Cardiorespiratory fitness, exercise haemodynamics and birth outcomes: the Coronary Artery Risk Development in Young Adults Study.

OBJECTIVE: Determine associations of cardiorespiratory fitness, exercise systolic blood pressure (SBP) and heart rate recovery (HRR) following a maximal exercise test performed years preceding pregnancy with odds of preterm birth (PTB; <37 weeks' gestation) and small for gestational age (SGA; birthweight <10th percentile) delivery. DESIGN: Prospective, longitudinal. SETTING: Multi-site, observational cohort study initially consisting of 2787 black and white women aged 18-30 at baseline (1985-86) and followed for 25 years (Y25; 2010-2011). POPULATION: 768 nulliparous women at baseline who reported ≥1 live birth by the Y25 exam. METHODS: We used Poisson regression to determine associations of exposures with PTB/SGA. MAIN OUTCOME MEASURES: PTB and/or SGA births. RESULTS: Women with PTB (n = 143) and/or SGA (n = 88) were younger, had completed fewer years of education and were more likely to be black versus women without PTB/SGA (n = 546). Women with PTB/SGA had lower fitness (501 ± 9 versus 535 ± 6 seconds, P < 0.002) and higher submaximal SBP than women without PTB/SGA (144 ± 1 versus 142 ± 1 mmHg, P < 0.04). After adjustment, no exercise test variables were associated with PTB/SGA, though the association with HRR and submaximal SBP approached significance in the subset of women who completed the exercise test <5 years before the index birth. CONCLUSIONS: Neither fitness nor haemodynamic responses to exercise a median of 5 years preceding pregnancy, were associated with PTB/SGA. These findings indicate excess likelihood of PTB/SGA is not detectable by low fitness or exercise haemodynamic responses 5 years preceding pregnancy, but exercise testing, especially HRR and submaximal SBP, may be more useful when conducted closer to the onset of pregnancy. TWEETABLE ABSTRACT: Exercise testing conducted >5 years before pregnancy may not detect women likely to have PTB/SGA.

Higher pericardial adiposity is associated with prevalent diabetes: The Coronary Artery Risk Development in Young Adults study.

BACKGROUND AND AIMS: Pericardial adipose tissue (PAT) is located on both sides of the pericardium. We tested whether PAT was associated with prevalent diabetes at the year 25 exam of the Coronary Artery Risk Development in Young Adults (CARDIA) study. METHODS AND RESULTS: The CARDIA Year 25 exam (2010-2011) included complete data for all covariates on 3107 participants. Prevalent diabetes (n = 436) was defined as high fasting (≥126 mg/dl) or 2-h postload glucose (≥200 mg/dl) or HbA1c (≥6.5%) or use of diabetes medications. Volume of PAT was measured from computed tomographic scans. Logistic regression was performed to examine the relationship between quartiles of PAT and diabetes. In regression models adjusted for field center, sex, race, age, systolic blood pressure, total cholesterol, log triglycerides, and treatment with blood pressure and cholesterol lowering medication, PAT volume in the 4th quartile was significantly associated with diabetes status after adjustment for BMI (OR 2.57, 95% CI 1.66, 3.98) or visceral adipose tissue (OR 2.08, 95% CI 1.32, 3.29). PAT volume in the 2nd and 3rd quartiles was not significantly associated with diabetes status relative to the first quartile. CONCLUSIONS: Metabolically active pericardial adipose tissue is associated with prevalent diabetes only at higher volumes independent of overall obesity.

Self-reported and accelerometer-measured physical activity by body mass index in US Hispanic/Latino adults: HCHS/SOL.

The association between obesity and physical activity has not been widely examined in an ethnically diverse sample of Hispanic/Latino adults in the US. A cross-sectional analysis of 16,094 Hispanic/Latino adults 18-74 years was conducted from the multi-site Hispanic Community Health Study/Study of Latinos (HCHS/SOL). Body mass index (BMI) was measured and categorized into normal, overweight, and obese; underweight participants were excluded from analyses. Physical activity was measured using the 16-item Global Physical Activity Questionnaire and by an Actical accelerometer. Minutes/day of physical activity and prevalence of engaging in ≥ 150 moderate-vigorous physical activity (MVPA) minutes/week were estimated by BMI group and sex adjusting for covariates. No adjusted differences were observed in self-reported moderate (MPA), vigorous (VPA), or MVPA across BMI groups. Accelerometry-measured MPA, VPA, and MVPA were significantly higher for the normal weight (females: 18.9, 3.8, 22.6 min/day; males: 28.2, 6.1, 34.3 min/day, respectively) compared to the obese group (females: 15.3, 1.5, 16.8 min/day; males: 23.5, 3.6, 27.1 min/day, respectively). The prevalence of engaging in ≥ 150 MVPA minutes/week using accelerometers was lower compared to the self-reported measures. Efforts are needed to reach the Hispanic/Latino population to increase opportunities for an active lifestyle that could reduce obesity in this population at high risk for metabolic disorders.

