The effect of messaging on the acceptance of swaps to reduce the energy content of snacks and non-alcoholic drinks ordered in an experimental online workplace canteen: A randomised controlled trial.

Finding effective ways to increase acceptance of lower-energy swaps offered for snacks and non-alcoholic drinks may reduce population energy intake. We examined whether incrementally increasing the tangibility of information accompanying swaps offered increased their acceptance. UK adults (n = 3481) selected a sweet snack, a savoury snack, and a drink in an experimental online canteen after being equally randomised to receive one of four messages when swaps were offered; a control message providing no specific information, a vague calorie message, an exact numeric-calories message or, a physical activity calorie equivalent (PACE). Primary outcomes were the between-group differences in (i) the odds that a sweet, savoury, or drink swap would be accepted and (ii) the energy content for each type of item ordered. Compared with control, the numeric-calories and PACE messages significantly increased the odds of accepting a sweet snack swap. All interventions significantly increased the odds of accepting savoury swaps compared with control. Only the PACE message significantly increased the odds of drink swap acceptance. The numeric-calories and PACE messages significantly reduced the energy content of sweet snacks. All interventions significantly reduced the energy content of savoury snacks. None of the intervention messages significantly reduced the energy content of drinks compared with control. Increasing the tangibility of information provided when offering swaps increased swap acceptance. PACE messaging was the most promising.

Factors related to condomless anal intercourse between men who have sex with men: results from a European bio-behavioural survey.

BACKGROUND: Relationship status is an important factor associated with condomless anal intercourse (CAI) amongst men who have sex with men (MSM). METHODS: A multi-centre bio-behavioural survey with MSM was conducted in 13 European cities (n = 4901) exploring factors associated with CAI via bivariate and multivariate multilevel logistic regression analyses. RESULTS: Likelihood of CAI with casual partners was associated with being 'out' to a majority (AOR = 1.19;95% CI 1,1.42); knowing their HIV status (AOR = 1.86; 95% CI 1.25,2.76); using substances (1-2 AOR = 1.39; 95% CI 1.16,1.63, 2+ AOR = 1.81; 95% CI 1.35,2.42); being older (AOR = 0.98; 95% CI 0.97,0.99); successful sero-communication (AOR = 0.79; 95% CI 0.67,0.94); and, not having a recent HIV test (AOR = 0.78; 95% CI 0.66,0.92). CAI with steady partners was associated with successful sero-communication (AOR = 2.72; 95% CI 2.72,3.66); not having a recent HIV test (AOR = 1.26; 95% CI 1.09,1.46), and; being older (AOR = 0.99; 95% CI 0.98,0.99). CONCLUSIONS: Understandings of partner type and/or relationship status in relation to CAI amongst MSM can potentially play an important role in the development of culturally appropriate HIV/STI prevention and risk-reduction efforts targeting at-risk MSM. Our results speak to the need to consider segmented and tailored public health and health promotion initiatives for MSM with differing CAI behaviours and relationship profiles.

Non-invasive assessment of ICP in children: advances in ultrasound-based techniques.

The assessment of intracranial pressure (ICP) in children with neurological disease remains a cornerstone in their routine management. The quest for a reliable, reproducible and radiation-free non-invasive technique for assessing ICP in children remains somewhat of a holy grail for neurosurgery. This work assesses some of the recent advances in ultrasound-based techniques, addressing both novel processes and modifications aimed at improving the accuracy of existing techniques.

The dominating influence of efficacy above management strategy in the long-term success of alien plant clearing programmes.

