title: Association of body mass index with arterial stiffness and blood pressure components: a twin study.
abstract: BACKGROUND
  Obesity, blood pressure and arterial stiffness are heritable traits interconnected to each other but their possible common genetic and environmental etiologies are unknown.
  
  
  METHODS
  We studied 228 monozygotic and 150 dizygotic twin pairs aged 18-82 years from Italy, Hungary and the United States, of which 45 monozygotic and 38 dizygotic pairs were discordant for body mass index (BMI; intrapair difference (Δ) in BMI ≥ 3 kg/m(2)). Blood pressure components and arterial stiffness were measured by TensioMed Arteriograph.
  
  
  RESULTS
  Hypertension was more prevalent among obese than non-obese individuals (55% vs. 29%, p < 0.001). Age-, sex- and country-adjusted heritability estimates were high for hemodynamic measures (45%-58%) and BMI (78%). According to bivariate Cholesky decomposition, phenotypic correlations between BMI and blood pressure components (r = -0.15 to 0.24, p < 0.05) were largely explained by additive genetic factors (65%-77%) with the remaining explained by the unique environment. When controlling for genetic factors within all monozygotic pairs, ΔBMI was significantly correlated with Δbrachial systolic blood pressure (SBP) and diastolic blood pressure (DBP), Δmean arterial pressure, and Δaortic SBP (r = 0.15-0.17, p < 0.05). For the same measures, heavier co-twins of BMI-discordant monozygotic pairs had significantly higher values than their leaner counterparts (p < 0.05).
  
  
  CONCLUSIONS
  Blood pressure components are moderately correlated with BMI, largely because of shared genetic factors. However, for the association of BMI with brachial SBP and DBP, aortic SBP and mean arterial pressure, acquired, modifiable factors were also found to be important.
authors.affiliation: Department of Radiology and Oncotherapy, Semmelweis University, 78/A Ulloi Street, 1082 Budapest, Hungary. tarnoki2@gmail.com
authors.forename: Adam Domonkos
authors.initials: AD
authors.lastname: Tarnoki
authors.forename: David Laszlo
authors.initials: DL
authors.lastname: Tarnoki
authors.forename: Leonie H
authors.initials: LH
authors.lastname: Bogl
authors.forename: Emanuela
authors.initials: E
authors.lastname: Medda
authors.forename: Corrado
authors.initials: C
authors.lastname: Fagnani
authors.forename: Lorenza
authors.initials: L
authors.lastname: Nisticò
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Stazi
authors.forename: Sonia
authors.initials: S
authors.lastname: Brescianini
authors.forename: Pierleone
authors.initials: P
authors.lastname: Lucatelli
authors.forename: Emanuele
authors.initials: E
authors.lastname: Boatta
authors.forename: Chiara
authors.initials: C
authors.lastname: Zini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Fanelli
authors.forename: Claudio
authors.initials: C
authors.lastname: Baracchini
authors.forename: Giorgio
authors.initials: G
authors.lastname: Meneghetti
authors.forename: Janos
authors.initials: J
authors.lastname: Osztovits
authors.forename: Gyorgy
authors.initials: G
authors.lastname: Jermendy
authors.forename: Robert Gabor
authors.initials: RG
authors.lastname: Kiss
authors.forename: Istvan
authors.initials: I
authors.lastname: Preda
authors.forename: Kinga
authors.initials: K
authors.lastname: Karlinger
authors.forename: Agnes
authors.initials: A
authors.lastname: Lannert
authors.forename: Andrea Agnes
authors.initials: AA
authors.lastname: Molnar
authors.forename: Levente
authors.initials: L
authors.lastname: Littvay
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Garami
authors.forename: Viktor
authors.initials: V
authors.lastname: Berczi
authors.forename: Giacomo
authors.initials: G
authors.lastname: Pucci
authors.forename: Gyorgy
authors.initials: G
authors.lastname: Baffy
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Schillaci
authors.forename: Kirsi H
authors.initials: KH
authors.lastname: Pietiläinen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000235:genetics; D001794:Blood Pressure / Q000235:genetics*; D015992:Body Mass Index; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000235:genetics*; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology / Q000235:genetics; D010641:Phenotype; D015995:Prevalence; D011673:Pulsatile Flow / Q000235:genetics; D012307:Risk Factors; D014429:Twins, Dizygotic / Q000235:genetics / Q000706:statistics & numerical data; D014430:Twins, Monozygotic / Q000235:genetics / Q000706:statistics & numerical data; D059289:Vascular Stiffness / Q000235:genetics*; D055815:Young Adult
keywords: Augmentation index; Central blood pressure; Hypertension; Obesity; Pulse wave velocity; Twin study