Epidemiology: Oxidative Stress and Early Atherosclerosis
Condition: Cardiovascular Diseases; Heart Diseases; Atherosclerosis; Coronary Arteriosclerosis
MeSH terms: Cardiovascular Diseases; Heart Diseases; Atherosclerosis; Arteriosclerosis; Coronary Artery Disease; Myocardial Ischemia
Study type: Observational

Summary: 
      To measure serum concentrations of alpha tocopherol, selenium and all major carotenoids
      (alpha- and beta- carotene, lutein, (beta-cryptoxanthin and lycopene) in Black and white,
      male and female, high and low education individuals aged 18-30 in 1985-86. In subsequent
      renewals additional markers of oxidative stress and endothelial dysfunction have been
      measured in blood collected 7 to 30 years after baseline.
    

Detailed description: 
      BACKGROUND:

      Low blood antioxidant concentrations are associated with several major degenerative diseases
      including cardiovascular disease and cancer. Animal, cellular and chemical experiments have
      elucidated biologic mechanisms consistent with antioxidant protection against several disease
      processes. Determinants of blood antioxidant concentrations are not well understood in young
      adults.

      The main scientific outcome of this research will be information on distribution and
      correlates of blood antioxidant concentrations, useful for formulating public health messages
      concerning maintenance of adequate levels of alpha tocopherol, selenium, ascorbic acid and
      the carotenoids.

      DESIGN NARRATIVE:

      An analysis was conducted using serum stored at 70 degrees Celsius, collected in 1985-86
      (n=5115) and 1992-93 (n=4086). These analytes were stable in serum samples collected, handled
      and stored under conditions used in this study. Integrity of the chemical analysis throughout
      the study was maintained by proven laboratory quality control procedures. Monitoring analyte
      concentrations in serum from collections seven years apart allowed analysis of age and time
      dependent changes in serum antioxidants. These data were linked with extensive pre-existing
      sociodemographic, dietary, other behavioral and physiologic data for the cohort. Statistical
      analyses provided information on the population's serum antioxidant distribution, tracking,
      change and major determinants in diverse young adults. In addition, these data established
      baseline and 7-year change concentration values for followup of this large CARDIA cohort,
      though the relationship of these serum antioxidants to disease endpoints was not itself part
      of the work scope. Study of plasma ascorbic acid, which is not stable under our storage
      conditions, was initiated using fresh samples to be collected in 1995-96 (n=4000).

      The Young Adult Longitudinal Study of Antioxidants (YALTA), ancillary to CARDIA study, was
      renewed in fiscal year 2000 to obtain additional blood and urine samples in the year 15 exam
      of the CARDIA participants. New measures of circulating lipid, protein, and DNA oxidation
      products (F2-isoprostanes, advanced glycosylation end-products [AGE], chlorinated and
      nitrosylated tyrosine, platelet aggregating factor (PAF) acetylhydrolase, paroxonase),
      urinary DNA damage, soluble intercellular adhesion molecule (ICAM), soluble P-selectin, and
      relevant genetic polymorphisms. The specific endpoints at the 15 year exam were coronary
      artery calcification as measured by computed tomography and microalbuminuria.

      The study was renewed in 2004 through 2008. Blood and urine was collected from subjects at
      the CARDIA year 20 exam to remeasure blood F2 isoprostanes, phospholipase A2, superoxide
      dismutase and carotenoids and tocopherols. Oxidized low density lipoprotein (LDL) and
      myeloperoxidase was also measured and analysis conducted of the association of antioxidant
      and oxidative damage levels and the development of subclinical macrovascular disease in this
      still-young group.

      The study renewed for a fourth time in 2010 through 2015, and a renewal application for a
      fifth renewal period was submitted in summer, 2014. It continues to write reports about
      different feature of oxidative stress and related phenomena as the CARDIA subjects age.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        The study sample was selected from residents of Minneapolis, MN, Birmingham, AL, Chicago,
        IL and Oakland, CA in 1985-86 as a community based sample.
      
Biospecimen description: 
      blood and urine samples and DNA