Associations of Maternal Educational Level, Proximity to Green Space During Pregnancy, and Gestational Diabetes With Body Mass Index From Infancy to Early Adulthood: A Proof-of-Concept Federated Analysis in 18 Birth Cohorts

International sharing of cohort data for research is important and challenging. We explored the feasibility of multicohort federated analyses by examining associations between 3 pregnancy exposures (maternal education, exposure to green vegetation, and gestational diabetes) and offspring body mass index (BMI) from infancy to age 17 years. We used data from 18 cohorts (n = 206,180 mother-child pairs) from the EU Child Cohort Network and derived BMI at ages 0-1, 2-3, 4-7, 8-13, and 14-17 years. Associations were estimated using linear regression via 1-stage individual participant data meta-analysis using DataSHIELD. Associations between lower maternal education and higher child BMI emerged from age 4 and increased with age (difference in BMI z score comparing low with high education, at age 2-3 years = 0.03 (95% confidence interval (CI): 0.00, 0.05), at 4-7 years = 0.16 (95% CI: 0.14, 0.17), and at 8-13 years = 0.24 (95% CI: 0.22, 0.26)). Gestational diabetes was positively associated with BMI from age 8 years (BMI z score difference = 0.18, 95% CI: 0.12, 0.25) but not at younger ages; however, associations attenuated towards the null when restricted to cohorts that measured gestational diabetes via universal screening. Exposure to green vegetation was weakly associated with higher BMI up to age 1 year but not at older ages. Opportunities of cross-cohort federated analyses are discussed.

Medical demography at stroke centers: Current situation in France

INTRODUCTION

Following the 2010-2014 French national stroke action plan, the number of stroke center (SC) has gradually increased in France, allowing a homogeneous coverage and access to neurovascular care in organized and territorially defined structures. However, operational difficulties within SCs have been progressively reported over the last few years. The objective of this study was to identify the medical staff shortages in SC that may contribute to these difficulties.

METHODS

A survey on the medical staffing level as of January 1, 2021 was sent to all French SC managers. Specific questions related on vacancies, need of interim medical staff, and participation in out-of-hour healthcare services.

RESULTS

Among the 139 SC managers contacted, 122 (88%) filled in the questionnaire. Analysis of the data showed that over 879 physician positions opened, 163 (18.5%) remained vacant for a mean of two years, and that in 51 SCs (41.9%), more than two positions were unfilled. In 13 of these 51 SCs, the out-of-hour healthcare services relied on less than four practitioners, defining a critical situation, and three other SCs had to close temporarily (2) or permanently (1). Moreover, 39.2% of SCs with at least one vacancy used interim physicians, for a median period of 12.5 weeks/year (IQR 5-18).

CONCLUSION

This study highlights the significant medical staff shortage in French SCs. In the absence of urgent measures, more SCs will close, jeopardizing the regional network and access to care for stroke patients.

Women Consumers' Views on Legislation to Restrict Prominent Placement and Multibuy Promotions of High Fat, Sugar, and Salt Products in England: A Qualitative Perspective

BACKGROUND

As part of the childhood obesity strategy, the UK Government has introduced regulations to restrict the ways high fat salt and sugar (HFSS) products can be promoted in retail settings from October 2022. This study explored (i) consumers' views on the likely impact of the UK legislation restricting the placement and promotion of HFSS products on their shopping behaviours and (ii) consumers' beliefs about who is responsible for healthy eating.

METHODS

Using a cross-sectional study design, qualitative semi-structured telephone interviews were conducted with a purposive sample of women who shopped at a discount supermarket. Thematic analysis was employed to identify key themes.

RESULTS

Participants' (n = 34) had a median age of 35 years and over half were in paid employment. Five themes were identified: (1) The legislation is acceptable, but people can still (and should be able to) buy HFSS items; (2) The legislation is likely to have more impact on shoppers who do not plan their shopping; (3) Affordability of healthy food is just as, or more, important than the legislation; (4) It's up to the individual to eat healthily; and (5) Government and retailers can better support consumers to make healthy choices.

CONCLUSION

Most participants were optimistic about the incoming regulations and believed that it would support consumers to make healthier food choices. Many raised concerns, however, that the high price of healthy foods and continued availability of unhealthy foods within the stores could undermine the legislation's benefits. Coupling the legislation with interventions to promote and reduce the costs of healthier products would go some way to ensure its success. Raising awareness about marketing strategies that play into consumer concerns for cost and autonomy could further increase acceptance of the policy.

The interplay between social and food environments on UK adolescents' food choices: implications for policy

Factors from social and food environments can influence the food choices of adolescents in ways not experienced during childhood. Evidence suggests these two environments influence adolescents' food choices independently, but there is limited knowledge of how the interplay between these environments influence adolescents' diets. An enhanced understanding of this interplay surrounding adolescent food choice could aid the development of more nuanced interventions and policies. This qualitative study involved 13 online focus groups with adolescents (n = 45) aged 11-18 years, attending secondary school or college in England, UK. Data were analysed using thematic analysis. Social experiences which accompanied eating were perceived as more important than the food itself, and fast-food outlets were described as uniquely suited to facilitating these interactions. Young people wanted to spend their money on foods they considered worthwhile, but this did not always relate to the most affordable foods. Adolescents wanted to put little effort into making food decisions and appreciated factors that helped them make quick decisions such as prominent placement and eye-catching promotions on foods they wanted to buy. Chain food outlets were valued as they offered familiar and frequently advertised foods, which minimized the effort needed for food decisions. Adolescents' sense of autonomy underpinned all themes. Participants described having limited opportunities to make their own food choices and they did not want to waste these buying unappealing 'healthy' foods. Interventions and government policies should align with adolescents' experiences and values relating to food choice to ensure that they are effective with this important age group.

Influences of the community and consumer nutrition environment on the food purchases and dietary behaviors of adolescents: A systematic review

Adolescence is a period of increased autonomy over decision-making, including food choices, and increased exposure to influences outside the home, including the food environment. This review aims to synthesize the evidence for the influence of community nutrition environments, spatial access to food outlets, and consumer nutrition environments, environments inside food outlets, on adolescent food purchasing and dietary behaviors in high-income countries. Six databases were searched for articles published before January 2023. Results were synthesized using a vote-counting technique and effect direction plots that record the direction of the effect in relation to the anticipated relationship with health. Thirty-four observational and two intervention studies met the inclusion criteria. In the 13 studies assessing adolescent exposure to healthy community nutrition environments, results did not show clear associations with dietary and purchasing outcomes. Thirty studies assessed adolescents' exposure to unhealthy community nutrition environments with the majority (n = 17/30, 57%) reporting results showing that greater exposure to food outlets classified as unhealthy was associated with less healthy food purchases and dietary intakes. Inconsistent results were observed across the seven studies investigating associations with the consumer environment. Further research in these areas, including more high-quality intervention studies, may help to develop policy strategies to improve adolescents' dietary behaviors.

