title: Association of plasma Aß peptides with blood pressure in the elderly.
abstract: BACKGROUND
  Aß peptides are often considered as catabolic by-products of the amyloid ß protein precursor (APP), with unknown physiological functions. However, several biological properties have been tentatively attributed to these peptides, including a role in vasomotion. We assess whether plasma Aß peptide levels might be associated with systolic and diastolic blood pressure values (SBP and DBP, respectively).
  
  
  RESULTS
  Plasma Aß(1-40) and Aß(1-42) levels were measured using an xMAP-based assay in 1,972 individuals (none of whom were taking antihypertensive drugs) from 3 independent studies: the French population-based 3C and MONA-LISA (Lille) studies (n = 627 and n = 769, respectively) and the Australian, longitudinal AIBL study (n = 576). In the combined sample, the Aß(1-42)/ Aß(1-40) ratio was significantly and inversely associated with SBP (p = 0.03) and a similar trend was observed for DBP (p = 0.06). Using the median age (69) as a cut-off, the Aß(1-42)/Aß(1-40) ratio was strongly associated with both SBP and DBP in elderly individuals (p = 0.002 and p = 0.03, respectively). Consistently, a high Aß(1-42)/ Aß(1-40) ratio was associated with a lower risk of hypertension in both the combined whole sample (odds ratio [OR], 0.71; 95% confidence interval [CI], 0.56-0.90) and (to an even greater extent) in the elderly subjects (OR, 0.53; 95% CI, 0.37-0.75). Lastly, all these associations appeared to be primarily driven by the level of plasma Aß(1-40).
  
  
  CONCLUSIONS
  The plasma Aß(1-42)/Aß(1-40) ratio is inversely associated with SBP, DBP and the risk of hypertension in elderly subjects, suggesting that Aß peptides affect blood pressure in vivo. These results may be particularly relevant in Alzheimer's disease, in which a high Aß(1-42)/Aß(1-40) plasma ratio is reportedly associated with a decreased risk of incident disease.
authors.affiliation: INSERM U744, Lille, France. jean-charles.lambert@pasteur-lille.fr
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Lambert
authors.forename: Jean
authors.initials: J
authors.lastname: Dallongeville
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Ellis
authors.forename: Susanna
authors.initials: S
authors.lastname: Schraen-Maschke
authors.forename: James
authors.initials: J
authors.lastname: Lui
authors.forename: Simon
authors.initials: S
authors.lastname: Laws
authors.forename: Julie
authors.initials: J
authors.lastname: Dumont
authors.forename: Florence
authors.initials: F
authors.lastname: Richard
authors.forename: Dominique
authors.initials: D
authors.lastname: Cottel
authors.forename: Claudine
authors.initials: C
authors.lastname: Berr
authors.forename: David
authors.initials: D
authors.lastname: Ames
authors.forename: Colin L
authors.initials: CL
authors.lastname: Masters
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Rowe
authors.forename: Cassandra
authors.initials: C
authors.lastname: Szoeke
authors.forename: Christophe
authors.initials: C
authors.lastname: Tzourio
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Dartigues
authors.forename: Luc
authors.initials: L
authors.lastname: Buée
authors.forename: Ralph
authors.initials: R
authors.lastname: Martins
authors.forename: Philippe
authors.initials: P
authors.lastname: Amouyel
mesh_terms: D000368:Aged; D016229:Amyloid beta-Peptides / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology*; D003710:Demography; D003971:Diastole / Q000502:physiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000503:physiopathology; D008297:Male; D013599:Systole / Q000502:physiology
chemical_list: D016229:Amyloid beta-Peptides