A developmental cascade perspective of paediatric obesity: a conceptual model and scoping review

Considering the immense challenge of preventing obesity, the time has come to reconceptualise the way we study the obesity development in childhood. The developmental cascade model offers a longitudinal framework to elucidate the way cumulative consequences and spreading effects of risk and protective factors, across and within biopsychosocial spheres and phases of development, can propel individuals towards obesity. In this article, we use a theory-driven model-building approach and a scoping review that included 310 published studies to propose a developmental cascade model of paediatric obesity. The proposed model provides a basis for testing hypothesised cascades with multiple intervening variables and complex longitudinal processes. Moreover, the model informs future research by resolving seemingly contradictory findings on pathways to obesity previously thought to be distinct (low self-esteem, consuming sugary foods, and poor sleep cause obesity) that are actually processes working together over time (low self-esteem causes consumption of sugary foods which disrupts sleep quality and contributes to obesity). The findings of such inquiries can aid in identifying the timing and specific targets of preventive interventions across and within developmental phases. The implications of such a cascade model of paediatric obesity for health psychology and developmental and prevention sciences are discussed.     

Longitudinal assessment of thrombin generation potential in response to alteration of antiplatelet therapy after TIA or ischaemic stroke

The impact of changing antiplatelet therapy on thrombin generation potential in patients with ischaemic cerebrovascular disease (CVD) is unclear. We assessed patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Thrombin generation was assessed in platelet poor plasma. Ninety-one patients were recruited. Twenty-four were initially assessed on no antiplatelet therapy, and then after 14d (N = 23) and 90d (N = 8) on aspirin monotherapy; 52 were assessed on aspirin monotherapy, and after 14 and 90 days on aspirin and dipyridamole combination therapy; 21 patients were assessed on aspirin and after 14 days (N = 21) and 90 days (N = 19) on clopidogrel. Peak thrombin generation and endogenous thrombin potential were reduced at 14 and 90 days (p ≤ 0.04) in the overall cohort. We assessed the impact of individual antiplatelet regimens on thrombin generation parameters to investigate the cause of this effect. Lag time and time-to-peak thrombin generation were unchanged at 14 days, but reduced 90 days after commencing aspirin (p ≤ 0.009). Lag time, peak thrombin generation and endogenous thrombin potential were reduced at both 14 and 90 days after adding dipyridamole to aspirin (p ≤ 0.01). Lag time was reduced 14 days after changing from aspirin to clopidogrel (p = 0.045), but this effect was not maintained at 90 days (p = 0.2). This pilot study did not show any consistent effects of commencing aspirin, or of changing from aspirin to clopidogrel on thrombin generation potential during follow-up. The addition of dipyridamole to aspirin led to a persistent reduction in peak and total thrombin generation ex vivo, and illustrates the diverse, potentially beneficial, newly recognised ‘anti-coagulant’ effects of dipyridamole in ischaemic CVD.     

Use of retail data in the assessment of natural experiments: the case of Reducing the Strength,an intervention to reduce alcohol availability

