title: Segment-specific association between plasma homocysteine level and carotid artery intima-media thickness in the Framingham Offspring Study.
abstract: Elevated plasma total homocysteine (tHcy) level is an established risk factor for cardiovascular disease. The relationship between tHcy and carotid artery intima-media thickness (IMT) at the internal carotid artery (ICA)/bulb-IMT and common carotid artery (CCA)-IMT had not been systematically studied, however. Because the ICA/bulb segment is more prone to plaque formation than the CCA segment, differential associations with tHcy at these sites might suggest mechanisms of tHcy action. We examined the cross-sectional segment-specific relationships of tHcy to ICA/bulb-IMT and CCA-IMT in 2499 participants from the Framingham Offspring Study who were free of cardiovascular disease. In multivariate linear regression analysis, ICA/bulb-IMT was significantly higher in the fourth tHcy quartile category compared with the other quartile categories, in both the age- and sex-adjusted and the multivariate-adjusted models (P for trend <.0001 and <.01, respectively). We observed a significant age-by-tHcy interaction for ICA/bulb-IMT (P=.03) and thus stratified the analyses by median age (58 years). A significant positive trend between tHcy and ICA/bulb-IMT was seen in individuals age ≥58 years (P for trend <.01), but not in younger individuals (P for trend=.24) in multivariate-adjusted models. For CCA-IMT, no significant trends were observed in any of the analyses. The segment-specific association between elevated tHcy level and ICA/bulb-IMT suggests an association between tHcy and plaque formation.
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA. mariondietric@msn.com
authors.forename: Marion
authors.initials: M
authors.lastname: Dietrich
authors.forename: Paul F
authors.initials: PF
authors.lastname: Jacques
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Polak
authors.forename: Michelle J
authors.initials: MJ
authors.lastname: Keyes
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pencina
authors.forename: Jane C
authors.initials: JC
authors.lastname: Evans
authors.forename: Philip A
authors.initials: PA
authors.lastname: Wolf
authors.forename: Jacob
authors.initials: J
authors.lastname: Selhub
authors.forename: Ramachandran S
authors.initials: RS
authors.lastname: Vasan
authors.forename: Ralph B
authors.initials: RB
authors.lastname: D'Agostino
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000097:blood* / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D018570:Risk Assessment; D012307:Risk Factors; D017539:Tunica Intima / Q000000981:diagnostic imaging*; D017540:Tunica Media / Q000000981:diagnostic imaging*; D014463:Ultrasonography; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D006710:Homocysteine