Conservation managers are required to make decisions in complex and uncertain contexts. To strengthen the robustness of conservation decisions, several approaches have been proposed to facilitate stakeholder engagement in the setting of conservation objectives and priority actions. While such processes have led to the formulation of several invasive alien plant management strategies to achieve specific objectives, the long-term consequences and trade-offs inherent in these strategies have not been tested. The performance of five of these strategies over 50 years was tested in the protected area context using empirical data from Table Mountain National Park, South Africa. A simulation model based on data for invasive Acacia species in a fire-driven ecosystem, focused on the interaction between strategy performance and clearing efficacy in achieving a management goal or reducing Acacia density to below 1 plant per hectare. At near perfect levels of clearing efficacy, all strategies converged towards reaching the management goal, while at lower efficacy levels the strategies diverged in their ability to achieve desired outcomes. Despite working across the largest area, strategies that focussed on clearing low density invasions, maintained the least area in a maintenance state over time. In contrast, strategies that focussed on a mix of post-fire, low density areas and high altitude areas cleared less area annually, but maintained a much larger area in a maintenance state. At higher levels of efficacy, strategies that return to previously worked areas were more successful than a post-fire strategy. Strategies that focused solely on securing water, performed poorly in maintaining low overall density of aliens. However, the influence of efficacy was significant and substantial and a much larger difference in area reaching the management goal was achieved by varying efficacy than varying strategy. As such, improving quality of work and implementation will have a far greater effect than which areas are prioritized or how this prioritization is done. While acacias are likely to persist in the long-term, improving work quality coupled with correct strategy selection will ensure continued gains in the area under maintenance and improved return on investment over time.

Scenarios for the management of invasive Acacia species in a protected area: Implications of clearing efficacy.

In many protected areas in South Africa, invasive Australian Acacia species pose on-going management challenges, perpetuating high long-term management costs. Due to limited availability of resources, conservation actions need to be prioritised within and across Protected Areas (PA). We draw on comprehensive datasets spanning over 20 years from the Table Mountain National Park to model long-term outcomes of clearing Acacia species at different levels of management clearing efficacy. We test a 50 year outlook based on current and 38 incremental levels of management efficacy, ranging from 5 to 100%, to assess under which scenarios a management goal of reducing Acacia density to below 1 plant per hectare for the 22,671 ha protected area is achieved. With the current clearing resources and maximum clearing efficacy (100% control), it would take between 32 and 42 years to attain the management goal. The modelling revealed two main drivers of Acacia persistence. Firstly, germination of seeds added to the seedbank from standing plants made a significantly larger contribution to future clearing requirements than fire stimulated seed germination or the existing (pre-management) seedbank. Secondly the relationship between the number of hectares and management units that could be treated and the efficacy of the treatment was non-linear. When clearing efficacy was decreased from 100% to the current project minimum target of 80% efficacy, the goal was not achieved in all areas, but the area that reached a density of <1 plant per hectare was significantly reduced to 53% of the PA for the simulated 50 years. Results emphasize the need to differentiate between increasing financial resources and increasing efficacy. While increasing financial resources allows for increased effort, this is of little value for Acacia management in the absence of an increase in clearing efficacy, as low quality implementation perpetuates the need for large budgets over time. Conversely, improving efficacy allows for decreased budget requirements over time, allowing fund re-direction to additional areas of alien species management such as the early detection and rapid control of newly introduced species.

Genetic predisposition to obesity, restrained eating and changes in body weight: a population-based prospective study.

