Development of a digital intervention to promote healthy growth during the first 2 years of life

Context
According to the National Childhood Measurement Programme, more than 1/5 children in England have developed overweight or obesity by the time they start primary school. Children living in the most deprived areas are more than twice as likely to be affected by obesity as those living in the least deprived areas. Children with obesity are over five times more likely to have obesity as adults, and are at increased risk of developing asthma, type 2 diabetes, cancer, heart and liver disease, and associated mental health problems - even from childhood. Obesity costs the NHS more than £5.1 billion, and employers approximately £7 billion.

Once developed, obesity is difficult to reverse, and a substantial body of evidence has established that rapid infant weight gain (from birth to 2 years) is causally linked to future obesity. Infancy is therefore a key window of opportunity for obesity prevention. In high incomes countries, rapid infant weight gain is common, especially among formula fed infants, with large studies estimating up to 40% of healthy full-term infants experiencing it. Managing rapid infant weight gain is challenging for parents: many infants have an avid appetite and a preference for sweet tasting foods, predisposing them to excessive milk and food intake; many parents use feeding to calm their unsettled infant or promote longer sleep duration; and parents and healthcare professionals often view rapid weight gain as healthy or advantageous. Three behavioural feeding interventions have succeeded in changing target behaviours among infants during the period of exclusive milk-feeding and/or weaning (starting solid foods): BABY MILK (UK), NOURISH (Australia) and INSIGHT (US). However, all were delivered face-to-face, with additional written materials and phone support. Due to increasing workload pressures on healthcare providers, there is a need for a behavioural intervention that does not require face-to-face delivery, and is cost effective and sustainable. A digital intervention would support parents who are increasingly being signposted to self-help materials, and would allow the intervention to be scalable to the population level. 'Baby Buddy' is the UK charity Best Beginnings' free, multi-award winning app, which provides information and tools to support parents in infant care. It has been downloaded >200,000 times (~1200 downloads per week), is accredited by the DHSC (and a large number of other organisations), available for download in the NHS apps library, and has a very wide reach with younger and more deprived mothers over-represented, making it an ideal platform for such an intervention.

Aims and objectives
In collaboration with Best Beginnings, we will adapt BABY MILK, NOURISH and INSIGHT for digital delivery in the UK, via Baby Buddy. Currently, Baby Buddy has very limited information about managing the key behaviours related to infant weight gain (milk-feeding, weaning, sleep, crying, activity, and understanding healthy weight gain). We will develop new interactive information on these topics, focusing on the first 2 years of infancy, based on the best available evidence of what works. We will work with Best Beginnings' network of parents and health professionals to review and advise on all stages of the intervention development, to ensure the content is user-friendly, engaging, persuasive and salient.

Potential applications and benefits
This digital intervention will provide parents with much-needed support on managing key behaviours related to infant weight gain, and will also offer a source of information for healthcare professionals to signpost families to, in order to free up their time. An effective and scalable intervention that optimises infant growth and nutrition has the potential to be rolled out on a population level and reduce the health and economic burdens of obesity both in childhood and adulthood.

The 2018 SACN report 'Feeding in the First Year of Life' highlighted excess energy intake and weight gain in infants as a concern, as this is an established risk factor for obesity. Modifying energy intake and weight gain is challenging because many infants have inherent tendencies towards higher than optimal appetite and a preference for sweet tasting foods. Furthermore, many parents use feeding to calm their unsettled infant or promote longer sleep duration, and may view rapid weight gain as healthy or advantageous. 3 interventions have succeeded in changing target behaviours among infants during exclusive milk-feeding and/or complementary feeding - BABY MILK (UK), NOURISH (Australia) and INSIGHT (US) - but all were delivered face-to-face. Due to increasing workload pressures on healthcare providers, there is a need for a behavioural intervention that does not require staff time, is cost effective, sustainable, widely accessible and scalable to the population level. We will use a person-based, evidence-based approach to develop a digital intervention to encourage and support parents to feed their infants appropriately to promote healthy growth from birth to 2 years. The intervention will target behaviours associated with infant weight gain (milk-feeding, complementary feeding, sleep, crying and activity), and will adapt BABY MILK, NOURISH and INSIGHT for digital delivery. Feeding is an emotive subject for parents, and variation in infant traits pose unique challenges; hence the intervention will be developed with parents using a person-based approach. This goes beyond assessments of acceptability, usability and satisfaction; the intervention will be modified during the process to make it more persuasive, feasible, and salient in order to enhance initial and sustained engagement by users. It will be designed as new content for a widely-used app (Baby Buddy) and will include information appropriate to the infant's age and developmental stage, and enable interaction.

The development of this intervention has the potential to benefit several groups:

Families with infants and young children, including those from disadvantaged backgrounds

This intervention will provide young families with freely available, evidence-based information and advice about key behaviours during the first two years of their child's life that will help to optimise their infant's weight gain, and reduce their risk of future obesity and its associated health problems. Baby Buddy is already very widely used (>200,000 downloads; ~1200 downloads/week) and has an over-representation of younger mothers from disadvantaged backgrounds; developing the intervention on this app will therefore help to ensure that it reaches the children at highest risk of obesity, and will help to reduce social inequalities in health. A recent survey undertaken by Best Beginnings highlighted that parents wanted advice on key components targeted in this intervention (milk-feeding, complementary feeding, sleeping and crying), and the person-based approach to developing the intervention will ensure that the final content is acceptable, engaging, salient and persuasive, and that the advice offered is feasible to follow.

The NHS, healthcare professionals and public health practitioners working with young families

The NHS currently spends over £5.1 billion on obesity-related health costs. An evidence-based early life obesity prevention intervention therefore has the potential for enormous cost saving to the NHS. Due to scarce resources and increasing pressure on the workloads of healthcare providers, there is a need for interventions that do not require face-to-face contact, are cost effective, sustainable, and scalable to the population level. An evidence-based digital intervention that supports parents in optimising their infant's early growth and nutrition provides a valuable resource that could be rolled out at a population level at low cost. Baby Buddy is accredited by the DHSC (and a large number of other organisations) and available for download within the NHS library; developing the intervention within this app will provide a free, easy-to-access self-help resource for health professionals to signpost parents to.

Policymakers

The 2018 SACN report 'Feeding in the First Year of Life' highlighted the high prevalence of excess energy intake and infant overweight as a concern. Currently there are no UK guidelines for how to prevent or manage rapid infant weight gain. Evidence-based interventions of behavioural techniques that succeed in preventing or managing rapid infant weight gain are needed to develop guidelines. The development of this intervention will therefore contribute importantly to the evidence base that is needed.

Charities and not-for-profit organisations such as Best Beginnings

Following their recent survey of the topics that parents reported they want advice about during the early years, Best Beginnings have committed to develop new evidence-based content on milk-feeding, introducing solid foods, sleep and crying for Baby Buddy. We will develop this in collaboration with them. The intervention will be publicly available via Baby Buddy for other not-for-profit organisations to signpost young families to.

The broader economy

McKinsey estimates the cost of obesity to employers in the UK to be £7 billion. Developing an obesity prevention intervention with the potential to reduce adult obesity could therefore benefit employers in the future. In addition, UK taxpayers will benefit from the development of a low cost digital intervention that can replace more intensive face-to-face interventions, which require substantial public funds.