Tsai Wei-Lun, Nash Maliha S, Rosenbaum Daniel J, Prince Steven E, D'Aloisio Aimee A, Neale Anne C, Sandler Dale P, Buckley Timothy J, Jackson Laura E
Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA.
Office of Research and Development, U.S. Environmental Protection Agency, Newport, OR, USA.
Environ Res. 2021 Aug;199:111327. doi: 10.1016/j.envres.2021.111327. Epub 2021 May 19.
Excess body weight is a risk factor for many chronic diseases. Studies have identified neighborhood greenery as supportive of healthy weight. However, few have considered plausible effect pathways for ecosystem services (e.g., heat mitigation, landscape aesthetics, and venues for physical activities) or potential variations by climate. This study examined associations between weight status and neighborhood greenery that capture ecosystem services most relevant to weight status across 28 U.S. communities. Weight status was defined by body mass index (BMI) reported for 6591 women from the U.S. Sister Study cohort. Measures of greenery within street and circular areas at 500 m and 2000 m buffer distances from homes were derived for each participant using 1 m land cover data. Street area was defined as a 25 m-wide zone on both sides of street centerlines multiplied by the buffer distances, and circular area was the area of the circle centered on a home within each of the buffer distances. Measures of street greenery characterized the pedestrian environment to capture physically and visually accessible greenery for shade and aesthetics. Circular greenery was generated for comparison. Greenery types of tree and herbaceous cover were quantified separately, and a combined measure of tree and herbaceous cover (i.e., aggregate greenery) was also included. Mixed models accounting for the clustering at the community level were applied to evaluate the associations between neighborhood greenery and the odds of being overweight or obese (BMI > 25) with adjustment for covariates selected using gradient boosted regression trees. Analyses were stratified by climate zone (arid, continental, and temperate). Tree cover was consistently associated with decreased odds of being overweight or obese. For example, the adjusted odds ratio [AOR] was 0.92, 95% Confidence Interval [CI]: 0.88-0.96, given a 10% increase in street tree cover at the 2000 m buffer across the 28 U.S. communities. These associations held across climate zones, with the lowest AOR in the arid climate (AOR: 0.74, 95% CI: 0.54-1.01). In contrast, associations with herbaceous cover varied by climate zone. For the arid climate, a 10% increase in street herbaceous cover at the 2000 m buffer was associated with lower odds of being overweight or obese (AOR: 0.75, 95% CI: 0.55-1.03), whereas the association was reversed for the temperate climate, the odds increased (AOR: 1.19, 95% CI: 1.05-1.35). Associations between greenery and overweight/obesity varied by type and spatial context of greenery, and climate. Our findings add to a growing body of evidence that greenery design in urban planning can support public health. These findings also justify further defining the mechanism that underlies the observed associations.
超重是许多慢性疾病的一个风险因素。研究已确定社区绿化有助于保持健康体重。然而，很少有人考虑生态系统服务（如缓解热量、景观美学和体育活动场所）的合理影响途径或因气候而产生的潜在差异。本研究调查了美国28个社区中体重状况与社区绿化之间的关联，这些绿化涵盖了与体重状况最相关的生态系统服务。体重状况由美国姐妹研究队列中6591名女性报告的体重指数（BMI）定义。使用1米土地覆盖数据为每个参与者得出其家周围500米和2000米缓冲距离内街道区域和圆形区域的绿化指标。街道区域定义为街道中心线两侧各25米宽的区域乘以缓冲距离，圆形区域是每个缓冲距离内以家为中心的圆的面积。街道绿化指标描述了行人环境，以获取用于遮荫和美学的实际和视觉上可及的绿化。生成圆形绿化用于比较。分别对树木和草本植物覆盖的绿化类型进行量化，还包括树木和草本植物覆盖的综合指标（即总绿化）。应用考虑社区层面聚类的混合模型来评估社区绿化与超重或肥胖（BMI>25）几率之间的关联，并对使用梯度提升回归树选择的协变量进行调整。分析按气候区（干旱、大陆性和温带）分层。树木覆盖始终与超重或肥胖几率降低相关。例如，在28个美国社区中，在2000米缓冲距离处街道树木覆盖增加10%，调整后的优势比[AOR]为0.92，95%置信区间[CI]：0.88 - 0.96。这些关联在不同气候区都成立，在干旱气候区AOR最低（AOR：0.74，95% CI：0.54 - 1.01）。相比之下，与草本植物覆盖的关联因气候区而异。对于干旱气候，在2000米缓冲距离处街道草本植物覆盖增加10%与超重或肥胖几率降低相关（AOR：0.75，95% CI：0.55 - 1.03），而在温带气候区这种关联则相反，几率增加（AOR：1.19，95% CI：1.05 - 1.35）。绿化与超重/肥胖之间的关联因绿化类型、空间背景和气候而异。我们的研究结果增加了越来越多的证据，表明城市规划中的绿化设计可以支持公共健康。这些发现也证明有必要进一步确定所观察到的关联背后的机制。
