Search

Purpose: This study aimed to establish whether time spent in sport-related physical activities and sedentary behaviors (e.g., TV viewing, videogame usage, and homework) was prospectively associated with change in blood pressure (BP) for 5 yr. Methods: Eight hundred and twenty-one students age 6 yr at baseline (397 girls and 424 boys) were examined from 2003-2004 to 2009-2011. Children completed detailed activity questionnaires. BP was measured using a standardized protocol. Results: After adjusting for age, ethnicity, parental education, parental history of hypertension, baseline height, BP, body mass index (BMI), baseline time spent in corresponding activity behavior, and change in BMI, each hour per day spent in total screen time was associated with a 0.69 and 0.59 mm Hg increase in diastolic BP (P = 0.01) and mean arterial BP (P = 0.01), respectively. In boys, each hour per day spent in TV viewing was associated with a concurrent 1.42-mm Hg increase in diastolic BP (P = 0.04) during the 5 yr. Children engaging in low sport-related physical activities at baseline but who engaged in high levels of physical activity (≥60 min• d -1) at follow-up (n = 154) compared with those engaging in low sport-related physical activities at both examinations (n = 305) demonstrated significantly lower mean arterial BP, 7.26 versus 9.61 mm Hg (P = 0.04). Conclusions: Time spent in physical activity and screen time could influence BP measures during childhood. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to investigate the association between birth parameters (weight, length, and head circumference) and time spent in physical activity (outdoor and indoor) and screen time (TV viewing, computer, and video game usage) among adolescents. Using a longitudinal cohort study researchers evaluated 1,794 children in 2004-2005 and 2009-2010. After adjusting their research according to several variables, researchers concluded that birth weight could be a potential determinant of physical activity but not of screen time during adolescence.

The article offers information on a study that explored the link between the glycemic index and glycemic load of foods and the dietary intakes of carbohydrates, sugars, fiber, and principal carbohydrate-containing food groups with changes in blood pressure during adolescence. The study assessed data from validated semiquantitative food frequency questionnaires. It covered a total of 858 students aged 12 years at baseline.

We aimed to assess the associations between parental history of hypertension and indicators of cardiovascular risk (retinal vessel diameter, presence of obesity, and elevated blood pressure) in prepubertal children. There were 1739 (77.7% of those eligible) 6-year-old students (863 girls and 876 boys) who were examined from a random cluster sample of 34 Sydney schools. Parents completed questionnaires about their medical conditions, including whether they have/had hypertension. Retinal images were taken with a digital fundus camera, and retinal vessel caliber was quantified using computer software. Anthropometric (height, weight, percentage of body fat, and body mass index) and blood pressure measures were collected. There were 160 children (9.2%) with a positive parental history of hypertension (either biological mother and/or father). Children with a positive versus negative parental history of hypertension had significantly higher body mass index (16.8 versus 16.5 kg/m(2); P=0.04) and systolic blood pressure (101.3 versus 99.8 mm Hg; P=0.01). Girls with positive versus negative parental history of hypertension had significantly higher diastolic blood pressure (≈3.1 mm Hg; P=0.01) and narrower retinal arteriolar caliber (≈4.3 μm; P=0.0004). Positive parental history of hypertension was not associated with mean retinal vascular caliber among boys. We show that a positive parental history of hypertension in healthy prepubertal girls, but not boys, is associated with narrower retinal arteriolar vessels, likely conveying a predisposition to develop hypertension later in life. These findings may indicate the need for cardiovascular disease prevention measures starting early in life among offspring of hypertensive parents. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the epidemiology of Gunn's dots and their associations in a population-based cohort of children., Methods: Red-free fundus photographs from 2,286 children aged 11 years to 14 years from the Sydney Myopia Study were graded. Gunn's dots were manually marked and counted within a 6 mm grid centered on the optic disc., Results: One or more Gunn's dots were seen in at least one eye in 82.6% of children. The median number of Gunn's dots per eye was 46 (range 0-482). Most Gunn's dots were found inferior and superior of the optic disc (49.3% and 45.8%, respectively, of the total number of Gunn's dots in the population). The odds for having 1 or more Gunn's dots were 3-fold greater in children with dark brown irides compared with children with blue irides (odds ratio 2.99, 95% CI 1.81 to 4.94, P < 0.0001 adjusted for age, sex, retinal nerve fiber layer thickness, refraction, ethnicity, and axial length). In the same analysis, the presence of 1 or more Gunn's dots was less frequent in children with thin retinal nerve fiber layers (first quartile) compared with children with thick retinal nerve fiber layers (fourth quartile) (odds ratio 0.68, 95% CI 0.49-0.93, P = 0.016). No disease or disease-marker associations were identified., Conclusion: Gunn's dots were visible on fundus photographs in most of the school children, most of the dots being located inferiorly and superiorly to the optic disc. Fundus photographically visible Gunn's dots were associated with darker irides and thicker retinal nerve fiber layers. Gunn's dots are a common and apparently harmless finding in children. Assessment of their clinical significance will require long-term follow-up.

Objective: It is not clear whether physical activity and sedentary behavior affect retinal microvascular caliber. We investigated associations among physical activity (outdoor and indoor sporting activities), sedentary behaviors (including screen time, television [TV] viewing, and computer and videogame usage), and retinal microvascular caliber in schoolchildren., Methods and Results: Six-year-old students (1765/2238) from a random cluster sample of 34 Sydney schools were examined. Parents completed questionnaires about physical and sedentary activities. Retinal images were taken, and retinal vessel caliber was quantified. After adjusting for age, sex, ethnicity, eye color, axial length, body mass index, birth weight, and mean arterial blood pressure, children who spent more time in outdoor sporting activities (in the highest tertile of activity) had 2.2 μm (95% CI 0.65 to 3.71) wider mean retinal arteriolar caliber than those in the lowest tertile (Ptrend=0.004). Increasing quartiles of time spent watching TV were associated with narrower mean retinal arteriolar caliber≈2.3 μm (95% CI 0.73 to 3.92), Ptrend=0.003., Conclusions: These data suggest that physical activity could have a beneficial influence, whereas screen time has a potential adverse influence on retinal microvascular structure. The magnitude of arteriolar narrowing associated with each hour daily of TV viewing is similar to that associated with a 10-mm Hg increase in systolic blood pressure in children.

Unlabelled: Gender can influence many cardiovascular events, including cardiac hypertrophy. The presence of and dynamic changes involving androgen receptor (AR) gene expression are important confirmatory findings for androgen modulation in the pathogenesis of cardiac hypertrophy., Aims: To determine AR expression profile during neonatal hypertrophy and its regression process using a rat model., Methods: Relative mRNA levels of the AR gene were quantified at postnatal days 1, 7, 14, 21 and 28 using real time PCR., Results: A significant 10.6-fold decrease in AR transcription levels was observed at birth in neonates with cardiac hypertrophy (p < 0.05). Our analysis also showed a significant increase in AR mRNA levels at day 28, corresponding with regression of cardiac hypertrophy., Discussion: The AR gene demonstrated a noteworthy trend in its expression pattern. The initial down-regulation was most likely the result of increased testosterone levels induced by hyperinsulinaemia and hypoglycaemia, which were present in neonates from diabetic mothers during pregnancy. The paradoxical increase in AR at day 28 suggested a potential long term-effect of the in utero diabetic environment.