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Thomas A Buchanan, MD
Professor of Medicine
Vice Dean for Research
Director of the CTSI,
Co-Director, Diabetes and Obesity Research Institute
Endocrine Division Chief in the Department of Medicine
CSC 205 Health Sciences Campus Los Angeles
+1 323 442 1803


Thomas A. Buchanan, M.D., is Professor of Medicine, Obstetrics and Gynecology, and Physiology and Biophysics; Vice Dean for Research; Chief of the Division of Endocrinology and Diabetes in the Department of Medicine in Keck School of Medicine at the University of Southern California (USC) in Los Angeles. He is also the founding director of the Southern California Clinical and Translational Science Institute.

Scientifically, Dr. Buchanan conducts research into the etiology, pathogenesis, genetics and prevention of gestational and type 2 diabetes with a focus on diabetes in Hispanic Americans. Buchanan and colleagues have conducted longitudinal studies of high risk individuals to define patterns of change in insulin resistance and insulin secretion that lead to type 2 diabetes. Based on their findings, they then conducted the first successful type 2 diabetes prevention study in the United States. The biological information gained from that study pointed to a specific pancreatic beta cell defect that is heritable, a finding that formed the basis for a large family based study that has helped to identify the genetic basis for the metabolic abnormalities that lead to type 2 diabetes. In aggregate studies performed by Buchanan and his colleagues have contributed to important advances in clinical care for gestational diabetes and the prevention of type 2 diabetes in Hispanic Americans

Administratively, Dr. Buchanan has championed the development of clinical and translational research at USC, first through his role as director of the General Clinical Research Center (1996-2010). In 2010, he led the team that created the Southern California Clinical and Translational Science Institute, which in turn won a prestigious $56.8 million Clinical and Translational Science Award from the National Institutes of Health (NIH) to support and promote scientific discoveries and their application in real-life settings to health and health care. He built and directed one of the nation’s largest General Clinical Research Center (GCRC) programs. Since 2010, he has been director and principal investigator of USC’s new Southern California Clinical and Translational Science Institute (SC CTSI).

During his career, Dr. Buchanan has brought more than $180 million in extramural research funding to USC and the Keck School. He has been ranked as highly 1st at USC and 50th world-wide in annual NIH funding.

Dr. Buchanan received his medical degree from the University of Iowa, Iowa City, where he completed residency training in internal medicine. He completed his fellowship training in endocrinology and metabolism at Northwestern University Medical School, Chicago, Illinois.

A native of Iowa, Dr. Buchanan is an avid cyclist on the challenging Angeles Crest Highway near Los Angeles, a downhill skier and a dedicated family man.


Western Society for Clinical Investigation: Mayo Soley Award, 2014

University of California, Los Angeles: Josiah Brown Award, 2014

Irish Endocrine Society: Lilly Lecture, 2011

Association of American Physicians: Elected Member, 2006

American Diabetes Association: Distinguished Clinical Scientist Award, 2004

J Clin Endocrinol Metab: Endocrine Society-Pharmacia Award for Excellence in Published Clinical Research, 2002

University of Washington: John Ensinck Lecture, 2000

American Diabetes Association: Norbert Freinkel Award, 1999

American Diabetes Association: Chair, Council on Diabetes and Pregnancy, 1995-1997

NIH: Chair, Special Emphasis Panel, Hyperglycemia and Pregnancy Outcomes , 1995-1997

Canadian Diabetes Association: Novo-Nordisk International Lecture, 1995

Australian Diabetes Association: Medisense International Lecture, 1995

American Diabetes Association, Northern Illinois Affliate: Young Investigator Award, 1983

University of Iowa: Alpha Omega Alpha, 1978

Iowa State University: Phi Beta Kappa, 1974


. Research Gaps in Gestational Diabetes Mellitus: Executive Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop Obstet Gynecol. 2018 Jul 10. View in: PubMed

. A Cautionary Response to SMFM Statement: Pharmacological Treatment of Gestational Diabetes Am J Obstet Gynecol. 2018 Jun 27. View in: PubMed