BackgroundRetailers routinely collect data about people's purchasing behaviours and access to consumer products associated with health and wellbeing. Here we discuss how retail data can be used in public health research and consider potential strengths and limitations to such research. To illustrate the discussion we refer to an evaluation of an intervention called Reducing the Strength, whereby off-licence shops and supermarkets voluntarily stopped selling inexpensive superstrength (≥6·5% alcohol by volume) beers and ciders.MethodsMonthly data from a large retail chain (East of England Co-operative Society) were obtained for three UK counties (141 stores). In one county the intervention started 12 months earlier than the others, allowing for a pre–post study design with a delayed implementation comparator. Difference-in-differences analysis of unit alcohol sales controlled for socioenvironmental confounders and shop-level characteristics including shop size, parking facilities, cash machines, opening hours, and other factors.FindingsThe retail data detailed shop-level characteristics and sales data such as prices, quantities, product brands, alcohol content, sales, and factors affecting sales. The wide geographical coverage, shop-level data, including data for potential confounding factors, and frequent timepoints made the retail data well-suited for a quasi-experimental evaluation capitalising on temporal and spatial variations in intervention exposure. Limitations of this study include a lack of longitudinal data for individual customers, and shops that are not covered by the data. Qualitative interviews with shop workers and customers, and triangulation using alternative data sources can help to address limitations. Alternative sources of retail data such as private sector consultants who specialise in collecting shop-level and sales data for a range of companies might also address some limitations; however, there are potential barriers of expense, accessibility, and coverage associated with the use of such consultants.InterpretationIncreasingly, researchers recognise the potential of retail data for evaluating interventions affecting social determinants of health and inequalities, such as local access to alcohol. However, shop-level data have frequently proved difficult for researchers to obtain. By obtaining such data we have been able to assess, using a quasi-experimental design, the effects of removing strong, cheap beers and ciders from shops. We have also been able to explore in more detail how to optimise the strengths and address some limitations of the data in ways that could potentially assist others planning to use this important data source in their research.FundingThe study is funded as part of the School of Public Health Research by NHS National Institute of Health Research. AJ, SA, and JW contributed as employees of Public Health Suffolk, Suffolk County Council.     

Access to written information for people with aphasia

Background : Accessibility is often constructed in terms of physical accessibility. There has been little research into how the environment can accommodate the communicative limitations of people with aphasia. Communication accessibility for people with aphasia is conceptualised in this paper within the World Health Organisation's International Classification of Functioning, Disability and Health (ICF). The focus of accessibility is considered in terms of the relationship between the environment and the person with the disability. Aims : This paper synthesises the results of three studies that examine the effectiveness of aphasia-friendly written material. Main Contribution : The first study (Rose, Worrall, & McKenna, 2003) found that aphasia-friendly formatting of written health information improves comprehension by people with aphasia, but not everyone prefers aphasia-friendly formatting. Brennan, Worrall, and McKenna (in press) found that the aphasia-friendly strategy of augmenting text with pictures, particularly ClipArt and Internet images, may be distracting rather than helpful. Finally, Egan, Worrall, and Oxenham (2004) found that the use of an aphasia-friendly written training manual was instrumental in assisting people with aphasia to learn the Internet. Conclusion : Aphasia-friendly formatting appears to improve the accessibility of written material for people with aphasia. Caution is needed when considering the use of illustrations, particularly ClipArt and Internet images, when creating aphasia-friendly materials. A research, practice, and policy agenda for introducing aphasia-friendly formatting is proposed.     

Human burst-forming units-erythroid need direct interaction with stem cell factor for further development

To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation.     

Maternal pre‐pregnancy body mass index is not associated with infant and young child feeding in low‐income Mexican children 1–24 months old

Pre‐pregnancy overweight and obesity is associated with shorter breastfeeding (BF) duration. Whether pre‐pregnancy overweight and obesity is associated with other aspects of infant and young child feeding (IYCF) has not been investigated. We used data from 370 children born January 1999–September 2001 in a semi‐urban community in Morelos, Mexico, where information on how they were fed was available at 1, 3, 6, 9, 12, 18 and 24 months of age. We modified the World Health Organization's dietary diversity indicator to assess the quality of the complementary foods. An index that included BF, quality of complementary foods and other behaviours was constructed to measure IYCF. We used survival analysis to examine the association of pre‐pregnancy body mass index (pBMI) category and BF duration and mixed models for quality of complementary food and IYCF index. Mean maternal pBMI was 24.4 ± 4.1; 31% were overweight, and 9% were obese. pBMI was not associated with BF duration. Quality of complementary food improved over time (6 months, 1.3 ± 1.3; 24 months, 3.8 ± 1.04). Compared with normal‐weight women, overweight and obese women were more likely to feed from more food groups (0.24 ± 0.11 point, P = 0.03), but this did not improve diet diversity from 6 to 24 months. IYCF index decreased throughout follow‐up (1 month, 7.8 ± 2.4; 24 months, 5.5 ± 1.8), and pBMI was not associated with IYCF (?0.11 ± 0.13 point, P = 0.4). We conclude that heavier women were not engaging in IYCF behaviours that were distinct from those of normal‐weight women from 1 to 24 months post‐partum.     