OBJECTIVES: There is no consensus on whether cognitive control over food intake (that is, restrained eating) is helpful, merely ineffective or actually harmful in weight management. We examined the interplay between genetic risk of obesity, restrained eating and changes in body weight and size. METHODS: Participants were Finnish aged 25-74 years who attended the DIetary, Lifestyle and Genetic determinants of Obesity and Metabolic syndrome study at baseline in 2007 and follow-up in 2014. At baseline (n=5024), height, weight and waist circumference (WC) were measured in a health examination and participants self-reported their weight at age 20 years. At follow-up (n=3735), height, weight and WC were based on measured or self-reported information. We calculated 7-year change in body mass index (BMI) and WC and annual weight change from age 20 years to baseline. Three-Factor Eating Questionnaire-R18 was used to assess restrained eating. Genetic risk of obesity was assessed by calculating a polygenic risk score of 97 known BMI-related loci. RESULTS: Cross-lagged autoregressive models indicated that baseline restrained eating was unrelated to 7-year change in BMI (ß=0.00; 95% confidence interval (CI)=-0.01, 0.02). Instead, higher baseline BMI predicted greater 7-year increases in restrained eating (ß=0.08; 95% CI=0.05, 0.11). Similar results were obtained with WC. Polygenic risk score correlated positively with restrained eating and obesity indicators in both study phases, but it did not predict 7-year change in BMI or WC. However, individuals with higher genetic risk of obesity tended to gain more weight from age 20 years to baseline, and this association was more pronounced in unrestrained eaters than in restrained eaters (P=0.038 for interaction). CONCLUSIONS: Our results suggest that restrained eating is a marker for previous weight gain rather than a factor that leads to future weight gain in middle-aged adults. Genetic influences on weight gain from early to middle adulthood may vary according to restrained eating, but this finding needs to be replicated in future studies.

Hydatid disease (Echinococcus) of the central nervous system.

Hydatid disease of the central nervous system is rare and comprises about 2-3% of all the hydatid cyst cases reported in the world. Spinal hydatid is still rare. It is endemic in sheep and cattle-raising regions, seen mainly in Mediterranean countries including Turkey and Syria. Pediatric neurosurgeons in nonendemic countries face a challenge when they are encountered with hydatid cyst of the central nervous system due to lack of awareness and diagnostic dilemmas. It is also a mammoth economic problem in developing countries due to improper hygiene and lack of dedicated veterinary practice. The clinical features are largely nonspecific. However, with the advent of MR imaging, the diagnostic accuracy has increased. Intact removal of the cyst without causing any spillage is the goal and key to cure. In this manuscript, the current literature on hydatid cyst of the brain and spine is reviewed to understand the epidemiological, diagnostic accuracy and advances in therapeutics. A heightened clinical suspicion about hydatid disease, role of MR imaging and improving surgical strategies is discussed. A nationwide prevention of the disease is the ultimate goal.

Infections in the immunocompromised child.

Prevention and management of opportunistic infections in children is particularly relevant in an era demonstrating an increased prevalence of immunocompromising conditions. The presence of an unusual organism which results in serious infection in a child should therefore always raise the consideration of immune compromise. The more common opportunistic infections have become easier to recognize in recent times due to improved awareness and more refined diagnostic testing. Targeted treatment is usually followed by long-term prophylactic medication. The impact of these conditions on patient outcome is of clear significance and certainly warrants further discussion.

A discrete choice experiment to assess people living with HIV's (PLWHIV's) preferences for GP or HIV clinic appointments.

OBJECTIVES: To understand which aspects of general practitioner (GP) and HIV clinic appointments people living with HIV (PLWHIV) most value when seeking advice for new health problems. METHODS: A discrete choice experiment using a convenience sample of people diagnosed with HIV. Participants were recruited from 14 general HIV clinics in the South East of England between December 2014 and April 2015. ORs were calculated using conditional logit (CLOGIT) and latent class models (LCMs). RESULTS: A total of 1106 questionnaires were returned. Most participants were male (85%), white (74%) and were men who have sex with men (69%). The CLOGIT analysis showed people particularly valued shorter appointment waiting times (ORs between 1.52 and 3.62, p<0.001 in all instances). The LCM analysis showed there were two distinct classes, with 59% and 41% of respondents likely to be in each. The first class generally preferred GP to HIV clinic appointments and particularly valued 'being seen quickly'. For example, they had strong preferences for shorter appointment waiting times and longer GP opening hours. People in the second class also valued shorter waiting times, but they had a strong general preference for HIV clinic rather than GP appointments. CONCLUSIONS: PLWHIV value many aspects of care for new health problems, particularly short appointment waiting times. However, they appear split in their general willingness to engage with GPs.

