Relations of residential green and blue spaces with new-onset chronic kidney disease

We investigated the associations of residential green and blue spaces with chronic kidney disease (CKD) incidence, which have rarely been examined.A total of 346,697 participants from UK Biobank without CKD at baseline were included. Land coverage percentages of residential green and blue spaces at 300 m and 1000 m buffer were estimated using land use data. The primary outcome was new-onset CKD ascertained through linkage to health administrative datasets.During a median follow-up of 12.0 years, 10,101 new-onset CKD were documented. Overall, there were significant inverse associations of residential green space coverage at 300 m (per SD [21.7 %] increment, HR,0.96, 95%CI, 0.94-0.98) and 1000 m (per SD [20.7 %] increment, HR, 0.96, 95%CI, 0.94-0.98) buffer, and blue space at 300 m (per SD [1.1 %] increment, HR, 0.97, 95%CI, 0.95-1.00) and 1000 m (per SD [1.2 %] increment, HR, 0.97, 95%CI, 0.95-1.00) buffer with the risk of new-onset CKD. Moreover, at 300 m buffer, a significantly lower risk of new-onset CKD (HRs ranging from 0.88 to 0.90) was found in participants with both higher green space and higher blue space (both of them in the 2nd or 3rd tertile, and at least one in the 3rd tertile). At 1000 m buffer, a significantly lower risk of new-onset CKD (HRs ranging from 0.79 to 0.89) was found in participants with either higher green space or higher blue space (either one in the 2nd or 3rd tertile). Furthermore, PM2.5 did not significantly modify the association of exposure to green and blue space with the risk of CKD (all P for interactions >0.05).Residential green and blue spaces, especially at larger buffer sizes, might be protective factors against new-onset CKD.