This study attempts to examine the relationship between the POS use and status of mental health among older residents in disadvantaged urban neighborhoods in Tehran, Iran. Due to the importance of the elderly mental health in underprivileged neighborhoods in international studies[30, 31], the lack of empirical evidence on disadvantaged urban neighborhoods, especially in the context of developing countries and Iran, calls the reliability and the wide application of such findings into question. The issue of mental health and use of POS is of particular significance in regard to the older residents, particularly in poor urban areas[30, 31]. Accordingly, this study used data on the mental health status of the more senior adults (420 elder residents) in the disadvantaged urban neighborhoods and their use of POS in District 10 in Tehran. It confirmed that the frequency of POS use might reduce mental health symptoms in older adults(feeling of worthiness) and increase their social interactions. In particular, in the absence of a database of the prevalence of mental disorders in the Iranian elder residents, this study provided a helpful perspective on promoting the health of the older adults (physical and mental) for policymakers, urban planning, and designing experts. The findings of the previous studies also show that POS use can increase the mental health status of the older residents as well as their social interactions[33, 34]. However, one of the problems of disadvantaged neighborhoods is the lack of adequate access to open spaces suitable for older residents. This issue requires the availability of green spaces and POS to increase their attendance for the more aged residents according to their environmental preferences [15, 17, 35].
The results of regression analysis of this study showed that the more the older residents attend POS, the less they suffer from the feeling of worthlessness and dissatisfaction with their lives and the more their social interactions and active presence in communities (being with friends, family, and social groups) will be. The studies conducted on the older residents show that an increase in the more senior residents’ social capital and social interactions can contribute to a healthy life and a successful aging process, leading finally to social health[15, 17]. However, this study showed that the older adults’ social interaction and social health outcomes from their presence in the community and having physical activity. The study conducted by Schmidt et al.( 2019) shows that when the older residents are engaged in social interaction, they are less inclined to walk, so their physical activity and physical health are less affected, but their mental health improves. This study also showed that the feeling of self-esteem in the older residents and their social performance are the consequence of and are reciprocally related to their mental health. A previous study conducted in Tehran also showed that based on the regression model results, variables such as gender, age, education, having a job, life satisfaction, and physical-movement limitation are significantly related to the mental health of Iranian older adults . Social participation is the essential factor in the mental health of the elderly in Iran .
Another finding of this study indicates that in disadvantaged urban neighborhoods, older women are more inclined to attend POS and have a better mental health status together with a sense of worthiness in their social interactions. This finding is consistent with Koohsari et al.(2019) study showed that the Japanese elder women who are more present in neighborhoods’ spaces have better mental health conditions in terms of depression.
Furthermore, our study revealed that those older residents who are married, employed, and more educated have better mental health status. Although they live in disadvantaged urban neighborhoods, they are more present in their neighborhoods’ POS, have more interactions with other people, and are more inclined to have social relationships. The reason behind this can be the higher level of self-confidence and self-esteem among these older residents.
Status of the elderly. Due to the insufficiency of appropriate POS in disadvantaged neighborhoods, our findings emphasize the importance of identifying older residents vulnerable to mental health issues based on demographic and social characteristics and the direct relationship between the proportion of POS and green spaces and the mental health status of older urban residents. The relation between The mental health outcomes, the ratio of green spaces, and the Sociodemographic status of the neighborhood was proved.
In recent years, the design and planning interventions aimed at reducing older residents’ health costs save been focused on promoting “active aging” spaces  and “aging in place” . This type of intervention emphasizes more opportunities to use POS in neighborhoods. Many studies have shown a positive association between creating POS and green spaces and mental health benefits[3, 39–42]. According to the quality of neighborhoods on the older people’s mental health, improving the neighborhood’s characteristics can lead to the social integration of older residents and higher social interactions [42–44]. Improving the neighborhood’s quality needs greater attention in disadvantaged urban neighborhoods due to the high density and the lack of sufficient POS as well as population density, deteriorated built environment, and sociodemographic status of residents. Therefore, in this study, we sought to examine the factors affecting the mental health of older urban residents (depression symptoms) and consider the effects of specific sociodemographic factors and POS use such as streets, squares, and local parks.
The findings of this study provide significant empirical data on planning and designing policies for “aging in place” in disadvantaged urban neighborhoods. Therefore, designing and planning urban spaces for vulnerable groups in terms of mental health and developing POS in disadvantaged neighborhoods based on the preferences and demands of the older residents should become a priority. This approach can encourage more senior residents to increase their attendance and use of POS. Meeting operational needs (appropriate density, land use mixing, green spaces in streets and squares, safety, proper flooring, lighting, proper landscape, environmental design), attending to environmental preferences (security against crime, landslides, and getting lost), and holding social and cultural events are among the factors that can improve the quality of public open spaces in neighborhoods. In addition, social interaction within neighborhoods’ public open spaces and parks can promote health and wellbeing  . As a result, when social interactions occur in a public setting, positive psychological changes can occur in older people through mutual understanding and interests.
The limitations of this study should be taken into consideration for interpreting the results of this study: (a) Although the minimum sample size requirement is observed in the present study, additional insights could be obtained by surveying more people - especially when it is considered that a limited sample with mental health problems were involved in this study; (b) Although the employed terms could accurately convey the message, it’s not generally proper to conceptualize people with terms such as “feeling of worthlessness”, and “social interaction”; (c) The present study only concentrated on a specific period; however, in order to get to more reliable and generalizable results, a longitudinal study with the same sample seems to be necessary. Our future studies can concentrate on solving these problems, investigating the possible correlation between the use of public open spaces and mental health status based on the specific characteristics of public open spaces in disadvantaged neighborhoods, and gaining a more comprehensive insight into the participants’ perceptions about public open spaces.