Brief interventions to prevent sexually transmitted infections suitable for in-service use: A systematic review.

BACKGROUND: Sexually transmitted infections (STIs) are more common in young people and men who have sex with men (MSM) and effective in-service interventions are needed. METHODS: A systematic review of randomized controlled trials (RCTs) of waiting-room-delivered, self-delivered and brief healthcare-provider-delivered interventions designed to reduce STIs, increase use of home-based STI testing, or reduce STI-risk behavior was conducted. Six databases were searched between January 2000 and October 2014. RESULTS: 17,916 articles were screened. 23 RCTs of interventions for young people met our inclusion criteria. Significant STI reductions were found in four RCTs of interventions using brief one-to-one counselling (2 RCTs), video (1 RCT) and a STI home-testing kit (1 RCT). Increase in STI test uptake was found in five studies using video (1 RCT), one-to-one counselling (1 RCT), home test kit (2 RCTs) and a web-based intervention (1 RCT). Reduction in STI-risk behavior was found in seven RCTs of interventions using digital online (web-based) and offline (computer software) (3 RCTs), printed materials (1 RCT) and video (3 RCTs). Ten RCTs of interventions for MSM met our inclusion criteria. Three tested for STI reductions but none found significant differences between intervention and control groups. Increased STI test uptake was found in two studies using brief one-to-one counselling (1 RCT) and an online web-based intervention (1 RCT). Reduction in STI-risk behavior was found in six studies using digital online (web-based) interventions (4 RCTs) and brief one-to-one counselling (2 RCTs). CONCLUSION: A small number of interventions which could be used, or adapted for use, in sexual health clinics were found to be effective in reducing STIs among young people and in promoting self-reported STI-risk behavior change in MSM.

Energy and nutrient intakes of young children in the UK: findings from the Gemini twin cohort.

Data on the diets of young children in the UK are limited, despite growing evidence of the importance of early diet for long-term health. We used the largest contemporary dietary data set to describe the intake of 21-month-old children in the UK. Parents of 2336 children aged 21 months from the UK Gemini twin cohort completed 3-d diet diaries in 2008/2009. Family background information was obtained from questionnaires completed 8 months after birth. Mean total daily intakes of energy, macronutrients (g and %E) and micronutrients from food and beverages, including and excluding supplements, were derived. Comparisons with UK dietary reference values (DRV) were made using t tests and general linear regression models, respectively. Daily energy intake (kJ), protein (g) and most micronutrients exceeded DRV, except for vitamin D and Fe, where 96 or 84 % and 70 or 6 % of children did not achieve the reference nutrient intake or lower reference nutrient intake (LRNI), respectively, even with supplementation. These findings reflect similar observations in the smaller sample of children aged 18-36 months in the National Diet and Nutrition Survey. At a population level, young children in the UK are exceeding recommended daily intakes of energy and protein, potentially increasing their risk of obesity. The majority of children are not meeting the LRNI for vitamin D, largely reflecting inadequate use of the supplements recommended at this age. Parents may need more guidance on how to achieve healthy energy and nutrient intakes for young children.

Non-invasive intracranial pressure assessment.

Assessing intracranial pressure (ICP) remains a cornerstone in neurosurgical care. Invasive techniques for monitoring ICP remain the gold standard. The need for a reliable, safe and reproducible technique to non-invasively assess ICP in the context of early screening and in the neurocritical care environment is obvious. Numerous techniques have been described with several novel advances. While none of the currently available techniques appear independently accurate enough to quantify raised ICP, there is some promising work being undertaken.

The relationship between transorbital ultrasound measurement of the optic nerve sheath diameter (ONSD) and invasively measured ICP in children. : Part II: age-related ONSD cut-off values and patency of the anterior fontanelle.

