title: Relationship of a dominant advanced glycation end product, serum carboxymethyl-lysine, and abnormal glucose metabolism in adults: the Baltimore Longitudinal Study of Aging.
abstract: OBJECTIVE
  Although hyperglycemia is thought to increase the generation of advanced glycation end products (AGEs), studies have not shown a consistent relationship between abnormal glucose metabolism and serum AGEs. We investigated the relationship between a dominant serum AGE, N-carboxymethyl-lysine (CML), and glucose metabolism.
  
  
  METHODS
  Serum CML, fasting plasma glucose, and glucose tolerance were measured in 755 adults in the Baltimore Longitudinal Study of Aging. Fasting plasma glucose was categorized as normal (< or = 99 mg/dL), impaired (100-125 mg/dL), and diabetic (> 125 mg/dL). Two-hour plasma glucose on oral glucose tolerance testing was categorized as normal (< or = 139 mg/dL), impaired (140-199 mg/dL), and diabetic (> or = 200 mg/dL).
  
  
  RESULTS
  The proportion of adults with normal, impaired, and diabetic fasting plasma glucose was 73.8%, 22.9%, and 2.9%, respectively, and the proportion with normal, impaired, and diabetic 2-hour plasma glucose was 73.1%, 19.2%, and 7.7%, respectively. Serum CML (microg/mL) was not associated with abnormal fasting plasma glucose (Odds Ratio [O.R.] 0.60, 95% Confidence Interval [C.I.] 0.15-2.36, P = 0.47) in a multivariate, ordered logistic regression model, adjusting for age, race, gender, body mass index, and chronic diseases. Serum CML (microg/mL) was associated with abnormal 2-hour plasma glucose on glucose tolerance testing (O.R. 0.15, 95% C.I. 0.04-0.63, P = 0.009) in a multivariate, ordered logistic regression model, adjusting for the same covariates.
  
  
  CONCLUSIONS
  Elevated CML, a dominant AGE, was not associated with elevated fasting plasma glucose and was associated with a reduced odds of abnormal glucose tolerance in older community-dwelling adults.
authors.affiliation: Johns Hopkins School of Medicine, Baltimore, MD 21287, USA. rdsemba@jhmi.edu
authors.forename: R D
authors.initials: RD
authors.lastname: Semba
authors.forename: J
authors.initials: J
authors.lastname: Beck
authors.forename: K
authors.initials: K
authors.lastname: Sun
authors.forename: J M
authors.initials: JM
authors.lastname: Egan
authors.forename: O D
authors.initials: OD
authors.lastname: Carlson
authors.forename: R
authors.initials: R
authors.lastname: Varadhan
authors.forename: L
authors.initials: L
authors.lastname: Ferrucci
mesh_terms: D000368:Aged; D015142:Baltimore; D001786:Blood Glucose / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000097:blood; D005260:Female; D018149:Glucose Intolerance / Q000097:blood*; D005951:Glucose Tolerance Test; D017127:Glycation End Products, Advanced / Q000097:blood*; D006801:Humans; D016015:Logistic Models; D008239:Lysine / Q000031:analogs & derivatives* / Q000097:blood; D008297:Male; D008875:Middle Aged
chemical_list: D001786:Blood Glucose; D017127:Glycation End Products, Advanced; C048496:N(6)-carboxymethyllysine; D008239:Lysine
references.citation: Am J Clin Nutr. 2007 May;85(5):1236-43
references.pmid: 17490958
references.citation: Biochim Biophys Acta. 2004 Mar 22;1636(2-3):82-9
references.pmid: 15164755
references.citation: Clin Chem Lab Med. 2005;43(5):503-11
references.pmid: 15899672
references.citation: Diabetes Care. 1999 Sep;22(9):1543-8
references.pmid: 10480523
references.citation: Diabetes Obes Metab. 2005 May;7(3):263-7
references.pmid: 15811143
references.citation: Eur J Nutr. 2009 Feb;48(1):38-44
references.pmid: 19031098
references.citation: Curr Diab Rep. 2007 Jun;7(3):235-41
references.pmid: 17547841
references.citation: Biochemistry. 1995 Aug 29;34(34):10872-8
references.pmid: 7662668
references.citation: Diabetes Care. 2003 Jan;26 Suppl 1:S5-20
references.pmid: 12502614
references.citation: JAMA. 2001 May 16;285(19):2486-97
references.pmid: 11368702
references.citation: Neth J Med. 2006 Jan;64(1):10-6
references.pmid: 16421436
references.citation: Diabetes Care. 1998 Nov;21(11):1997-2002
references.pmid: 9802757
references.citation: Diabet Med. 2003 Jul;20(7):575-9
references.pmid: 12823240
references.citation: Ann Intern Med. 1999 Mar 16;130(6):461-70
references.pmid: 10075613
references.citation: Diabetologia. 2004 Aug;47(8):1376-9
references.pmid: 15258735
references.citation: Am J Kidney Dis. 2003 Sep;42(3):532-8
references.pmid: 12955681
references.citation: Cardiovasc Res. 2004 Sep 1;63(4):582-92
references.pmid: 15306213
references.citation: J Am Diet Assoc. 2004 Aug;104(8):1287-91
references.pmid: 15281050
references.citation: Am J Kidney Dis. 2006 Oct;48(4):571-9
references.pmid: 16997053
references.citation: Clin Chem. 1972 Jun;18(6):499-502
references.pmid: 4337382
references.citation: J Diabetes Complications. 2003 Jan-Feb;17(1):16-21
references.pmid: 12505751
references.citation: Diabetes Care. 2002 Jun;25(6):1055-9
references.pmid: 12032114
references.citation: Diabetes Res Clin Pract. 1998 Aug;41(2):131-7
references.pmid: 9789719
references.citation: J Gerontol A Biol Sci Med Sci. 2007 Apr;62(4):427-33
references.pmid: 17452738
references.citation: Endocr J. 2004 Dec;51(6):537-44
references.pmid: 15644571
references.citation: Obes Res. 2001 Nov;9 Suppl 4:228S-233S
references.pmid: 11707546
references.citation: Clin Chem. 1982 Jun;28(6):1379-88
references.pmid: 7074948
references.citation: Proc Natl Acad Sci U S A. 1997 Jun 10;94(12):6474-9
references.pmid: 9177242
references.citation: Am J Physiol Renal Physiol. 2005 Oct;289(4):F645-59
references.pmid: 16159899
references.citation: J Am Geriatr Soc. 2009 Oct;57(10):1874-80
references.pmid: 19682127