What makes nature-based interventions for mental health successful?

Nature-based interventions for mental health are beginning to become more common in the UK. The evidence for their usefulness is building. Taking the 'A Dose of Nature' project in the south-west as an example, factors for making such interventions a success are described.

Throughout the UK there is increasing interest in the relationship between natural outdoor spaces and human health and well-being (Bragg & Leck, 2017). Some of this work involves using nature as the setting for health interventions, for example outdoor exercise programmes. Other initiatives position nature explicitly as the source of betterment, for example ecotherapy programmes. In all examples, nature is understood to hold therapeutic potential, and the relationship between experiencing nature and being healthier is the focus.

In particular, there has been a surge of interest in nature-based interventions for mental health problems, as there is now strong evidence that people with good access to natural environments are more likely to have better mental well-being (Mitchell et al, 2015; Lovell, 2016).

While many countries have inadequate community mental healthcare provision, the resources needed for nature-based interventions for mental health can be found in every country. The potential opportunities for capitalising on this service delivery model are vast. This paper: outlines the evidence for nature-based interventions for mental health and well-being; describes how one service, ‘A Dose of Nature’, was developed and delivered; considers likely patient benefits from this sort of intervention; and outlines key challenges and factors that ensure success.

Evidence summary

Broadly, the evidence for a link between mental health and engagement with, access to and interventions within nature is substantial; the findings are of variable reliability but there is a consistent positive trend (Lovell, 2016). Some of the most robust evidence relates to general well-being, such as the evaluation of the UK’s Walking for Health programme (Marselle et al, 2014). These gains in well-being may accrue via improvements in the following factors: affect and cognition (Bratman et al, 2015); mood (van den Berg et al, 2003); attention, anger, fatigue and sadness (Bowler et al, 2010; Thompson Coon et al, 2011).

Evidence for specific mental health conditions is less extensive, although there are studies showing a positive impact of being in natural environments upon depression (Berman et al, 2008), anxiety (van den Berg & Clusters, 2011) and, by improving concentration, upon attention-deficit hyperactivity disorder (van den Berg & van den Berg, 2011).

What has been missing from these accounts to date are detailed case studies of nature-based interventions, to shed light upon questions concerning dose, replicability (at scale and in different environments), access, cost-effectiveness, and the potential to address mental health inequalities. These are complex issues, and A Dose of Nature was set up to begin the process of providing the kind of service that can support such studies.

A Dose of Nature

From spring 2015 to autumn 2016, eight different nature-based interventions for health and wellbeing were run in Bristol, Exeter and locations throughout Cornwall, all in the south-west of the UK. The work began with a lengthy process of engagement with doctors, mental health professionals, patients, environmental managers and those able to run interventions. It allowed for a model to slowly emerge of what kind of nature-based intervention was both practicable and attractive to all.

The interventions had common features. Each was a partnership between health staff working in primary care (mostly doctors in general practice, as well as practice nurses), local organisations owning and/or managing natural assets, and practitioners able to run the intervention itself. The interventions ran for 12 weeks and involved small groups of participants (typically four to ten). Each weekly session was 2–3 hours long. Simple well-being questionnaires were completed before and after the course. The time was spent outside, in places defined as rich in natural beauty and/or biodiversity. The courses were free to participants.

The majority of participants were referred to the courses, but some groups also included self-referred participants. While all of the groups involved some sort of physical activity and some sort of activity focusing on engaging with natural phenomena, this allowed for a variations in the details of delivery. Some groups focused on walking, while some had a silent or meditative element. Some involved conservation, such as managing woods. Another major source of difference within the overall programme was the natural environment itself, which inevitably varies across locations. Some were based in woodland areas, some in coastal zones, some in areas of countryside dominated by agriculture and others in greenspace in and around urban settlements.

At the beginning of the programme the general objective, following the logic of knowledge exchange work, was to increase interest in the topic in all relevant groups, and to build capacity in the system to support further work and identify subsequent research questions. As a result, at first, no specific mental health diagnosis was the focus of the work; doctors were able to make a referral simply because they felt that such an activity would be good for that individual. At this stage, it was not yet the intention to replace existing clinical care options (e.g. the prescription of antidepressants or a referral to community mental health services), but only to increase choice, for both patients and referrers. As the project developed, the referral process tightened to focus on patients with a diagnosis of mild to moderate depression and/or anxiety. In the final patient cohorts, all referrals were based on a diagnosis of depression, from mild to severe (i.e. referrals from both primary care and clinical psychiatrists within secondary care).

Benefits

The impacts on patient-participants involved in A Dose of Nature have been numerous. These include mental health gains as well as social and financial benefits. The project has seen 64 patient referrals, from which have resulted:

48 patients completing a programme of 10–12 weeks

an average cost per patient of £317.33

an average increase of 69% in self-reported well-being (using the Warwick and Edinburgh Mental Well-Being Scale)

two new self-organised support groups

at least four patients signing up for further training and/or volunteering activities

at least two patients reducing, or expecting to reduce, prescribed medicines.

We have measured considerable improvements in mental well-being. Patients have described improvements in mood and reductions in anxiety. Typical statements from service users were as follows:

It’s been a fantastic experience for me and I do hope in the future that instead of being a pilot scheme this will go on to become a more permanent thing. (Patient, Stennack Health Centre)

I suffer with mental health issues and it has helped me enormously; it’s kind of like a breath of fresh air in a way. You see things differently and you forget your worries for the day, which is good. Talking to others who have gone through similar experiences such as myself has also helped me very much with my mental health. All round it’s been a definite benefit. (Patient, Bodriggy Surgery)

Participants have also reported improvements in their social skills: greater confidence in social settings; improved sense of individual worth and of agency; learning new skills and knowledge; and the formation of new friendships. Clearly, the social dimension of a nature-based intervention group is important in terms of group dynamics and thus in terms of effect upon outcomes. A question for the future is to what extent the social, as opposed to the natural environmental, dimension can be teased out and examined in terms of intervention efficacy. In the meantime, however, it should be noted that with this kind of intervention, a ‘social prescription’, benefits can deepen over time; for example, a number of self-organised groups have continued to meet after the 12-week ‘official’ intervention ended.

