Engagement in productive activities and suicidal ideation among female older adults in South Korea

Abstract Despite the rapid increase in the older population in South Korea, the quality of life of older adults remains low. The suicide rate of older adults in South Korea is among the highest of all OECD countries. Using data from 2012 (wave 4) to 2020 (wave 8) of the Korean Longitudinal Survey of Women and Families (KLoWF), this study examined the effects of participation in productive activities on suicidal ideation among South Korean female older adults. This study derived three key findings. First, although there were differences regarding the type of productive activity, participation in productive activity could reduce the probability of experiencing suicidal ideation. Participation in housework as a productive activity related to daily life had the greatest marginal effect. Second, the more productive activities one participated in, the lower the likelihood of suicidal ideation. Third, the economic and health status of older women had a significant effect on suicidal ideation. The marginal effect of health status was greater than that of economic status. This study not only makes an academic contribution but also has policy implications for the field of public health.


Introduction
The growth of the older population has been accelerating in developed countries, and population aging in East Asian countries has been progressing at a dramatically accelerated speed.Japan, known as the world's oldest society, has already become a super-aged society.In 2019, Japan's population aged 65 and over accounted for 28% of the total population (United Nations, 2019).In China, the older population is also rapidly increasing.In 2018, the number of Chinese older people aged 65 or older exceeded 160 million (National Bureau of Statistics of China, 2019).In particular, South Korea has been attracting worldwide attention with an unprecedentedly fast rate of population aging.In 2021, the population aged 65 and over in South Korea accounted for 16.5% of the total population.South Korea became an aged society in 2017 and is expected to become a super-aged society by 2025 (Statistics Korea, 2021).
Despite the rapid increase in the older population in South Korea, the quality of life of older adults is relatively low (Chung et al., 2017;HelpAge International, 2015).The suicide rate of older adults in South Korea is among the highest of all OECD countries.Although the suicide rate of South Korean older adults aged 65 and over is on the decline, it still ranks first among OECD countries.In 2019, the suicide rate of older adults in South Korea was 46.6 per 100,000 people, far exceeding the OECD average (17.2).Additionally, as the age of older adults increases, the suicide rate also increases, with the figure rising from 33.3 for people in their 50s, to 33.7 for those in their 60s, 46.2 for those in their 70s, and 67.4 for those in their 80s and older (Of Health & Welfare, 2021).South Korean society has experienced the fastest increase in the older population in the world; however, there is an urgent need for investigation due to the low quality of life and high suicide rates among the older population.
As the suicide phenomenon concerning older adults has emerged as an important social problem in South Korea, related studies have steadily accumulated to analyze types of suicide in older adults or identify risk factors for suicide (H. S. Kim, 2000;Kang & Moon, 2013;M. R. Kim, 2010;S. H. Kim & Choi, 2007).However, the existing studies have some limitations.Firstly, previous studies on suicide and suicidal ideation among older adults have focused on suicide risk factors.They have revealed the effects of individual psychological characteristics such as depression, socioeconomic characteristics, and health characteristics on suicide among older adults (Bae et al., 2005;H. S. Kim, 2000H. S. Kim, , 2002;;M. R. Kim, 2010;S. H. Kim & Choi, 2007).Also, some existing studies have identified that participation in social activities such as in clubs or organizations, and engagement in hobbies and volunteer activities could be a crucial factor to reduce suicidal ideation (M.I. Kim & Shin, 2013;M. J. Park, 2009Yi & Lee, 2009).However, little attention has been paid to the relationship between productive activities and suicide ideation among older adults.As activities that create economic and social values, productive activities are somewhat different from social participation, which has a more general meaning of participation.Moreover, as existing studies have mainly focused on the suicides in older adults living independently (Song et al., 2010;Yang & Ju, 2011) or male older adults (Park & Lee, 2013;K. D. Kim, 2016), there is a lack of research on the suicides of the female older adults.Finally, since most related studies have used crosssectional data, it was difficult to identify the causality.There is a lack of related studies performing longitudinal analyses.
To address these gaps in the literature, this study explores the effect of participation in productive activities on suicidal ideation among South Korean female older adults.Suicidal ideation refers to "thoughts serving the agent of one's own death".The seriousness of suicidal ideation might vary depending on the specificity of suicide plans and the degree of suicidal intent (American Psychiatric Association, 2003).Suicidal ideation as a pre-stage of suicide attempt or completed suicide is highly associated with suicide attempt or completed suicide (Beck et al., 1979;Bonner & Rich, 1987;Conwell et al., 2002;Lester, 1989).Therefore, identifying the factors that affect suicidal ideation would contribute to reducing suicide rates.
This study examines economic activity, education and training, housework, and caretaking as productive activities of older adults.Productive activities refer to "the capacity of an individual or population to serve in the paid workforce, to serve in volunteer activities, to assist in the family, and to maintain himself or herself as independently as possible" (Butler & Malvin Schechter, 1995).Otherwise stated, it refers to a series of activities in which older adults create not only economic but also social value through participation.Existing studies have revealed that participation in productive activities has a positive effect on the psychological well-being of older adults (Baker et al., 2005;Cavan, 1962;Herzog & House, 1991;Matz-Costa et al., 2014).According to activity theory and role theory, life satisfaction can increase as older adults participate in various activities (Lemon et al., 1972), and participation in meaningful social roles and productively active roles can offer a sense of identity and improve quality of life in old age (Baker et al., 2005;Havighurst & Albrecht, 1953).Occupying roles can allow the formation and maintenance of social networks and have a positive effect on self-perception and behavior by increasing the possibility of receiving social support in times of need (Moen et al., 2018;Verbrugge, 1983).Therefore, participating in productive activities might be likely to reduce the probability of suicidal ideation among older adults.
This study focuses on suicidal ideation among South Korean female older adults.In South Korea, although the completed suicide rate of male older adults is higher than that of female older adults, the suicidal ideation rate of female older adults is higher (Lee et al., 2020).Therefore, there is a need for continuous interest and research on the suicides of older women in Korean society.This study examines the effects of participation in productive activities on suicidal ideation among South Korean female older adults.

