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Featured researches published by Stuart R. Warren.


The New England Journal of Medicine | 2009

Glucose Control and Vascular Complications in Veterans with Type 2 Diabetes

William C. Duckworth; Carlos Abraira; Thomas E. Moritz; Domenic J. Reda; Nicholas V. Emanuele; Franklin J. Zieve; Jennifer B. Marks; Stephen N. Davis; Rodney A. Hayward; Stuart R. Warren; Steven A. Goldman; Madeline McCarren; Mary Ellen Vitek; William G. Henderson; Grant D. Huang

BACKGROUND The effects of intensive glucose control on cardiovascular events in patients with long-standing type 2 diabetes mellitus remain uncertain. METHODS We randomly assigned 1791 military veterans (mean age, 60.4 years) who had a suboptimal response to therapy for type 2 diabetes to receive either intensive or standard glucose control. Other cardiovascular risk factors were treated uniformly. The mean number of years since the diagnosis of diabetes was 11.5, and 40% of the patients had already had a cardiovascular event. The goal in the intensive-therapy group was an absolute reduction of 1.5 percentage points in the glycated hemoglobin level, as compared with the standard-therapy group. The primary outcome was the time from randomization to the first occurrence of a major cardiovascular event, a composite of myocardial infarction, stroke, death from cardiovascular causes, congestive heart failure, surgery for vascular disease, inoperable coronary disease, and amputation for ischemic gangrene. RESULTS The median follow-up was 5.6 years. Median glycated hemoglobin levels were 8.4% in the standard-therapy group and 6.9% in the intensive-therapy group. The primary outcome occurred in 264 patients in the standard-therapy group and 235 patients in the intensive-therapy group (hazard ratio in the intensive-therapy group, 0.88; 95% confidence interval [CI], 0.74 to 1.05; P=0.14). There was no significant difference between the two groups in any component of the primary outcome or in the rate of death from any cause (hazard ratio, 1.07; 95% CI, 0.81 to 1.42; P=0.62). No differences between the two groups were observed for microvascular complications. The rates of adverse events, predominantly hypoglycemia, were 17.6% in the standard-therapy group and 24.1% in the intensive-therapy group. CONCLUSIONS Intensive glucose control in patients with poorly controlled type 2 diabetes had no significant effect on the rates of major cardiovascular events, death, or microvascular complications with the exception of progression of albuminuria (P = 0.01) [added]. (ClinicalTrials.gov number, NCT00032487.)


The New England Journal of Medicine | 2013

Combined Angiotensin Inhibition for the Treatment of Diabetic Nephropathy

Linda F. Fried; Nicholas V. Emanuele; Jane H. Zhang; Mary T. Brophy; Todd A. Conner; William C. Duckworth; David J. Leehey; Peter A. McCullough; Theresa Z. O'Connor; Paul M. Palevsky; Robert F. Reilly; Stephen L. Seliger; Stuart R. Warren; Suzanne Watnick; Peter Peduzzi; Peter Guarino

BACKGROUND Combination therapy with angiotensin-converting-enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs) decreases proteinuria; however, its safety and effect on the progression of kidney disease are uncertain. Methods We provided losartan (at a dose of 100 mg per day) to patients with type 2 diabetes, a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 300, and an estimated glomerular filtration rate (GFR) of 30.0 to 89.9 ml per minute per 1.73 m(2) of body-surface area and then randomly assigned them to receive lisinopril (at a dose of 10 to 40 mg per day) or placebo. The primary end point was the first occurrence of a change in the estimated GFR (a decline of ≥ 30 ml per minute per 1.73 m(2) if the initial estimated GFR was ≥ 60 ml per minute per 1.73 m(2) or a decline of ≥ 50% if the initial estimated GFR was <60 ml per minute per 1.73 m(2)), end-stage renal disease (ESRD), or death. The secondary renal end point was the first occurrence of a decline in the estimated GFR or ESRD. Safety outcomes included mortality, hyperkalemia, and acute kidney injury. Results The study was stopped early owing to safety concerns. Among 1448 randomly assigned patients with a median follow-up of 2.2 years, there were 152 primary end-point events in the monotherapy group and 132 in the combination-therapy group (hazard ratio with combination therapy, 0.88; 95% confidence interval [CI], 0.70 to 1.12; P=0.30). A trend toward a benefit from combination therapy with respect to the secondary end point (hazard ratio, 0.78; 95% CI, 0.58 to 1.05; P=0.10) decreased with time (P=0.02 for nonproportionality). There was no benefit with respect to mortality (hazard ratio for death, 1.04; 95% CI, 0.73 to 1.49; P=0.75) or cardiovascular events. Combination therapy increased the risk of hyperkalemia (6.3 events per 100 person-years, vs. 2.6 events per 100 person-years with monotherapy; P<0.001) and acute kidney injury (12.2 vs. 6.7 events per 100 person-years, P<0.001). Conclusions Combination therapy with an ACE inhibitor and an ARB was associated with an increased risk of adverse events among patients with diabetic nephropathy. (Funded by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research and Development; VA NEPHRON-D ClinicalTrials.gov number, NCT00555217.).


