Analysis of Characteristics, Methods of Suicide,and Clinical Outcomes in Elderly Suicide Attempters in South Korea by Age Subgroup

1. Introduction

Suicide is a major public health concern in many countries. Around 800,000 people die by suicide annually; in other words, one person commits suicide around the world every 40 seconds (World Health Organization). With the growth of the elderly population, suicide among the elderly has emerged as a serious public health issue. Research has shown that suicide rates generally increase with age [1, 2]. Upon analyzing a population aged 60 years or older in units of 5 years, a study by Shah et al. (2016) showed a tendency of the elderly suicide rate to increase during the following ages: from 60-64 to 90-94 years old in men, and from 60-64 to 85-89 years old in women [3]. Among age groups, suicide was especially prevalent in those aged over 70 of both sexes. [4]

Suicide in the elderly population is also an important public health concern in South Korea as the country has a rapidly aging population. In 2018, 14.4 % of South Korea’s population was determined to be $\ge$ 65 years old. Due to the rapidly aging population in Korea, seniors aged 65 or older in 2019 as it is expected to be 14.9%, 20.3% in 2025, and 46.5% in 2067 [5]. Furthermore, elderly age groups are more likely to attempt suicide than other age groups because of reasons such as bereavement after death of spouse or relatives, suffering from a chronic physical illness, and economic difficulties due to retirement and reduced income sources. It was found that about 30% of Koreans aged 65 or older have thought of wanting to die in the last year. [6] South Korea had the highest suicide rate among all Organization for Economic Co-operation and Development (OECD) countries in 2017, with 24.6 suicides for every 100,000 people [7]. Based on age group, the suicide rates in 2017 were 36.9 for every 100,000 people in their 60s, 62.5 for every 100,000 people in their 70s, and 83.7 for every 100,000 people in their 80s or older [8]. Compared to other OECD countries, the suicide rate in South Korea is two times higher in the age groups between 20 and 60, and three times higher among those in their 70s and 80s [9]. The suicide rate among the elderly is so high that it cannot be compared with other age groups. In Japan, which is known to have a relatively high suicide rate, the suicide rate per 100,000 people of those aged 65–74 and above 75 was 17.9. The suicide rate among the elderly was 14.6, which is much lower than that of 61.8 (65-74 years old) and 80.4 (75 years or older) in Korea [6].

With a view to prevent suicide in the elderly, several studies have been conducted to investigate epidemiological data or examine risk factors of suicide in said age group [10, 11, 12, 13, 14, 15, 16]. According to a study by Vadysinghe et al., 32.1% of the unnatural deaths of the elderly were because of suicide, and poisoning (59.6%) was the most common method of suicide. [17] However, with the increase in the average life expectancy and improvement of the health status of the elderly population, the elderly population may have to be subdivided into age groups for analysis. While there has been research on suicide in the elderly via age group subdivision, this research focused on identifying the risk factors of suicide attempts. Studies have shown that identification of the availability of lethal means of suicide and the management of such means is as effective in the prevention of suicide as the prevention of the suicide attempt itself [18, 19]. This study sought to further explore the suicide-related characteristics and clinical outcomes according to the methods of suicide attempt among elderly individuals who were admitted to the emergency department (ED) due to injuries from a suicide attempt. Furthermore, we analyze the results by subdividing the elderly into age-specific subgroups.

2. Methods

3. Results

1,537,617 cases were collected through the Emergency Department-Based Injury In-depth Surveillance, from which a total of 5,333 cases were enrolled in this research (Fig. LABEL:1). The subjects had a mean age of 75.1 years old, and consisted of 3,039 males (57.0%) and 2,294 females (43.0%). Among the subjects, 2,720 (51.0%) were in the age band of 65-74; 2,078 (39.0%) were in the age band of 75-84; and 535 (10.0%) were aged 85 and older.

Fig. 1.

