UCSF

Introduction

Exposure to nature may reduce stress in low-income parents. This prospective randomized trial compares the effect of a physician's counseling about nature with or without facilitated group outings on stress and other outcomes among low-income parents.

Materials and methods

Parents of patients aged 4-18 years at a clinic serving low-income families were randomized to a supported park prescription versus independent park prescription in a 2:1 ratio. Parents in both groups received physician counseling about nature, maps of local parks, a journal, and pedometer. The supported group received additional phone and text reminders to attend three weekly family nature outings with free transportation, food, and programming. Outcomes measured in parents at baseline, one month and three months post-enrollment included: stress (using the 40-point Perceived Stress Scale [PSS10]); park visits per week (self-report and journaling); loneliness (modified UCLA-Loneliness Scale); physical activity (self-report, journaling, pedometry); physiologic stress (salivary cortisol); and nature affinity (validated scale).

Results

We enrolled 78 parents, 50 in the supported and 28 in the independent group. One-month follow-up was available for 60 (77%) participants and three-month follow up for 65 (83%). Overall stress decreased by 1.71 points (95% CI, -3.15, -0.26). The improvement in stress did not differ significantly by group assignment, although the independent group had more park visits per week (mean difference 1.75; 95% CI [0.46, 3.04], p = 0.0085). In multivariable analysis, each unit increase in park visits per week was associated with a significant and incremental decrease in stress (change in PSS10-0.53; 95% CI [-0.89, -0.16]; p = 0.005) at three months.

Conclusion

While we were unable to demonstrate the additional benefit of group park visits, we observed an overall decrease in parental stress both overall and as a function of numbers of park visits per week. Paradoxically the park prescription without group park visits led to a greater increase in weekly park visits than the group visits. To understand the benefits of this intervention, larger trials are needed.

Trial registration

ClinicalTrials.gov NCT02623855.