The associations between social, built and geophysical environment and age-specific dementia mortality among older adults in a high-density Asian city

Abstract

Background: Although socio-environmental factors which may affect dementia have widely been studied, the mortality of dementia and socio-environmental relationships among older adults have seldom been discussed.Method: A retrospective, observational study based on territory-wide register-based data was conducted to evaluate the relationships of four individual-level social measures, two community-level social measures, six short-term (temporally varying) environmental measures, and four long-term (spatially varying) environmental measures with dementia mortality among older adults in a high-density Asian city (Hong Kong), for the following decedents: 1) all deaths: age >=65, 2) “old-old”: age >= 85, 3) “mid-old”: aged 75 - 84, and 4) “young-old”: aged 65 – 74.Results: This study identified 5438 deaths (3771 old-old; 1439 mid-old; 228 young-old) from dementia out of 228,600 all-cause deaths among older adults in Hong Kong between 2007 and 2014. Generally, regional air pollution, being unmarried or female, older age, and daily O3 were associated with higher dementia mortality, while more urban compactness and greenness were linked to lower dementia mortality among older adults. Specifically, being unmarried and the age effect were associated with higher dementia mortality among the “old-old”, “mid-old” and “young-old”. Regional air pollution was linked to increased dementia mortality, while urban compactness and greenness were associated with lower dementia mortality among the “old-old” and “mid-old”. Higher daily O3 had higher dementia mortality, while districts with a greater percentage of residents whose native language is not Cantonese were linked to lower dementia mortality among the “old-old”. Economic inactivity was associated with increased dementia mortality among the “young-old”. Gender effect varied by age.Conclusion: The difference in strengths of association of various factors with dementia mortality among different age groups implies the need for a comprehensive framework for community health planning. In particular, strategies for air quality control, usage of greenspace and social space, and activity engagement to reduce vulnerability at all ages are warranted.

Trends in the effects of ambient PM 2.5 concentration on mortality risk in Hong Kong, China

“…Those results are consistent with a previous study reported by Ho et al (2018) using Poisson regression models and hazy days as a predictor. For some recent time windows, there were some associations between DECH and deaths associated with mental and behavioral problems, which is consistent with a study reported by Ho et al (2020) that focused on associations between dementia mortality and environmental pollution. One possible reason for the association between DECH and mental-cause mortality in recent years is that society is paying more attention to mental and behavioral problems, and deaths related to mental health may have been misclassi ed in the past.…”

How can urban environments support dementia risk reduction? A qualitative study

“…However, such a holistic perspective is fairly new in the evolving concept of brain health. 16 Only in recent years, researchers started to investigate environmental impacts on dementia development, with air and noise pollution [17][18][19] and the built and green environment [20][21][22] being considered as potential factors. For example, Liu et from health insurance claims in older Taiwanese citizens and linked it to environmental measures: odds for dementia were lower in environments with more playgrounds, sports venues and community centers.…”