Real-life experiments in supermarkets to encourage healthy dietary-related behaviours: opportunities, challenges and lessons learned

BACKGROUND

Supermarkets are the primary source of food for many people yet their full potential as a setting to encourage healthy dietary-related behaviours remains underutilised. Sharing the experiences from research groups who have worked with supermarket chains to evaluate strategies that promote healthy eating could improve the efficiency of building such relationships and enhance the design quality of future research studies.

METHODS

A collective case study approach was used to synthesise experiences of engaging and sustaining research collaborations with national supermarket chains to test the effectiveness of health-focused in-store interventions. The collective narrative covers studies conducted in three high-income countries: Australia, the Netherlands and the United Kingdom.

RESULTS

We have distilled our experiences and lessons learned into six recommendations for conducting high quality public health research with commercial supermarket chains. These include: (i) using personal contacts, knowledge of supermarket activities and engaging executive management to establish a partnership and allowing time to build trust; (ii) using scientifically robust study designs with appropriate sample size calculations; (iii) formalising data exchange arrangements and allocating adequate resource for data extraction and re-categorisation; (iv) assessing effects at individual/households level where possible; (v) designing a mixed-methods process evaluation to measure intervention fidelity, dose and unintended consequences; and (vi) ensuring scientific independence through formal contract agreements.

CONCLUSIONS

Our collective experiences of working in non-financial partnerships with national supermarket chains could be useful for other research groups looking to develop and implement supermarket studies in an efficient manner. Further evidence from real-life supermarket interventions is necessary to identify sustainable strategies that can improve population diet and maintain necessary commercial outcomes.

Inequalities in energy drink consumption among UK adolescents: a mixed-methods study

OBJECTIVE

To examine energy drink consumption among adolescents in the United Kingdom (UK) and associations with deprivation and dietary inequalities.

DESIGN

Quantitative dietary and demographic data from the National Diet and Nutrition Survey (NDNS) repeated cross-sectional survey were analysed using logistic regression models. Qualitative data from semi-structured interviews were analysed using inductive thematic analysis.

SETTING

UK.

PARTICIPANTS

Quantitative data: nationally representative sample of 2587 adolescents aged 11-18 years. Qualitative data: 20 parents, 9 teachers, and 28 adolescents from Hampshire, UK.

RESULTS

NDNS data showed adolescents' consumption of energy drinks was associated with poorer dietary quality (OR 0.46 per SD; 95% CI 0.37, 0.58; p<0.001). Adolescents from more deprived areas and lower income households were more likely to consume energy drinks than those in more affluent areas and households (OR 1.40; 95%CI 1.16, 1.69; p<0.001; OR 0.98 per £1000; 95%CI, 0.96, 0.99; p<0.001 respectively). Between 2008 and 2016, energy drink consumption among adolescents living in the most deprived areas increased, but decreased among those living in the most affluent neighbourhoods (p=0.04). Qualitative data identified three themes. First, many adolescents drink energy drinks because of their friends and because the unbranded drinks are cheap. Second, energy drink consumption clusters with other unhealthy eating behaviours and adolescents don't know why energy drinks are unhealthy. Third, adolescents believe voluntary bans in retail outlets and schools do not work.

CONCLUSIONS

This study supports the introduction of age-dependent legal restrictions on the sale of energy drinks which may help curb existing socio-economic disparities in adolescents' energy drink intake.

Modeling the impact of calorie-reduction interventions on population prevalence and inequalities in childhood obesity in the Southampton Women's Survey

BACKGROUND

In the United Kingdom, rates of childhood obesity are high and inequalities in obesity have widened in recent years. Children with obesity face heightened risks of living with obesity as adults and suffering from associated morbidities. Addressing population prevalence and inequalities in childhood obesity is a key priority for public health policymakers in the United Kingdom and elsewhere. Where randomized controlled trials are not possible, potential policy actions can be simulated using causal modeling techniques.

OBJECTIVES

Using data from the Southampton Women's Survey (SWS), a cohort with high quality dietary and lifestyle data, the potential impact of policy-relevant calorie-reduction interventions on population prevalence and inequalities of childhood obesity was investigated.

METHODS

Predicted probabilities of obesity (using UK90 cut-offs) at age 6-7 years were estimated from logistic marginal structural models adjusting for observed calorie consumption at age 3 years (using food diaries) and confounding. A series of policy-relevant intervention scenarios were modeled to simulate reductions in energy intake (differing in effectiveness, the targeting mechanisms, and level of uptake).

RESULTS

At age 6-7 years, 8.3% of children were living with obesity, after accounting for observed energy intake and confounding. A universal intervention to lower median energy intake to the estimated average requirement (a 13% decrease), with an uptake of 75%, reduced obesity prevalence by 1% but relative and absolute inequalities remained broadly unchanged.

CONCLUSIONS

Simulated interventions substantially reduced population prevalence of obesity, which may be useful in informing policymakers.

Altering product placement to create a healthier layout in supermarkets: Outcomes on store sales, customer purchasing, and diet in a prospective matched controlled cluster study

BACKGROUND

Previous product placement trials in supermarkets are limited in scope and outcome data collected. This study assessed the effects on store-level sales, household-level purchasing, and dietary behaviours of a healthier supermarket layout.

METHODS AND FINDINGS

This is a prospective matched controlled cluster trial with 2 intervention components: (i) new fresh fruit and vegetable sections near store entrances (replacing smaller displays at the back) and frozen vegetables repositioned to the entrance aisle, plus (ii) the removal of confectionery from checkouts and aisle ends opposite. In this pilot study, the intervention was implemented for 6 months in 3 discount supermarkets in England. Three control stores were matched on store sales and customer profiles and neighbourhood deprivation. Women customers aged 18 to 45 years, with loyalty cards, were assigned to the intervention (n = 62) or control group (n = 88) of their primary store. The trial registration number is NCT03518151. Interrupted time series analysis showed that increases in store-level sales of fruits and vegetables were greater in intervention stores than predicted at 3 (1.71 standard deviations (SDs) (95% CI 0.45, 2.96), P = 0.01) and 6 months follow-up (2.42 SDs (0.22, 4.62), P = 0.03), equivalent to approximately 6,170 and approximately 9,820 extra portions per store, per week, respectively. The proportion of purchasing fruits and vegetables per week rose among intervention participants at 3 and 6 months compared to control participants (0.2% versus -3.0%, P = 0.22; 1.7% versus -3.5%, P = 0.05, respectively). Store sales of confectionery were lower in intervention stores than predicted at 3 (-1.05 SDs (-1.98, -0.12), P = 0.03) and 6 months (-1.37 SDs (-2.95, 0.22), P = 0.09), equivalent to approximately 1,359 and approximately 1,575 fewer portions per store, per week, respectively; no differences were observed for confectionery purchasing. Changes in dietary variables were predominantly in the expected direction for health benefit. Intervention implementation was not within control of the research team, and stores could not be randomised. It is a pilot study, and, therefore, not powered to detect an effect.

CONCLUSIONS

Healthier supermarket layouts can improve the nutrition profile of store sales and likely improve household purchasing and dietary quality. Placing fruits and vegetables near store entrances should be considered alongside policies to limit prominent placement of unhealthy foods.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03518151 (pre-results).

