Green space and loneliness: a systematic review with theoretical and methodological guidance for future research

Abstract

Urban greening may help to reduce the population health impacts of loneliness and its concomitants, such as hopelessness and despair. However, the literature lacks both a critical appraisal of extant evidence and a conceptual model to explain how green space would work as a structural intervention. Both are needed to guide decision making and further research. We conducted a systematic review of quantitative studies testing associations between green space and loneliness, searching seven databases. Twenty two studies were identified by 25/01/2022. Most of the studies were conducted in high-income countries and fifteen (68%) had cross-sectional designs. Green space was measured inconsistently using either objective or subjective indicators. Few studies examined specific green space types or qualities. The majority of studies measured general loneliness (e.g. using the UCLA loneliness scale). Different types of loneliness (social, emotional, existential) were not analysed. Of 132 associations, 88 (66.6%) indicated potential protection from green space against loneliness, with 44 (33.3%) reaching statistical significance (p<0.05). We integrated these findings with evidence from qualitative studies to elaborate and extend the existing pathway domain model linking green space and health. These elaborations and extensions acknowledge the following: (a) different types of green space have implications for different types of loneliness; (b) multilevel circumstances influence the likelihood a person will benefit or suffer harm from green space; (c) personal, relational, and collective processes operate within different domains of pathways linking green space with loneliness and its concomitants; (d) loneliness and its concomitants are explicitly positioned as mediators within the broader causal system that links green space with health and wellbeing. This review and model provide guidance for decision making and further epidemiological research on green space and loneliness.

Nature exposure and mental health during the COVID-19 pandemic: A Navigation Guide systematic review with meta-analysis

“…These effects also reinforce pre-COVID-19 research that observed similar health outcomes in more general contexts (Lackey et al, 2021). Building on a model proposed by (Markevych et al, 2017), (Astell-Burt et al, 2022) focused on loneliness, which many people may experience in times of social distancing, to describe how experiences and opportunities in natural areas interact with individual and place-based differences to impact health and wellbeing through four broad domains: building capacities, restoring capacities, reducing harm, and causing harm. These pathways are consistent with theoretical frameworks explaining the restorative benefits of natural environments, including attention restoration (R. Kaplan & Kaplan, 1989; S. Kaplan, 1995) and stress reduction theories (Ulrich et al, 1991).…”

“…This study joins a growing set of reviews and meta-analyses in the broader field of research examining links between nature exposure and health that are constrained from drawing concrete conclusions due to bias and quality concerns (e.g., (Astell-Burt et al, 2022;Zare Sakhvidi et al, 2022;Zhang et al, 2021). Even minor adjustments, such as improving the consistency of nature exposure's instrumentation, providing clear estimates of effects and effect sizes, and controlling for confounding could substantially reduce bias.…”

Need and Interest in Nature Prescriptions to Protect Cardiovascular and Mental Health: A Nationally-Representative Study With Insights for Future Randomised Trials

“…For instance, recent qualitative research [32] indicates high willingness to promote nature prescriptions among mental health clinicians, but also concerns regarding multiple barriers that may challenge implementation of nature prescriptions in people living with mental illness. One such barrier might be a lack of physical access or transport to a nature space that feels safe and with qualities that attend to an individual's preferred routines [3,9,16]. A nature prescription that applies social pressure on a person to visit a space in which they feel out of place or unsafe may be a source of distress rather than restoration [33].…”

“…Contact with nature mitigates harms (e.g. by regulating air quality [5]), restores depleted cognitive capacities [6,7], alleviates stress [8], reduces loneliness [9][10][11] and encourages regular health behaviours such as physical activity [12,13]. Meta-analyses indicate interventions that enable people to spend more time in nature increase levels of physical activity and lower risks of depression, anxiety, and high blood pressure [14], providing a compelling and urgent case to support harnessing nature in health care [15,16].…”

Nature Rx: Nature prescribing in general practice

“…1,10 Emerging evidence indicates that these psychological benefits may be closely entwined with restorative processes that ameliorate feelings of chronic loneliness. 13 Only one study has been conducted in general practice in Australia, in Adelaide. 14 This study involved an 8-week facilitated nature prescribing trial, first mapping green spaces locally, followed by the recruitment of 30 general practitioners (GPs) who recruited participants with chronic disease (mild-moderate diabetes or depression/anxiety).…”