Circulation | 2009

Randomized Trial of Warfarin, Aspirin, and Clopidogrel in Patients With Chronic Heart Failure: The Warfarin and Antiplatelet Therapy in Chronic Heart Failure (WATCH) Trial

Barry M. Massie; Joseph F. Collins; Susan E. Ammon; Paul W. Armstrong; John G.F. Cleland; Michael D. Ezekowitz; Syed M. Jafri; William F. Krol; Christopher M. O'Connor; Kevin A. Schulman; Koon K. Teo; Stuart R. Warren

Background— Chronic heart failure remains a major cause of mortality and morbidity. The role of antithrombotic therapy in patients with chronic heart failure has long been debated. The objective of this study was to determine the optimal antithrombotic agent for heart failure patients with reduced ejection fractions who are in sinus rhythm. Methods and Results— This prospective, randomized clinical trial of open-label warfarin (target international normalized ratio of 2.5 to 3.0) and double-blind treatment with either aspirin (162 mg once daily) or clopidogrel (75 mg once daily) had a 30-month enrollment period and a minimum of 12 months of treatment. We enrolled 1587 men and women ≥18 years of age with symptomatic heart failure for at least 3 months who were in sinus rhythm and had left ventricular ejection fraction of ≤35%. The primary outcome was the time to first occurrence of death, nonfatal myocardial infarction, or nonfatal stroke. For the primary composite end point, the hazard ratios were as follows: for warfarin versus aspirin, 0.98 (95% CI, 0.86 to 1.12; P=0.77); for clopidogrel versus aspirin, 1.08 (95% CI, 0.83 to 1.40; P=0.57); and for warfarin versus clopidogrel, 0.89 (95% CI, 0.68 to 1.16; P=0.39). Warfarin was associated with fewer nonfatal strokes than aspirin or clopidogrel. Hospitalization for worsening heart failure occurred in 116 (22.2%), 97 (18.5%), and 89 (16.5%) patients treated with aspirin, clopidogrel, and warfarin, respectively (P=0.02 for warfarin versus aspirin). Conclusion— The primary outcome measure and the mortality data do not support the primary hypotheses that warfarin is superior to aspirin and that clopidogrel is superior to aspirin.


The New England Journal of Medicine | 2013

Therapies for Active Rheumatoid Arthritis after Methotrexate Failure

James R. O'Dell; Ted R. Mikuls; Thomas H. Taylor; Vandana Ahluwalia; Mary T. Brophy; Stuart R. Warren; Robert A. Lew; Amy C. Cannella; Gary Kunkel; Ciaran S. Phibbs; Aslam H. Anis; Sarah Leatherman; Edward C. Keystone

BACKGROUND Few blinded trials have compared conventional therapy consisting of a combination of disease-modifying antirheumatic drugs with biologic agents in patients with rheumatoid arthritis who have active disease despite treatment with methotrexate--a common scenario in the management of rheumatoid arthritis. METHODS We conducted a 48-week, double-blind, noninferiority trial in which we randomly assigned 353 participants with rheumatoid arthritis who had active disease despite methotrexate therapy to a triple regimen of disease-modifying antirheumatic drugs (methotrexate, sulfasalazine, and hydroxychloroquine) or etanercept plus methotrexate. Patients who did not have an improvement at 24 weeks according to a prespecified threshold were switched in a blinded fashion to the other therapy. The primary outcome was improvement in the Disease Activity Score for 28-joint counts (DAS28, with scores ranging from 2 to 10 and higher scores indicating more disease activity) at week 48. RESULTS Both groups had significant improvement over the course of the first 24 weeks (P=0.001 for the comparison with baseline). A total of 27% of participants in each group required a switch in treatment at 24 weeks. Participants in both groups who switched therapies had improvement after switching (P<0.001), and the response after switching did not differ significantly between the two groups (P=0.08). The change between baseline and 48 weeks in the DAS28 was similar in the two groups (-2.1 with triple therapy and -2.3 with etanercept and methotrexate, P=0.26); triple therapy was noninferior to etanercept and methotrexate, since the 95% upper confidence limit of 0.41 for the difference in change in DAS28 was below the margin for noninferiority of 0.6 (P=0.002). There were no significant between-group differences in secondary outcomes, including radiographic progression, pain, and health-related quality of life, or in major adverse events associated with the medications. CONCLUSIONS With respect to clinical benefit, triple therapy, with sulfasalazine and hydroxychloroquine added to methotrexate, was noninferior to etanercept plus methotrexate in patients with rheumatoid arthritis who had active disease despite methotrexate therapy. (Funded by the Cooperative Studies Program, Department of Veterans Affairs Office of Research and Development, and others; CSP 551 RACAT ClinicalTrials.gov number, NCT00405275.)


