a b s t r a c t

Background: The emergency department (ED) is one of the first gateways when suicide attempt patients seek health care services. The purpose of this study was to analyze the hypothesis that people who received emer- gency psychiatric services in previous suicide attempts will have a lower mortality rate in current ED visits owing to subsequent suicide attempts.

Method: This retrospective study included patients who visited six EDs, and participated in the Injury surveillance and in-depth suicide surveillance for 10 years, from January 2008 to December 2017. The study subjects were adult patients 18 years or older who visited EDs due to suicide attempts. The main explanatory variable is whether psychiatric treatment was provided in previous suicide attempts. The main outcome variable was sui- cide related mortality.

Results: The study included 2144 suicide attempt patients with a previous history of suicide attempts. Among these, 1335 patients (62.2%) had received psychiatric treatment in previous suicide attempts. Mortality was sig- nificantly different between the psychiatric consultation group (n = 33, 2.5%) and non-consultation group (n = 47, 5.8%) (P b 0.01). In multivariate logistic regression analysis, previous psychiatric consultation showed a sig- nificant association with low mortality (adjusted OR 0.41; 95% CI [0.23-0.72]) and selecting non-fatal suicide methods (adjusted OR 0.47; 95% CI [0.36-0.61]).

Conclusion: Patients who received psychiatric consultation in previous suicide attempts had a lower suicide- related mortality in current ED visits as compared to patients who did not, and this may have been related to choosing non-fatal suicide methods.

(C) 2020

Introduction

Suicide is a significant cause of death and Public health problem in the world [1,2]. The health burden of suicide should be considered im- portant regardless of region and age group [3]. Suicide attempt is the most crucial clinical predictor of eventual suicide, and some studies have estimated that suicide risk among those who have attempted sui- cide is almost 100 times higher than the general population [4-9]. follow-up care after suicide attempts has been considered as an essen- tial method for suicide prevention, although there is no evidence that specific preventive interventions outperform other methods [10,11].

* Corresponding author at: Seoul National University Bundang Hospital, 82 Gumi-173 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do 13620, South Korea.

E-mail address: [email protected] (J. Jeong).

Emergency Departments (EDs) are vital locations for screening indi- viduals at high risk of suicide and for providing psychiatric services to those who have attempted suicide [12,13]. Although there is a wide var- iation depending on the data selected as a sample, it is known that about 1000 attempted suicide or self-harm patients visit the EDs in the US every day [14]. Notably, the effect of several intervention methods on suicide attempt patients who visited EDs has been reported [15-19].

Previous suicide prevention studies conducted in EDs defined the primary outcome variable as subsequent suicide attempts or Suicidal behaviors. These studies reported that suicide-related behaviors de- creased after the intervention, but some subsequent suicide attempts were inevitable even after the intervention [20-22]. There is little re- search on how psychiatric interviews in the ED for suicide attempts af- fect repeated suicide attempts. This study aims to examine the hypothesis that people who received emergency psychiatric consulta- tions in previous suicide attempts would have lower mortality rates

https://doi.org/10.1016/j.ajem.2020.05.030

0735-6757/(C) 2020

than those who did not receive services when they visited the EDs for subsequent suicide attempts.

Method

Study design

The study was a retrospective, Multicenter observational study to examine the effect of previous emergency psychiatric consultation on current subsequent suicide attempts. The institutional review board of the Seoul National University Hospital reviewed and approved the study; informed consent was waived after review of the protocol (IRB No.: 1803-023-926). The research program funded by the Korea Cen- ters for Disease Control and Prevention (KCDC) supported this work.

Study setting and population

KCDC has been conducting an ED-based injury in-depth surveillance (EDIIS) since 2006. This surveillance system aims to produce in-depth data on injury mechanisms and risk factors of injured patients who visit EDs. Subsequently, primary data from these sources are used to prevent injury. The EDIIS started in five hospitals in 2006, and gradually expanded the number of participating hospitals. Since 2015, 23 hospi- tals have been collecting data. All participating hospitals are divided into four groups to investigate in-depth injury data further. The four groups were (1) transportation accidents, (2) head and Spinal injury,

(3) preschool child injury, (4) suicide, poisoning, and fall-down. We used suicide-related in-depth variables collected from the fourth group, records of which were maintained at six hospitals. This study in- cluded suicide attempt patients with a history of previous suicide at- tempts, among patients who were 18 years of age and older who visited six in-depth research hospitals from 2008 to 2017. Each of the six hospitals had a different year when they started participating in the survey. Three hospitals collected data from 2008 to 2017 and the other three hospitals from 2010 to 2017. Cases of suicide attempts were defined as any patient who tried to harm himself/herself, includ- ing death on arrival. The cases with no clinical outcomes or no informa- tion about the suicide method were excluded from this study.