PURPOSE: To analyse the diagnostic accuracy of age-related optic nerve sheath diameter (ONSD) cut-off values in children for detecting raised intracranial pressure (ICP) and to assess the benefit of using patency of the anterior fontanelle in describing a different set of cut-off values. METHODS: The ONSD measurement was performed prior to invasive ICP measurement in children under general anesthesia. The diagnostic accuracy of the ONSD measurement was compared to ICP at thresholds of 20, 15, 10, and 5 mmHg. This was further analysed in children above and below the age of 1 year, with a subgroup analysis of age at 4 years, and assessment of the anterior fontanelle (AF) as a reliable physiological marker in part II of this study. RESULTS: Data from 174 children were analysed. In children ≤1 year old, the ONSD measurement with the best diagnostic accuracy for detecting ICP ≥ 20 mmHg was 5.16 mm, compared to 5.75 mm in children >1 year old (p < 0.001). In addition, patency of the anterior fontanelle (AF) was found to be a useful clinical marker for defining different ONSD cut-off values at ICP thresholds of 20, 15, 10 and 5 mmHg. CONCLUSION: Transorbital ultrasound measurement of the ONSD is a reliable non-invasive marker of ICP particularly at higher thresholds of 20 and 15 mmHg. Patency of the AF is a useful clinical marker for defining different ONSD cut-off values in children.

The relationship between transorbital ultrasound measurement of the optic nerve sheath diameter (ONSD) and invasively measured ICP in children : Part I: repeatability, observer variability and general analysis.

PURPOSE: The aim of this study was to investigate the relationship between optic nerve sheath diameter (ONSD) measurement and invasively measured intracranial pressure (ICP) in children. METHODS: ONSD measurement was performed prior to invasive measurement of ICP. The mean binocular ONSD measurement was compared to the ICP reading. Physiological variables including systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse rate, temperature, respiratory rate and end tidal carbon dioxide (ETCO2) level were recorded at the time of ONSD measurement. Diagnostic accuracy analysis was performed at various ICP thresholds and  repeatability, intra- and inter-observer variability, correlation between measurements in different imaging planes as well the relationship over the entire patient cohort were examined in part I of this study. RESULTS: Data from 174 patients were analysed. Repeatability and intra-observer variability were excellent (α = 0.97-0.99). Testing for inter-observer variability revealed good correlation (r = 0.89, p < 0.001). Imaging in the sagittal plane demonstrated a slightly better correlation with ICP (r = 0.66, p < 0.001). The ONSD measurement with the best diagnostic accuracy for detecting an ICP ≥ 20 mmHg over the entire patient cohort was 5.5 mm, sensitivity 93.2 %, specificity 74 % and odds ratio (OR) of 39.3. CONCLUSION: Transorbital ultrasound measurement of the OSND is a reliable and reproducible technique, demonstrating a good relationship with ICP and high diagnostic accuracy for detecting raised ICP.

Which aspects of health care are most valued by people living with HIV in high-income countries? A systematic review.

BACKGROUND: Increasing numbers of people with HIV are living into older age and experiencing comorbidities. The development of new models of care to meet the needs of this population is now a priority. It is important that the views and preferences of patients inform the development of services in order to maintain high levels of patient satisfaction and engagement. The aim of this systematic review was to determine which aspects of healthcare are particularly valued by people living with HIV. METHODS: We searched electronic databases and reference lists of relevant articles. The search strategy was developed to identify articles reporting on HIV positive patients' perceptions, evaluations or experiences of healthcare services and factors associated with satisfaction with care. Peer-reviewed papers and conference abstracts were included if the study reported on aspects of health care that were valued by people living with HIV, data were collected during the era of combination therapy (from 1996 onwards), and the paper was published in English. A thematic approach to data synthesis was used. RESULTS: Twenty-three studies met the inclusion criteria. Studies used both qualitative and quantitative methods. Six studies specifically reported on relative importance to patients of different aspects of care. The valued aspects of care identified were grouped into seven themes. These highlighted the importance to patients of: a good health care professional-patient relationship, HIV specialist knowledge, continuity of care, ease of access to services, access to high quality information and support, effective co-ordination between HIV specialists and other healthcare professionals, and involvement in decisions about treatment and care. We were unable to determine the relative importance to patients of different aspects of care because of methodological differences between the studies. CONCLUSIONS: This review identified several attributes of healthcare that are valued by people living with HIV, many of which would be relevant to any future reconfiguration of services to meet the needs of an ageing population. Further research is required to determine the relative importance to patients of different aspects of care.

