1. Introduction
Mental health refers to emotional balance and social adjustment, comfort, the absence of mental illness, personality integration, and the knowledge of self and the environment (Belo et al. 2020). Aging is a biological and inevitable phenomenon and indicates the accumulation of changes in a person over time (Değer, et al., 2019). These changes include physical, psychological, and social aspects of a person’s life (Ghosh & Dinda, 2020; Patrick et al., 2020). Although the elderly population reflects general health, they encounter the challenge of maintaining the quality of life, functional capacity, and social participation (Martina et al. 2018). Older adults are vulnerable to mental disorders and physical and mental health challenges (WHO, 2017). According to the World Health Organization (WHO), more than 20% of the Iranian population will be elderly by 2030. The rapid increase in the number of elderly people in relation to the general population in recent years, the so-called “graying” of the world, is the result of the “demographic transition” process (Khodabakhshi-Koolaee & Froozani, 2018; Khodabakhshi-Koolaee et al., 2022).
The incidence of mental disorders, mostly depression and anxiety, is increasing in old people (de Oliveira et al., 2019). The World Health Organization (WHO) estimates that approximately one out of ten of the elderly suffers from depression, and this figure increases with age (WHO, 2019). Because depression is currently the leading cause of disability worldwide and increases with age (WHO, 2017), taking effective measures based on the related mediating factors is essential (Hallgren et al., 2017). The diagnosis and treatment of mental disorders in older adults should be considered. A mental disorder such as depression, if left untreated, inadequately treated, or showing resistance to treatment, can lead to another cascade of adverse health consequences such as malnutrition, physical weakness, poor performance, reduced quality of life, and ultimately death (Khodabakhshi-Koolaee, 2016). Older adults are more likely to experience events such as mourning and declining socioeconomic status with retirement or disability. These factors can lead to isolation, loss of independence, loneliness, and psychological distress in older people (WHO, 2019). In addition to the goal of increasing life expectancy and longevity of members of the community, the issue of increasing mental health, welfare, and quality of life has also attracted the attention of sociologists and health policymkers (Shah, Christian, Prajapati, & Patel, 2017). 
Mental health is an important factor in predicting death anxiety among older adults. People who do not consider themselves healthy are more aware of the certainty of death and are more likely to experience anxiety about death and dying issues (Geurtsen, 2010; Xu, Anderson, & Courtney, 2010). These age-related sociopsychological complexities have a strong negative effect on mental illness, making it more difficult to diagnose and manage mental health issues (Bhattacharyya, 2021). Because older adults will constitute a significant portion of the population, analyzing various aspects of their lives, especially the issue of their health, is important. 
Taking strategies to improve mental health insurance coverage, increase public awareness of mental disorders, and reduce regional disparities in mental health resources can guarantee mental health (Guo et al., 2019). According to Joshi (2018), older adults always face different health, financial, physical, and mental problems, which is why care for them should be the priority. Svensson and Hansson (2017) have pointed out that mental health care for older adults should be promoted based on a better procedure among public health care workers to identify mental illness and provide better access to effective treatment. Isolation and loneliness are common in old age; however, older adults differ in how they ease their loneliness. Also, different barriers exist in maintaining this social isolation (O’Rourke, 2020). Older adults are more prone to mental health problems due to old age and physical and mental disabilities, and their mental health disorders are more likely to be manifested in the form of anxiety and depression. Various studies have shown that older adults can be depressed due to social dysfunction, decreased cognitive function, and increased risk of death in old age (Pachana & Laidlaw, 2014). Nevertheless, social support, respect, economic welfare, and physical health have a tremendous impact on promoting the psychological health of older adults (Khodabakhshi-Koolaee & Mirzaei, 2018; Peyvakht et al., 2020).
Many factors are involved in promoting the psychological wellbeing of older adults. However, some of these factors depend on the older adults’ definition of life during old age and their experience in removing barriers to promote psychological development. These factors are among the psychological concepts that depend on many causes and factors, including contextual, cultural, social, and individual factors and personal attitudes. An exploration and awareness of factors promoting mental health in older adults affect not only their mental health but also their physical health and their quality of life. For example, people in Eastern cultures show a high level of respect and social support for old people. They consider elders wise people and admire the elderly in society. Policymakers and members of the community constantly promote these norms and values. On the other hand, social developments in big cities, the nuclearization of families, migration to cities or other countries for work and life, life problems, and economic challenges have diminished the importance of the presence of older adults. The significance of this study is examining the factors promoting mental health from the perspective of older retired adults who had higher education and had served as executives during their lifetime in Iranian society and the city of Tehran. These people were chosen because they had fewer economic worries and could discuss the issues addressed in this study. Thus, we aimed to identify the opinions and experiences of National Iranian Oil Company retirees on psychological wellbeing.

