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Environ Health Prev Med. 2016 May; 21(3): 164–172.
Published online 2016 February 16. doi:  10.1007/s12199-016-0511-9
PMCID: PMC4823220

Relationships between suicidal ideation and psychosocial factors among residents living in Nagano Prefecture of Japan

Abstract

Objectives

Feeling ashamed for seeking help when distressed is known to be a critical factor promoting suicidal behaviors. The objective of this study was to examine the relationship between suicidal ideation and psychosocial factors, including worries or anxieties, having a person to confide in, feeling ashamed for seeking help when distressed, and K6 score.

Methods

Fourteen out of 77 municipalities from Nagano Prefecture participated in this questionnaire survey. Participants of both sexes over 20 years of age were randomly selected according to age distribution in each municipality. Association between suicidal ideation and sociodemographic and psychosocial factors, including “feeling ashamed for seeking help”, were determined by multiple logistic regression analysis.

Results

Among a total of 11,100 participants, 7394 (66.6 %) returned the questionnaire. 2147 participants responded properly to essential study parameters and were submitted to the final analyses. The adjusted odds ratio of suicidal ideation was 2.09 (95 % CI 1.49–2.94) among participants feeling ashamed for seeking help, compared to those not feeling ashamed. Although the rate of “no person to confide in” was 4.4 %, participants who responded with “no person to confide in” had significantly increased odds ratio of suicidal ideation compared with those who responded with “having a person to confide in” (OR 1.97, 95 % CI 1.12–3.47).

Conclusions

Our findings suggest a need for tailored intervention targeting individuals at risk by gatekeepers to encourage individuals at risk to overcome feeling ashamed for seeking help and to cultivate an appropriate person to confide in.

Keywords: Suicide, Suicidal ideation, K6 score, Gatekeeper, Feeling ashamed

Introduction

An estimated 804,000 deaths by suicide occurred worldwide in 2012, representing an annual global age-standardized suicide rate of 11.4 per 100,000 (15.0 for males, and 8.0 for females) [1]. Japan has been ranked as having the fifth highest suicide rate in the world [1]. In Japan, the annual number of suicide deaths exceeded 30,000 during the period from 1998 to 2011, and then slowly declined to 27,000. The crude suicide rate was 21.4 per 100,000 in 2013 [2]. In Nagano Prefecture where we conducted this survey, suicide deaths have numbered 500 per year in recent years, representing a crude suicide rate of 20.1 per 100,000 [3]. The World Health Organization (WHO) has adopted a plan for suicide prevention as an integral part of its mental health plan, with the goal of reducing the suicide rate in countries by 10 % by 2020 [1].

Suicidal behaviors are thought to develop from worries or anxieties and depression [46]. Suicidal ideation is a risk factor associated with attempted or completed suicide [7]. A key element of suicide prevention is to alleviate suicidal ideation by effective intervention of gatekeepers [1]. Prefectural and local governments in Japan have taken administrative suicide prevention initiatives such as adoption of gatekeepers trained [8, 9] for countermeasures against suicide. The attitude of individuals at risk of suicide toward seeking help when distressed is influenced by cultural background, traditional beliefs and social connectedness [1, 10]. Feeling ashamed and discrimination associated with mental illness [1, 11] may constitute a barrier to accessing the social healthcare system’s suicide prevention program. There are cultural differences in the role of shame involved in suicide between western countries and Japan [10, 12]. Kageyama [12] reported a close association between feeling ashamed for seeking help and living in rural areas and areas with high suicide mortality rates. A sense of isolation was reported to lead to an increase in risk for suicide behavior [1]. The individual’s closest social circle––partners, family members, and friends––acts as a protective factor against the risk of suicide and has the most influence in times of crisis [1]. Kido et al. [13] reported that being currently married was significantly associated with higher expectations for mental health service, because those currently married may obtain information and knowledge about mental health service from their spouse. “Having a person to confide in” is an important protective factor for reducing the suicide risk.

To the best of our knowledge, no report has been published on the relationship between suicidal ideation and risk factors, including feeling ashamed for seeking help when distressed and having no person to confide in. Therefore, the present study was undertaken to examine the relation between suicidal ideation and several sociodemographic and psychosocial risk factors, with an emphasis on feeling ashamed for seeking help when distressed and appropriate persons to confide in.