Resources in women's social networks for food shopping are more strongly associated with better dietary quality than people: A cross-sectional study

When healthy people are part of an individual's social network, those individuals will have better dietary quality. Little, however, is known about whether social networks for food shopping, including both people and resources (e.g. recipes, weight loss programmes and food advertisements) are associated with dietary quality. The aim of this study was to explore the relationship between social networks for food shopping and dietary quality, and whether this differs for people and resources, among women aged 18-45 years. A total of 129 participants completed a cross-sectional questionnaire including an ego-centric Social Network Exposure tool and short Food Frequency Questionnaire. Associations between dietary quality and type of network member, perceived healthiness and support for healthy shopping choices were explored using linear regression models. Analyses revealed that participants who nominated people in their food shopping social network that eat healthily or support healthy food shopping had better dietary quality (β = 0.16 SD per 1-point change on a 4-point scale, 95%CI -0.06, 0.39; β = 0.20, 95%CI -0.07, 0.46, respectively). Resources in participants' food shopping social networks which promote healthy eating or support healthy shopping were associated with better dietary quality. These associations remained robust after adjustment for confounding variables identified using a directed acyclic graph (β = 0.31 SD per 1-point change on a 4-point scale, 95%CI 0.03, 0.58; β = 0.44, 95%CI 0.09, 0.79 respectively). The results were strengthened when the outcome was multiplied by frequency of contact (β = 0.33, 95%CI 0.05, 0.61; β = 0.47, 95%CI 0.11, 0.83 respectively). This study suggests that resources which promote healthy eating and healthy food shopping have a stronger association with dietary quality than social support from people. Further research is required in a larger sample, including multiple time-points, to confirm these findings.

Women's perceptions of factors influencing their food shopping choices and how supermarkets can support them to make healthier choices

OBJECTIVES

To examine women's perceptions of factors that influence their food shopping choices, particularly in relation to store layout, and their views on ways that supermarkets could support healthier choices.

DESIGN

This qualitative cross-sectional study used semi-structured telephone interviews to ask participants the reasons for their choice of supermarket and factors in-store that prompted their food selections. The actions supermarkets, governments and customers could take to encourage healthier food choices were explored with women. Thematic analysis was conducted to identify key themes.

SETTING

Six supermarkets across England.

PARTICIPANTS

Twenty women customers aged 18-45 years.

RESULTS

Participants had a median age of 39.5 years (IQR: 35.1, 42.3), a median weekly grocery spend of £70 (IQR: 50, 88), and 44% had left school aged 16 years. Women reported that achieving value for money, feeling hungry, tired, or stressed, and meeting family members' food preferences influenced their food shopping choices. The physical environment was important, including product quality and variety, plus ease of accessing the store or products in-store. Many participants described how they made unintended food selections as a result of prominent placement of unhealthy products in supermarkets, even if they adopted more conscious approaches to food shopping (i.e. written or mental lists). Participants described healthy eating as a personal responsibility, but some stated that governments and supermarkets could be more supportive.

CONCLUSIONS

This study highlighted that in-store environments can undermine intentions to purchase and consume healthy foods. Creating healthier supermarket environments could reduce the burden of personal responsibility for healthy eating, by making healthier choices easier. Future research could explore the interplay of personal, societal and commercial responsibility for food choices and health status.

The EU Child Cohort Network's core data: establishing a set of findable, accessible, interoperable and re-usable (FAIR) variables

The Horizon2020 LifeCycle Project is a cross-cohort collaboration which brings together data from multiple birth cohorts from across Europe and Australia to facilitate studies on the influence of early-life exposures on later health outcomes. A major product of this collaboration has been the establishment of a FAIR (findable, accessible, interoperable and reusable) data resource known as the EU Child Cohort Network. Here we focus on the EU Child Cohort Network's core variables. These are a set of basic variables, derivable by the majority of participating cohorts and frequently used as covariates or exposures in lifecourse research. First, we describe the process by which the list of core variables was established. Second, we explain the protocol according to which these variables were harmonised in order to make them interoperable. Third, we describe the catalogue developed to ensure that the network's data are findable and reusable. Finally, we describe the core data, including the proportion of variables harmonised by each cohort and the number of children for whom harmonised core data are available. EU Child Cohort Network data will be analysed using a federated analysis platform, removing the need to physically transfer data and thus making the data more accessible to researchers. The network will add value to participating cohorts by increasing statistical power and exposure heterogeneity, as well as facilitating cross-cohort comparisons, cross-validation and replication. Our aim is to motivate other cohorts to join the network and encourage the use of the EU Child Cohort Network by the wider research community.

Outcomes of Acute Stroke Patients Requiring Mechanical Ventilation: Study Protocol for the SPICE Multicenter Prospective Observational Study

BACKGROUND

Care pathways and long-term outcomes of acute stroke patients requiring mechanical ventilation have not been thoroughly studied.

METHODS AND RESULTS

Stroke Prognosis in Intensive Care (SPICE) is a prospective multicenter cohort study which will be conducted in 34 intensive care units (ICUs) in the Paris, France area. Patients will be eligible if they meet all of the following inclusion criteria: (1) age of 18 years or older; (2) acute stroke (i.e., ischemic stroke, intracranial hemorrhage, or subarachnoid hemorrhage) diagnosed on neuroimaging; (3) ICU admission within 7 days before or after stroke onset; and (4) need for mechanical ventilation for a duration of at least 24 h. Patients will be excluded if they meet any of the following: (1) stroke of traumatic origin; (2) refusal to participate; and (3) privation of liberty by administrative or judicial decision. The primary endpoint is poor functional outcome at 1 year, defined by a score of 4 to 6 on the modified Rankin scale (mRS), indicating severe disability or death. Main secondary endpoints will include decisions to withhold or withdraw care, mRS scores at 3 and 6 months, and health-related quality of life at 1 year.

CONCLUSIONS

The SPICE multicenter study will investigate 1-year outcomes, ethical issues, as well as care pathways of acute stroke patients requiring invasive ventilation in the ICU. Gathered data will delineate human resources and facilities needs for adequate management. The identification of prognostic factors at the acute phase will help to identify patients who may benefit from prolonged intensive care and rehabilitation.

TRIAL REGISTRATION

NCT03335995.

Development of a short food frequency questionnaire to assess diet quality in UK adolescents using the National Diet and Nutrition Survey

BACKGROUND

UK adolescents consume fewer fruits and vegetables and more free sugars than any other age group. Established techniques to understand diet quality can be difficult to use with adolescents because of high participant burden. This study aimed to identify key foods that indicate variation in diet quality in UK adolescents for inclusion in a short food frequency questionnaire (FFQ) and to investigate the associations between adolescent diet quality, nutritional biomarkers and socio-demographic factors.

