What types of green space disrupt a lonelygenic environment? A cohort study

Associations between green space type and social loneliness (a scarcity of people one feels they can depend on) were investigated in city-living participants in the Sax Institute's 45 and Up Study.

Availability of green space, tree canopy and open grass were measured as a percentage of land-use within 1.6 km road-network distance buffers using high-resolution data. Multilevel logistic regressions adjusted for confounding tested associations between each green space indicator with the odds of social loneliness at baseline (prevalence) and follow-up (incidence), adjusted for demographic and socioeconomic confounders.

The prevalence of social loneliness at baseline was 5.3% (n = 5627 /105,498). Incidence of social loneliness at follow-up was 3.4% (n = 1772/51,365). Adjusted regressions indicated reduced odds of prevalent (OR = 0.95, 95%CI = 0.92-0.98) and incident social loneliness with 10% more green space (OR = 0.92, 95%CI = 0.90- 0.96). Similar associations were found with a 10% increase in tree canopy for both prevalent (OR = 0.92, 95%CI = 0.88-0.95) and incident social loneliness (OR = 0.92, 95%CI = 0.88-0.97). Two-way interaction terms indicated effect modification by sex but not couple status. Among women, a 10% increase in total green space was associated with lower odds of prevalent (OR = 0.95, 0.91-0.95) and incident (OR = 0.89, 0.85-0.95) social loneliness. A 10% increase in tree canopy among women was associated with lower odds of prevalent (OR = 0.89, 085-0.92) and incident (OR = 0.85, 0.80-0.92) social loneliness. Meanwhile, a 10% increase in open grass among women was associated with higher odds of prevalent (OR = 1.08, 1.01-1.15) and incident (OR = 1.19, 1.03-1.35) social loneliness. Associations for men were statistically significant for a 10% increase in total green space (OR = 0.96, 0.92-0.99) and tree canopy (OR = 0.93, 0.90-0.97) for prevalent social loneliness only.

Urban greening and tree canopy restoration may reduce risks of social loneliness, perhaps especially in women.