Materials and methods

This anonymous questionnaire survey was originally designed to develop preventive measures against suicide among residents in Nagano prefecture by the Nagano Prefectural Government. The prefectural government asked all 77 municipalities to participate in the survey, and 14 municipalities (18.2 %) were willing to participate. The size of population was 44,000 residents for one city, 30,000–40,000 for 3 cities, 20,000–30,000 for one town, 10,000–20,000 for 3 towns, 5000–10,000 for one town and 2 villages, and 4000 for 3 villages. They were mostly towns and villages and thus classified as rural areas. The present survey was conducted during July through September 2010, and participants of both sexes over 20 years of age were randomly selected from 14 municipalities depending on the age distribution in each participating municipality. In principle, the officials in charge of the present questionnaire survey sent the questionnaire to subject candidates by mail, together with a briefing paper, informing them of the objective and methods of the survey, publication of the results after the survey, option to refuse participating and informed consent. The participants sent the questionnaire back by mail to the officials in an enclosed envelope. We recognized that the participants gave us the informed consent by returning the questionnaire. Questionnaire items in the survey included sociodemographic factors such as sex, age, occupational status and municipality, as well as psychosocial factors including worries/anxieties, depressive symptoms, having a person to confide in, feeling ashamed for seeking help when distressed, and suicidal ideation. Occupational status was classified into seven categories as shown in Table 1. Worries or anxieties were assessed by a question: did you have worries or anxieties during the past 30 days? Having a person to confide in was assessed by a question: do you have a person whom you confide in when distressed? Feeling ashamed for seeking help was assessed by a question: do you feel ashamed for seeking help when distressed? We classified these chosen responses into three different groups: “strongly agree and agree a little” termed as “Agree”, “strongly disagree and disagree a little” termed as “Disagree” and “neither agree nor disagree” termed as “NAD”. Depressive symptoms were evaluated with the Japanese version of Kessler’s K6 scale [14]. The K6 questionnaire is a six-item self-report that asks how frequently respondents experienced symptoms of psychological distress during the past 30 days. The participants were classified into two groups: those with and without depressive symptoms (a total K6 score of 5 or above, and 4 or below, respectively) according to the recommended cutoff point [4, 14, 15]. Suicidal ideation was assessed with the question: have you considered suicide during the past year? We assumed that some respondents might feel uncomfortable responding to the question about suicidal ideation, so that we added the following sentence in our questionnaire: If you feel uncomfortable, you do not need to answer this question.

Table 1
Sociodemographic characteristics and psychosocial factors among 2147 participants who completed all questionnaire items

We used the Chi-square test and residual analysis to compare proportions across groups and the t test for comparing averages across groups. Multiple logistic regression analysis was carried out to evaluate the odds ratio with a 95 % confidence interval for the associations between suicidal ideation and sociodemographic and psychosocial factors, including sex, age, occupational status, municipality, worries or anxieties, having a person to confide in, and feeling ashamed for seeking help when distressed, and K6 score. All analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 21.0 by IBM (SPSS Inc., Chicago, IL, USA).

We obtained informed consent directly from the participants by returning the questionnaire. The municipal health officials were given the authorization to conduct the survey from the head of each municipality. Only the participants who returned the questionnaire were enrolled in the present survey. The basic document relating to oral informed consent from the participants on the basis of the briefing paper was recorded and preserved by the health officials under the auspice of the Committee for Preventive Measures against Suicide organized in the Nagano Prefectural Government. The protocol of the survey including the procedure to obtain the informed consent was approved and implemented by the Committee. This study and protocol including the procedure to obtain the informed consent from the participants were also approved by the Ethics Review Committee of Shinshu University School of Medicine.

Results

Among a total of 11,100 participants, 7394 (66.6 %) returned the questionnaire. 2147 participants responding properly to essential study parameters were submitted to the final analyses. The return rate in the municipalities ranged from 56.6 to 81.1 %. Male and female collection rates were 61.1 and 69.6 %, respectively. Among age groups, the highest return rate was 77.3 % for participants in their 60s, and the lowest was 50.2 % for those in their 20s, indicating that the response rate increased with age. Among the groups classified by sex and age, the highest collection rate was 80.5 % in 60–69 year old females, while the lowest was 44.2 % in 20–29 year old males.