Clinical Journal of The American Society of Nephrology | 2009

Design of Combination Angiotensin Receptor Blocker and Angiotensin-Converting Enzyme Inhibitor for Treatment of Diabetic Nephropathy (VA NEPHRON-D)

Linda F. Fried; William C. Duckworth; Jane Hongyuan Zhang; Theresa Z. O'Connor; Mary T. Brophy; Nicholas V. Emanuele; Grant D. Huang; Peter A. McCullough; Paul M. Palevsky; Stephen L. Seliger; Stuart R. Warren; Peter Peduzzi; for Va Nephron-D Investigators

Both angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) can slow the progression of diabetic nephropathy. Even with ACEI or ARB treatment, the proportion of patients who progress to end-stage renal disease (ESRD) remains high. Interventions that achieve more complete blockade of the renin-angiotensin system, such as combination ACEI and ARB, might be beneficial. This approach may decrease progression of nondiabetic kidney disease. In diabetic nephropathy, combination therapy decreases proteinuria, but its effect in slowing progression is unknown. In addition, the potential for hyperkalemia may limit the utility of combined therapy in this population. VA NEPHRON-D is a randomized, double-blind, multicenter clinical trial to assess the effect of combination losartan and lisinopril, compared with losartan alone, on the progression of kidney disease in 1850 patients with diabetes and overt proteinuria. The primary endpoints are time to (1) reduction in estimated GFR (eGFR) of > 50% (if baseline < 60 ml/min/1.73 m(2)); (2) reduction in eGFR of 30 ml/min/1.73 m(2) (if baseline > or = 60 ml/min/1.73 m(2)); (3) progression to ESRD (need for dialysis, renal transplant, or eGFR < 15 ml/min/1.73 m(2)); or (4) death. The secondary endpoint is time to change in eGFR or ESRD. Tertiary endpoints are cardiovascular events, slope of change in eGFR, and change in albuminuria at 1 yr. Specific safety endpoints are serious hyperkalemia (potassium > 6 mEq/L, requiring admission, emergency room visit, or dialysis), all-cause mortality, and other serious adverse events. This paper discusses the design and key methodological issues that arose during the planning of the study.


Circulation | 2009

DITPA (3,5-diiodothyropropionic acid), a thyroid hormone analog to treat heart failure: Phase II trial veterans affairs cooperative study

Steven A. Goldman; Madeline McCarren; Eugene Morkin; Paul W. Ladenson; Robert Edson; Stuart R. Warren; Janet Ohm; Hoang Thai; Lori Churby; Jamie Barnhill; Terrence X O'Brien; Inder S. Anand; Alberta Warner; Brack G. Hattler; Mark E. Dunlap; John M. Erikson; Mei Chiung Shih; Phil Lavori

Background— In animal studies and a pilot trial in patients with congestive heart failure, the thyroid hormone analog 3,5 diiodothyropropionic acid (DITPA) had beneficial hemodynamic effects. Methods and Results— This was a phase II multicenter, randomized, placebo-controlled, double-blind trial of New York Heart Association class II to IV congestive heart failure patients randomized (2:1) to DITPA or placebo and treated for 6 months. The study enrolled 86 patients (n=57 to DITPA, n=29 to placebo). The primary objective was to assess the effect of DITPA on a composite congestive heart failure end point that classifies patients as improved, worsened, or unchanged based on symptom changes and morbidity/mortality. DITPA was poorly tolerated, which obscured the interpretation of congestive heart failure–specific effects. Fatigue and gastrointestinal complaints, in particular, were more frequent in the DITPA group. DITPA increased cardiac index (by 18%) and decreased systemic vascular resistance (by 11%), serum cholesterol (−20%), low-density lipoprotein cholesterol (−30%), and body weight (−11 lb). Thyroid-stimulating hormone was suppressed in patients given DITPA, which reflects its thyromimetic effect; however, no symptoms or signs of potential hypothyroidism or thyrotoxicosis were seen. Conclusions— DITPA improved some hemodynamic and metabolic parameters, but there was no evidence for symptomatic benefit in congestive heart failure.


