Introduction

Body size, a key risk factor for chronic diseases, is associated with longer commutes. This study assessed associations between residential proximity to capital city central business district (CBD), area-level commute distance, and individual-level body size (body mass index [BMI] and waist circumference [WC]), and whether commute distance partially explains associations between residential proximity and body size.

Methods

This study used 2017-18 National Health Survey (NHS) data for working adults (aged ≥15 years, n = 6394) residing in Australian capital cities. Measures included individual-level sociodemographic information and measured body size (BMI, WC), area-level (SA1) disadvantage, average commute distance, and population density. SA1-centroid distances to CBDs were calculated and grouped into tertiles. Multilevel linear regression models estimated city-specific associations between commute distance and body size, and residential proximity and body size, accounting for area clustering and sequentially adjusting for covariates.

Results

Commute distance was positively associated with BMI except in Adelaide and Darwin, and with WC in all cities except Darwin. Associations were largely unaffected by covariate adjustment in Sydney (β = 0.039, 95%CI: 0.004, 0.074) and Melbourne (β = 0.083, 95%CI: 0.045, 0.121) for BMI; and in Melbourne (β = 0.169, 95%CI: 0.074, 0.265) and Perth (β = 0.082, 95%CI: <0.001, 0.166) for WC. For other cities, associations were nullified. Distance to CBD was positively associated with BMI and WC in most cities, but robust to covariate adjustment (including commute distance) only in Darwin (BMI: middle tertile β = 1.60, 95%CI: 0.39, 2.81; WC: middle tertile β = 4.10, 95% CI: 0.45, 7.75) and Adelaide (WC: outer tertile β = 7.67, 95%CI: 2.65, 121.69).

Conclusion

Living in middle and outer areas of Australia's capital cities is associated with greater body size. Longer commute distance partially accounts for this association in some cities. Integrated multisector planning may help to reduce the association between residential distance to CBD and commute distance on body size and thus health.

中文翻译：

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居住地点、通勤距离和体型：澳大利亚各州和领地首府城市的横断面观察研究

介绍

体型是慢性病的一个关键风险因素，与更长的通勤时间有关。本研究评估了住宅与首都城市中央商务区 (CBD) 的距离、区域级别的通勤距离和个人级别的体型（体重指数 [BMI] 和腰围 [WC]）之间的关联，以及通勤距离是否部分解释了居住距离与体型之间的关联。

方法

本研究使用了居住在澳大利亚首府城市的在职成年人（年龄≥15 岁，n = 6394）的 2017-18 年全国健康调查 (NHS) 数据。测量包括个人层面的社会人口统计信息和测量的体型（BMI、WC）、区域层面（SA1）劣势、平均通勤距离和人口密度。计算到 CBD 的 SA1 质心距离并将其分组为三分位数。多级线性回归模型估计了通勤距离和身体大小、住宅邻近度和身体大小之间特定于城市的关联，考虑了区域聚类并依次调整协变量。

结果

除阿德莱德和达尔文外，通勤距离与 BMI 呈正相关，除达尔文外的所有城市都与 WC 呈正相关。在悉尼 (β = 0.039, 95%CI: 0.004, 0.074) 和墨尔本 (β = 0.083, 95%CI: 0.045, 0.121) 中，相关性在很大程度上不受协变量调整的影响；在墨尔本 (β = 0.169, 95%CI: 0.074, 0.265) 和珀斯 (β = 0.082, 95%CI: <0.001, 0.166) 为 WC。对于其他城市，协会被取消。在大多数城市，到 CBD 的距离与 BMI 和 WC 呈正相关，但仅在达尔文（BMI：中间三分位数 β = 1.60，95% CI：0.39，2.81；WC：中间三分位数 β = 4.10, 95% CI: 0.45, 7.75) 和阿德莱德 (WC: 外三分位数 β = 7.67, 95% CI: 2.65, 121.69)。

结论

居住在澳大利亚首府城市的中部和外围地区与更大的体型有关。在某些城市，较长的通勤距离部分解释了这种关联。综合多部门规划可能有助于减少到 CBD 的住宅距离和通勤距离与体型和健康之间的关联。