Aging Ment Health. 2026 Jun 7:1-16. doi: 10.1080/13607863.2026.2678989. Online ahead of print.
ABSTRACT
BACKGROUND: Evidence linking residential environments to Alzheimer’s disease (AD) and mild cognitive impairment (MCI) remains limited.
METHODS: We followed 426,220 dementia-free UK Biobank participants for a median 13.6 years. Cox models evaluated associations between green, blue spaces, and natural environment (300 and 1000 m buffers) and AD/MCI risk, alongside exploratory mediation and gene-environment interactions.
RESULTS: Incident cases included 3513 AD and 864 MCI. For AD, higher green space, blue space, and natural environment within 300 m lowered risk (decreases of 5.8, 0.8, and 5.7% per IQR, respectively). At 1000 m, only green space (6.7%) and natural environment (5.7%) remained inversely associated. Blue space exhibited a non-linear AD association. For MCI, green and natural spaces consistently lowered risk across both buffers (14.9-22.2% reductions); blue space was non-significant. Analyses showed limited mediation by air pollutants and selective additive gene-environment synergy.
CONCLUSION: Higher residential green space and natural environment are observationally associated with reduced AD and MCI risks, whereas blue space associations with MCI remain inconclusive. Underlying mechanisms and exploratory gene-environment synergies require further validation.
PMID:42251690 | DOI:10.1080/13607863.2026.2678989
