Residential green space, natural environment, domestic garden, and the risk of Parkinson's disease: A prospective cohort study.

BACKGROUND

The relationship between residential greenness and the risk of neurodegenerative disorders, along with the role of genetic susceptibility, remains incompletely understood. This study aimed to examine the association between residential greenness and the incidence of neurodegenerative disorders.

METHODS

Using data from up to 220,000 participants with no prior neurodegenerative disorders at baseline, we utilized Cox proportional hazard model and restricted cubic spline regression to assess associations between residential greenness and the incidence of Parkinson's disease (PD), Alzheimer's disease (AD), and multiple sclerosis (MS). Stratified analyses were conducted by sex, age, body mass index, smoking, alcohol intake, polygenic risk scores, Townsend deprivation index, residential area type, and air pollution score.

RESULTS

Over a median follow-up of 10.8 years, 1211, 1054, and 411 participants developed PD, AD, and MS, respectively. Higher greenness was associated with reduced PD risk, especially 300-m buffer natural environment (HR = 0.537, [0.312, 0.92]) and 1000-m buffer green space (HR = 0.667, [0.458, 0.972]). Conversely, 300-m buffer green space was linked to increased AD risk (HR = 1.623, [1.007, 2.615]). Stratified analyses indicated stronger protective effects of natural environment against PD among older individuals and smokers. At both 300-m and 1000-m buffer green space, participants with high genetic susceptibility was linked to reduced PD risk. These benefits were more pronounced among socioeconomically disadvantaged individuals and those in highly air pollution areas.

CONCLUSION

Our findings suggest that different types and distance of exposure to residential greenness may exert varying influences on neurodegenerative disorders.