Association between residential greenness and cognitive function
| Exposure metric | Serial cross-sectional analysis (n=38 327) | Longitudinal analysis (n=19 726) | ||
| Linear regression | Logistic regression | Linear mixed effects regression | Logistic mixed effects regression | |
| Coefficient for change in MMSE score (95% CI) | OR of cognitive impairment (95% CI) | Coefficient for change in MMSE score (95% CI) | OR of cognitive impairment (95% CI) | |
| 0.1-unit of NDVI | 0.23 (0.16 to 0.29) | 0.94 (0.92 to 0.96) | 0.069 (0.0048 to 0.13) | 0.99 (0.97 to 1.01) |
| Quartiles of NDVI | ||||
| Quartile 1 | Reference | Reference | Reference | Reference |
| Quartile 2 | 0.23 (−0.015 to 0.48) | 0.99 (0.92 to 1.08) | −0.046 (−0.29 to 0.19) | 1.08 (1.00 to 1.18) |
| Quartile 3 | 0.24 (−0.027 to 0.50) | 0.93 (0.86 to 1.02) | −0.019 (−0.27 to 0.23) | 1.04 (0.95 to 1.14) |
| Quartile 4 | 0.99 (0.72 to 1.26) | 0.75 (0.69 to 0.82) | 0.33 (0.068 to 0.58) | 0.92 (0.84 to 1.01) |
All the regression models were adjusted for age, gender, ethnicity, marital status, urban/rural residence, education, occupation, financial support, social and leisure activity, smoking status, alcohol consumption and physical activity at baseline. The longitudinal analysis was additionally adjusted for the time to reflect the number of years for each follow-up survey since entering the cohort.
MMSE, Mini-Mental State Examination; NDVI, Normalised Difference Vegetation Index.