4. Discussion

Through analyzing the general characteristics of elderly patients who were admitted to the ED due to suicide attempts, we have confirmed the general demographic characteristics of each age subgroup. The results showed that the proportion of women increased, and that of men decreased, from the 1st age group to the 3rd age group. Among the elderly patients who attempted suicide aged 85 or older, the proportion of women was 56.4%, while that of men was 43.6% (Table 1). However, the proportion of elderly men and women who died did not reverse as age increased, with 55.6% of men and 44.4% of women comprising those aged 85 or older who died (Table 3). This indicates that the incidence of suicide attempters—including cases of mortality and survival—was high in women, but more men died from their suicide attempts. According to the National Emergency Department Information System (NEDIS), 14,803 male (44.3%) and 18,648 female (55.7%) suicide attempters visited the ED of an emergency medical service institution in South Korea in 2018, indicating a higher number of female suicide attempters [20]. On the other hand, according to Statistics Korea, the number of deaths by suicide was 2,591 for men and 1,002 for women among those aged 65 or older; and 730 for men and 417 for women among those aged 80 or older. Considering that the ratio of men in the Korean population—among those aged 80 or older—is 30.6%, this indicates that both the ratio of suicide attempts and that of suicide attempt successes are higher in men [5]. In 2018, the incidence of suicide for every 100,000 people in South Korea was: 82.2 for men and 23.7 for women at age 65; and 138.5 for men and 37.3 for women aged 80 or older [21]. This indicates a difference of more than three times between men and women. Such a difference in the suicide and attempt rates of men and women are similar worldwide. According to a systemic review of 53 studies published in Europe and America between 2005 and 2015, men (36% of the studies) and the elderly (28% of the studies) commit suicide more frequently, while women (30% of the studies) and young people (17% of the studies) demonstrate a higher number of attempts and suicidal behavior. [22]. According to the analysis results of data from the WHO Mortality Database between 2004 and 2009, the suicide mortality rate of men aged 65–74 was 28.6, and that of women was 7.5; the suicide mortality rate for men aged 75 or older was 40.2, and that of women was 10.4 [1]. In a study of the general population of Andalusia, Spain, the prevalence of attempted suicide did not vary between the sexes, whereas the prevalence of deaths by suicide was three-fold higher among males than among females, and increased with higher age. [4]

As shown by the results of this study, for those aged between 65 and 74, the rate of injury was higher when the elderly visited the ED at evening time; when there was alcohol ingestion; and in outdoor places or commercial facilities. For those aged 85 or older, the rate of injury was higher when they visited ED during daytime; and in medical facilities, residential facilities, and houses. For those aged between 65 and 74, the following reasons for suicide attempt accounted for a high proportion of cases: psychiatric disease, conflict with family or others, and reasons related to tasks at the workplace. For those aged 85 or older, the following reasons for their attempt accounted for a high proportion of cases: the death of someone, and medical illness. The most common reason for suicide attempt by age group was psychiatric disease in individuals aged 65–74 years old, and medical illness in those aged 75–85. This may be because among those aged 65 or older, the 1st group is younger in comparison; thus, they are more physically active, have better health conditions, and more external and social activities. These are reflected in the findings of this study. For suicide attempts due to psychiatric disease, positive mental health was shown to moderate the impact of depression on suicidal ideation. Future studies on the suicide risk of elderly patients should consider the impact of positive mental health as well as psychiatric disorders [23]. An important characteristic of suicide among the elderly is that suicide attempts because of medical illness account for the largest proportion as the age increases. Even in the absence of psychiatric problems or terminal illnesses, most elderly individuals experience irreversible decline in physical function due to aging. For this reason, there is a high tendency of attempting suicide among the elderly. All humans undergo irreversible aging, which raises numerous ethical concerns regarding the acceptance of choosing to commit suicide. Whether to admit the rationale of suicide of the elderly should be further investigated in future studies, and clinicians should take the findings into consideration when dealing with elderly patients [24, 25].

In order to prevent suicide, a multifaceted approach is needed at the individual, relationship, community, and societal levels. Among these approaches, the societal level includes the identification of lethal methods of suicide and reducing access to such methods for persons at risk of suicide [19]. The effect of controlling the availability of suicide methods has been introduced in many previous studies— one of which reported that suicide via pesticide was reduced with the regulation of paraquat, a lethal poisoning agent [18]. On the other hand, it has been reported that pharmaceutical drug poisoning increased upon the approval of over-the-counter drug sales [26]. As can be seen from these examples, understanding the characteristics of the methods of suicide provides important basic data for establishing preventive measures. In this study, an analysis of the methods used by suicide attempters who visited the ED showed that there was no significant difference among the age groups aside from the method of collision. The suicide attempt method with the highest incidence in the entire patient group was substance exposure, which accounted for 79.2% of cases. In both the admitted group and the mortality group, substance exposure also accounted for the highest proportion (78.0% and 54.4%, respectively). In a number of studies, intentional poisoning has been reported to account for the majority of suicide attempts, and various analyses on this method have been conducted [27, 28, 29, 30, 31, 32, 33, 34, 35]. To prevent suicide in the elderly, efforts should be made to reduce the availability of substances that are fatal when ingested. To this end, the existing research should be referenced, and research on the patterns of substance exposure in each elderly age group should be conducted, based on which measures to reduce access to poisonous substances can be suggested.

