Impact of urbanization on cognitive disorders

Abstract

Purpose of review-Cognitive disorders remain a major global burden with an estimated 47 million people living with dementia worldwide. Rates of cognitive disorders are expected to grow, especially as the global population ages. Global trends also indicate that about half of the global population lives in urban settings. To help guide future research, as well as the development of targeted and tailored interventions to prevent and care for people living with cognitive disorders, we present an up-to-date review and summary of the literature examining cognitive disorders and urbanization. Recent findings-We reviewed the literature between January 2017 and September 2018 on cognitive disorders and urbanization. We found that rates of dementia among urban dwellers tends to be lower than those of rural dwellers. Leading theories explaining this difference tend to focus on better access to higher quality education, as well as public and health services among urban dwellers. We also found that greater exposure to air and noise pollutants may negatively impact cognition. Summary-The reasons why older adults living in urban settings appear to have lower rates of dementia and better performance on cognitive measures are not well understood. Furthermore, the definitions of urban and rural and,cognitive disorder,a s well as how they are measured vary greatly between studies, making comparisons difficult.

Community-level Educational Attainment and Dementia: A 6-year Longitudinal Multilevel Study in Japan

“…Our study is consistent with review articles that found that people living in urban centers tended to develop dementia less than those in rural areas [7,30]. Although there was an unequal distribution or a lack of resources related to better cognitive function (health clinics, bookstores, and libraries) due to the de cit of educated consumer demand or taxes for such resources in lower education communities [26], this may more easily happen in non-urban areas than in urban areas.…”

“…A systematic review with a meta-analysis concluded that early life rural living was strongly associated with a risk of Alzheimer's disease [30]. In addition, previous studies have mentioned that rural areas had educational inequality, such as more insu cient educational opportunities and less quality of education [7,31]. Although some children left rural areas and proceeded to higher grade schools in urban areas [31], many participants in the current study may live in the same rural areas where they received education for a long time [32].…”

“…Another review identi ed that living in urban areas was likely to reduce cognitive decline risk when compared to those in rural areas [7]. On the other hand, a recent US study showed that the prevalence of dementia declined more signi cantly among adults living in rural areas than those in urban areas over the past few decades as a result of improving educational attainment [8].…”

“…Third, it was not common to adjust for confounding factors such as residential years [6,9]. Fourth, exploring the relationship between community-level educational attainment and dementia among urban and rural older adults was insu cient [7,8]. Overcoming the limitations of the aforementioned studies, this longitudinal study with large sample size data aimed to examine whether older populations living in communities with a higher proportion of lower educational attainment have the risk of dementia incidence when compared to those living in communities with a lower proportion of less education after controlling for individual-level educational years.…”

The Association of Meteorological Factors with Cognitive Function in Older Adults

“…Previous studies have shown that environmental factors such as urbanization and traffic (e.g., highway construction) have been associated with cognitive function in older age [9][10][11][12]. For example, living in cities appears to reduce the risk of cognitive impairment, although the exact reasons are unclear [12,13].…”