2. Participants and Methods
Study participants
This research was qualitative, and a grounded theory approach was applied. Qualitative research is often used to deeply understand a given subject or phenomenon. In the grounded theory, research hypotheses are developed within the research setting while conducting the study. In other research methods in the humanities, hypotheses are formed as part of the research process (Gall, Gall, & Borg, 2003). Because of the exploratory nature of the grounded theory approach, it is a suitable method for identifying the factors that promote mental health in older adults. Perhaps the most important difference between grounded theory and the other methods is the development and presentation of a theory from the heart of the data, and the researcher does not try to express only the views and opinions of the participants (Corbin and Strauss, 2014). Figure 1 shows the paradigm model of the factors promoting the psychological health of senior managers.

The participants in the present study were retired managers of the National Iranian Oil Company in 2021. The data were collected through semi-structured interviews with the participants selected by purposive sampling. The data were saturated after 15 interviews. That is, the interviews continued until no new information was revealed with additional interviews.
The participants were selected with maximum variation in terms of demographic characteristics from retired managers of the National Iranian Oil Company. They were also selected with maximum variation to enhance the transferability of the findings. The inclusion criteria were: (1) the participants were 60 to 65 years old; (2) they served in the top, senior, and middle management positions (because they had lower concerns of financial problems and had higher education and job ranks); (3) the participants had physical and mental health based on medical reports. The interviews were conducted in person and by the researcher in the Oil Company. The day and time of telephone and in-person interviews were determined by the participant’s agreement. The interviews were conducted from May to September 2021 in Tehran. Each interview began after the researcher established rapport with the participant. Additional questions were also asked to resolve and clarify any ambiguity in the participants’ statements. The time of interview with each couple lasted from 50 min to 75 min. After the interviews, their content was transcribed, and the collected data were analyzed. The transcripts were read carefully several times, the same for extracting reviewed codes. The open questions based on the topic of the research were developed as follows:
1. How do you view and define psychological wellbeing?
2. What strategies do you adopt to improve your psychological health after retirement?

Data analysis
The data were analyzed using Strauss & Corbin’s (1998) approach in three stages of open, axial, and selective coding. Data analysis was conducted simultaneously with data collection. To this end, after each interview, the previously collected data were compared with the new data to discover similarities and differences (Strauss & Corbin, 1998). During this phase, all interviews were transcribed, and recurrent codes were identified. The 3-way interaction was used to increase the internal consistency and credibility of the data. Triangulation refers to the search for consistency in the findings from different observers, tools, and observation methods at different times, places, and situations. A good inter-rater agreement between the researchers in codifying the data existed. A detailed and rich description was provided about the research context and the literature. 
To comply with the ethical considerations, the study procedure was explained to the participants in a briefing session. In addition, they were assured that the study results would be published as a general report without disclosing their personal information. They were also told they would be free not to attend the interviews and could leave the study at any stage if they wished. 

3. Results 
The study participants were 15 managers of the National Iranian Oil Company who were aged 60 to 65 years. They served in the top, senior, and middle management positions during their terms of office. Most participants had served for 30 years; the rest had 20 to 30 years of service records in the National Iranian Oil Company. A great percentage of the participants had a master’s degree or higher. It was tried to select the participants with greater diversity in terms of the geographical place of service and managerial positions, including human resources, business, technical development, production, IT, and exports (Table 1).

