Living near greener spaces is associated with lower risk of diabetes-related mortality in Brussels, Belgium: a 13-year mortality follow-up study”

Background/Aim: Living in greener areas has been related to a lower risk of diabetes disease, but few studies have explored its association with diabetes-related mortality. This study examined the relationship between objective and subjective indicators of residential urban green spaces (UGS) and diabetes-related mortality in Brussels.Methods: We used data from the 2001 Belgian census linked to migration and mortality register data during 2001-2014. We included objective indicators of UGS within 300m buffers from the residential address (surrounding greenness -NDVI-; surrounding green spaces -Urban Atlas-) and an area-level subjective indicator of perceived neighbourhood greenness. We considered the full causal chain of events leading to death, i.e. we included deaths from diabetes as both the original cause of death and as any cause of death (immediate, intermediate, original or additional). Cox proportional hazards models were conducted to obtain hazard ratios (HR) for diabetes-related mortality. Models were adjusted for age, gender, migrant background, education, housing tenure, PM2.5, night noise levels and area-level socioeconomic status (percentage of unemployed). Effect modification by gender, education and migrant background was assessed.Results: We included 734,806 individuals aged 16-80 in 2001. We observed 1,318 (1.5%) deaths from diabetes as the original cause and 5,268 (6.1%) deaths from diabetes as any cause. IQR increases of both surrounding and perceived neighbourhood greenness were inversely associated with diabetes-related mortality. Associations were stronger for diabetes as the original cause of death (e.g. with surrounding greenness: aHR:0.83, 95%CI:0.74-0.93). No associations were found for surrounding green spaces after adjusting by area-level SES. We observed a significant interaction between perceived neighbourhood greenness and gender with diabetes-related mortality: beneficial associations were stronger among women (for diabetes as original cause of death: aHR:0.80, 95%CI:0.69-0.94).Conclusions: Our findings suggest that living near UGS in Brussels might reduce diabetes-related mortality risk. The perception of neighbourhood greenness might be crucial among women.