. Maternal Type 1 Diabetes and Risk of Autism in Offspring JAMA. 2018 Jun 23. View in: PubMed

. Reply to EParkin et al. J Clin Oncol. 2018 May 30; JCO2018787754. View in: PubMed

. Longitudinal Increases in Adiposity Contribute to Worsening Adipokine Profile over Time in Mexican Americans Obesity (Silver Spring). 2018 Apr; 26(4):703-712. View in: PubMed

. Effects of Aerobic and Resistance Exercise on Metabolic Syndrome, Sarcopenic Obesity, and Circulating Biomarkers in Overweight or Obese Survivors of Breast Cancer: A Randomized Controlled Trial J Clin Oncol. 2018 Mar 20; 36(9):875-883. View in: PubMed

. Review of methods for measuring ß-cell function: Design considerations from the Restoring Insulin Secretion (RISE) Consortium Diabetes Obes Metab. 2018 Jan; 20(1):14-24. View in: PubMed

. The Association of Estrogen Receptor-ß Gene Variation With Salt-Sensitive Blood Pressure J Clin Endocrinol Metab. 2017 Nov 01; 102(11):4124-4135. View in: PubMed

. A Genome-Wide Association Study of IVGTT-Based Measures of First-Phase Insulin Secretion Refines the Underlying Physiology of Type 2 Diabetes Variants Diabetes. 2017 08; 66(8):2296-2309. View in: PubMed

. Pioglitazone is equally effective for diabetes prevention in older versus younger adults with impaired glucose tolerance Age (Dordr). 2016 Dec; 38(5-6):485-493. View in: PubMed

. Improved Performance of Dynamic Measures of Insulin Response Over Surrogate Indices to Identify Genetic Contributors of Type 2 Diabetes: The GUARDIAN Consortium Diabetes. 2016 07; 65(7):2072-80. View in: PubMed

. Diabetes Incidence and Glucose Tolerance after Termination of Pioglitazone Therapy: Results from ACT NOW J Clin Endocrinol Metab. 2016 05; 101(5):2056-62. View in: PubMed

. Ambient Air Pollutants Have Adverse Effects on Insulin and Glucose Homeostasis in Mexican Americans Diabetes Care. 2016 04; 39(4):547-54. View in: PubMed

. A prevalent caveolin-1 gene variant is associated with the metabolic syndrome in Caucasians and Hispanics Metabolism. 2015 Dec; 64(12):1674-81. View in: PubMed

. A novel insulin resistance index to monitor changes in insulin sensitivity and glucose tolerance: the ACT NOW study J Clin Endocrinol Metab. 2015 May; 100(5):1855-62. View in: PubMed

. Genetic Variants Associated With Quantitative Glucose Homeostasis Traits Translate to Type 2 Diabetes in Mexican Americans: The GUARDIAN (Genetics Underlying Diabetes in Hispanics) Consortium Diabetes. 2015 May; 64(5):1853-66. View in: PubMed

. Association of maternal diabetes with autism in offspring JAMA. 2015 Apr 14; 313(14):1425-34. View in: PubMed

. Variation in PPARG is associated with longitudinal change in insulin resistance in Mexican Americans at risk for type 2 diabetes J Clin Endocrinol Metab. 2015 Mar; 100(3):1187-95. View in: PubMed

. Racial and ethnic disparities in extremes of fetal growth after gestational diabetes mellitus Diabetologia. 2015 Feb; 58(2):272-81. View in: PubMed

. High calorie intake is associated with worsening insulin resistance and ß-cell function in Hispanic women after gestational diabetes mellitus Diabetes Care. 2014 Dec; 37(12):3294-300. View in: PubMed

. Genetic variation in MTNR1B is associated with gestational diabetes mellitus and contributes only to the absolute level of beta cell compensation in Mexican Americans Diabetologia. 2014 Jul; 57(7):1391-9. View in: PubMed

. Baseline adiponectin levels do not influence the response to pioglitazone in ACT NOW Diabetes Care. 2014 Jun; 37(6):1706-11. View in: PubMed