METHODS

Dietary, demographic and biomarker data from waves 1-8 of the National Diet and Nutrition Survey rolling programme were used (n=2587; aged 11-18 years; 50% boys; n=≤997 biomarker data). Principal component analysis (PCA) was applied to 139 food groups to identify the key patterns within the data. Two diet quality scores, a 139-group and 20-group, were calculated using the PCA coefficients for each food group and multiplying by their standardised reported frequency of consumption and then summing across foods. The foods with the 10 strongest positive and 10 strongest negative coefficients from the PCA results were used for the 20-group score. Scores were standardised to have a zero mean and standard deviation of one.

RESULTS

The first PCA component explained 3.0% of variance in the dietary data and described a dietary pattern broadly aligned with UK dietary recommendations. A correlation of 0.87 was observed between the 139-group and 20-group scores. Bland-Altman mean difference was 0.00 and 95% limits of agreement were - 0.98 to 0.98 SDs. Correlations, in the expected direction, were seen between each nutritional biomarker and both scores; results attenuated slightly for the 20-group score compared to the 139-group score. Better diet quality was observed among girls, non-white populations and in those from higher socio-economic backgrounds for both scores.

CONCLUSIONS

The diet quality score based on 20 food groups showed reasonable agreement with the 139-group score. Both scores were correlated with nutritional biomarkers. A short 20-item FFQ can provide a meaningful and easy-to-implement tool to assess diet quality in large scale observational and intervention studies with adolescents.

Changes in parental smoking during pregnancy and risks of adverse birth outcomes and childhood overweight in Europe and North America: An individual participant data meta-analysis of 229,000 singleton births

BACKGROUND

Fetal smoke exposure is a common and key avoidable risk factor for birth complications and seems to influence later risk of overweight. It is unclear whether this increased risk is also present if mothers smoke during the first trimester only or reduce the number of cigarettes during pregnancy, or when only fathers smoke. We aimed to assess the associations of parental smoking during pregnancy, specifically of quitting or reducing smoking and maternal and paternal smoking combined, with preterm birth, small size for gestational age, and childhood overweight.

METHODS AND FINDINGS

We performed an individual participant data meta-analysis among 229,158 families from 28 pregnancy/birth cohorts from Europe and North America. All 28 cohorts had information on maternal smoking, and 16 also had information on paternal smoking. In total, 22 cohorts were population-based, with birth years ranging from 1991 to 2015. The mothers' median age was 30.0 years, and most mothers were medium or highly educated. We used multilevel binary logistic regression models adjusted for maternal and paternal sociodemographic and lifestyle-related characteristics. Compared with nonsmoking mothers, maternal first trimester smoking only was not associated with adverse birth outcomes but was associated with a higher risk of childhood overweight (odds ratio [OR] 1.17 [95% CI 1.02-1.35], P value = 0.030). Children from mothers who continued smoking during pregnancy had higher risks of preterm birth (OR 1.08 [95% CI 1.02-1.15], P value = 0.012), small size for gestational age (OR 2.15 [95% CI 2.07-2.23], P value < 0.001), and childhood overweight (OR 1.42 [95% CI 1.35-1.48], P value < 0.001). Mothers who reduced the number of cigarettes between the first and third trimester, without quitting, still had a higher risk of small size for gestational age. However, the corresponding risk estimates were smaller than for women who continued the same amount of cigarettes throughout pregnancy (OR 1.89 [95% CI 1.52-2.34] instead of OR 2.20 [95% CI 2.02-2.42] when reducing from 5-9 to ≤4 cigarettes/day; OR 2.79 [95% CI 2.39-3.25] and OR 1.93 [95% CI 1.46-2.57] instead of OR 2.95 [95% CI 2.75-3.15] when reducing from ≥10 to 5-9 and ≤4 cigarettes/day, respectively [P values < 0.001]). Reducing the number of cigarettes during pregnancy did not affect the risks of preterm birth and childhood overweight. Among nonsmoking mothers, paternal smoking was associated with childhood overweight (OR 1.21 [95% CI 1.16-1.27], P value < 0.001) but not with adverse birth outcomes. Limitations of this study include the self-report of parental smoking information and the possibility of residual confounding. As this study only included participants from Europe and North America, results need to be carefully interpreted regarding other populations.

CONCLUSIONS

We observed that as compared to nonsmoking during pregnancy, quitting smoking in the first trimester is associated with the same risk of preterm birth and small size for gestational age, but with a higher risk of childhood overweight. Reducing the number of cigarettes, without quitting, has limited beneficial effects. Paternal smoking seems to be associated, independently of maternal smoking, with the risk of childhood overweight. Population strategies should focus on parental smoking prevention before or at the start, rather than during, pregnancy.

Protocol of a natural experiment to evaluate a supermarket intervention to improve food purchasing and dietary behaviours of women (WRAPPED study) in England: a prospective matched controlled cluster design

INTRODUCTION

Poor diet is a leading risk factor for non-communicable diseases and costs the National Health Service £5.8 billion annually. Product placement strategies used extensively in food outlets, like supermarkets, can influence customers' preferences. Policy-makers, including the UK Government, are considering legislation to ensure placement strategies promote healthier food purchasing and dietary habits. High-quality scientific evidence is needed to inform future policy action. This study will assess whether healthier placement strategies in supermarkets improve household purchasing patterns and the diets of more than one household member.

METHODS AND ANALYSES

This natural experiment, with a prospective matched controlled cluster design, is set in discount supermarkets across England. The primary objective is to investigate whether enhanced placement of fresh fruit and vegetables improves household-level purchasing of these products after 6 months. Secondary objectives will examine: (1) differences in intervention effects on purchasing by level of educational attainment, (2) intervention effects on the dietary quality of women and their young children, (3) intervention effects on store-level sales of fruit and vegetables and (4) cost-effectiveness of the intervention from individual, retailer and societal perspectives. Up to 810 intervention and 810 control participants will be recruited from 18 intervention and 18 matched control stores. Eligible participants will be women aged 18-45 years, who hold a loyalty card and shop in a study store. Each control store will be matched to an intervention store on: (1) sales profile, (2) neighbourhood deprivation and (3) customer profile. A detailed process evaluation will assess intervention implementation, mechanisms of impact and, social and environmental contexts.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the University of Southampton, Faculty of Medicine Ethics Committee (ID 20986.A5). Primary, secondary and process evaluation results will be submitted for publication in peer-reviewed scientific journals and shared with policy-makers.

TRIAL REGISTRATION NUMBER

NCT03573973; Pre-results.

Does early introduction of solid feeding lead to early cessation of breastfeeding?