In Table 2, the factors affecting the promotion of mental health in old managers were divided into three categories, including self-coherence, the balance between life needs and satisfaction of the current situation; contextual factors promoting psychological health in older adults; and the process of achieving psychological health and wellbeing in older adults. 

Self-coherence and the Balance Between Life Needs and Satisfaction With the Current Situation
According to the participants, one of the most important factors promoting psychological health was self-coherence and the balance between life needs and satisfaction with the current situation, and feeling efficiency in the family and community. These themes were frequently detected in the participants’ statements. 

Feeling of efficiency in the community 
“When I could not find a job based on an expert, I can find a teaching career and share my knowledge and experiences with others, especially young people.” (Participant #7)

Feeling of efficiency in the family 
“My daughter obtained a board degree in Obstetrics and Gynecology. She had a medical office. My youngest daughter was ranked 55 on the university entrance exam and became a radiology specialist. They were here until last year and then went to France with their two daughters. Of course, our efforts were compensated because we raised two children with the highest academic levels.” (Participant #11)

Providing comfort and peace for older adults
“The first and most important thing is financial issues in the family. Financial problems in my family severely affect the physical health of the person and other family members.” (Participant #2)

Contextual factors promoting psychological health in older adults
The underlying factors were special factors that, according to the participants, had an impact on the promotion of their mental health. One of these factors was spirituality and religiosity.

Spirituality and religiosity
“I always say that we must thank God for having shelter and something to eat during this economic crisis and the COVID-19 pandemic. We have a shelter, and we are healthy.” (Participant #12)
The specific family circumstances in which they grew up, as well as their personality and temperament, were other underlying factors which led them to accept more adaptive strategies to cope with problems.

Specific family conditions and childhood personality 
“My mother was illiterate. However, I learned more things from my father. I also learned many things from my grandfather. I think this is related to genetic issues. He was a literate man who had written many things.” (Participant #9)

The existence of a law-abiding and disciplined society
“In a society like ours where there is no job security, no law, no funds, now one of the concerns of retirees of the oil company is how long our funds can last.” (Participant #2)

The process of achieving psychological health and wellbeing in older adults
Most participants considered satisfaction from occupational and professional performance and honesty in the workplace as one of the most important reasons for achieving mental health.

Satisfaction from job and professional performance
“Because I did nothing wrong, I was not afraid of being exposed and caught red-handed. Thank God, I did not commit any violation.” (Participant #3)

Having hobbies and activities
“Well, I’m trying to make up for it. For example, I attended various training courses and tried to communicate with other people. I stay up late at night and study because I want to keep my memory active. I saw that many people get Alzheimer and I tried to keep myself active.” (Participant #10)

Attending social gatherings and meetings
“I try to participate in meetings and go on group trips with friends and family members.” (Participant #14)

Attitudes toward life and others 
“If you study more and gain knowledge and insight, you can define a philosophy of life for yourself.” (Participant #2)

Healthy behaviors and habits
“I often go hiking, but it’s very difficult on the treadmill. Of course, after the COVID-19 outbreak, I don’t go to the gym. I now exercise at home. In the morning, I have to spend about 45 min doing some exercises for my spine; otherwise, my life will be disrupted.” (Participant #2)
In the paradigm model (Figure 1), causal factors such as family, society, culture, individual abilities, and characteristics can make the person feel efficient and useful in society and family. These factors also contribute to providing comfort and peace for older adults. Some strategies can pave the way for other people, especially younger ones, to benefit from the abilities and expertise of older managers. Empowering older adults to participate in social gatherings and meetings can help to solve the medical and economic problems this group of people faces. It should be noted that some contextual factors, such as religiosity, spirituality, specific family conditions, and childhood experiences, can facilitate the adoption of these strategies. According to the participants, growing up in a family with educated members can foster healthy behaviors and habits in adulthood. Also, occupational and legal security in old age is one of the important and special factors that result in physical health and provide the elderly psyche. Satisfaction with occupational and professional performance can also be regarded as one of the mediating factors. Older adults who are satisfied with their professional performance can have a happier life because reviewing their memories, and working experiences can create values and motivate them.