. Randomized controlled trial to evaluate the effects of combined progressive exercise on metabolic syndrome in breast cancer survivors: rationale, design, and methods BMC Cancer. 2014 Apr 03; 14:238. View in: PubMed

. Gestational diabetes mellitus, maternal obesity, and adiposity in offspring J Pediatr. 2014 Apr; 164(4):807-10. View in: PubMed

. Insulin sensitivity and insulin clearance are heritable and have strong genetic correlation in Mexican Americans Obesity (Silver Spring). 2014 Apr; 22(4):1157-64. View in: PubMed

. Longitudinal changes in insulin sensitivity and beta cell function between women with and without a history of gestational diabetes mellitus Diabetologia. 2013 Dec; 56(12):2753-60. View in: PubMed

. Prevention of diabetes with pioglitazone in ACT NOW: physiologic correlates Diabetes. 2013 Nov; 62(11):3920-6. View in: PubMed

. Prediction of diabetes based on baseline metabolic characteristics in individuals at high risk Diabetes Care. 2013 Nov; 36(11):3607-12. View in: PubMed

. High-fat diet is associated with obesity-mediated insulin resistance and ß-cell dysfunction in Mexican Americans J Nutr. 2013 Apr; 143(4):479-85. View in: PubMed

. Self-reported physical activity is associated with ß-cell function in Mexican American adults Diabetes Care. 2013 Mar; 36(3):638-44. View in: PubMed

. Pioglitazone slows progression of atherosclerosis in prediabetes independent of changes in cardiovascular risk factors Arterioscler Thromb Vasc Biol. 2013 Feb; 33(2):393-9. View in: PubMed

. The diagnosis of gestational diabetes mellitus: new paradigms or status quo? J Matern Fetal Neonatal Med. 2012 Dec; 25(12):2564-9. View in: PubMed

. Gestational diabetes mellitus: risks and management during and after pregnancy Nat Rev Endocrinol. 2012 Nov; 8(11):639-49. View in: PubMed

. Metabolic syndrome is linked to chromosome 7q21 and associated with genetic variants in CD36 and GNAT3 in Mexican Americans Obesity (Silver Spring). 2012 Oct; 20(10):2083-92. View in: PubMed

. Lysine-specific demethylase 1: an epigenetic regulator of salt-sensitive hypertension Am J Hypertens. 2012 Jul; 25(7):812-7. View in: PubMed

. A genome-wide association search for type 2 diabetes genes in African Americans PLoS One. 2012; 7(1):e29202. View in: PubMed

. Novel loci for adiponectin levels and their influence on type 2 diabetes and metabolic traits: a multi-ethnic meta-analysis of 45,891 individuals PLoS Genet. 2012; 8(3):e1002607. View in: PubMed

. Deterioration in cardiometabolic risk markers in obese women during depot medroxyprogesterone acetate use Contraception. 2012 Jan; 85(1):36-41. View in: PubMed

. Approach to the patient with gestational diabetes after delivery J Clin Endocrinol Metab. 2011 Dec; 96(12):3592-8. View in: PubMed

. Variants of the caveolin-1 gene: a translational investigation linking insulin resistance and hypertension J Clin Endocrinol Metab. 2011 Aug; 96(8):E1288-92. View in: PubMed

. The vicious cycle of maternal diabetes and obesity: moving from "what" to "how" and "why" J Pediatr. 2011 Jun; 158(6):872-3. View in: PubMed

. A better index of body adiposity Obesity (Silver Spring). 2011 May; 19(5):1083-9. View in: PubMed

. Pioglitazone for diabetes prevention in impaired glucose tolerance N Engl J Med. 2011 Mar 24; 364(12):1104-15. View in: PubMed

. Meta-analysis identifies 13 new loci associated with waist-hip ratio and reveals sexual dimorphism in the genetic basis of fat distribution Nat Genet. 2010 Nov; 42(11):949-60. View in: PubMed

. Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index Nat Genet. 2010 Nov; 42(11):937-48. View in: PubMed

. Limitations in surrogate measures of insulin resistance J Clin Endocrinol Metab. 2010 Nov; 95(11):4874-6. View in: PubMed

