[Show abstract][Hide abstract] ABSTRACT: Exposure to ambient air pollutants increases risk for cardiovascular health outcomes in adults. The contribution of childhood air pollutant exposure to cardiovascular health has not been thoroughly evaluated.
The Testing Responses on Youth study consists of 861 college students recruited from the University of Southern California in 2007 to 2009. Participants attended 1 study visit during which blood pressure, heart rate, and carotid artery intima-media thickness (CIMT) were assessed. Self-administered questionnaires collected information about health and sociodemographic characteristics, and a 12-hour fasting blood sample was drawn for lipid and biomarker analyses. Residential addresses were geocoded and used to assign cumulative air pollutant exposure estimates based on data derived from the U.S. Environmental Protection Agency's Air Quality System database. The associations between CIMT and air pollutants were assessed using linear regression analysis. Mean CIMT was 603 μm (±54 SD). A 2 standard deviation (SD) increase in childhood (aged 0-5 years) or elementary school (aged 6-12 years) O(3) exposure was associated with a 7.8-μm (95% confidence interval, -0.3-15.9) or 10.1-μm (95% confidence interval, 1.8-18.5) higher CIMT, respectively. Lifetime exposure to O(3) showed similar but nonsignificant associations. No associations were observed for PM(2.5), PM(10), or NO(2), although adjustment for these pollutants strengthened the childhood O(3) associations.
Childhood exposure to O(3) may be a novel risk factor for CIMT in a healthy population of college students. Regulation of air pollutants and efforts that focus on limiting childhood exposures continue to be important public health goals.
[Show abstract][Hide abstract] ABSTRACT: Racial/ethnic differences in common carotid artery intima-media thickness (CIMT) and in risk factors associated with CIMT have been predominantly observed in middle-aged and older individuals. We aimed to characterize racial/ethnic differences CIMT and other cardiovascular risk factors in a healthy, young-adult population.
College students were recruited as part of a study to characterize determinants of atherogenesis. Students were eligible if they were lifetime non-smokers, lived in the United States since six months of age, and attended high school in the United States. Blood pressure, heart rate, height, and weight were measured, B-mode carotid ultrasound was performed, questionnaires were administered and a 12-h fasting blood sample was collected. Associations between CIMT and other variables were assessed in 768 students aged 18-25 years using linear regression analysis.
In models adjusted for common cardiovascular risk factors, sex exhibited the strongest influence on CIMT, with men having 15.4 μm larger CIMT compared to women (95%CI 6.6, 24.2). Race/ethnicity was also strongly associated with CIMT. African Americans had 17.3 μm greater CIMT (95%CI -0.3, 34.8) compared to non Hispanic Whites, whereas Asians and Hispanic Whites had 14.3 (95%CI -24.3, -4.4) and 15.4 (95%CI -26.2, -4.7) μm smaller CIMT, respectively. BMI and systolic blood pressure were positively associated with CIMT.
The risk factors associated with atherogenesis later in life are already present and observable in college-aged young adults, so targeted campaigns to reduce life-long cardiovascular disease burden should be initiated earlier in life to improve public health.
[Show abstract][Hide abstract] ABSTRACT: Raloxifene, a selective estrogen receptor modulator (SERM), decreases total and low-density lipoprotein cholesterol (LDL-C) in postmenopausal women and inhibits increases in intima-media thickness (IMT) in animal models. We tested whether up to 8 years exposure to raloxifene had an effect on subclinical atherosclerosis in the 4-year Multiple Outcomes of Raloxifene Evaluation (MORE) trial and the follow-up study, the 4-year Continuing Outcomes Relevant to Evista (CORE) trial.
A subsample of postmenopausal women with osteoporosis, who had completed the MORE and CORE trials and were on average 68 years of age and 19 years postmenopausal at randomization into MORE, participated in this substudy. Within 6 months of cessation of study drug in CORE, right common carotid artery IMT (CIMT) and carotid artery stiffness and arterial compliance were measured at one of two sites (San Diego and San Francisco) using high-resolution B-mode ultrasound. CIMT and arterial stiffness measures were compared between women who had received raloxifene vs. placebo; the primary analysis included only women who were >or=80% drug compliant and had used <or=6 months of lipid-lowering medication during CORE.
For the primary analysis dataset (n = 89), there was no significant difference in mean CIMT between the raloxifene and placebo groups (0.83 and 0.81 mm, respectively, p = 0.62). Carotid artery stiffness and compliance were not significantly different between treatment groups (p = 0.33 and 0.59, respectively).
These preliminary data suggest that in this self-selected group of elderly post-menopausal women with osteoporosis who were evaluated within 6 months of cessation of study medication, there were no differences between long-term raloxifene treatment and placebo groups in several measures of subclinical atherosclerosis.
Journal of Women's Health 04/2007; 16(3):370-8. · 1.90 Impact Factor