Data collection

The participating hospitals collect 58 standard variables for all in- jured patients in the ED. These standard variables collected are based on the core data set of the International Classification of External Causes of Injuries (ICECI) proposed by the World Health Organization, includ- ing demographics, prehospital emergency medical services records, clinical findings, medical treatment in the ED, ED disposition, and pa- tient outcomes [23]. The intention of injury, risk factors for suicide, and history of suicide attempts were included in standard variables. Fur- ther, in-depth injury surveillances were conducted as to how suicide at- tempts were made and whether patients had received emergency psychiatric consultations after past suicide attempts.

Each hospital has a dedicated data collection coordinator to collect data on injured patients who visit EDs. Prehospital and hospital data were collected from emergency medical services (EMS) run sheets, and medical and nursing records. After registering the monthly data in the participating hospitals, missing values were checked and reconciled through QA meetings to identify reclassifications and verify the validity of the data. The QA team analyzed the data and errors to provide feed- back to each participating hospital so the undetermined and missing values could be corrected.

Data variables

Exposure variable

The primary exposure of this study was whether the patients had re- ceived emergency psychiatric consultation during a previous suicide at- tempt. Data were collected through interviews either with the patient or the caregiver.

Outcome variable

The primary outcome of this study was in-hospital mortality, includ- ing death on arrival. Additionally, the choosing of fatal suicide methods was investigated as secondary outcomes. Two criteria defined lethal sui- cide methods, the Columbia-Suicide Severity Rating Scale (C-SSRS) and case fatality Ratio (CFR) [24-27]. Originally, the C-SSRS classifies the le- thality of actual suicide attempts into six levels (0: no physical damage, 1: minor physical damage, 2: physical damage, which needs medical at- tention, 3: moderately severe physical damage, 4: severe physical dam- age, 5: death). In case of mild injuries that can be discharged from EDs (C-SSRS 0 or 1 or 2), it was not very easy to distinguish clearly the differ- ence in this study. Therefore, we classified the severity of suicide at- tempts into four levels: discharge from the ED (score 2), hospitalization in the general ward (score 3), admission in the intensive care unit (score 4), and death (score 5). Then the mean of each methods’ C-SSRS was calculated. We also calculated the CFR of each suicide method. Methods with lethality below 5% were considered non-fatal. Although C-SSRS and CFR tended to be proportional to each other, CFR was applied to the final analysis because of necessary modifications to the C-SSRS.

Confounder variable

Gender, age, alcohol consumption at the time of injury, insurance status, season, injury time, and hospital were considered as confounder variables for the primary outcome. Suicide is attributed to many factors, such as social, psychological, and geophysical [28]. acute alcohol use is associated with suicide, and alcohol dependence is a significant risk fac- tor for suicide [29]. In this study, the state of alcohol consumption was recorded through the patient or guardian’s statement. The seasonality of suicide has been noted in several researches [30].

Statistical analysis

The chi-square test was used to identify the significance of the differ- ences between participants who did or did not receive emergency psy- chiatric consultation after previous suicide attempts. Multivariate logistic regression analysis was used to obtain an adjusted odds ratio (OR) and 95% confidence interval (95% CI) between psychiatric consul- tation history of previous suicide attempts and mortality. Statistical analysis was performed using SAS 9.4 (SAS Institute Inc., NC, USA).

Results

Data of 828,509 injured patients were collected from six deep sur- veillance hospitals during the study period. A total of 18,635 patients visited the EDs due to suicide attempts, of whom 2408 had previous sui- cide attempts. One hundred and six patients without ED results or sui- cide information were excluded. Data from 2144 patients were analyzed (Fig. 1).

Table 1 shows the characteristics and differences between the two groups for each of the confounding factors. There was a significant dif- ference in age, gender, alcohol, season, method, and mortality. Table 2 compares the lethality of each suicide method. Case Fatality Ratio (CFR) and the Columbia-Suicide Severity Rating Scale (C-SSRS) were used to calculate fatality. Hanging was a fatal suicide method, which showed a 28% fatality rate. On the other hand, no deaths were registered for patients who had attempted self-cutting. The CFR and C-SSRS showed relatively similar trends.

Fig. 1. Recruitment flowchart.

Table 3 shows the mortality rates and the number of lethal suicides for consultation and non-consultation groups. Mortality rates were sig- nificantly lower in the consultation group than in the non-consultation group. The proportion of those who chose lethal suicide was also signif- icantly lower in the consultation group than in the non-consultation group.