A total of 6999 participants (94.7 % = 6999/7394) responding properly to items regarding sex, age and occupational status consisted of 3133 males (44.8 % = 3133/6999) and 3866 females (55.2 % = 3866/6999). Overall, 4352 participants (62.2 % = 4352/6999) who reported that they had worries or anxieties consisted of 1791 males (57.2 % = 1791/3133) and 2561 females (66.2 % = 2561/3866). As to the question about feeling ashamed for seeking help when distressed, 1133 (16.2 % = 1133/6999) participants consisting of 624 males (19.9 % = 624/3133) and 509 females (13.2 % = 509/3866) responded with “Agree”. The mean total K6 score was 3.6 with a standard deviation of 4.2, and 2135 participants (30.5 % = 2135/6999) were categorized as having “depressive symptoms”. Two hundred eighty-eight participants (4.1 % = 288/6999) consisting of 122 males (3.9 % = 122/3133) and 166 females (4.3 % = 166/3866) responded with “Yes” to the question about suicidal ideation during the past year.

As shown in Table 1, 2147 participants (30.7 % = 2147/6999) fully completed all the questionnaire items including the question about suicidal ideation. A total of 1461 participants (68.0 % = 1461/2147) consisting of 514 males (62.2 % = 514/826) and 947 females (71.7 % = 947/1321) reported that they had worries or anxieties.

A total of 2053 participants (95.6 % = 2053/2147) consisting of 767 males (92.9 % = 767/826) and 1286 females (97.4 % = 1286/1321) reported that they had a person whom they can confide in. As to the question about feeling ashamed for seeking help, 398 participants (18.5 % = 398/2147) consisting of 189 males (22.9 % = 189/826) and 209 females (15.8 % = 209/1321) responded with “Agree”. The mean total K6 score (standard deviation, SD) was 4.5 (4.7) for total participants with 4.3 (4.8) for males and 4.6 (4.8) for females. Eight-hundred twenty-six participants (38.5 % = 826/2147) were categorized as having “depressive symptoms”, and 224 participants (10.4 % = 224/2147) responded with “Yes” to the question about suicidal ideation during the past year, which accounted for 87 males (10.5 % = 87/826) and 137 females (10.4 % = 137/1321).

No significant gender difference was found in the rate of participants responding with “Yes” or “No” to the question about suicidal ideation. In this context, the relationship of depressive symptoms with the three psychosocial factors is shown in Table 2. The rate of participants who responded with “Agree” to the question about “feeling ashamed for seeking help” was significantly higher among participants with depressive symptoms than among those without depressive symptoms (29.5 vs 13.3 %, p < 0.01). In contrast, the rate of participants with depressive symptoms was significantly lower for responding with “Yes” to the question of having a person to confide in than those without depressive symptoms.

Table 2
The relationship of depressive symptoms with psychosocial factors among 2147 participants

Table 3 shows the sociodemographic and psychosocial characteristics of the participants who considered suicide during the past year. The participants who responded to the question about suicidal ideation were categorized into two groups, i.e., those who responded with “Yes” and those who responded with “No”.

Table 3
Sociodemographic characteristics and psychosocial factors among participants who did or did not consider suicide during the past year

On the other hand, there were significant differences in occupational status, having worries or anxieties, having a person whom you can confide in, feeling ashamed for seeking help when distressed, and depressive symptoms between those who responded with “Yes” to the question of suicidal ideation and those who responded with “No”. In occupational status, the rate of full-time employees was significantly higher for the participants who responded with “Yes” for suicidal ideation than for those who responded with “No” (34.8 vs 27.2 %, p < 0.01) as a result of residual analysis.

It was interesting to note that the rate of participants who have a person to confide in was significantly lower among the participants who responded with “Yes” to the question about suicidal ideation than among those who responded with “No” to the question (88.4 vs 96.5 %, p < 0.01). The rate of participants who responded with “Yes” to the question about worries or anxieties was significantly higher among the participants who had suicidal ideation than those who did not have suicidal ideation (91.1 vs 65.4 %, p < 0.01). The rate of participants who responded with “Agree” to the question about “feeling ashamed for seeking help when distressed” was significantly higher among participants who responded with “Yes” to the question about suicidal ideation than among those who responded with “No” to this question (34.4 vs 16.7 %, p < 0.01) as a result of residual analysis.