Low birth weights contribute to high rates of early-onset chronic renal failure in the Southeastern United States

BACKGROUND: The southeastern United States is a region in which rates of cardiovascular and renal diseases are excessive. Within the Southeast, South Carolina has unusually high rates of end-stage renal disease (ESRD) in young people, with more than 70% of cases attributed to hypertension and diabetes. OBJECTIVE: To determine whether the increased vulnerability to early-onset ESRD might originate through impaired renal development in utero as measured by low birth weight. METHODS: Patients who were diagnosed with renal failure and undergoing dialysis from 1991 through 1996 were identified from the ESRD registry maintained by the Southeastern Kidney Council, Raleigh, NC. Birth weights reported on birth certificates were selected for the ESRD cases and non-ESRD controls who were born in South Carolina in 1950 and later. Birth weights were compared for 1230 cases and 2460 controls who were matched for age, sex, and race. RESULTS: Low birth weight was associated with ESRD among men and women as well as blacks and whites. Among people whose birth weight was less than 2.5 kg, the odds ratio for ESRD was 1.4 (95% confidence interval, 1.1-1.8) compared with people who weighed 3 to 3.5 kg. This association was present for renal failure resulting from diabetes, hypertension, and other causes. CONCLUSIONS: Low birth weights, which reflect adverse effects on development in utero, contribute to the early onset of ESRD in South Carolina. Since low birth weight increases the risk of ESRD from multiple causes, the data suggest that an adverse environment in utero impairs kidney development and makes it more vulnerable to damage from a range of pathological processes.     

Dual endothelin‐1 receptor antagonism attenuates platelet‐mediated derangements of blood coagulation in Eisenmenger syndrome

Essentials

• Eisenmenger syndrome is characterised by thrombotic and hemorrhagic risks of unclear aetiology.
• Calibrated automated thrombography was used to assess these coagulation derangements.
• Platelet activity supported abnormalities in procoagulant and anticoagulant pathway function.
• Endothelin‐1 antagonism appeared to ameliorate these derangements.

Summary

Aims

The mechanisms underlying the competing thrombotic and hemorrhagic risks in Eisenmenger syndrome are poorly understood. We aimed to characterize derangements of blood coagulation and to assess the effect of dual endothelin‐1 receptor antagonism in modulating hemostasis in this rare disorder.

Methods

In a 10‐month recruitment period at a tertiary cardiology referral center, during which time there were over 14 000 outpatient consultations, consecutive subjects with Eisenmenger syndrome being considered for macitentan therapy (n = 9) and healthy volunteers (n = 9) were recruited. Plasma thrombin generation in platelet‐rich and platelet‐poor plasma was assessed by calibrated automated thrombography prior to and following therapy.

Results

Median peak plasma thrombin generation was higher in platelet‐rich plasma obtained from Eisenmenger syndrome subjects relative to controls (median peak thrombin [25th–75th percentile]: 228.3 [206.5–258.6] nm vs. 169.9 [164.3–215.8] nm ), suggesting a critical mechanistic role for platelets in supporting abnormal hypercoagulability in Eisenmenger syndrome. Abnormal enhanced sensitivity to the anticoagulant activity of activated protein C was also observed in platelet‐rich plasma in Eisenmenger syndrome, suggesting that derangements of platelet activity may influence the activity of anticoagulant pathways in a manner that might promote bleeding in this disease state. Following 6 months of macitentan therapy, attenuations in the derangements in both procoagulant and anticoagulant pathways were observed.

Conclusions

Abnormal platelet activity contributes to derangements in procoagulant and anticoagulant pathways in Eisenmenger syndrome. Therapies targeting the underlying vascular pathology appear to ameliorate these derangements and may represent a novel strategy for the management of the competing prothrombotic and hemorrhagic tendencies in this disorder.