Greenness and Asthma in the Middle-Aged and Elderly Population in a Prospective Cohort Study — China, 2011–2018

What is already known about this topic? Greenness, which refers to the density of vegetated land, has been identified as an essential component of a healthy built environment for human health. Residential environment plays a critical role in the progression of early-onset or late-onset asthma.What is added by this report? Based on the China Health and Retirement Longitudinal Study from 2011 to 2018, this study indicates a negative association between greenness and asthma in the middle-aged and elderly population.What are the implications for public health practice? This study provides further guidance for environmental policymaking in city planning and public health protection to increase greenness in order to counteract the adverse health effects associated with rapid urbanization processes.