The Journal of Urology | 2009

Intravenous Zoledronic Acid to Prevent Osteoporosis in a Veteran Population With Multiple Risk Factors for Bone Loss on Androgen Deprivation Therapy

Nirmala Bhoopalam; Steven C. Campbell; Thomas E. Moritz; William R. Broderick; Padmini Iyer; Anthony G. Arcenas; Peter J. Van Veldhuizen; Nicholas Friedman; Domenic J. Reda; Stuart R. Warren; Harinder Garewal

PURPOSE Androgen deprivation therapy for prostate cancer is associated with osteoporosis and increased fracture risk. Previous studies of zoledronic acid demonstrated bone loss prevention in patients initiating androgen deprivation therapy. There are limited data on patients on prolonged androgen deprivation therapy or in Veterans Affairs patients with multiple risk factors for osteoporosis. METHODS We randomized 93 patients with M0 prostate cancer in this placebo controlled trial in the Veterans Affairs health care system. Preplanned strata included 50 patients on androgen deprivation therapy for less than 1 year (stratum 1) and 43 on androgen deprivation therapy for greater than 1 year (stratum 2). In each stratum patients were randomized to 4 mg zoledronic acid intravenously every 3 months for 4 treatments or intravenous placebo. The primary end point was the percent change in bone mineral density at the lumbar spine at 12 months. RESULTS Age, race, body mass index and osteoporosis risk factors were similar for the 2 treatments. Most patients were former smokers, had moderate alcohol intake, were not on calcium/vitamin D supplements and were relatively sedentary at baseline. In stratum 1 spine bone mineral density increased 5.95% in the zoledronic acid arm and decreased 3.23% in the placebo arm (p = 0.0044). In stratum 2 spine bone mineral density increased 6.08% in the zoledronic acid arm and only increased 1.57% in the placebo arm (p = 0.0005). Treatment was well tolerated with minimal impact on renal function. CONCLUSIONS Zoledronic acid improved bone mineral density in patients with M0 prostate cancer on androgen deprivation therapy for 1 year or less, or greater than 1 year. This finding indicates that bisphosphonate therapy remains effective when initiated later in the course of androgen deprivation therapy and is efficacious in Veterans Affairs patients with multiple risk factors for osteoporosis.


American Journal of Kidney Diseases | 2009

Homocysteine Lowering and Cognition in CKD: The Veterans Affairs Homocysteine Study

Christopher B. Brady; J. Michael Gaziano; Roberta A. Cxypoliski; Peter Guarino; James S. Kaufman; Stuart R. Warren; Pamela Hartigan; David S. Goldfarb; Rex L. Jamison

BACKGROUND Individuals with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) have high plasma total homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high-dose B vitamins to decrease high tHcy levels improves cognition in persons with kidney disease is unknown. STUDY DESIGN Randomized controlled trial. SETTING & PARTICIPANTS A substudy of 659 patients (mean age, 67.3 +/- 11.7 years) who participated in a randomized double-blind clinical trial 5 years in duration conducted in 36 US Department of Veterans Affairs medical centers of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy level. 236 (35.8%) were treated by using dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance of 30 mL/min or less (advanced CKD). All had high tHcy levels (> or =15 micromol/L) at baseline. Cognitive assessments began during the follow-up period of the main trial 3 years after treatment began; participants subsequently were retested 1 year later to assess cognitive change. INTERVENTION Daily high-dose B vitamin capsule (40 mg of folic acid, 100 mg of vitamin B(6), and 2 mg of vitamin B(12)) or placebo. OUTCOMES Cognitive function at initial assessment and 1 year later. MEASUREMENTS Telephone Interview of Cognitive Status-modified, supplemented with attention, working memory, and executive function tests. RESULTS Initial cognitive function was impaired in approximately 19% of patients regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment decreased tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status 1 year later. LIMITATIONS Cognitive assessments began after treatment was initiated; cognitive assessment was limited. CONCLUSION Treatment with high daily doses of B vitamins, which decreased tHcy levels, did not affect cognitive outcomes in patients with advanced CKD and ESRD.