Mixed milk feeding increases the likelihood of breastfeeding cessation, but it is not known if solid feeding (SF) has the same effect. We have identified 10,407 infants breastfed for at least 8-10 weeks from three large U.K. studies (Avon Longitudinal Study of Parents and Children [ALSPAC; born 1990-1991], Southampton Woman's Survey [SWS; 1998-2008], and Infant Feeding Survey 2010 [IFS 2010]) to investigate the associations between early SF and breastfeeding cessation. In the earliest study (ALSPAC), 67% had started SF before the age of 4 months, but in the latest (IFS), only 23% had started before 4 months. Solid food introduction before 4 months was associated with stopping breastfeeding before 6 months in all three cohorts, with little effect of adjustment for maternal sociodemographic characteristics (Poisson regression, adjusted prevalence ratios: ALSPAC 1.55, [95% confidence interval 1.4, 1.8], SWS 1.13 [1.0, 1.3], IFS 1.10 [1.1, 1.3]). Using Cox regression, adjusted hazard ratios for breastfeeding cessation compared with SF after 5 months were 2.07 (1.8, 2.4) for SF before 4 and 1.51 (1.3, 1.8) at 4-5 months for ALSPAC and 1.25 (1.1, 1.5) and 1.15 (1.0, 1.3) for SWS. Earlier introduction of solids was associated with a shorter duration of breastfeeding, particularly in cohorts where earlier introduction of solids was the norm, with a dose-response relationship, which was not explained by background social characteristics. As mothers most commonly introduced solids in the month prior to the then recommended age, continuing to recommend deferring solids to the age of 6 months is important to support sustained breastfeeding.

Association of Gestational Weight Gain With Adverse Maternal and Infant Outcomes

Importance

Both low and high gestational weight gain have been associated with adverse maternal and infant outcomes, but optimal gestational weight gain remains uncertain and not well defined for all prepregnancy weight ranges.

Objectives

To examine the association of ranges of gestational weight gain with risk of adverse maternal and infant outcomes and estimate optimal gestational weight gain ranges across prepregnancy body mass index categories.

Design, Setting, and Participants

Individual participant-level meta-analysis using data from 196 670 participants within 25 cohort studies from Europe and North America (main study sample). Optimal gestational weight gain ranges were estimated for each prepregnancy body mass index (BMI) category by selecting the range of gestational weight gain that was associated with lower risk for any adverse outcome. Individual participant-level data from 3505 participants within 4 separate hospital-based cohorts were used as a validation sample. Data were collected between 1989 and 2015. The final date of follow-up was December 2015.

Exposures

Gestational weight gain.

Main Outcomes and Measures

The main outcome termed any adverse outcome was defined as the presence of 1 or more of the following outcomes: preeclampsia, gestational hypertension, gestational diabetes, cesarean delivery, preterm birth, and small or large size for gestational age at birth.

Results

Of the 196 670 women (median age, 30.0 years [quartile 1 and 3, 27.0 and 33.0 years] and 40 937 were white) included in the main sample, 7809 (4.0%) were categorized at baseline as underweight (BMI <18.5); 133 788 (68.0%), normal weight (BMI, 18.5-24.9); 38 828 (19.7%), overweight (BMI, 25.0-29.9); 11 992 (6.1%), obesity grade 1 (BMI, 30.0-34.9); 3284 (1.7%), obesity grade 2 (BMI, 35.0-39.9); and 969 (0.5%), obesity grade 3 (BMI, ≥40.0). Overall, any adverse outcome occurred in 37.2% (n = 73 161) of women, ranging from 34.7% (2706 of 7809) among women categorized as underweight to 61.1% (592 of 969) among women categorized as obesity grade 3. Optimal gestational weight gain ranges were 14.0 kg to less than 16.0 kg for women categorized as underweight; 10.0 kg to less than 18.0 kg for normal weight; 2.0 kg to less than 16.0 kg for overweight; 2.0 kg to less than 6.0 kg for obesity grade 1; weight loss or gain of 0 kg to less than 4.0 kg for obesity grade 2; and weight gain of 0 kg to less than 6.0 kg for obesity grade 3. These gestational weight gain ranges were associated with low to moderate discrimination between those with and those without adverse outcomes (range for area under the receiver operating characteristic curve, 0.55-0.76). Results for discriminative performance in the validation sample were similar to the corresponding results in the main study sample (range for area under the receiver operating characteristic curve, 0.51-0.79).

Conclusions and Relevance

In this meta-analysis of pooled individual participant data from 25 cohort studies, the risk for adverse maternal and infant outcomes varied by gestational weight gain and across the range of prepregnancy weights. The estimates of optimal gestational weight gain may inform prenatal counseling; however, the optimal gestational weight gain ranges had limited predictive value for the outcomes assessed.

The association between crowding within households and behavioural problems in children: Longitudinal data from the Southampton Women's Survey

BACKGROUND

In England, nearly one child in ten lives in overcrowded housing. Crowding is likely to worsen with increasing population size, urbanisation, and the ongoing concerns about housing shortages. Children with behavioural difficulties are at increased risk of mental and physical health problems and poorer employment prospects.

OBJECTIVE

To test the association between the level of crowding in the home and behavioural problems in children, and to explore what factors might explain the relationship.

METHODS

Mothers of 2576 children from the Southampton Women's Survey population-based mother-offspring cohort were interviewed. Crowding was measured at age 2 years by people per room (PPR) and behavioural problems assessed at age 3 years with the Strengths and Difficulties Questionnaire (SDQ). Both were analysed as continuous measures, and multivariable linear regression models were fitted, adjusting for confounding factors: gender, age, single-parent family, maternal education, receipt of benefits, and social class. Potential mediators were assessed with formal mediation analysis.

RESULTS

The characteristics of the sample were broadly representative of the population in England. Median (IQR) SDQ score was 9 (6-12) and PPR was 0.75 (0.6-1). In households that were more crowded, children tended to have more behavioural problems (by 0.20 SDQ points (95% CI 0.08, 0.32) per additional 0.2 PPR, adjusting for confounding factors). This relationship was partially mediated by greater maternal stress, less sleep, and strained parent-child interactions.

CONCLUSIONS

Living in a more crowded home was associated with a greater risk of behavioural problems, independent of confounding factors. The findings suggest that improved housing might reduce childhood behavioural problems and that families living in crowded circumstances might benefit from greater support.

Impact of maternal body mass index and gestational weight gain on pregnancy complications: an individual participant data meta-analysis of European, North American and Australian cohorts

OBJECTIVE

To assess the separate and combined associations of maternal pre-pregnancy body mass index (BMI) and gestational weight gain with the risks of pregnancy complications and their population impact.

DESIGN

Individual participant data meta-analysis of 39 cohorts.

SETTING

Europe, North America, and Oceania.

POPULATION

265 270 births.

METHODS

Information on maternal pre-pregnancy BMI, gestational weight gain, and pregnancy complications was obtained. Multilevel binary logistic regression models were used.

MAIN OUTCOME MEASURES

Gestational hypertension, pre-eclampsia, gestational diabetes, preterm birth, small and large for gestational age at birth.

RESULTS

Higher maternal pre-pregnancy BMI and gestational weight gain were, across their full ranges, associated with higher risks of gestational hypertensive disorders, gestational diabetes, and large for gestational age at birth. Preterm birth risk was higher at lower and higher BMI and weight gain. Compared with normal weight mothers with medium gestational weight gain, obese mothers with high gestational weight gain had the highest risk of any pregnancy complication (odds ratio 2.51, 95% CI 2.31- 2.74). We estimated that 23.9% of any pregnancy complication was attributable to maternal overweight/obesity and 31.6% of large for gestational age infants was attributable to excessive gestational weight gain.