Data
This study used data from 2012 (wave 4) to 2020 (wave 8) of the Korean Longitudinal Survey of Women and Families (KLoWF) to analyze the effects of engagement in productive activities on suicidal ideation.Suicidal ideation was only investigated in the 4 th to 8 th waves of KloWF.This survey was a nationally representative longitudinal study of women aged 19 years and above.Questions related to individual characteristics, career, and family life were included.The first survey was conducted in 2007 and the second survey was conducted in 2008.It was then conducted every two years and completed by the 8 th survey in 2020.This study was based on South Korean female respondents aged 50 to 74 who were able to mostly maintain their physical functions and activities.The final sample included 6,100 individuals and 21,213 observations.

Measures
In this study, suicidal ideation among female older adults was the dependent variable.This was measured by asking respondents, "Have you experienced suicidal ideation in the past year?"The answer was coded as 1 = yes or 0 = no.Productive activities such as economic activity, education and training, housework, and caretaking were included as independent variables.Economic activity was measured using the question, "Are you currently working to earn an income?"Education and training was measured using the question, "Over the past year, have you received or are you currently receiving training for self-development, employment, or vocational skills development?"For housework, subjects were asked how often they participated in (1) preparing meals and cooking, (2) washing dishes, (3) washing clothes, (4) grocery shopping, and (5) cleaning the house.Subjects selected from the following responses: 1 = Almost every day, 2 = 4-5 days a week, 3 = 2-3 days a week, 4 = 1 day a week, 5 = rarely, 6 = not at all.For the analysis, not participating in any housework was coded as 0 and participating in one or more housework was coded as 1.For caretaking, subjects were asked how many hours of caretaking activities they conducted per day to take care of children, parents, or sick household members.Each productive activity was included in the analysis model as a dichotomous variable.The answer was coded as 1 = participation and 0 = no.Number of activities was coded from 4 (participating in economic activities, education and training, housework, and caretaking) to 0 (participating in no activities).
Age, marital status, number of household members, education level, economic status, and health status were included as control variables.Marital status was coded as 1 = the presence of a spouse (married) or 0 = the absence of a spouse (single/divorced/widowed/separated).Number of household members was measured by asking subjects how many members were in their household.Education level was measured by years of schooling.Economic and health status were measured from 1= very good to 5 = very bad.

