title: Association of early adult modifiable cardiovascular risk factors with left atrial size over a 20-year follow-up period: the CARDIA study.
abstract: OBJECTIVE
  We investigate how early adult and 20-year changes in modifiable cardiovascular risk factors (MRF) predict left atrial dimension (LAD) at age 43-55 years.
  
  
  METHODS
  The Coronary Artery Risk Development in Young Adults (CARDIA) study enrolled black and white adults (1985-1986). We included 2903 participants with echocardiography and MRF assessment in follow-up years 5 and 25. At years 5 and 25, LAD was assessed by M-mode echocardiography, then indexed to body surface area (BSA) or height. Blood pressure (BP), body mass index (BMI), heart rate (HR), smoking, alcohol use, diabetes and physical activity were defined as MRF. Associations of MRF with LAD were assessed using multivariable regression adjusted for age, ethnicity, gender and year-5 left atrial (LA) size.
  
  
  RESULTS
  The participants were 30±4 years; 55% white; 44% men. LAD and LAD/height were modest but significantly higher over the follow-up period, but LAD/BSA decreased slightly. Increased baseline and 20-year changes in BP were related to enlargement of LAD and indices. Higher baseline and changes in BMI were also related to higher LAD and LAD/height, but the opposite direction was found for LAD/BSA. Increase in baseline HR was related to lower LAD but not LAD indices, when only baseline covariates were included in the model. However, baseline and 20-year changes in HR were significantly associated to LA size.
  
  
  CONCLUSIONS
  In a biracial cohort of young adults, the most robust predictors for LA enlargement over a 20-year follow-up period were higher BP and BMI. However, an inverse direction was found for the relationship between BMI and LAD/BSA. HR showed an inverse relation to LA size.
authors.affiliation: Department of Cardiology, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Anderson C
authors.initials: AC
authors.lastname: Armstrong
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Gidding
authors.forename: Laura A
authors.initials: LA
authors.lastname: Colangelo
authors.forename: Satoru
authors.initials: S
authors.lastname: Kishi
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.forename: Stephen
authors.initials: S
authors.lastname: Sidney
authors.forename: Suma
authors.initials: S
authors.lastname: Konety
authors.forename: Cora E
authors.initials: CE
authors.lastname: Lewis
authors.forename: Luís C L
authors.initials: LC
authors.lastname: Correia
authors.forename: Joao A C
authors.initials: JA
authors.lastname: Lima
mesh_terms: D000328:Adult; D000367:Age Factors; D006332:Cardiomegaly / Q000209:etiology*; D002318:Cardiovascular Diseases / Q000150:complications*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D014463:Ultrasonography
keywords: Cardiology; Epidemiology