CONCLUSIONS

Maternal pre-pregnancy BMI and gestational weight gain are, across their full ranges, associated with risks of pregnancy complications. Obese mothers with high gestational weight gain are at the highest risk of pregnancy complications. Promoting a healthy pre-pregnancy BMI and gestational weight gain may reduce the burden of pregnancy complications and ultimately the risk of maternal and neonatal morbidity.

TWEETABLE ABSTRACT

Promoting a healthy body mass index and gestational weight gain might reduce the population burden of pregnancy complications.

A longitudinal investigation of the glass-ceiling in nursing

Purpose

The purpose of this paper is to present a longitudinal, qualitative study exploring changes in the attributional constructions of sense-making in the perceptions and lived experiences of the glass-ceiling among a cohort of female mental health nurses in the National Health Service who participated in a 12-month multi-faceted career and leadership development pilot programme compared to a matched control group.

Design/methodology/approach

The authors interviewed 27 female mental health nurses in the UK who participated in a multi-faceted development programme specifically designed to support female nurses secure career advancement and 27 members of a matched control group who did not experience the programme. Participants engaged in semi-structured telephone interviews at three separate time points (six months apart) over a 12-month period.

Findings

Programme participants differed in their attributional constructions of sense-making in relation to the glass-ceiling over time compared to the matched control group, e.g., triggering understandings and awakenings and re-evaluating the glass-ceiling above when promoted. Findings are used to theorise about the glass-ceiling as a concept that shifts and changes over time as a function of experience.

Practical implications

Practical implications include important organisational outcomes in relation to fostering the career advancement and retention of talented female leaders at all career stages.

Originality/value

The authors present the first known longitudinal, qualitative study to explore changes in attributional constructions of sense-making in perceptions and experiences of the glass-ceiling among female nurses over time compared to a matched control group.

Gestational weight gain charts for different body mass index groups for women in Europe, North America, and Oceania

BACKGROUND

Gestational weight gain differs according to pre-pregnancy body mass index and is related to the risks of adverse maternal and child health outcomes. Gestational weight gain charts for women in different pre-pregnancy body mass index groups enable identification of women and offspring at risk for adverse health outcomes. We aimed to construct gestational weight gain reference charts for underweight, normal weight, overweight, and grades 1, 2 and 3 obese women and to compare these charts with those obtained in women with uncomplicated term pregnancies.

METHODS

We used individual participant data from 218,216 pregnant women participating in 33 cohorts from Europe, North America, and Oceania. Of these women, 9065 (4.2%), 148,697 (68.1%), 42,678 (19.6%), 13,084 (6.0%), 3597 (1.6%), and 1095 (0.5%) were underweight, normal weight, overweight, and grades 1, 2, and 3 obese women, respectively. A total of 138, 517 women from 26 cohorts had pregnancies with no hypertensive or diabetic disorders and with term deliveries of appropriate for gestational age at birth infants. Gestational weight gain charts for underweight, normal weight, overweight, and grade 1, 2, and 3 obese women were derived by the Box-Cox t method using the generalized additive model for location, scale, and shape.

RESULTS

We observed that gestational weight gain strongly differed per maternal pre-pregnancy body mass index group. The median (interquartile range) gestational weight gain at 40 weeks was 14.2 kg (11.4-17.4) for underweight women, 14.5 kg (11.5-17.7) for normal weight women, 13.9 kg (10.1-17.9) for overweight women, and 11.2 kg (7.0-15.7), 8.7 kg (4.3-13.4) and 6.3 kg (1.9-11.1) for grades 1, 2, and 3 obese women, respectively. The rate of weight gain was lower in the first half than in the second half of pregnancy. No differences in the patterns of weight gain were observed between cohorts or countries. Similar weight gain patterns were observed in mothers without pregnancy complications.

CONCLUSIONS

Gestational weight gain patterns are strongly related to pre-pregnancy body mass index. The derived charts can be used to assess gestational weight gain in etiological research and as a monitoring tool for weight gain during pregnancy in clinical practice.

Does early onset asthma increase childhood obesity risk? A pooled analysis of 16 European cohorts

The parallel epidemics of childhood asthma and obesity over the past few decades have spurred research into obesity as a risk factor for asthma. However, little is known regarding the role of asthma in obesity incidence. We examined whether early-onset asthma and related phenotypes are associated with the risk of developing obesity in childhood.This study includes 21 130 children born from 1990 to 2008 in Denmark, France, Germany, Greece, Italy, The Netherlands, Spain, Sweden and the UK. We followed non-obese children at 3-4 years of age for incident obesity up to 8 years of age. Physician-diagnosed asthma, wheezing and allergic rhinitis were assessed up to 3-4 years of age.Children with physician-diagnosed asthma had a higher risk for incident obesity than those without asthma (adjusted hazard ratio (aHR) 1.66, 95% CI 1.18-2.33). Children with active asthma (wheeze in the last 12 months and physician-diagnosed asthma) exhibited a higher risk for obesity (aHR 1.98, 95% CI 1.31-3.00) than those without wheeze and asthma. Persistent wheezing was associated with increased risk for incident obesity compared to never wheezers (aHR 1.51, 95% CI 1.08-2.09).Early-onset asthma and wheezing may contribute to an increased risk of developing obesity in later childhood.

Relation of placental alkaline phosphatase expression in human term placenta with maternal and offspring fat mass

INTRODUCTION

Alkaline phosphatase is implicated in intestinal lipid transport and in the development of obesity. Placental alkaline phosphatase is localised to the microvillous plasma membrane of the placental syncytiotrophoblast at the maternal-fetal interface, but its role is unclear. We investigated the relations of placental alkaline phosphatase activity and mRNA expression with maternal body composition and offspring fat mass in humans.

METHODS

Term human placentas from the UK Birthright cohort (n = 52) and the Southampton Women's Survey (SWS) (n = 95) were studied. In the Birthright cohort, alkaline phosphatase activity was measured in placental microvillous plasma membrane vesicles. In the SWS, alkaline phosphatase mRNA was measured using Nanostring. Alkaline phosphatase gene expression was compared to other lipid-related genes.

RESULTS

In Birthright samples placental microvillous plasma membrane alkaline phosphatase activity was positively associated with maternal triceps skinfold thickness and BMI (β = 0.04 (95% CI: 0.01-0.06) and β = 0.02 (0.00-0.03) µmol/mg protein/min per SD, P = 0.002 and P = 0.05, respectively) after adjusting for potential confounders. In SWS samples placental alkaline phosphatase mRNA expression in term placenta was positively associated with maternal triceps skinfold (β = 0.24 (0.04, 0.44) SD/SD, P = 0.02), had no association with neonatal %fat mass (β = 0.01 (-0.20 to 0.21) SD/SD, P = 0.93) and was negatively correlated with %fat mass at ages 4 (β = -0.28 (-0.52 to -0.04) SD/SD, P = 0.02), 6-7 (β = -0.25 (-0.49 to -0.02) SD/SD, P = 0.03) years. When compared with placental expression of other genes, alkaline phosphatase expression was positively related to genes including the lysophosphatidylcholine transporter MFSD2A (major facilitator superfamily domain containing 2A, P < 0.001) and negatively related to genes including the fatty acid transport proteins 2 and 3 (P = 0.001, P < 0.001).

