Ishikawa, Japan -- Depression is a chronic mental health condition that can impact one's physical health and well-being. Globally, approximately 280 million people of all ages experience depression, including 5% of all adults and 5.7% of older adults. As a result, reducing the global burden of depression has become an urgent matter. In this regard, identifying modifiable factors that can aid in the prevention and management of depressive symptoms is crucial.

The “built environment,” which includes man-made spaces meant for daily life, work, or recreation, can be modified in terms of the design, structure, facilities, and services. The effect of the built environment on the health and well-being of inhabitants has been studied previously. However, empirical studies on this subject are lacking, especially for middle-aged adults.

To bridge this gap, a team of researchers led by Associate Professor Mohammad Javad Koohsari at the Japan Advanced Institute of Science and Technology (JAIST), who is also an adjunct researcher at Waseda University, examined how the built environment influences depressive symptoms among middle-aged adults. Explaining the novel nature of this study, Dr. Koohsari says “This study used both perceived and objective measures of the built environment and focused on the less-studied age group of middle-aged adults.”

The team comprised Professor Kaori Ishii and Professor Koichiro Oka from Waseda University, Professor Tomoki Nakaya and Associate Professor Tomoya Hanibuchi from Tohoku University, Associate Professor Ai Shibata from the University of Tsukuba, Professor Akitomo Yasunaga from Bunka Gakuen University, Associate Professor Gavin R. McCormack from the University of Calgary (Canada), and Professor Yukari Nagai from JAIST.

The authors used the Centre for Epidemiological Studies Depression (CES-D) questionnaire to assess depressive symptoms among adults aged 40-64 years in two cities in Japan. To study how this correlated with the built environment, they carried out objective assessments of population density, number of traffic intersections, and the availability of destinations. In addition, they also assessed people’s perception of their environment, i.e., whether the people feel that public transport is accessible and there is adequate safety from crime. Their findings were published online on December 1, 2022, in the journal Landscape and Urban Planning.

The highlight of their findings is that objective attributes did not correlate with the odds of having depressive symptoms. However, the researchers found that perceived attributes, such as higher perceived walkability of the neighborhood, were related to lesser depressive symptoms among individuals. Moreover, the researchers noted that gender tends to determine the perceived attributes that influence mental health. Among women, the factors influencing depressive symptoms included higher perceived access to transport and safety from traffic. Meanwhile, among men, higher safety from crime was related to a decrease in depressive symptoms and lower odds of mild depressive symptoms.

While explaining their findings, Dr. Koohsari remarks, “Built environment design may influence depressive symptoms through several behavioral and social pathways. Our findings provide empirical behavioral insights that improving perceptions of neighborhood walkability and, in particular, enhancing access to public transport and safety from crime and traffic are important for improving depressive symptoms in middle-aged men and women.”

This study paves way for future research, where using comparable perceived and objective measures of the built environment can reveal whether design interventions to alleviate depressive symptoms should target residents’ perceptions, places, or both. Furthermore, given the difference in parameters that influence mental health among men and women, identifying other contextual reasons behind their perceptions might lead to more targeted solutions.

In a world where over 280 million people live with depression, a small step in the right direction in urban planning could translate into a giant leap in improving the mental health and wellbeing of people.



Title of original paper:Depression among middle-aged adults in Japan: The role of the built environment design
Authors:Mohammad Javad Koohsari*, Akitomo Yasunaga, Gavin R. McCormack, Ai Shibata, Kaori Ishii, Tomoki Nakaya, Tomoya Hanibuchi, Yukari Nagai, Koichiro Oka
Journal:Landscape and Urban Planning

About Japan Advanced Institute of Science and Technology, Japan
Founded in 1990 in Ishikawa prefecture, the Japan Advanced Institute of Science and Technology (JAIST) was the first independent national graduate school in Japan. Now, after 30 years of steady progress, JAIST has become one of Japan’s top-ranking universities. JAIST counts with multiple satellite campuses and strives to foster capable leaders with a state-of-the-art education system where diversity is key; about 40% of its alumni are international students. The university has a unique style of graduate education based on a carefully designed coursework-oriented curriculum to ensure that its students have a solid foundation on which to carry out cutting-edge research. JAIST also works closely both with local and overseas communities by promoting industry–academia collaborative research.

About Associate Professor Mohammad Javad Koohsari from Japan Advanced Institute of Science and Technology, Japan
Dr Koohsari is an Associate Professor at the School of Knowledge Science, Japan Advanced Institute of Science and Technology in Japan. Dr Koohsari's research focuses on how urban design and geospatial science can contribute to health, especially in the context of super-aged societies. Dr Koohsari has a publication record with over 100 refereed journal articles (such as at Nature Reviews Cardiology). In 2020 and 2021, he was recognised in the top 2% of most influential researchers worldwide across all scientific disciplines (Stanford University & Elsevier). He is also included in the 'Top Scientists' list in the field of 'Social Science & Humanities' for the year 2022 ( Dr Koohsari is on the editorial board member of several major journals in the field such as Landscape & Urban Planning and Humanities & Social Sciences Communications.

Funding information
This study was supported by a Japan Society for the Promotion of Sciences (KAKENHI
Grant 18KK0371 and 17H00947), JSPS KAKENHI (#20H00040), a Canadian Institutes of Health Research Foundations Scheme Grant (FDN-154331), and a Grant-in-Aid for Scientific Research (No. 20H04113) from the Japan Society for the Promotion of Science.

Journal Link: Landscape and Urban Planning