Nighttime sleep duration and hedonic eating in childhood.

BACKGROUND: Higher food intake is implicated in the elevated risk of obesity associated with shorter sleep in children, but the mechanisms driving higher intake are uncertain. Research in adults suggests that acute sleep deprivation affects brain reward systems, which increases responsiveness to palatable foods. However, there have been few studies addressing habitual sleep duration, and few in children, among whom the strongest associations with body mass index (BMI) are seen. OBJECTIVE: The objective of this study is to test the hypothesis that shorter-sleeping children are more food responsive and explore the mediation of the relationship between sleep and weight by food responsiveness (FR). METHODS: Participants were families from Gemini, a UK twin birth cohort, who had provided complete information on their children's sleep and appetite at age 5 years (n=1008). One child from each twin pair was randomly selected for analyses. Nighttime sleep duration was calculated from parent-reported bedtime and wake time, and categorised as shorter, adequate or longer according to age-specific reference values. FR was assessed with the Child Eating Behaviour Questionnaire. BMI s.d. scores (BMI-SDS) were calculated from parent-measured heights and weights using the UK 1990 reference data and were available for 494 children. RESULTS: There was a significant linear association between shorter sleep and higher FR at age 5 years (P for linear trend=0.032), which was maintained after adjusting for age, sex, birth weight, maternal education and BMI-SDS. In the subset with BMI data at age 5 years, shorter sleep was associated with higher BMI-SDS (P=0.026) as expected. Testing for mediation by adding FR to the model attenuated the linear relationship to borderline significance (P=0.049), suggesting partial mediation. CONCLUSIONS: Shorter sleep in childhood is associated with higher FR, which may partly explain the association between shorter sleep and adiposity in childhood.

Change in optic nerve sheath diameter as a radiological marker of outcome from endoscopic third ventriculostomy in children.

PURPOSE: The purpose of this study was to investigate the value of the change in optic nerve sheath diameter (ONSD) as a radiological marker of endoscopic third ventriculostomy (ETV) outcome in children. METHODS: Magnetic resonance imaging (MRI) scans of patients on whom ETVs were performed between the periods of January 2009 and June 2013 were reviewed. ONSD measurements on pre- and post-operative images were performed by two blinded observers, and the relationship between the change in these measurements and outcome from ETV were investigated. These findings were then also compared to conventional imaging features associated with ETV outcome. RESULTS: MRI scans of 24 patients were adequate to measure the ONSD pre- and post-operatively. In patients with successful ETV (n = 19), the mean change in ONSD was 0.73 mm and in patients with a failed ETV (n = 5), the mean change in ONSD was 0.18 mm (p = 0.0007). A change in ONSD of 7.5 % of the initial measurement demonstrated a sensitivity of 92.9 % and a sensitivity of 85.7 % for ETV outcome (area under the receiver operating characteristic curve (AUROC) = 0.96). CONCLUSION: Change in ONSD is a useful radiological marker of ETV outcome and may be used in combination with conventional radiological parameters to aid decision-making in this difficult group of patients.

The role and value of conservation agency research.