CONCLUSIONS

Our findings suggest relationships between placental alkaline phosphatase and both maternal and childhood adiposity. The inverse relationship between placental alkaline phosphatase gene expression and childhood %fat mass suggests that placental alkaline phosphatase may help to protect the foetus from the adverse effects of maternal obesity.

Electrodynamic Heart Model Construction and ECG Simulation

Objectives: In this paper, we present a unified electrodynamic heart model that permits simulations of the body surface potentials generated by the heart in motion. The inclusion of motion in the heart model significantly improves the accuracy of the simulated body surface potentials and therefore also the 12-lead ECG.

Methods: The key step is to construct an electromechanical heart model. The cardiac excitation propagation is simulated by an electrical heart model, and the resulting cardiac active forces are used to calculate the ventricular wall motion based on a mechanical model. The source-field point relative position changes during heart systole and diastole. These can be obtained, and then used to calculate body surface ECG based on the electrical heart-torso model.

Results: An electromechanical biventricular heart model is constructed and a standard 12-lead ECG is simulated. Compared with a simulated ECG based on the static electrical heart model, the simulated ECG based on the dynamic heart model is more accordant with a clinically recorded ECG, especially for the ST segment and T wave of a V1-V6 lead ECG. For slight-degree myocardial ischemia ECG simulation, the ST segment and T wave changes can be observed from the simulated ECG based on a dynamic heart model, while the ST segment and T wave of simulated ECG based on a static heart model is almost unchanged when compared with a normal ECG.

Conclusions: This study confirms the importance of the mechanical factor in the ECG simulation. The dynamic heart model could provide more accurate ECG simulation, especially for myocardial ischemia or infarction simulation, since the main ECG changes occur at the ST segment and T wave, which correspond with cardiac systole and diastole phases.

Technical Note: Experimental results from a prototype high-field inline MRI-linac

PURPOSE

The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac.

METHODS

The magnet is a 1.5 T MRI system (Sonata, Siemens Healthcare) was located in a purpose built radiofrequency (RF) cage enabling shielding from and close proximity to a linear accelerator with inline (and future perpendicular) orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multileaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-linac experiments was performed to investigate (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array; and (3) electron contamination effects measured using Gafchromic film and an electronic portal imaging device (EPID).

RESULTS

(1) Image quality was unaffected by the radiation beam with the macropodine phantom image with the beam on being almost identical to the image with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background intensity when the radiation beam was on. (3) Film and EPID measurements demonstrated electron focusing occurring along the centerline of the magnet axis.

CONCLUSIONS

A proof-of-concept high-field MRI-linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field inline MRI-linac and study a number of the technical challenges and solutions.

A systematic review of maternal smoking during pregnancy and fetal measurements with meta-analysis

BACKGROUND

Maternal smoking during pregnancy is linked to reduced birth weight but the gestation at onset of this relationship is not certain. We present a systematic review of the literature describing associations between maternal smoking during pregnancy and ultrasound measurements of fetal size, together with an accompanying meta-analysis.

METHODS

Studies were selected from electronic databases (OVID, EMBASE and Google Scholar) that examined associations between maternal smoking or smoke exposure and antenatal fetal ultrasound measurements. Outcome measures were first, second or third trimester fetal measurements.

RESULTS

There were 284 abstracts identified, 16 papers were included in the review and the meta-analysis included data from eight populations. Maternal smoking was associated with reduced second trimester head size (mean reduction 0.09 standard deviation (SD) [95% CI 0.01, 0.16]) and femur length (0.06 [0.01, 0.10]) and reduced third trimester head size (0.18 SD [0.13, 0.23]), femur length (0.27 SD [0.21, 0.32]) and estimated fetal weight (0.18 SD [0.11, 0.24]). Higher maternal cigarette consumption was associated with a lower z score for head size in the second (mean difference 0.09 SD [0, 0.19]) and third (0.15 SD [0.03, 0.26]) trimesters compared to lower consumption. Fetal measurements were not reduced for those whose mothers quit before or after becoming pregnant compared to mothers who had never smoked.

CONCLUSIONS

Maternal smoking during pregnancy is associated with reduced fetal measurements after the first trimester, particularly reduced head size and femur length. These effects may be attenuated if mothers quit or reduce cigarette consumption during pregnancy.

Synthesizing Dental Radiographs for Human Identification

The task of identifying human remains based on dental comparisons of post mortem (PM) and ante mortem (AM) radiographs is labor-intensive, subjective, and has several drawbacks, including: inherently poor image quality, difficulty matching the viewing angles in PM radiographs to those taken AM, and the fact that the state of the dental remains may entirely preclude the possibility of obtaining certain types of radiographs PM. The aim of the present study was to investigate the feasibility of using radiograph-like images reconstructed from PM x-ray computed tomography (CT) data to overcome the shortcomings of conventional radiographic comparison. Algorithms for computer synthesis of panoramic, periapical, and bitewing images are presented. The algorithms were evaluated with data from clinical examinations of two persons. The results demonstrate the efficacy of the CT-based approach and that, in comparison with conventional radiographs, the synthesized images exhibit minimal geometric distortion, reduced blurring, and reduced superimposition of oral structures.

Posterior reversible encephalopathy syndrome (PRES) and hypomagnesemia: A frequent association?

Posterior reversible encephalopathy syndrome (PRES) is a serious neurological condition encountered in various medical fields. Pathophysiological factor(s) common to PRES cases of apparently unrelated etiologies are yet to be found. Based on the hypothesis that hypomagnesemia might participate in the cascade leading to PRES, our study sought to verify whether hypomagnesemia is frequently associated with PRES regardless of etiology. From a retrospective study of a cohort of 57 patients presenting with PRES of different etiologies, presented here are the findings of 19 patients with available serum magnesium levels (SMLs) during PRES. In the acute phase of PRES, hypomagnesemia was present in all 19 patients in spite of differences in etiology (including immunosuppressive drugs, hypertensive encephalopathy, eclampsia, systemic lupus erythematosus, iatrogenic etiology and unknown). SMLs were within normal ranges prior to PRES and below normal ranges during the first 48h of PRES, with a significant decrease in SMLs during the acute phase. In this retrospective study, constant hypomagnesemia was observed during the acute phase of PRES regardless of its etiology. These results now require larger studies to assess the particular importance of acute hypomagnesemia in PRES and especially the possible need to treat PRES with magnesium sulfate.

Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection

An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm³. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage’s depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates its feasibility for potential use in ambulances as an effective and low cost diagnostic tool to assure timely triaging of intracranial hemorrhage patients.

