Objective Sleep disorders pose a significant threat to the physical and mental health of the elderly and have emerged as one of the key public health challenges in aging societies. As accessible natural elements within urban environments, green spaces offer unique advantages for improving environmental quality, regulating microclimates, and promoting physical and mental relaxation, offering new perspectives for interventions targeting sleep health among the elderly. However, current research remains fragmented regarding the underlying mechanisms and lacks systematic integration of optimization pathways. This gap urgently necessitates in-depth exploration from multidisciplinary perspectives. This research aims to synthesize multidisciplinary theories in order to construct a systematic evidence framework elucidating the association between urban green spaces and sleep health of the elderly, thereby providing a scientific basis for optimizing the design of age-friendly urban spaces.

Methods This research searches the Web of Science database for English-language literature and the CNKI database for Chinese-language literature published since 2000 regarding the role of green spaces in promoting sleep health of the elderly. Literature inclusion criteria: 1) Research objects should be aged 60 or above; 2) research types include empirical research, review, and meta-analysis; 3) publication date should be within the period from January 1, 2000, to the search cutoff date (January 1, 2025). After strict screening, a total of 452 literature articles are ultimately identified for inclusion and analysis.

Results It is found through analysis that relevant research primarily focuses on disciplines including geriatrics and gerontology, neuroscience and neurology, psychiatry, psychology, behavioral science, sociology, rehabilitation medicine, exercise science, environmental science, and ecology. The decline in sleep quality of the elderly stems from the interplay between age-related physiological decline and multiple environmental factors. The underlying mechanisms can be categorized into two dimensions: 1) Intrinsic physiological – psychological mechanisms, involving degenerative changes in sleep structure and circadian rhythms, along with the superimposed effects of chronic diseases; 2) extrinsic environmental stress systems, involving stress responses induced by noise pollution, circadian rhythm disruption resulting from light pollution, oxidative stress damage caused by carbon-oxygen imbalance and air pollution, as well as the environmental – psychological dilemmas associated with social isolation. Urban green spaces contribute to regulating circadian rhythms, prolonging deep sleep duration, and reducing sleep fragmentation via multiple pathways: 1) Environmental regulation: improving microclimates through green vegetation, optimizing air quality, and attenuating noise to enhance the acoustic environment; 2) behavioral promotion: facilitating physical activity within green spaces; 3) social support: cognitive restoration promoted by natural landscapes and the environmental – psychological benefits of social interaction; 4) stress relief: natural regulation of HPA axis activity and green-mediated inhibition of inflammatory responses; 5) circadian regulation: regulation via natural light exposure. Significant individual variations in these health benefits, influenced by genetics, are also identified. Genetically, polymorphisms in circadian rhythm genes influence sleep patterns of the elderly. Regarding the microbiome, the gut-brain axis plays a crucial role. The elderly with genetically susceptible gut microbiota may experience distinct sleep improvement effects from green spaces compared to those with more stable gut microbiota compositions. Additionally, culturally-specific lifestyle patterns and attitudes toward nature may lead to variations in sleep improvement outcomes among the elderly from diverse cultural backgrounds when they use green spaces.

Conclusion Research on improving sleep health of the elderly must transcend single-discipline limitations, integrating theories and research methods from multiple fields including geriatrics and gerontology, neuroscience and neurology, psychiatry, psychology, behavioral science, sociology, rehabilitation medicine, exercise science, and environmental science and ecology. This interdisciplinary approach is essential to collaboratively unravel the pathways of the “green spaces – physiological + psychological responses – sleep quality” mechanism. To further improve sleep quality of the elderly, it is essential to enhance the “intervention dosage” (impact) of urban green spaces through multi-dimensional approaches and establish a systematic, precision-oriented “green sleep prescription” system. As the primary and most frequently accessed green spaces for the elderly, community green spaces and residential greening constitute critical foundational elements for enhancing sleep health. Leveraging their inherent advantages of convenient accessibility and high usage frequency, they play an irreplaceable, proactive, and sustained role in improving sleep quality. Consequently, prioritizing the advancement of their planning, design, and functional optimization is imperative. Finally, rigorous evaluation of the effectiveness of sleep quality improvement interventions is essential. In summary, future research should establish a complete closed loop of “scientific research − prescription development − design implementation − effect evaluation”, grounded in deepened mechanistic understanding. This effort should focus on achieving breakthroughs in precision design and tailored activity plans for diverse elderly groups, providing innovative solutions for healthy aging and a scientific basis for implementing the “Healthy China” strategy.