Governments charge their conservation agencies to safeguard biodiversity through protected areas and threat mitigation. Increasingly, conservation management and policy need to be supported by rigorous evidence provided by science. As such, institutional arrangements should consider and enable effective scientific research and information dissemination. What role can in-house agency research play in responding to this challenge? We examined the research capabilities of three conservation agencies from Australia, South Africa, and United States. Seven indicators were used to characterize the reliability and relevance of agency research. We found similarities among agencies in their patterns of peer-reviewed publication, cultures of research collaboration, and tendencies to align research with organizational objectives. Among the many and diverse activities that constitute the role of a contemporary agency researcher, we emphasize two key research dimensions: reliability, achieved through peer-reviewed research output, and relevance, achieved through active stakeholder engagement. Amid increasingly challenging realities for conservation of ecosystems, agency science functions are vital to providing the evidence base required for effective management and policy development.

Associations between infant feeding and the size, tempo and velocity of infant weight gain: SITAR analysis of the Gemini twin birth cohort.

OBJECTIVE: Infant growth trajectories, in terms of size, tempo and velocity, may programme lifelong obesity risk. Timing of breastfeeding cessation and weaning are both implicated in rapid infant growth; we examined the association of both simultaneously with a range of growth parameters. DESIGN: Longitudinal population-based twin birth cohort. SUBJECTS: The Gemini cohort provided data on 4680 UK infants with a median of 10 (interquartile range=8-15) weight measurements between birth and a median of 6.5 months. Age at breastfeeding cessation and weaning were reported by parents at mean age 8.2 months (s.d.=2.2, range=4-20). Growth trajectories were modelled using SuperImposition by Translation And Rotation (SITAR) to generate three descriptors of individual growth relative to the average trajectory: size (grams), tempo (weeks, indicating the timing of the peak growth rate) and velocity (% difference from average, reflecting mean growth rate). Complex-samples general linear models adjusting for family clustering and confounders examined associations between infant feeding and SITAR parameters. RESULTS: Longer breastfeeding (>4 months vs never) was independently associated with lower growth velocity by 6.8% (s.e.=1.3%) and delayed growth tempo by 1.0 (s.e.=0.2 weeks), but not with smaller size. Later weaning (⩾6 months vs <4 months) was independently associated with lower growth velocity by 4.9% (s.e.=1.1%) and smaller size by 102 g (s.e.=25 g). CONCLUSIONS: Infants breastfed for longer grew slower for longer after birth (later peak growth rate) but were no different in size, while infants weaned later grew slower overall and were smaller but the timing of peak growth did not differ. Slower trajectories with a delayed peak in growth may have beneficial implications for programming later obesity risk. Replication in cohorts with longer follow-up, alternative confounding structures or randomised controlled trials are required to confirm the long-term effects and directionality, and to rule out residual confounding.

Sleep and energy intake in early childhood.

BACKGROUND AND OBJECTIVES: Shorter sleep is associated with higher weight in children, but little is known about the mechanisms. The aim of this study was to test the hypothesis that shorter sleep was associated with higher energy intake in early childhood. METHODS: Participants were 1303 families from the Gemini twin birth cohort. Sleep duration was measured using the Brief Infant Sleep Questionnaire when the children were 16 months old. Total energy intake (kcal per day) and grams per day of fat, carbohydrate and protein were derived from 3-day diet diaries completed by parents when children were 21 months old. RESULTS: Shorter nighttime sleep was associated with higher total energy intake (P for linear trend=0.005). Children sleeping <10 h consumed around 50 kcal per day more than those sleeping 11-<12 h a night (the optimal sleep duration for children of this age). Differences in energy intake were maintained after adjustment for confounders. As a percentage of total energy intake, there were no significant differences in macronutrient intake by sleep duration. The association between sleep and weight was not significant at this age (P=0.13). CONCLUSIONS: This study provides the first evidence that shorter nighttime sleep duration has a linear association with higher energy intake early in life. That the effect is observed before emergence of associations between sleep and weight indicates that differences in energy intake may be a mechanism through which sleep influences weight gain.