Analytical strategy
First, a descriptive analysis was conducted with the variables used in the analysis presented (see Tables 1 and 2).Next, using panel data, a correlated random effects probit model was used to examine the effect of participation in productive activities on suicidal ideation among female older adults in South Korea.A correlated random effects probit model can identify both intra-individual changes and inter-individual differences.Here, the dependent variable was a dichotomous variable with a value of 1 = experienced suicidal ideation or 0 = did not experience suicidal ideation.Although nonlinear models such as logit or probit models are generally used in such cases, the use of a fixed-effect logit model to solve an endogeneity problem can also cause other problems related to convergence or incidental parameters (Lancaster, 2000;Wooldridge, 2010).Therefore, this study uses a correlated random effects probit model proposed by Mundlak (1978) and Chamberlain (1984) to solve endogeneity problems more easily.And, since the dependent variable is a dichotomous variable, unlike the linear model, the coefficients do not mean marginal effects.Therefore, the average marginal effects along with the coefficients were also estimated to facilitate interpretation.Stata 17 was used to analyze data.

Results
Before presenting the results of the correlated random effects probit model, a descriptive analysis was performed.Table 1 shows the respondents' characteristics from waves 4 to 8. Table 2 presents the cross-tabulation between participation by type of productive activity and suicidal ideation for all observations.There was a significant relationship between participation in economic activities and suicidal ideation.A total of 5.6% of respondents who did not participate in economic activities had experienced suicidal ideation and 3.4% of respondents who participated in economic activities had experienced suicidal ideation.A total of 4.4% of respondents who did not participate in education and training and 1.8% of respondents who participated in education and training had experienced suicidal ideation.A total of 21.4% of respondents who did not participate in housework had experienced suicidal ideation.Compared to other productive activities, participation in housework seemed to be closely related to suicidal ideation.Economic activities, education and training, and housework had a statistically significant relationship with suicidal ideation.However, there was no significant relationship between caretaking and suicidal ideation.
The results of analyzing the correlated random effect probit model predicting suicidal ideation among South Korean female older adults are presented in Table 3.As shown, participation in productive activities generally reduced the likelihood of experiencing suicidal ideation.Respondents who participated in economic activities were less likely to experience suicidal ideation than those who did not participate in economic activities.Additionally, it can also be interpreted that the probability of suicidal ideation decreases when the condition changes from not participating in economic activities to participating in economic activities, since this study analyzed the random effect probit model.Participation in housework also had a significant impact on suicidal ideation.The effect of participation in housework on suicidal ideation was particularly remarkable.
Compared to those who do not participate in housework, respondents who participate in housework were less likely to experience suicidal ideation.Likewise, when the state changed from not participating in housework to participating in housework, the possibility of experiencing suicidal ideation was reduced.However, the effect of education and training, caretaking on suicidal ideation was not statistically significant.Table 3 also shows the effect of the number of productive activities participated in on suicidal ideation.As the number of productive activities increased, suicidal ideation tended to decrease.Of the control variables, the effects of economic and health status on suicidal ideation were noticeable.The worse the economic conditions of respondents, the higher the probability of experiencing suicidal ideation.Additionally, the worse the health status of respondents, the higher the likelihood of experiencing suicidal ideation.The average marginal effect (AME) of health status was greater than that of economic status.

