Suicide in the Global Chinese Aging Population: A Review of Risk and Protective Factors, Consequences, and Interventions

: As one of the leading causes of death around the world, suicide is a global public health threat. In the Chinese population, suicides constitute one-fifth of all recorded suicides in the world. Despite the factual data on suicide rates, the understanding of various causal factors behind suicide, including risk and protective factors and adverse health care, remained incomplete among the global Chinese aging population. To fill in the knowledge void, this paper reviews the epidemiology of suicide among Chinese older adults globally as well as explores the existing intervention strategies. Using the PRISMA statement, we performed a systematic review of exiting research on the topic, including studies describing suicide among Chinese older adults in communities outside of Asia. A literature search was conducted online by using both medical and social science data-bases. Our findings highlighted that elderly suicide in Chinese populations is significantly affected by the social, cultural, and familial contexts within which the individual lived prior to committing suicide. Reviewing such research indicated that while reducing risk factors may contribute to lowering suicides amongst Chinese older adults, measures to improve protective factors are also critical. Support through ongoing family and community care relationships is necessary to improve resilience in older adults and positive aging. Future longitudinal studies on the risk factors and protective factors, and adverse health consequences are called for to devise culturally and linguistically appropriate prevention and intervention programs in global Chinese aging populations.

Aging and Disease • Volume 6, Number 2, April 2015 122 among the U.S. Chinese women aged 75-84 years; and 10fold higher suicide rate among the U.S. Chinese women over age 85 compared to white women of the same age groups [4]. Despite the factual data on suicide rates, the understanding of various causal factors behind suicide, including risk and protective factors and adverse health care, remained incomplete. In the U.S., Chinese older immigrants have been identified as an underserved group with low acculturation level and high cultural and social isolation. Prior studies suggest that there are significant health disparities among Chinese persons, including chronic diseases, cancer screening and treatment, and psychological distress after having relocated and losing contact with their native support network [5]. In addition, Chinese immigrants experience more pronounced migratory and psychosocial distress, which is further exacerbated by the vast cultural and linguistic barriers, as well as physical frailty and stressful life events [6]. The psychological distress experienced by this population imposes significant health related consequences, and further impedes the quality-of-life of Chinese older adults.
Therefore, this paper aims to illuminate factors specific to the Chinese immigrant aging population through reviewing the epidemiology of suicide amongst this group. Ultimately, this review study aims to bring new insights on cultural and contextual factors unique to Chinese aging populations in the U.S. and worldwide.

Literature Search
The purpose of this article is to provide a critical review of the research on the epidemiology of suicide among Chinese older adults, including risk and protective factors, health consequences associated with suicidal ideation, attempts and behaviors, as well as to suggest directions for future research and ways to improve care for the Chinese aging population.
The study design was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies eligible for inclusion in this review were studies assessing suicide risk and protective factors, and adverse health outcomes associated with suicidal behaviors among Chinese older adults in diverse communities, including Chinese elderly in China, as well as overseas Chinese communities. As such, original research articles related to Chinese aging populations around the world were included. The search was limited to studies available in full-text, and written either in English or in Chinese. Manuscripts published over 2 decades ago (pre-1990's) were excluded.

Risk Factors Associated with Suicide
We reviewed evidence on risk factors for suicidal ideation and suicidal behaviors. Given the inherent diversity among global Chinese communities, we presented the findings according to different geographic regions (

Demographic Risk Factors
Research on elderly suicide in China reveals several specific findings. For instance, older age and female gender were associated with increased suicidal behavior. Interestingly, while most studies reported that the risk of suicide increases with age [7], one study in metropolitan China revealed that younger age was associated with higher odds of suicidal ideation [8]. Research also shows that the urban/rural divide poses as a risk factor for suicide; those living in Northern China and in rural areas were found to be at a higher risk of suicide [9]. In addition, social status was found to predispose individuals to a greater risk of suicide and lower education was suggested to increase the risk of suicide. Furthermore, financial constraint is evidenced as a main influencing factor for suicidal ideation and behavior [10].