A genotype risk score predicts type 2 diabetes from young adulthood: the CARDIA study.

AIMS/HYPOTHESIS: Genotype does not change over the life course and may thus facilitate earlier identification of individuals at high risk for type 2 diabetes. We hypothesised that a genotype score predicts incident type 2 diabetes from young adulthood and improves diabetes prediction models based on clinical risk factors alone. METHODS: The Coronary Artery Risk Development in Young Adults (CARDIA) study followed young adults (aged 18-30 years, mean age 25) serially into middle adulthood. We used Cox regression to build nested prediction models for incident type 2 diabetes based on clinical risk factors assessed in young adulthood (age, sex, race, parental history of diabetes, BMI, mean arterial pressure, fasting glucose, HDL-cholesterol and triacylglyercol), without and with a 38-variant genotype score. Models were compared with C statistics and continuous net reclassification improvement indices (NRI). RESULTS: Of 2,439 participants, 830 (34%) were black and 249 (10%) had a BMI ≥ 30 kg/m(2) at baseline. Over a mean 23.9 years of follow-up, 215 (8.8%) participants developed type 2 diabetes. The genotype score significantly predicted incident diabetes in all models, with an HR of 1.08 per risk allele (95% CI 1.04, 1.13) in the full model. The addition of the score to the full model modestly improved reclassification (continuous NRI 0.285; 95% CI 0.126, 0.433) but not discrimination (C statistics 0.824 and 0.829 in full models with and without score). Race-stratified analyses were similar. CONCLUSIONS/INTERPRETATION: Knowledge of genotype predicts type 2 diabetes over 25 years in white and black young adults but may not improve prediction over routine clinical measurements.

Adiposity measures and blood pressure in Chinese children and adolescents.

OBJECTIVE: To investigate the association of adiposity measures with blood pressure (BP) in Chinese children and adolescents. DESIGN: A cross-sectional study. PARTICIPANTS: 1330 boys and 1170 girls aged 6-18 years from a rural population-based cohort of twins studied in Anhui, China, 1998-2000. OUTCOME MEASURES: Adiposity measures included body mass index (BMI), total body fat and trunk fat assessed by dual-energy x-ray absorptiometry. BMI was divided into fat mass index (FMI) and lean mass index (LMI) in the analysis. Major outcomes included: systolic (S) and diastolic (D) BP. Both linear and logistic regressions were performed to assess gender-specific associations between various adiposity measures and BP, with adjustment for age and height. Generalised estimating equations were used to account for intra-twin pair correlations. RESULTS: Mean BMI and percentage body fat in children aged 6-11 years were 14.9 kg/m(2) and 9.7%, respectively; corresponding measures in children aged 12-18 years were 17.8 kg/m(2) and 14.2%. Adiposity measures were more strongly associated with SBP (p<0.05 in all age strata) than DBP (p<0.05 only in children aged 6-11 years). Both FMI (beta = 1.26-2.37) and LMI (beta = 1.00-1.71) are associated with SBP across age and gender strata after adjustment for age and height (p<0.05). CONCLUSIONS: These results indicate that, in this relatively lean population of Chinese children and adolescents, BP, particularly SBP, is positively associated with measures of adiposity. Of all the adiposity measures, BMI is the strongest predictor of BP.

Association of educational achievement with pulsatile arterial diameter change of the common carotid artery: the Atherosclerosis Risk in Communities (ARIC) Study, 1987-1992.

Education is strongly inversely associated with common carotid artery intima-media thickness in the Atherosclerosis Risk in Communities (ARIC) Study. The authors extended the ARIC study of preclinical atherosclerosis by evaluating the cross-sectional association of education with common carotid artery elasticity. This study included 10,091 Black and White men and women aged 45-64 years who were free of clinical coronary heart disease and stroke/transient ischemic attack. Arterial elasticity was assessed by pulsatile arterial diameter change (PADC), derived from phase-locked echo-tracking. The smaller the PADC, the stiffer the artery. Education was categorized into grade school, high school without graduation, high school with graduation, vocational school, some college, and graduate/professional school. PADC was directly associated with educational attainment. The mean PADCs, adjusted for age, height, diastolic diameter, systolic blood pressure, pulse pressure (linear and squared), ethnicity, gender, and smoking status, in successively higher education strata were 402 (standard error (SE) 5), 403 (SE 4), 407 (SE 3), 413 (SE 4), 416 (SE 2), and 417 (SE 4) microm (p = 0.007). To the authors' knowledge, this is the first time such an association has been reported. If arterial dilation impairment precedes arterial wall thickening in the atherosclerotic process, as recent studies on endothelial dysfunction suggest, these results indicate that low socioeconomic status may be associated with early arterial pathophysiologic changes-an effect that appears to be mediated by established cardiovascular disease risk factors.