. Detailed physiological characterization of the development of type 2 diabetes in Hispanic women with prior gestational diabetes mellitus Diabetes. 2010 Oct; 59(10):2625-30. View in: PubMed

. Preventing type 2 diabetes with low-dose combinations Lancet. 2010 Jul 10; 376(9735):72-4. View in: PubMed

. Stemming the tide of type 2 diabetes: bring on the "big guns" Obesity (Silver Spring). 2010 Jun; 18(6):1065-7. View in: PubMed

. Obese adolescents show impaired meal responses of the appetite-regulating hormones ghrelin and PYY Obesity (Silver Spring). 2010 May; 18(5):918-25. View in: PubMed

. Diabetes: preventing type 2 diabetes mellitus: is metformin the answer? Nat Rev Endocrinol. 2010 May; 6(5):253-4. View in: PubMed

. Detailed physiologic characterization reveals diverse mechanisms for novel genetic Loci regulating glucose and insulin metabolism in humans Diabetes. 2010 May; 59(5):1266-75. View in: PubMed

. International association of diabetes and pregnancy study groups recommendations on the diagnosis and classification of hyperglycemia in pregnancy Diabetes Care. 2010 Mar; 33(3):676-82. View in: PubMed

. Declining beta-cell compensation for insulin resistance in Hispanic women with recent gestational diabetes mellitus: association with changes in weight, adiponectin, and C-reactive protein Diabetes Care. 2010 Feb; 33(2):396-401. View in: PubMed

. Genetic variation in GIPR influences the glucose and insulin responses to an oral glucose challenge Nat Genet. 2010 Feb; 42(2):142-8. View in: PubMed

. Additive effects of genetic variation in GCK and G6PC2 on insulin secretion and fasting glucose Diabetes. 2009 Dec; 58(12):2946-53. View in: PubMed

. Evidence for sex-specific associations between variation in acid phosphatase locus 1 (ACP1) and insulin sensitivity in Mexican-Americans J Clin Endocrinol Metab. 2009 Oct; 94(10):4094-102. View in: PubMed

. Replication of calpain-10 genetic association with carotid intima-media thickness Atherosclerosis. 2009 Aug; 205(2):503-5. View in: PubMed

. Actos Now for the prevention of diabetes (ACT NOW) study BMC Endocr Disord. 2009 Jul 29; 9:17. View in: PubMed

. Variation in IGF2BP2 interacts with adiposity to alter insulin sensitivity in Mexican Americans Obesity (Silver Spring). 2009 Apr; 17(4):729-36. View in: PubMed

. Variants in MTNR1B influence fasting glucose levels Nat Genet. 2009 Jan; 41(1):77-81. View in: PubMed

. Effect of pioglitazone on progression of subclinical atherosclerosis in non-diabetic premenopausal Hispanic women with prior gestational diabetes Atherosclerosis. 2008 Jul; 199(1):207-14. View in: PubMed

. Variations in the G6PC2/ABCB11 genomic region are associated with fasting glucose levels J Clin Invest. 2008 Jul; 118(7):2620-8. View in: PubMed

. Carotid intima-media thickness (cIMT) cosegregates with blood pressure and renal function in hypertensive Hispanic families Atherosclerosis. 2008 May; 198(1):160-5. View in: PubMed

. Association of insulin sensitivity and glucose tolerance with the c825C>T variant of the G protein beta-3 subunit gene. J Diabetes Complications. 2008 May-Jun; 22(3):205-9. View in: PubMed

. Evidence of interaction between PPARG2 and HNF4A contributing to variation in insulin sensitivity in Mexican Americans Diabetes. 2008 Apr; 57(4):1048-56. View in: PubMed

. A longitudinal study of lipids and blood pressure in relation to method of contraception in Latino women with prior gestational diabetes mellitus Diabetes Care. 2007 Aug; 30(8):1952-8. View in: PubMed

. Summary and recommendations of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus Diabetes Care. 2007 Jul; 30 Suppl 2:S251-60. View in: PubMed

. Genetics of gestational diabetes mellitus and type 2 diabetes Diabetes Care. 2007 Jul; 30 Suppl 2:S134-40. View in: PubMed

