Long-term exposure to residential greenness and neurodegenerative disease mortality among older adults: a 13-year follow-up cohort study

Abstract

Background Living in greener areas is associated with slower cognitive decline and reduced dementia risk among older adults, but the evidence with neurodegenerative disease mortality is scarce. We studied the association between residential surrounding greenness and neurodegenerative disease mortality in older adults. Methods We used data from the 2001 Belgian census linked to mortality register data during 2001–2014. We included individuals aged 60 years or older and residing in the five largest Belgian urban areas at baseline (2001). Exposure to residential surrounding greenness was assessed using the 2006 Normalized Difference Vegetation Index (NDVI) within 500-m from residence. We considered all neurodegenerative diseases and four specific outcomes: Alzheimer’s disease, vascular dementia, unspecified dementia, and Parkinson’s disease. We fitted Cox proportional hazard models to obtain hazard ratios (HR) and 95% confidence intervals (CI) of the associations between one interquartile range (IQR) increment in surrounding greenness and neurodegenerative disease mortality outcomes, adjusted for census-based covariates. Furthermore, we evaluated the potential role of 2010 air pollution (PM2.5 and NO2) concentrations, and we explored effect modification by sociodemographic characteristics. Results From 1,134,502 individuals included at baseline, 6.1% died from neurodegenerative diseases during follow-up. After full adjustment, one IQR (0.22) increment of surrounding greenness was associated with a 4–5% reduction in premature mortality from all neurodegenerative diseases, Alzheimer’s disease, vascular and unspecified dementia [e.g., for Alzheimer’s disease mortality: HR 0.95 (95%CI: 0.93, 0.98)]. No association was found with Parkinson’s disease mortality. Main associations remained for all neurodegenerative disease mortality when accounting for air pollution, but not for the majority of specific mortality outcomes. Associations were strongest in the lower educated and residents from most deprived neighbourhoods. Conclusions Living near greener spaces may reduce the risk of neurodegenerative disease mortality among older adults, potentially independent from air pollution. Socioeconomically disadvantaged groups may experience the greatest beneficial effect.

Environmental risk factors of incident distal sensorimotor polyneuropathy: Results from the prospective population-based KORA F4/FF4 study

“…We used the NDVI to estimate greenness in the vicinity of participants' residences and found only weak associations with incident DSPN when analysing the whole study sample. Based on the associations between lower residential greenness and higher cardiometabolic and neurodegenerative disease risk (Twohig-Bennett and Jones, 2018;Rodriguez-Loureiro et al, 2022), such an association would also be plausible for DSPN. The neighbourhood and physical environment have only recently been discussed as potential determinants of DSPN, with physical activity, glycaemic control in people with diabetes and overall stress levels being the possible mediators (Hill-Briggs et al, 2020;Pop-Busui et al, 2022).…”

“…Of note, experimental studies found cold exposure related to sensory neuropathy and decreased nerve conduction velocity (NCV) (Vale et al, 2017;Maetzler et al, 2012). Greenspace exposure and residential greenness have been related to decreased risk of diabetes, cardiovascular and neurodegenerative disease and mortality (Twohig-Bennett and Jones, 2018;Rodriguez-Loureiro et al, 2022), possibly mediated by healthier lifestyle behaviours and attenuated stress-related pathways, but again DSPN has not been considered as a study outcome. Given the existing literature on the aforementioned mechanisms and outcomes, an association between lower greenspace exposure and higher risk of DSPN would appear plausible.…”

“…Second, disease risk depends on individual susceptibility. There is increasing evidence that people with obesity or related comorbidities represent a particularly vulnerable subgroup of the population (Sacks et al, 2011;Weichenthal et al, 2014;Yang et al, 2018;Kim et al, 2019;Herder et al, 2020;Kim et al, 2021;Li et al, 2021), suggesting that potential effect modification by obesity might exist.…”

The role of geographic information system and global positioning system in dementia care and research: a scoping review

“…These spatial analyses include spatial interpolation [57, 66, 81, 96-98, 101, 102], buffer analysis [54,67,[102][103][104][105], overlay analysis [97], land-use regression [4,106], satellite imaging [107], aerial photograph analysis [108], space syntax analysis [109], noise estimation [110], spatial linkage and aggregation [75,87,89,111,112], distancebased analysis [113]. These techniques were used to measure environmental factors such as air pollutant exposures [4,57,66,97,98,101,102,106,107], green and blue spaces [54,102,104,105,112], organophosphorus (OP) exposure [67], aluminum concentration [81], hilliness [103] and arsenic level [96]. Furthermore, the studies calculate sidewalk coverage [108] and…”

Longitudinal Impacts of Precision Greenness on Alzheimer’s Disease

“…In particular, high levels of greenness – such as trees, shrubs, or other ground cover – has been shown to be cross-sectionally associated with reduced rates of AD ( 9 , 10 ), and with risk factors for AD including cardiometabolic and cardiovascular disease ( 11 – 13 ). In addition, longitudinal research has linked greenness to lower AD mortality ( 14 ). More broadly, higher greenness has been associated with reduced risk for Parkinson’s disease, depression, and stroke, further reinforcing that greenness’ health impacts extend beyond a single chronic condition or a single diagnostic category ( 10 , 15 – 17 ).…”