Discussion and conclusion
The suicide rate of older adults in South Korea is the highest among OECD countries.Despite the unprecedented rapid pace of population aging in South Korea, the quality of life of older adults remains low.This study focused on South Korean female older adults, who have been relatively neglected in suicide-related studies.Additionally, although existing research has examined the predictors of suicide or suicidal ideation, little attention has been paid to the effects of productive activities among older adults.To address these gaps, this study investigated the effects of participation in productive activities on suicidal ideation among South Korean female older adults.I conducted a panel analysis using data from waves 4 to 8 of KLoWF.
In this study, I derived three main findings.First, although there were differences regarding type of productive activity, participation in productive activity generally reduced the probability of experiencing suicidal ideation.The effect of economic activity and housework on suicidal ideation was remarkable.Participation in housework as a productive activity related to daily life had the greatest marginal effect.Second, the more productive activities one participated in, the lower the likelihood of one experiencing suicidal ideation.Third, besides productive activities, the economic and health status of respondents had a significant impact on suicidal ideation.The impact of health and economic conditions on suicidal ideation has also been shown in previous studies (Breslau, 1992;Ingersoll et al., 1993;Kandel et al., 1991;Kessler et al., 2005;Paykel et al., 1974).In this study, the marginal effect of health status was greater than that of economic status.
The Korean government has made various efforts to reduce the suicide rate.In particular, the 4th National Suicide Prevention Plan (2018-2022) focuses on strengthening screening for depression in the older adults as well as implementing of mental health programs and friend-making projects for the older living alone (Ministry of Health & WelfareSouth Korea, 2018).However, more policy efforts are required to reduce suicide in older adults, especially female older adults.This study has several policy implications.The results of this study show that the influence of housework is important regarding suicidal ideation among South Korean female older adults.Participation in housework is closely linked to activities of daily living (ADL) and instrumental activities of daily living (IADL).Participation in housework is possible when the female older adults can activity their own and perform their functions in their daily lives.Therefore, it is necessary to prepare an effective program to enhance the quality of life of older adults by improving physical function and health status.Additionally, considering the impact of participation in economic activities and economic status on suicidal ideation, policy alternatives are needed to increase the amount and quality of jobs available so that female older adults can participate more actively in economic activities.Moreover, various programs related to jobs, education and training, and volunteer activities in the community are required.Such community programs could help female older adults participate in more diverse productive activities.
This study also has academic contributions.Firstly, this paper is significant in that it attempted to explain suicidal ideation among female older adults through the perspective of productive aging.Secondly, it contributes to suicide-related literature and the public health field since this study targeted respondents in South Korea, which has the highest suicide rate for older adults in the world.Finally, studies related to suicide among older adults in South Korea have largely focused on male older adults or older adults living independently.This paper addressed these gaps in the literature by investigating suicidal ideation among female older adults.
Despite these contributions, this study has some limitations.First, although this study examined the effects of productive activities on suicidal ideation among female older adults, since it targeted respondents in South Korea, it is necessary to examine the relationship between productive activities and suicidal ideation in other countries in future research.Moreover, further research might need to understand socio-cultural differences in behaviors in aging population worldwide.For example, Japanese people have the concept of Ikigai and such cultural concept might anchor certain type of psychological and behavioral tendencies among the Japanese elderly.Second, this study considered four types of productive activity, including economic activity, education and training, housework, and caretaking.However, more activities such as volunteering could be investigated in future research.Third, further research needs to examine the relationship between various productive activities and suicidal ideation through a comparison between female and male older adults.You are free to: Share -copy and redistribute the material in any medium or format.Adapt -remix, transform, and build upon the material for any purpose, even commercially.The licensor cannot revoke these freedoms as long as you follow the license terms.
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a
compared to the single/divorced/widowed/separated (the absence of a spouse); b compared to no participation; c compared to no participation; d compared to no participation; e compared to no participation *p < 0.05; **p<0.01;***p<0.001

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Table 3 . The Results of the Correlated Random Effects Probit Model Predicting Suicidal Ideation among South Korean Female Older Adults Coefficient Marginal Effect Coefficient Marginal Effect Control variable
Marginal effects are average marginal effects (AME).Robust standard error is in parentheses.