The Journal of Clinical Endocrinology and Metabolism | 2010

Effects of the Thyromimetic Agent Diiodothyropropionic Acid on Body Weight, Body Mass Index, and Serum Lipoproteins: A Pilot Prospective, Randomized, Controlled Study

Paul W. Ladenson; Madeline McCarren; Eugene Morkin; Robert Edson; Mei Chiung Shih; Stuart R. Warren; Jamie Barnhill; Lori Churby; Hoang Thai; Terrence X. O'Brien; Inder S. Anand; A. Warner; Brack G. Hattler; Mark E. Dunlap; John M. Erikson; Steven Goldman

CONTEXT Widespread thyroid hormone actions offer the possibility of developing selective thyromimetic analogs with salutary metabolic properties. Consequently, effects of diiodothyropropionic acid (DITPA) on body weight, serum lipoproteins, and bone metabolism markers were studied in a prospective, controlled, double-blind 24-wk trial, which was primarily designed to assess treatment of stable chronic heart failure. DESIGN Eighty-six patients (aged 66 +/- 11 yr, mean +/- sd) were randomized (1:2) to placebo or an escalating DITPA dose (90 to 180, 270, and 360 mg/d) over 8 wk until serum TSH was less than 0.02 mU/liter. Patients were studied at 2, 4, 6, 8, 16, and 24 wk and after 4 wk off study drug. Only 21 DITPA-treated and 27 placebo patients completed the full 24 wk of therapy. RESULTS DITPA therapy lowered serum TSH levels and, to a lesser extent, serum T(3) and T(4), but there were no differences in clinical manifestations of thyrotoxicosis or hypothyroidism. Serum total and low-density lipoprotein cholesterol levels both decreased on DITPA; there was a transient decrease in triglycerides and no change in high-density lipoprotein cholesterol. DITPA therapy was associated with significant reduction in body weight, 12.5 lb at 24 wk. Increases in serum osteocalcin, N-telopeptide, and deoxypyridinoline levels were consistent with increased bone turnover on DITPA. CONCLUSION This investigation of DITPA actions demonstrated its efficacy in reducing body weight and lowering total and low-density lipoprotein cholesterol levels. However, DITPAs adverse effects at doses used resulted in a high dropout rate and potentially dangerous skeletal actions were observed.


American Journal of Kidney Diseases | 2009

Original InvestigationPathogenesis and Treatment of Kidney DiseaseHomocysteine Lowering and Cognition in CKD: The Veterans Affairs Homocysteine Study

Christopher B. Brady; J. Michael Gaziano; Roberta A. Cxypoliski; Peter Guarino; James S. Kaufman; Stuart R. Warren; Pamela Hartigan; David S. Goldfarb; Rex L. Jamison

BACKGROUND Individuals with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) have high plasma total homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high-dose B vitamins to decrease high tHcy levels improves cognition in persons with kidney disease is unknown. STUDY DESIGN Randomized controlled trial. SETTING & PARTICIPANTS A substudy of 659 patients (mean age, 67.3 +/- 11.7 years) who participated in a randomized double-blind clinical trial 5 years in duration conducted in 36 US Department of Veterans Affairs medical centers of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy level. 236 (35.8%) were treated by using dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance of 30 mL/min or less (advanced CKD). All had high tHcy levels (> or =15 micromol/L) at baseline. Cognitive assessments began during the follow-up period of the main trial 3 years after treatment began; participants subsequently were retested 1 year later to assess cognitive change. INTERVENTION Daily high-dose B vitamin capsule (40 mg of folic acid, 100 mg of vitamin B(6), and 2 mg of vitamin B(12)) or placebo. OUTCOMES Cognitive function at initial assessment and 1 year later. MEASUREMENTS Telephone Interview of Cognitive Status-modified, supplemented with attention, working memory, and executive function tests. RESULTS Initial cognitive function was impaired in approximately 19% of patients regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment decreased tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status 1 year later. LIMITATIONS Cognitive assessments began after treatment was initiated; cognitive assessment was limited. CONCLUSION Treatment with high daily doses of B vitamins, which decreased tHcy levels, did not affect cognitive outcomes in patients with advanced CKD and ESRD.

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J. Michael Gaziano

Brigham and Women's Hospital

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Jamie Barnhill

University of New Mexico

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