Discussion

This multicenter observational study revealed that patients who had psychiatric consultation at a previous suicide attempt tend to select less

Table 2

Lethality of each suicide methods

		Total			Alive			Dead			CFR	C-SSRS
		N	(%)		N	(%)		N	(%)		(%)
Method	Hanging	130	6.1		94	4.6		36	45.0		27.7	3.2
	Fall down	45	2.1		33	1.6		12	15.0		26.7	3.8
	Drowning	28	1.3		22	1.1		6	7.5		21.4	2.9
	Pesticide	179	8.3		163	7.9		16	20.0		8.9	3.2
	Gas	177	8.3		173	8.4		4	5.0		2.3	3.0
	Poison	100	4.7		99	4.8		1	1.3		1.0	2.6
	Drugs	1114	52.0		1109	53.7		5	6.3		0.4	2.6
	Cut	364	17.0		364	17.6		0	0.0		0.0	2.3
	Others	7	0.3		7	0.3		0	0.0		0.0	2.6
	Total	2144	100		2064	100		80	100		3.7	2.7

*CFR: Case Fatality Ratio (n of Dead/n of Total).

*C-SSRS: Columbia-Suicide Severity Rating Scale.

lethal suicide methods and survive at a current suicide attempt. To the best of our knowledge, this is the first study to investigate the relation- ship between previous psychiatric consultations and clinical outcomes in the ED in current suicide attempts.

One study carried out in one ED tried to find the effects of psychiatric consultation for the Self-poisoning patients who attempted suicide [31]. The study only included patients who visited ED due to self-poisoning. They showed that (1) if the primary motive for the suicide attempt was a wish to die, (2) if the attempt was not impulsive, and (3) if the pa- tient was male, the psychiatric consultation positively affected the out- comes. Our study included all methods of suicide attempts, compared with this previous study.

In another study, Vaiva et al. found that contacting people by tele- phone one month after attempted suicide by self-poisoning helped

Table 1

Baseline characteristics for the study population according to consultation

	Total			Consultation			Non-consultation	P-value
	N	(%)		N	(%)		N (%)
Total	2144	100		1335	100		809 100
Age 18-29	703	32.8		478	35.8		225 27.8	b0.01
30-39	542	25.3		333	24.9		209 25.8
40-49	445	20.8		267	20.0		178 22.0
50-59	233	10.9		136	10.2		97 12.0
60-69	117	5.5		69	5.2		48 5.9
70~	104	4.9		52	3.9		52 6.4
Gender Male	687	32.0		393	29.4		294 36.3	b0.01
Female	1457	68.0		942	70.6		515 63.7
Insurance National	1656	77.2		1030	77.2		626 77.4	0.41
Medicare	366	17.1		225	16.9		141 17.4
Other	15	0.7		11	0.8		4 0.5
Unknown	107	5.0		69	5.2		38 4.7
aAlcohol Alcohol	896	50.6		495	47.9		401 54.3	b0.01
Non-alcohol	876	49.4		539	52.1		337 45.7
bSeason Spring	539	25.1		309	23.1		230 28.4	b0.01
Summer	574	26.8		388	29.1		186 23.0
Autumn	594	27.7		351	26.3		243 30.0
Winter	437	20.4		287	21.5		150 18.5
bTime 7A-3P	541	25.2		349	26.1		192 23.7	0.44
3P-11P	816	38.1		505	37.8		311 38.4
11P-7A	787	36.7		481	36.0		306 37.8
Method Hanging	130	6.1		71	5.3		59 7.3	b0.01
Fall down	45	2.1		28	2.1		17 2.1
Drowning	28	1.3		15	1.1		13 1.6
Pesticide	179	8.3		60	4.5		119 14.7
Gas	177	8.3		68	5.1		109 13.5
Poison	100	4.7		66	4.9		34 4.2
Drugs	1114	52.0		801	60.0		313 38.7
Cut	364	17.0		224	16.8		140 17.3
Others	7	0.3		2	0.1		5 0.6
Mortality	80	3.7		33	2.5		47 5.8	b0.01
a Missing data 372.

^b ED visit time.

Table 3

Difference in outcomes and lethality of methods based on previous psychiatric consultation

Factor	Mortality	Adjusted OR (95% CI)	P-value	Method lethality	Adjusted OR (95% CI)	P-value
Consultation	n/N (%) 33/1335 (3)	OR (95% CI) a0.41(0.23-0.72)	b0.01	n/N (%) 174/1335 (13)	OR (95% CI) b0.47(0.36-0.61)	b0.01
Non-consultation	47/809 (6)	1		208/809 (26)	1

^a Adjusted by potential confounders including gender, age, alcohol consumption, insurance, season, injury time at current suicide attempt, and hospital.