4. Discussion 
The present research findings indicated that causal factors such as family, community, culture, individual abilities, and characteristics lead to a sense of efficiency and usefulness in society and family and contribute to comfort and peace of mind in older adults. An effective strategy is to provide a suitable context for other people, especially the younger ones, to benefit from the abilities and expertise of older managers, help older adults to participate in social gatherings and meetings, and solve medical and insurance problems with which they are faced. Underlying factors such as religiosity, spirituality, specific family conditions, and childhood experiences contribute to developing strategies for promoting psychological health. Doing a job and legal security in old age are two of the important and special factors that can promote the physical and mental health of older adults. Mediating factors such as satisfaction with occupational and professional performance, attitudes toward others and life, and gaining value and purpose in life can improve psychological health.
Most of the participants in this study stated that there should be suitable context so that they can present their shared experiences through training courses to the youths. They believed that this helped them feel like to be an efficient member of the community. Moreover, many participants stated that they helped charities, and this made them feel happy and satisfied. They were also willing to do voluntary activities even without being paid. They reported that these activities promoted their mental health and enabled them to live happier lives. Berk (2017) found that most older adults have much time for leisure and voluntary activities when they retire. Singh et al. (2010) examined factors affecting mental health in older adults and showed that perceived self-efficacy is associated with increased mental health. Consistent with the findings of this study, Berk (2017) pointed out that the withdrawal of older adults from social activities is not their preference; rather, it indicates the inability of the social world to provide opportunities for their engagement in social activities. The more social opportunities are available to elderlies, the more they will believe that they can enjoy valuable experiences for themselves. These social opportunities help older adults share their knowledge and experiences with younger people. Gerino et al. (2017) also showed that the active participation of older people in social activities could be increased through special initiatives aimed at the older adult population. Another important point is that many participants are more willing to spend time with their friends than their families. Old age is no longer a time to be anxious and preoccupied with children’s problems, which may even exist in older managers. Instead of trying to solve the problems of their children and others, they need free time to handle their personal affairs. Perhaps it is essential to make people understand that children should gain independence so that they can decide on and solve their problems without relying on their parents because perhaps one of the biggest challenges faced by older adults is the problems of children.
On the other hand, the effect of education on mental health at older ages with formal education has been studied, and it has been shown that education acts as a predictor of healthy aging (Khodabakhshi-Koolaee, 2016). Education positively affects cognitive variables, including life satisfaction (Kavé, et al., 2012; Foverkof et al., 2018). As participants pointed out, one of the underlying factors is growing up in an educated family, which helped them use more adaptive strategies, such as studying and working on life’s problems, which led to their success in their older ages. Education is a central factor in improving social participation and allowing elders to appreciate their positive wellbeing as they age (Boulton-Lewis, Buys, & Lovie-Kitchin, , 2006). Consistent with the findings of this study, other studies (Bent et al., 2006; Hall, Rubin, & Charnock, 2009) showed that engaging in social activities in old age and cognitively stimulating leisure also reduces the risk of Alzheimer disease and dementia as a whole by stimulating synaptic growth. Studies have also shown a significant relationship between mental disorders, being single, low economic status, and current smoking (Silva, Loureiro, & Cardoso, 2016). Belo et al. (2020) found that perhaps a higher level of education can lead to a better understanding of all the changes of aging (body, life, profession, etc).
Physical activity can prevent or reduce the risk of osteoporosis, type 2 diabetes, obesity, hypertension, stroke, heart disease, colon cancer, breast cancer, and depression (WHO, 2019). Previous studies showed a correlation between low levels of physical activity and symptoms of anxiety and depression in older adults living in the community (Hao, et al., 2019). Physical inactivity is the fourth leading risk factor for global mortality (WHO, 2019). In contrast, several studies have shown that physical activity protects against the onset of depression and anxiety (Schuch et al., 2018). Blanchet, Chikhi, and Maltais (2018) also indicated that physical activity could positively affect cognitive functioning and mental health in older, healthy individuals and possibly reduce the risk of developing dementia and depression. Han et al. (2015) showed that age, religion, housing status, economic status, entertainment, and hobbies were influential in old age. Also, in their research, Patrick et al. showed that religion and spirituality play an important role in the self-improvement of the elderly (Patrick, Carney, & Ebert, 2022). 
The quality of life is a complex concept that can be influenced by many factors in each period of life and is completely individualized and depends on personal understanding, which can cover several objective and subjective domains (Bowling & Gabriel, 2007). The situation of older adults is getting worse day by day due to the constant change in the structure of society. About two-fifths of the elderly population has no personal income. Thus, most older adults completely or partially dependent on others for their basic needs (Joshi, 2018).
Analysis of the participants’ statements indicated that the only hope and motivation of the older adults, their memories and achievements, can contribute to promoting their mental health. These factors are very important for those who have been in a difficult and risky professional management position. Older adults face different types of health, financial, physical, and mental problems which is why taking care of them must be a high priority (Joshi, 2018). Older adults need special amenities such as health care, nutrition, and a sense of belonging. The type and treatment services they receive depend largely on the family culture (Joshi, 2018). Freund and Ebner (2005) showed that in late adulthood personal goals, while still beneficial, are increasingly focused on maintaining strengths and avoiding weaknesses. Pac et al. (2019) confirmed the significant effects of physical exercise on the chances of experiencing a healthy old age. People who exercise have higher functional activity, are healthier, and have better opportunities to socialize, go out, or meet other people, so they are more likely to promote their health. Leisure helps people to promote their health and has a positive effect on their quality of life (Lambirini et al., 2018). Higher levels of social support are also significantly more negatively associated with adopting negative coping styles and predict fewer symptoms of loneliness and depression. Higher levels of social support are significantly associated with positive coping styles and predict less depressive symptoms (Chen, Alston, & Guo, 2019). Having an extra child, on average, has a protective effect against increasing depression and anxiety symptoms in later life for white mothers (van den Broek, 2021). These desirable characteristics in managers have been achieved in the long run, especially due to high levels of mental health in the workplace and how the National Iranian Oil Company interacted with employees during this period. 