Although substance exposure was identified to be the suicide attempt method with the highest incidence, it is also important to consider its association with poor clinical outcomes. A subgroup analysis based on admission status and mortality showed that in the case of substance exposure, the ratio was higher in the discharge group than the admission group, and in the survival group than the mortality group. The adjusted OR for admission with regard to substance exposure was 0.617 (95% CI 0.459-0.829) for the age group of 75-84; and the adjusted OR for mortality was 0.253 (95% CI 0.459-0.829) for the age group of 65-74; 0.271 (95% CI 0.210-0.349) for the age group of 75-84, and 0.220 (95% CI 0.135-0.360) for the age group of 85 or older. On the other hand, in the case of drowning/hanging/asphyxia and fall/slip, their proportion in the admission group and the mortality group was high. Through multivariate analysis, drowning/hanging/asphyxia was identified as a significant risk factor of admission in all groups, while slip/fall was identified as a significant risk factor in the 65-74 and 75-84 age groups. The risk factors of mortality also showed similar results. In all groups, drowning/hanging/asphyxia and slip/fall were analyzed as risk factors. Among all suicide attempt methods, these two are deemed to be the most fatal methods which tend to cause admission and mortality. This is confirmed by suicide status data. In 2018, the means of suicide with the highest resulting suicide rate was hanging—with a rate of 13.9 for every 100,000 persons—while the means with the second highest rate was falling, with a rate of 4.4 for every 100,000 persons [36]. Caregivers of elderly individuals who are at risk of attempting suicide should be educated about fatal suicide methods, such as drowning, hanging, asphyxia, and fall/slip. Preventing suicide among the elderly also requires social awareness of installing physical devices or controlling the surrounding environment.

According to reports, firearms are widely used as a means for suicide among the elderly [37, 38]. In particular, the use of firearms is the most lethal suicide method among American males [39]. Since private gun possession is not allowed in South Korea, however, the penetration rate of firearms is low in the country. Thus, the use of firearms or a gunshot was not included as a means of suicide in this study. Such differences can be attributed to characteristics unique to each country.

Furthermore, the psychosocial stressors for each age group in this study were different. This shows that stressors are different depending on the age band, although all subjects were aged 65 or older. It has been reported that stressors have a risky effect on fatal suicidal behaviors [40]. Ultimately, the elderly should not simply be regarded as a single group, but approached differently for each age band.

There are several limitations in this study. First, as the data was collected from all EDs nationwide, it is highly probable that self-injury or suicide patients were classified as “others or unknown” in the “intentional injury” category despite the review of data upon being sent. In particular, there are cases where the patient is unable to respond, such as in cases of death, or where he or she may have become incapable of expressing his or her intentions. In such cases, it is possible that mortality due to suicide was classified as “intentionality unknown.” Second, a single case of injury was collected per patient. In cases where the patient has attempted suicide multiple times and through multiple methods, data were collected only for the method which was judged to have had the most significant impact on the prognosis of the patient—which may lead to biases in the data. It was not possible to analyze the risks that could appear when multiple attempt methods were used. In addition, since the data consists of injury data from the ED, the sociological factors relating to suicide have not been investigated in the study, which may be another limitation.

5. Conclusions

Through the analysis of the general characteristics of elderly patients who were admitted to the ED due to suicide attempts, we confirmed the general demographic characteristics of each age subgroup. With regard to suicide attempt methods, substance exposure was the most frequent method across all age groups. However, it was not a significant factor of admission and mortality. Drowning, hanging, and asphyxia were identified to be significant factors of admission and mortality in all groups aged 65 or older. Further, the fall/slip method was identified as a high risk factor of admission for patients under 85, and is a significant mortality factor for all subgroups. In particular, the fall/slip method showed significantly high lethality in patients aged 85 or older. Therefore, to prevent suicide among the elderly, it is necessary to reduce their access to drugs and to monitor and physical obstruction devices for fatal methods.

Acknowledgments

We would like to thank Hye Ah Lee for advice on statistical analysis.

Conflicts of Interest

The authors declare that there is no conflict of interest regarding the publication of this article.

Author contributions

DH Lee & JH Lee designed the research study, analyzed the data, wrote the manuscript equally. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript.

Funding information

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No.2018R1C1B5046096), and a fund by Research of Korea Centers for Disease Control and Prevention (Emergency Department-Based Injury In-depth Surveillance). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Ethics approval and consent to participate.The KCDC is the authority for accessing the data. Informed consent was waived by the IRB because patient information was anonymized before the analysis.