| Popis: |
Background : While exposure to urban green spaces has been associated with various physical health benefits, the evidence linking these spaces to lower BMI, particularly among older people, is mixed. We suggest that dimensions of green space accessibility, which are generally unobserved in the existing literature, may be a source of this volatility in results. Methods: We conduct a cross-sectional study combining data from The Irish Longitudinal Study on Ageing and detailed land use information. We proxy respondents’ exposure to green spaces at their residential addresses in network buffers, which are adjusted to account for the density of local footpaths. Generalised linear models are used to test the association between exposure to accessible green space and BMI. Results: Relative to the third quintile, exposure to the two lowest quintiles of green space, as measured within a 1600m accessible network buffer, is associated with slightly higher BMI (marginal effect for lowest quintile: 0.88; 95% CI: 0.24-1.53; marginal effect for second quintile: 0.61; 95% CI: 0.02-1.2). The results, however, are not robust to small changes in how green space is measured and no statistically significant association between green spaces and BMI is found under other variants of our regression model. Conclusion : The relationship between green spaces and BMI among older adults is highly sensitive to the characterisation of local green space. While footpath availability offers a partial explanation to some unintuitive empirical results previously found in the literature, our results suggest that there remains some other unobserved factor which mediates the relationship between green spaces and weight status. |