^b Adjusted by potential confounders including gender, age, alcohol consumption, insurance, season, injury time at current suicide attempt.

reduce the number of reattempted suicides [32]. Talking about suicide with someone itself may help prevent a suicide attempt, and it showed the importance of the detection of people at high risk of suicide at- tempts. In the same context, psychiatric consultation in the ED may play an essential role in preventing suicide and encouraging people to not commit further suicide attempts, as shown in our study.

Previous suicide prevention studies conducted in the ED used re- peated suicide attempts and suicide death as the main outcome vari- ables [34]. Our study suggested choosing fatal suicide methods as the main outcome variable in addition to suicide mortality. Studies where the suicide method was the main exposure analyzed the case fatality rate epidemiologically [35,36]. Case fatality rates in our study are similar to the previous research. There is limited information on preventing fu- ture suicide attempts or on the lethality of future attempts. We think there are advantages to our study in this regard.

Recently, EDs are being recognized as an important and promising setting for screening and intervening for suicidal behavior [12]. Brief ED interventions such as patient education, joint planning, rapid refer- ral, lethal means counseling, and caring contacts are recommended for suicidal patients in the ED [37]. Some systemic review and meta- analysis have reported that active contact and follow up interventions are effective in preventing repeated suicidal attempts [33,38]. It is note- worthy that suicide reattempts are usually considered an outcome var- iable for Intervention studies on suicide attempts in EDs. Because of the low number of suicides that result from suicide attempts during the follow-up period, it is not easy to study suicide deaths as outcome var- iables. Even after active intervention, it is difficult to prevent suicide reattempts completely, and a significant proportion of patients eventu- ally reattempt suicides. This study has the strengths of helping to under- stand the clinical characteristics and final death when revisiting to the ED with suicide reattempts.

As long as suicide is regarded as an increasing public health problem

that places a considerable burden on society, it is best to prevent suicide before it happens. For now, there is no clear way to eliminate all suicide attempts. However, an effort is still needed to reduce them. Many re- search studies have been conducted to determine how to reduce risk factors and suicide rates [20,39]. Psychiatric consultation is known to be an effective way to reduce the suicide reattempt rate, and our study adds evidence to show the possibility of reducing the severity of subsequent suicide attempts.

There appears to be seasonal variation in suicides, independent of geographic location [30,40,41]. low income and low education levels were also associated with significantly higher rates for suicide attempts in previous studies [42]. We regarded these factors as confounders.

Although this study showed psychiatric consultation after previous suicide attempts lowered the lethality of a subsequent suicide attempt, a way to not only lower the fatality but also prevent the suicide attempt itself still needs to be found. Further study and effort will be required to ensure the effectiveness of the psychiatric consultation program in the ED on reducing suicide attempts.

This study has some limitations. First, because this was a retrospec- tive observational study, there may be biases that are not controlled. It is hard to do experimental or randomized controlled research on the sub- ject of suicide and to collect a sufficient number of participants during a certain study period. Second, the population of this study is limited to six university hospitals in Korea, located in large cities, which may

limit the generalization of current research results. It also included a ‘death on arrival (DOA)’ patient, which may have made it difficult to ob- tain accurate information about the patient. Third, acute alcohol use that we used for our analysis as a confounding factor has the limitation of being reported, not objectively measured. EDs of South Korea do not routinely measure blood alcohol concentration and may be considered illegal without informed consent [29,43]. We measured the lethality of method using C-SSRS and CFR. In this study, since the items related to C-SSRS were not examined separately, the actual lethality and medical damage items of C-SSRS were estimated based on the obtained data. In the course of the conversion, there may be a difference between the original scale and the new manipulated one. The CFR was also produced only in patients finally analyzed in this study and may not represent the entire country. Later, national CFR calculation studies using more exten- sive injury surveillance data will need to be conducted.

Finally, based on the results of this study, it is necessary to follow up with further studies on how various intervention programs for suicide attempts affect the choice of suicide methods and the injuries caused by suicide attempts.

Conclusions

In conclusion, patients who received emergency psychiatric consul- tation after previous suicide attempts had significantly lower suicide mortality rates at current ED visits than those who did not, which is most likely related to the selection of a nonfatal suicide method.

Funding acknowledgement

This study was supported and funded by the Korea Centers for Dis- ease Control and Prevention (KCDC).

CRediT authorship contribution statement

Jeong Min Son:Conceptualization, Methodology, Writing – original draft.Joo Jeong:Conceptualization, Methodology, Funding acquisition, Formal analysis, Data curation, Writing – review & editing, Supervi- sion.Young Sun Ro:Conceptualization, Methodology, Funding acquisi- tion, Formal analysis, Data curation, Writing – review & editing, Resources.Wonpyo Hong:Resources.Ki Jeong Hong:Writing – review & editing.Kyoung-Jun Song:Supervision.Sang Do Shin:Supervision.

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