Psychological and Social Risk Factors
A significant correlation exists between depressive symptoms, suicide attempts, and suicide mortality among Chinese older adults. Depressive symptoms have been associated with previous suicide attempts. Negative events in family life and social well-being, including a number of stressful events and life changes were also found to be relevant to suicide [11]. In addition, researchers have begun to examine specific forms of psychological distress that are associated with suicidal behaviors. As such, the loss of a partner and feelings of hopeless may both increase distress to a point that a senior person feels that life has become unbearable and in turn, seek suicide.
Regarding social risk factors, the experience of severe interpersonal conflict before death is associated with previous suicidal behavior. Having relatives, friends or associates with suicidal behavior was also found to increases the risks for suicide [12;13]. One qualitative study with older veterans in Taiwan reported that family conflict also triggers suicidal behavior [14].

Psychiatric Risk Factors
The presence of a psychiatric disorder is among the most consistently reported risk factors for suicidal behavior.
Researchers have begun to examine more specific constructs that may explain exactly why psychiatric disorders are associated with suicidal behavior. Several such risk factors include mood, anxiety, bi-polar, and other mental disorders [15;16].

Biological Risk Factors
Genetic association studies have suggested that genes including serotonin transporter, tryptophan hydroxylase 2, and brain-derived neurotrophic factor are related to suicide behaviors. However, most research in Chinese elderly or adult populations did not report the associations and some researchers speculated that the relevance of genetic factors could be ethnicity dependent [17]. When Hwang et al. [18]

Other Factors
The list of risk factors outlined above is not exhaustive, and there is emerging evidence suggesting a range of other correlative factors. Research in Hong Kong found associations between SARS and adult suicide rate [20;21]. In addition, physical health including chronic illness and physical disabilities, were also found to increase the Aging and Disease • Volume 6, Number 2, April 2015 126 likelihood of suicide. As such, improvement in the ability to predict suicidal behavior through the continued identification of specific risk factors represents one of the most important directions for future studies in this area.

Consequences Associated with Suicide
Evidence suggests that suicide mortality increases the years of life lost and disability-adjusted life years lost (Table 4). In Taiwan, research suggests that suicide deaths in older adults account for 28.9% of total suicide deaths, representing 12.4% of the total population [22]. In Hong Kong, the total years of life lost due to suicide increased by 96.0% in 30 years, from about 9,900 years in 1981 to 19,400 years in 2001 [23]. Over time, suicide behaviors could lead to increased hospitalization, including prolonged stays in an intensive care unit, in addition to further suicide attempts, and also completed suicides (12.9-39.6 folds risk) [24]. It was reported that most suicide attempts and completed suicide deaths were associated with past histories of suicide attempt(s). In a study of elderly suicides in 279 communities, 68% indicated suicide ideation before their fatal acts [25].

Interventions in Chinese Elderly Suicide
Understanding the interactive relationship between risk and protective factors in suicidal behavior and how the interaction can be modified are challenges to suicide prevention and intervention. In addition, suicide intervention is a relatively under-researched area among Chinese elderly. There have been several suicide prevention and intervention programs initiated to serve this population, but evidence is limited on the effectiveness of prevention and intervention programs ( Table 5).
The Chinese Association of Mental Health (CMHA) has recently set up a suicide prevention committee that offers counseling services over telephone hotlines. However, due to the large population size and limited man power, its effectiveness remains to be seen. The Hong Kong SAR has taken an alternate approach through the Opportunities for the Elderly Project (OEP). Reaching out to older adults with high risks of suicide through early detection and screening, OEP fosters a sense of community to care for the elderly population [26]. Another government-funded multifaceted model including treatment of depression, gatekeeper training, aftercare for suicide attempters, and care management also shows evidence of reducing suicide rates of completed suicide in old-age suicide attempters [27].
Elderly suicide intervention programs were also implemented in international Chinese communities. In Singapore, early detection and public awareness were widely publicized through media. Primary care and specialized care for those older adults experiencing high risk factors is also provided. In addition, community support is reinforced through the Center for Enabled Living (CEL), a multi-disciplinary community case management program. The Center helps connect individuals to different community resources and also provides hotline services for the elderly in crisis [28].