5. Conclusion
The results of the present study indicated that factors such as family, community, culture, and individual abilities and characteristics could contribute to a sense of efficiency and usefulness in the community and family and enhance social welfare in older adults. To promote psychological health, older adults tend to use strategies such as giving advice to younger people, participating in entertainment programs for older adults, and following up and solving medical and insurance problems. Underlying factors such as religiosity and spirituality, family, and personality characteristics facilitate promoting mental health. The consequences of psychological health led to financial security, physical and mental health, and gaining values ​​and goals in life in old age. In future research, it is better to consider the opinion of the family members of the retired person to better understand his/her psychological health.
There are several limitations to our study. First, the study participants were not representative of all Iranian older adults. The participants were selected in Tehran and from the Iranian National Oil Company. The level of income of retirees of Oil and Gas Companies in Iran is higher than most of the other jobs. Second, the participants did not cover the retired elderly who lived in nursing homes or were single or widowed.

Ethical Considerations
Compliance with ethical guidelines
The study was registered in the Iran National Committee for Ethics in Biomedical Research with code of ethics IR.IAU.SRB.REC.1399.197. 

Funding
This article was extracted from the MSc dissertation of the first author, Department of Counseling, Faculty of Humanities and Social Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran. 

Authors' contributions
All authors equally contributed to preparing this article.

Conflict of interest
The authors declared no conflict of interest.

Acknowledgments
The authors would like to appreciate the officials in the National Oil Company in Tehran and the participants who cooperated closely with them.

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