Referrers have also responded positively to the pilots; all 12 of the referrers into the scheme stated that they saw benefits to their patients and wished to continue to be able to send people to the service, or a similar extension.

Case studies have shown that participating in a nature-based intervention can result in personal financial gains, both from avoiding costs (e.g. for prescriptions) and from entering the employment market (Vardakoulias, 2013). The experience of A Dose of Nature seems to bear this out, as participants have gained new skills, taken up voluntary positions and expressed confidence in being able to reduce their medication in due course.

As well as individual patient benefits, it is worth considering the larger potential impact on health economics. The cost of mental health problems in the UK is estimated at £70–£100 billion per annum, or 4.5% of gross domestic product (Bowler et al, 2010). Although the analysis for A Dose of Nature has not been carried out, Mind’s ‘Ecominds’ programme – a more extensive programme of similar and varied nature-based interventions – resulted in an average saving per participant of £7082, via reduced costs to the National Health Service, benefits reductions and increased tax contributions (Vardakoulias, 2013).

Key factors in developing successful nature-based interventions

The experience of developing and delivering A Dose of Nature has identified a number of key factors affecting success.

Engagement

Unless all key groups are brought together to discuss the intervention at an early stage, then the work will likely fail. All participants – patients, doctors, those running the groups and those owning and managing the land that is being used for this purpose – must have confidence in the programme and in each other. This takes time. It requires a coordinator who is able to speak (at least) two different ‘languages’: the language of healthcare and practice; and the language of nature and environmental engagement.

Flexibility

The issue of language is important because as the project develops it is necessary to jointly co-design, co-own and co-deliver the intervention. Health professionals are liable to see the work largely or wholly in terms of health benefit to patients and reduced health costs. There is an inherent risk of devaluing the work if this happens. Similarly, conservation or environmental management partners might see the work only in terms of potential ecological gain, or even as a way of boosting their income. Again, this can derail the project. It is important to identify mutual benefits, questions that both sides of the equation are interested in answering, and practical solutions that meet everyone’s needs (e.g. timings, activities, dates, bad-weather options and transportation).

Managing the introduction

How does one best take a patient from a clinical setting to a non-clinical, social one? How does one minimise the rate at which patients fail to engage, or fail to complete the course? The initial referral, the introduction to the idea, is vital. Designing a nature-based intervention requires a lot of thought about the words and images used in printed material, whether the intervention organiser will contact the patient directly or not, and whether a third-party referral coordinator will be used. The aim should be to put the patient-participant at the heart of this process, so that it is clear from the start that the work is focused on meeting their needs.

At the same time, there is a risk that patients expecting traditional medical treatment might feel they are being offered something that is a cheaper, second-best alternative; the referral process needs to emphasise that a nature-based intervention – or any form of social prescription – is a high-quality option, run by professionals with adequate training and oversight, but that it is additional to, not instead of, clinical care. A social prescription is not a clinical intervention.

Practitioner skills

People leading nature-on-referral schemes need: to be able to explain, describe or otherwise animate nature so that it is made relevant and engaging to participants; to be able to manage simple group dynamics; and to pass a set of locally determined criteria (typically including insurance, driving skills, criminal background checks and first-aid certification).

The interventions are run by local groups rooted in the community, delivering non-clinical work. Advanced psychological or nursing backgrounds are not necessary: practitioners come from a variety of backgrounds – clinical but also psychotherapy, education or community engagement.

Timings

For some of the A Dose of Nature interventions, participants had to wait until a sufficient number had been referred to form a group, and this could mean waiting times of up to 6 weeks. Other groups used a rolling model, with participants able to join and leave at different times. The choice of format was up to the practitioners, the referrer and the patients, but it can be noted that season and weather were largely irrelevant factors. In fact, some patients reported the greatest positive impact against feelings of depression as occurring during poor weather as the winter season became more advanced.

Applicability

As has already been said, the key ingredients for nature-based interventions are common: a health system that is struggling under the burden of mental ill-health; a local natural environment of some description (nature-based interventions can occur in urban parks, farms, gardens or any common green space, as well as in relatively ‘wild’ spaces set aside for nature); and a community willing to work together to try new ideas and help each other. There is no evidence that a nature-on-referral intervention such as the one described in this paper has any greater or lesser impact whether it is developed in an urban or in a rural setting. With depression being a global pandemic, and with some form of ‘green’ or natural space being accessible even in the world’s biggest cities, at the very least the potential of such an approach is worth exploring internationally.

Next steps

The work done in A Dose of Nature is being carried forwards in two different but related ways. First, it will help inform an ongoing realist review (Husk et al, 2016). This is a type of systematic review that will look at the different ways in which referrals occur within social prescribing initiatives, and at what works, for whom and in what circumstances. As nature-based interventions develop, this is an important area to address for the whole process to be successful.

Second, the author is currently working with Cornwall Council, alongside the local Health and Well-Being Board, the Local Nature Partnership and the Local Economic Partnership, to deliver a project (funded by the Natural Environment Research Council) that seeks to expand and standardise the referral of patients to nature-based interventions, and make them available across the entire county. More information can be found at http://www.adoseofnature.net.