumin excretion measurements were followed for incident diabetes over a mean of 3.2 years. RESULTS: Of the participants, 94% manifested ACR levels below the microalbuminuria range and 21% ultimately developed diabetes during follow-up. Quartiles of ACR (median [range] within quartiles: 1, 3.0 [0.7-3.7]; 2, 4.6 [3.7-5.5]; 3, 7.1 [5.5-9.7]; and 4, 16.5 [9.7-1,578]) were positively associated with age, markers of adiposity and insulin secretion and resistance, blood pressure, and use of antihypertensive agents with antiproteinuric effects and inversely related to male sex and serum creatinine. An elevated hazard rate for developing diabetes with doubling of ACR disappeared after adjustment for covariates. Within the DPP intervention groups (placebo, lifestyle, and metformin), we found no consistent trend in incident diabetes by quartile or decile of ACR. CONCLUSIONS: An ACR at levels below the microalbuminuria range does not independently predict incident diabetes in adults at high risk of developing type 2 diabetes.