Discussion
Among the Chinese elderly population factors such as, older age, female, living in rural area, depressive symptoms, previous suicide attempts, negative life events and medical complications were found to correlate strongly with suicide completion. Alternatively, high levels of self-esteem, living with children, and high Instrumental Activities of Daily Living (IADL) score were found to be protective factors. Suicide attempts could lead to hospitalization, a 12-33 fold increase in risk of completed suicide, and potential detrimental effects to loved ones.
Several issues relating to the unique risk factors in Chinese communities warrant further attention. First, with respect to age distribution in China, high incidence of older adult suicides is dissonant to important Chinese traditional values of filial obligations of respect for older adults. Confucian philosophy has strongly influenced Chinese lifestyle and social interaction for thousands of years. However, in the face of rapid industrialization, modernization and social-cultural changes brought about by economic reforms, family structures and support may undergo significant transformations, potentially resulting in older adults perceiving insufficient filial support and care. Whereas stressful life events including family conflicts were found to be an important risk factor to suicide, the importance of familial integration cannot be overemphasized. Providing a sense of community and social support to the vulnerable older adult may serve as a buffer against suicide risks.
In addition, rural older adults may be at higher risks of suicide compared to their urban counterparts. Suicide in China has been historically perceived as a final act in response to social distress [29]. Given that many believe traditional values and practices to be more deeply-rooted in the countryside, the importance of such beliefs warrants particular attention. Effects of economic reform, poverty, cultural changes and the one-child policy may all contribute to the phenomenon.
Aging and Disease • Volume 6, Number 2, April 2015 127 Furthermore, cultural considerations in suicidal behaviors of overseas Chinese elderly immigrants should also be noted. It was reported that more than 80% of Chinese older adults were foreign born and more than 30% of Chinese older adults immigrated after the age of 60. Suffering from the loss of tradition, lack of acculturation and aging, the older Chinese population in the U.S. often lives in isolation, far away from their families in China. Hindered by cultural and language barriers, they experienced much difficulty in communication with others, let alone the ability to seek help. Therefore, it was not surprising that studies suggested that older Chinese immigrants have poorer quality of life than the national norms [30]. Other studies also pointed out that the prevalence of depressive symptoms among Chinese older adults was higher than that of general aging population in North America [31]. Coupled with the increasing social stressors and culturally valued imperatives of maintaining personal honor, older adults may consider themselves as "burden" to their families, and thus opt to suicide as means to resolve conflict.

Implications
Suicide among the Chinese elderly is an important public health issue. Current research highlights that elderly suicide is deeply affected by the socio, cultural, and familial contexts within which it takes place. With respect to prevention and intervention strategies, educational outreach through programs targeted to Chinese older adults with suspected suicidal inclination or risk factor of suicide, may serve as an effective measure. Early detection and prevention of elder suicide is necessary. In addition, mental health and health professionals at the front line should consider outreach programs that are particularly designed to increase familial, social, and community support for vulnerable older adults. Medical professionals should also consider screening older patients for suicidal risk factors by integrating questions on suicidal thoughts into routine medical history questions for older adults.
These findings have important implications not only for geriatricians, but also for multiple disciplines that work with older adults with suicide risk. Other relevant disciplines such as nursing, social work, and social services agencies are also in unique positions to identify and intervene on predisposing factors that might lead to completed suicide. Direct suicide prevention strategies with culturally and linguistically sensitive services including hotlines and counseling programs should be expanded.
In addition, our review findings call for improved health and social welfare programs for the older adults, particularly for those in the rural areas and those that lack of financial support. Whereas reducing risk factors may contribute in lowering suicides, measures to improve protective factors are also critical. The prevention of elderly suicide needs to be a joint effort by family members, and communities at large. Support through ongoing family and community care relationships is necessary to improve resilience and positive aging.

Conclusion
In sum, Chinese older adults reported the highest suicide rate in the world. This statistic is the result of multiple factors including biological, social, economic, and cultural contexts, and should be given high priority with regard to prevention, intervention and research. Rigorous research on the prevalence of suicidal ideation, attempts and plans in different Chinese aging population are urgently called for. Future longitudinal studies on the risk factors and protective factors, and adverse health consequence will be useful to devise culturally and linguistically appropriate prevention and intervention programs.

Funding Support
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