. What is gestational diabetes? Diabetes Care. 2007 Jul; 30 Suppl 2:S105-11. View in: PubMed

. (How) can we prevent type 2 diabetes? Diabetes. 2007 Jun; 56(6):1502-7. View in: PubMed

. A genome-wide association study of type 2 diabetes in Finns detects multiple susceptibility variants Science. 2007 Jun 01; 316(5829):1341-5. View in: PubMed

. Transcription factor 7-like 2 (TCF7L2) is associated with gestational diabetes mellitus and interacts with adiposity to alter insulin secretion in Mexican Americans Diabetes. 2007 May; 56(5):1481-5. View in: PubMed

. Effect of antihypertensive therapy on progression of carotid intima-media thickness in patients with type 2 diabetes mellitus Am J Cardiol. 2007 Apr 01; 99(7):956-60. View in: PubMed

. Screening of 134 single nucleotide polymorphisms (SNPs) previously associated with type 2 diabetes replicates association with 12 SNPs in nine genes Diabetes. 2007 Jan; 56(1):256-64. View in: PubMed

. Subsets of Finns with high HDL to total cholesterol ratio show evidence for linkage to type 2 diabetes on chromosome 6q Hum Hered. 2007; 63(1):17-25. View in: PubMed

. Common variants in maturity-onset diabetes of the young genes contribute to risk of type 2 diabetes in Finns Diabetes. 2006 Sep; 55(9):2534-40. View in: PubMed

. Effect of peroxisome proliferator-activated receptor gamma agonist treatment on subclinical atherosclerosis in patients with insulin-requiring type 2 diabetes Diabetes Care. 2006 Jul; 29(7):1545-53. View in: PubMed

. Effects of transdermal testosterone administration on insulin sensitivity, fat mass and distribution, and markers of inflammation and thrombolysis in human immunodeficiency virus-infected women with mild to moderate weight loss Fertil Steril. 2006 Jun; 85(6):1794-802. View in: PubMed

. Coordinate changes in plasma glucose and pancreatic beta-cell function in Latino women at high risk for type 2 diabetes Diabetes. 2006 Apr; 55(4):1074-9. View in: PubMed

. Long-acting injectable progestin contraception and risk of type 2 diabetes in Latino women with prior gestational diabetes mellitus Diabetes Care. 2006 Mar; 29(3):613-7. View in: PubMed

. Effect of pioglitazone on pancreatic beta-cell function and diabetes risk in Hispanic women with prior gestational diabetes Diabetes. 2006 Feb; 55(2):517-22. View in: PubMed

. Sequence variation in PPARG may underlie differential response to troglitazone Diabetes. 2005 Nov; 54(11):3319-25. View in: PubMed

. Mitochondrial polymorphisms and susceptibility to type 2 diabetes-related traits in Finns Hum Genet. 2005 Nov; 118(2):245-54. View in: PubMed

. Insulin resistance and preeclampsia in gestational diabetes mellitus Diabetes Care. 2005 Aug; 28(8):1995-2000. View in: PubMed

. Use of medications to prevent type 2 diabetes Curr Diab Rep. 2005 Aug; 5(4):237-9. View in: PubMed

. Effect of thiazolidinedione treatment on progression of subclinical atherosclerosis in premenopausal women at high risk for type 2 diabetes J Clin Endocrinol Metab. 2005 Apr; 90(4):1986-91. View in: PubMed

. Gestational diabetes mellitus J Clin Invest. 2005 Mar; 115(3):485-91. View in: PubMed

. Novel human alpha1a-adrenoceptor single nucleotide polymorphisms alter receptor pharmacology and biological function Naunyn Schmiedebergs Arch Pharmacol. 2005 Mar; 371(3):229-39. View in: PubMed

. Association between monocyte Fcgamma subclass expression and acute coronary syndrome Immun Ageing. 2004 Nov 12; 1(1):4. View in: PubMed

. Pharmacological treatment of insulin resistance at two different stages in the evolution of type 2 diabetes: impact on glucose tolerance and beta-cell function J Clin Endocrinol Metab. 2004 Jun; 89(6):2846-51. View in: PubMed

