Mediators of the relationship between maternal education and children's TV viewing

BACKGROUND: Maternal education is consistently found to be inversely related to children's television viewing and is associated with aspects of the family television environment. This study investigates whether family television environment mediates the relationship between maternal education and children's television viewing. METHODS: Parents of 1484 children reported maternal education, time their child spends watching television, and 21 aspects of the family television environment (potential mediators) during 2002 and 2003. Separate regression analyses were conducted in 2006 for each potential mediator that met two initial conditions for mediation (associated with both maternal education and children's television viewing (p<0.10)), to assess whether inclusion reduced the association between maternal education and children's television viewing. Multivariable regression assessed the combined impact of all mediators. RESULTS: Twelve of 21 potential mediators met the initial conditions for mediation. Inclusion of each resulted in decreased beta values (3.2% to 15.2%) for the association between maternal education and television viewing. Number and placement of televisions in the home appeared to have the greatest mediating effect, followed by frequency of eating dinner in front of the television with the child and rules about television viewing during mealtimes. Together, the 12 mediators accounted for more than one-third of the association between maternal education and children's television viewing time. CONCLUSIONS: This study suggests the strong inverse relationship between maternal education and children's television viewing is partly mediated by aspects of the family television environment.     

A parent focused child obesity prevention intervention improves some mother obesity risk behaviors: the Melbourne infant program

ABSTRACT: BACKGROUND: The diets, physical activity and sedentary behavior levels of both children and adults in Australia are suboptimal. The family environment, as the first ecological niche of children, exerts an important influence on the onset of children's habits. Parent modeling is one part of this environment and a logical focus for child obesity prevention initiatives. The focus on parent's own behaviors provides a potential opportunity to decrease obesity risk behaviors in parents as well. OBJECTIVE: To assess the effect of a parent-focused early childhood obesity prevention intervention on first-time mothers' diets, physical activity and TV viewing time. METHODS: The Melbourne InFANT Program is a cluster-randomized controlled trial which involved 542 mothers over their newborn's first 18 months of life. The intervention focused on parenting skills and strategies, including parental modeling, and aimed to promote development of healthy child and parent behaviors from birth, including healthy diet, increased physical activity and reduced TV viewing time. Data regarding mothers' diet (food frequency questionnaire), physical activity and TV viewing times (self-reported questionnaire) were collected using validated tools at both baseline and post-intervention. Four dietary patterns were derived at baseline using principal components analyses including frequencies of 55 food groups. Analysis of covariance was used to measure the impact of the intervention. RESULTS: The scores of both the "High-energy snack and processed foods" and the "High-fat foods" dietary patterns decreased more in the intervention group: -0.22 ([MINUS SIGN]0.42;-0.02) and [MINUS SIGN]0.25 ([MINUS SIGN]0.50;-0.01), respectively. No other significant intervention vs. control effects were observed regarding total physical activity, TV viewing time, and the two other dietary patterns, i.e. "Fruits and vegetables" and "Cereals and sweet foods". CONCLUSIONS: These findings suggest that supporting first-time mothers to promote healthy lifestyle behaviors in their infants impacts maternal dietary intakes positively. Further research needs to assess ways in which we might further enhance those lifestyle behaviors not impacted by the InFANT intervention.     

Son preference and sex-selective abortion in China: informing policy options

Objectives

There is growing evidence in China that son preference is on the decline, but the sex ratio at birth is still the highest in the world at around 120 male births to 100 females. The aim of the study was to explore attitudes towards gender preference among people of reproductive age, to determine the reasons why the sex ratio is persistently high, and to inform policy options.

Methods

We conducted in-depth interviews with 212 individuals who aged from 18 to 39 in rural and urban areas of three provinces: Yunnan, Guizhou and Zhejiang.

Results

We show that while son preference has weakened considerably, it has not disappeared. The sex ratio remains high, because of this small minority of individuals, who still choose sex-selective abortion to ensure male offsprings.

Conclusions

Intensive local policy interventions have been successful in reducing the sex ratio in some areas and these should be disseminated widely. In addition, the law forbidding sex selection should be actively enforced, and the One Child Policy should be relaxed in some areas, to reduce the disproportionately high sex ratio in the second order births.     

