Background In the context of improving urban environment for healthy aging, it is necessary to rationally plan and provide community living space and public service facilities suitable for the elderly, and constantly optimize the built environment towards an age-friendly city.

Objective To understand the relationship between community built environment and obesity in the elderly in Longgang City, and to provide a reference basis for improving the health of the elderly.

Methods Elderly adults aged 60-90 years (n=6527) who completed a physical examination during the period from October 2020 to January 2021 in Longgang City were surveyed, and data on height and weight, waist circumference (WC), and other sociological demographic characteristics were obtained. Overweight was determined by 24 kg·m⁻² ≤ body mass index (BMI) < 28 kg·m⁻² and obesity by BMI ≥ 28 kg·m⁻². Men with WC ≥ 85 cm and women with WC ≥ 80 cm were considered central obesity. Based on the participants' residential addresses, geocoding was performed using a geographic information system, and built environment indicators such as restaurants, convenience stores, and basic medical facilities were obtained using Gaode Map. A binary logistic regression model with adjusted individual-level covariates was used to evaluate the relationship between obesity and built environment indicators among elderly adults by gender and age.

Results Among the 6527 community elderly, 46.93% were male and 53.07% were female, with a mean age of (73.69±0.07) years, a mean BMI of (24.32±2.84) kg·m⁻², and 51.92% of the elderly were overweight or obese. The regression results showed that for elderly men, the more convenience stores and the higher mixed land use in residential areas, the higher risk of central obesity; however, the increases in street connectivity and accessibility to parks and recreational areas were associated a decreased risk of central obesity. The prevalence of overweight/obesity was higher among elderly women with more convenience stores in residential areas, while increased street connectivity was associated with a lower prevalence of central obesity among elderly women. Accessibility to primary health care facilities was negatively associated with the risk of central obesity among the 60- to 70-year-olds. For elderly residents aged 71−80 years, higher mixed land use and better accessibility to transit stations were associated with a higher prevalence of overweight/obesity, while street connectivity was negatively associated with the central obesity. Proximity to parks and recreational areas was associated with a reduced risk of overweight/obesity among the 81- to 90-year-olds.

Conclusion Among the variables of a 500-m neighborhood built environment, the number of convenience stores, mixed land use, street connectivity, accessibility to primary health care facilities, accessibility to public transit stations, and accessibility to parks and recreational areas are correlated with obesity among elderly residents, and the degree of influence varies by gender and age.