. Changes in insulin sensitivity in response to troglitazone do not differ between subjects with and without the common, functional Pro12Ala peroxisome proliferator-activated receptor-gamma2 gene variant: results from the Troglitazone in Prevention of Diabetes (TRIPOD) study Diabetes Care. 2004 Jun; 27(6):1365-8. View in: PubMed

. Frequency of EEG abnormalities in age-matched siblings of autistic children with abnormal sleep EEG patterns Epilepsy Behav. 2004 Apr; 5(2):159-62. View in: PubMed

. Complex distribution, not absolute amount of adiponectin, correlates with thiazolidinedione-mediated improvement in insulin sensitivity J Biol Chem. 2004 Mar 26; 279(13):12152-62. View in: PubMed

. A large set of Finnish affected sibling pair families with type 2 diabetes suggests susceptibility loci on chromosomes 6, 11, and 14 Diabetes. 2004 Mar; 53(3):821-9. View in: PubMed

. Changes in thrombolytic and inflammatory markers after initiation of indinavir- or amprenavir-based antiretroviral therapy Cardiovasc Toxicol. 2004; 4(2):179-86. View in: PubMed

. Time from diagnosis of type 2 diabetes to initiation of insulin therapy is related to carotid artery intima-media thickness Atherosclerosis. 2003 Oct; 170(2):293-9. View in: PubMed

. Fasting plasma glucose test at the first prenatal visit as a screen for gestational diabetes Obstet Gynecol. 2003 Jun; 101(6):1197-203. View in: PubMed

. C-reactive protein and glycemic control in adults with diabetes Diabetes Care. 2003 May; 26(5):1535-9. View in: PubMed

. Increased platelet Fc receptor expression as a potential contributing cause of platelet hypersensitivity to collagen in diabetes mellitus Br J Haematol. 2003 Apr; 121(1):139-42. View in: PubMed

. Prevention of type 2 diabetes: what is it really? Diabetes Care. 2003 Apr; 26(4):1306-8. View in: PubMed

. Counterpoint: glucose monitoring in gestational diabetes: lots of heat, not much light Diabetes Care. 2003 Mar; 26(3):948-9. View in: PubMed

. Pancreatic beta-cell loss and preservation in type 2 diabetes Clin Ther. 2003; 25 Suppl B:B32-46. View in: PubMed

. Preservation of pancreatic beta-cell function and prevention of type 2 diabetes by pharmacological treatment of insulin resistance in high-risk hispanic women Diabetes. 2002 Sep; 51(9):2796-803. View in: PubMed

. Prospective, intensive study of metabolic changes associated with 48 weeks of amprenavir-based antiretroviral therapy Clin Infect Dis. 2002 Aug 15; 35(4):475-81. View in: PubMed

. The ratio of plasminogen activator inhibitor type-1 activity to the concentration of plasminogen activator inhibitor type-1 protein in diabetes: adding insult to injury Coron Artery Dis. 2002 Aug; 13(5):275-81. View in: PubMed

. Variation in three single nucleotide polymorphisms in the calpain-10 gene not associated with type 2 diabetes in a large Finnish cohort Diabetes. 2002 May; 51(5):1644-8. View in: PubMed

. Heritability of subclinical atherosclerosis in Latino families ascertained through a hypertensive parent Arterioscler Thromb Vasc Biol. 2002 May 01; 22(5):843-8. View in: PubMed

. Clinical predictors for a high risk for the development of diabetes mellitus in the early puerperium in women with recent gestational diabetes mellitus Am J Obstet Gynecol. 2002 Apr; 186(4):751-6. View in: PubMed

. High-risk teen compliance with prescription contraception: an analysis of Ohio Medicaid claims J Pediatr Adolesc Gynecol. 2002 Feb; 15(1):15-21. View in: PubMed

. The effects of varying doses of T on insulin sensitivity, plasma lipids, apolipoproteins, and C-reactive protein in healthy young men J Clin Endocrinol Metab. 2002 Jan; 87(1):136-43. View in: PubMed

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