Parents' dietary patterns are significantly correlated: findings from the Melbourne Infant Feeding Activity and Nutrition Trial Program

The objectives of the present study were to identify dietary patterns independently in first-time mothers and fathers, and to examine whether these patterns were correlated within families. Dietary intakes were collected at baseline in the Melbourne Infant Feeding Activity and Nutrition Trial Program using a validated FFQ in 454 pairs of first-time mothers and fathers. Education level was reported in associated questionnaires. Principal components analyses included frequencies of fifty-five food groups and were performed independently in mothers and fathers. Spearman's correlation coefficients were used to assess associations between dietary pattern scores. A total of four dietary patterns were identified in mothers and fathers. Of these, three dietary patterns had similar characteristics between these two populations, namely 'Fruits and vegetables', 'High-energy snack and processed foods', 'High-fat foods' in mothers; and 'Fruits', 'High-energy snack and processed foods', 'High-fat foods' in fathers. The following two additional patterns were identified: 'Cereals and sweet foods' in mothers and 'Potatoes and vegetables' in fathers. Patterns incorporating healthier food items were found to be positively associated with parent education. An inverse association with education was found for the 'High-fat foods' and 'High-energy snack and processed foods' dietary patterns. Qualitatively similar patterns between corresponding mothers and fathers were the most strongly correlated (ρ?=?0·34-0·45, P?相似文献   

Single nucleotide polymorphisms upstream from the β-carotene 15,15'-monoxygenase gene influence provitamin A conversion efficiency in female volunteers

β-Carotene, the most abundant provitamin A carotenoid in the diet, is converted to retinal by β-carotene 15,15'-monoxygenase (BCMO1). However, β-carotene absorption and conversion into retinal is extremely variable among individuals, with proportions of low responders to dietary β-carotene as high as 45%. Recently, 2 common nonsynonymous single nucleotide polymorphisms (SNPs) within the BCMO1 coding region (R267S; rs12934922 and A379V; rs7501331) revealed reduced catalytic activity, confirming that genetic variations contribute to the low responder phenotype. Because 4 SNPs 5' upstream from the BCMO1 gene were recently shown to affect circulating carotenoid concentrations, the current study aimed to investigate the effects of these SNPs on β-carotene conversion efficiency. Three of the 4 polymorphisms (rs6420424, rs11645428, and rs6564851) reduced the catalytic activity of BCMO1 in female volunteers by 59, 51, and 48%, respectively. The TG-rich lipoprotein fraction retinyl palmitate:β-carotene ratio was negatively correlated with the G allele of rs11645428 (r = -0.44; P = 0.018), whereas it was positively correlated with the G allele of rs6420424 (r = 0.53; P = 0.004) and the T allele of rs6564851 (r = 0.41; P = 0.028). Furthermore, large inter-ethnic variations in frequency of affected alleles were detected, with frequencies varying from 43 to 84% (rs6420424), 52 to 100% (rs11645428), and 19 to 67% (rs6564851). In summary, a range of SNPs can influence the effectiveness of using plant-based provitamin A carotenoids to increase vitamin A status in at-risk population groups and this effect may vary depending on ethnic origin.     

Global cost of correcting vision impairment from uncorrected refractive error

Objective

To estimate the global cost of establishing and operating the educational and refractive care facilities required to provide care to all individuals who currently have vision impairment resulting from uncorrected refractive error (URE).

Methods

The global cost of correcting URE was estimated using data on the population, the prevalence of URE and the number of existing refractive care practitioners in individual countries, the cost of establishing and operating educational programmes for practitioners and the cost of establishing and operating refractive care facilities. The assumptions made ensured that costs were not underestimated and an upper limit to the costs was derived using the most expensive extreme for each assumption.

Findings

There were an estimated 158 million cases of distance vision impairment and 544 million cases of near vision impairment caused by URE worldwide in 2007. Approximately 47 000 additional full-time functional clinical refractionists and 18 000 ophthalmic dispensers would be required to provide refractive care services for these individuals. The global cost of educating the additional personnel and of establishing, maintaining and operating the refractive care facilities needed was estimated to be around 20 000 million United States dollars (US$) and the upper-limit cost was US$ 28 000 million. The estimated loss in global gross domestic product due to distance vision impairment caused by URE was US$ 202 000 million annually.

Conclusion

The cost of establishing and operating the educational and refractive care facilities required to deal with vision impairment resulting from URE was a small proportion of the global loss in productivity associated with that vision impairment.     

Pathogenesis of varicose veins

Despite the high prevalence of varicose veins and the recent surge in research on the condition, the precise mechanisms underlying their development remain uncertain. In the past decade, there has been a shift from initial theories based on purely mechanical factors to hypotheses pointing to complex molecular changes causing histologic alterations in the vessel wall and extracellular matrix. Despite progress in understanding the molecular aspects of venous insufficiency, therapies for symptomatic varicose veins are directed toward anatomic and physical interventions. The present report reviews current evidence identifying the underlying biochemical alterations in the pathogenesis of varicose veins.