Duration of sleep at 3 years of age is associated with fat and fat-free mass at 4 years of age: the Southampton Women's Survey

Many studies have shown that shorter sleep duration in childhood is associated with higher body mass index (BMI), and have proposed that it is due to an effect of sleep on adiposity. There is little evidence about the association of sleep with fat-free mass. This study examined the association between child's sleep duration at age 3 years and fat and fat-free mass at 4 years of age in a prospective cohort study of 302 boys and 285 girls. Study participants were taking part in the Southampton Women's Survey, a longitudinal study of mothers and children from preconception onwards. Total sleep duration at age 3 years was derived from parental report of night sleep and nap duration. Body composition was assessed by Dual-energy X-ray Absorptiometry (DXA) at 4 years. Mean total sleep duration was 11.5 hours. In linear regression analyses, adjusted for potentially confounding factors (maternal educational attainment, prepregnancy BMI, smoking during pregnancy, child's gestational age at birth, age at DXA, sex, age last breastfed, dietary quality at 3 years, TV watching and hours actively on the move and parental social class), shorter sleep in hours was associated with higher BMI (kg/m(2) ) [β: -0.2340, 95% confidence interval (CI): -0.373 to -0.096], a greater fat mass index (kg) (β: -0.1182, 95% CI: -0.218 to -0.018) and a greater fat-free mass index (kg) (β: -0.100, 95% CI: -0.185 to -0.015). Previous research suggested that the association between shorter sleep and higher body mass index is due to an effect on adiposity. Our findings are novel, suggesting that the relationship between sleep and BMI is also determined by an effect on muscle.

Antenatal blood pressure for prediction of pre-eclampsia, preterm birth, and small for gestational age babies: development and validation in two general population cohorts

STUDY QUESTION

Can routine antenatal blood pressure measurements between 20 and 36 weeks' gestation contribute to the prediction of pre-eclampsia and its associated adverse outcomes?

METHODS

This study used repeated antenatal measurements of blood pressure from 12 996 women in the Avon Longitudinal Study of Parents and Children (ALSPAC) to develop prediction models and validated these in 3005 women from the Southampton Women's Survey (SWS). A model based on maternal early pregnancy characteristics only (BMI, height, age, parity, smoking, existing and previous gestational hypertension and diabetes, and ethnicity) plus initial mean arterial pressure was compared with a model additionally including current mean arterial pressure, a model including the deviation of current mean arterial pressure from a stratified normogram, and a model including both at different gestational ages from 20-36 weeks.

STUDY ANSWER AND LIMITATIONS

The addition of blood pressure measurements from 28 weeks onwards improved prediction models compared with use of early pregnancy risk factors alone, but they contributed little to the prediction of preterm birth or small for gestational age. Though multiple imputation of missing data was used to increase the sample size and minimise selection bias, the validation sample might have been slightly underpowered as the number of cases of pre-eclampsia was just below the recommended 100. Several risk factors were self reported, potentially introducing measurement error, but this reflects how information would be obtained in clinical practice.

WHAT THIS STUDY ADDS

The addition of routinely collected blood pressure measurements from 28 weeks onwards improves predictive models for pre-eclampsia based on blood pressure in early pregnancy and other characteristics, facilitating a reduction in scheduled antenatal care.

FUNDING, COMPETING INTERESTS, DATA SHARING

UK Wellcome Trust, US National Institutes of Health, and UK Medical Research Council. Other funding sources for authors are detailed in the full online paper. With the exceptions of CM-W, HMI, and KMG there were no competing interests.

[Contribution of arterial spin labeling to the diagnosis of sudden and transient neurological deficit]

MRI is the gold standard exploration for sudden transient neurological events. If diffusion MRI is negative, there may be a diagnostic doubt between transient ischemic attack and other causes of transient neurological deficit. We illustrate how sequence arterial spin labeling (ASL), which evaluates cerebral perfusion, contributes to the exploration of transient neurological events. An ASL sequence was performed in seven patients with a normal diffusion MRI explored for a transient deficit. Cortical hyperperfusion not systematized to an arterial territory was found in three and hypoperfusion systematized to an arterial territory in four. ASL helped guide early management of these patients.

The psychological impact of predictive genetic testing for Huntington's disease: a systematic review of the literature

Huntington's disease (HD) is a neurodegenerative genetic condition for which a predictive genetic test by mutation analysis has been available since 1993. However, whilst revealing the future presence of the disease, testing may have an adverse psychological impact given that the disease is progressive, incurable and ultimately fatal. This review seeks to systematically explore the psychological impact of genetic testing for individuals undergoing pre-symptomatic mutation analysis. Three databases (Medline, PsycInfo and Scopus) were interrogated for studies utilising standardised measures to assess psychological impact following predictive genetic testing for HD. From 100 papers initially identified, eight articles were eligible for inclusion. Psychological impact of predictive genetic testing was not found to be associated with test result. No detrimental effect of predictive genetic testing on non-carriers was found, although the process was not found to be psychologically neutral. Fluctuation in levels of distress was found over time for carriers and non-carriers alike. Methodological weaknesses of published literature were identified, notably the needs of individuals not requesting genetic testing, as well as inadequate support for individuals registering elevated distress and declining post-test follow-up. Further assessment of these vulnerable individuals is warranted to establish the extent and type of future psychological support.

Automated segmentation and analysis of normal and osteoarthritic knee menisci from magnetic resonance images--data from the Osteoarthritis Initiative

OBJECTIVE

To validate an automatic scheme for the segmentation and quantitative analysis of the medial meniscus (MM) and lateral meniscus (LM) in magnetic resonance (MR) images of the knee.

METHOD

We analysed sagittal water-excited double-echo steady-state MR images of the knee from a subset of the Osteoarthritis Initiative (OAI) cohort. The MM and LM were automatically segmented in the MR images based on a deformable model approach. Quantitative parameters including volume, subluxation and tibial-coverage were automatically calculated for comparison (Wilcoxon tests) between knees with variable radiographic osteoarthritis (rOA), medial and lateral joint space narrowing (mJSN, lJSN) and pain. Automatic segmentations and estimated parameters were evaluated for accuracy using manual delineations of the menisci in 88 pathological knee MR examinations at baseline and 12 months time-points.

RESULTS

The median (95% confidence-interval (CI)) Dice similarity index (DSI) (2 ∗|Auto ∩ Manual|/(|Auto|+|Manual|)∗ 100) between manual and automated segmentations for the MM and LM volumes were 78.3% (75.0-78.7), 83.9% (82.1-83.9) at baseline and 75.3% (72.8-76.9), 83.0% (81.6-83.5) at 12 months. Pearson coefficients between automatic and manual segmentation parameters ranged from r = 0.70 to r = 0.92. MM in rOA/mJSN knees had significantly greater subluxation and smaller tibial-coverage than no-rOA/no-mJSN knees. LM in rOA knees had significantly greater volumes and tibial-coverage than no-rOA knees.

CONCLUSION

Our automated method successfully segmented the menisci in normal and osteoarthritic knee MR images and detected meaningful morphological differences with respect to rOA and joint space narrowing (JSN). Our approach will facilitate analyses of the menisci in prospective MR cohorts such as the OAI for investigations into pathophysiological changes occurring in early osteoarthritis (OA) development.