As shown in Table 4, the results of logistic regression analysis revealed significant relationships between suicidal ideation and various risk factors. The adjusted odds ratio of suicidal ideation was 2.09 (95 % CI 1.49–2.94) among the participants feeling ashamed for seeking help, compared to those not feeling ashamed. The significantly increased crude and adjusted odds ratios of suicidal ideation among the participants responding with “NAD” to the question was noted. The adjusted odds ratio of suicidal ideation was 2.05 (95 % CI 1.10–3.81) among participants responding with “NAD” to the question, compared to those responding with “Disagree”. The adjusted odds ratio of suicidal ideation was 2.37 (95 % CI 1.41–3.97) among participants with worries or anxieties, compared to those without those. The adjusted odds ratio of suicidal ideation was 1.97 (95 % CI 1.12–3.47) among the participants not having a person to confide in, compared to those having such person.

Table 4
Relationships between suicidal ideation and sociodemographic and psychosocial factors by logistic regression analysis

There was no significant relationship between suicidal ideation and gender, occupational status or municipality (data not shown in Table 4). The adjusted odds ratios of suicidal ideation were significantly greater for younger groups in their 20s through their 50s than for the elderly group over 70 years of age. The adjusted odds ratios of suicidal ideation among those in their 20s, 30s, 40s and 50s compared to those over 70 were 3.23 (95 % CI 1.62–6.44), 2.07 (95 % CI 1.11–3.87), 2.73 (95 % CI 1.48–5.06), and 2.28 (95 % CI 1.25–4.16), respectively.

Discussion

In comparison with the results of two nationwide surveys by the Japan Cabinet Office (JCO) [16, 17], we obtained different results in our sociodemographic and psychosocial factors. First, the participants in the present survey were older than those in the two JCO surveys. Second, the rate of having no person to confide in was small in the present survey (3.3 %) compared with those in the 2008 JCO survey (6.3 %) and in the 2012 JCO survey (6.1 %). Third, prevalence of suicidal ideation (10.4 %) in the present survey seems to be high compared with those in the 2008 JCO survey (4.0 %) and in the 2012 JCO survey (5.3 %). Higher rate of participants (10.4 %) having suicidal ideation found in the present study can be contrasted with lower rate reported by Kawakami et al. [4] that 1.5 % males and 1.3 % females had suicidal ideation during the past year. On the other hand, Ono et al. [18] reported that 10 % participants had suicidal ideation during their lifetime, while the rates of participants having suicidal ideation during their lifetime were reported to be 8.3 % by Sugawara et al. [19] and 4.2 % by Kashiwa et al. [20]. The prevalence of suicidal ideation during the past year in the present survey was similar to that of suicidal ideation during their lifetime. Higher prevalence of suicidal ideation found in this study can be interpreted that the participants responded with more serious concern to this question of suicidal ideation.

The adjusted odds ratio of suicidal ideation was 3.68 (95 % CI 2.57–5.27) among the participants with depressive symptoms compared to those who responded with “No” to this question. This result is consistent with that of the relation between suicidal ideation and depression symptom [46, 11]. The logistic regression analysis revealed that odds ratios of suicidal ideation were significantly higher among all age groups except for the elderly aged 60–69 years compared to aged 70 years or older. Similarly, having worries or anxieties, having no person to confide in, and feeling ashamed for seeking help when distressed, had significantly higher odds ratios compared to the counterparts. The present result is consistent with Ono et al. [18] reporting a significant association of life-time suicidal ideation with being younger age. The significant association of suicidal ideation with these risk factors found in the present study can be interpreted that having worries or anxieties, no person to confide in and feeling ashamed for seeking help as well as depressive symptoms might constitute the barriers to accessing the suicide prevention program. Since people feeling ashamed for seeking help might be reluctant to ask to help, gatekeepers are encouraged to examine “worries or anxieties”, “no person to confide in” and depression for individuals at risk, and to introduce these psychosocial factors to the suicide prevention program. We should create a supportive environment [8] for people of younger age to access the suicide prevention program, for example, awareness of receiving social support, willingness to receive assistance and so on. [1].

A key element in the suicide prevention program is an effective intervention by a gatekeeper, as suggested by the WHO [1] and the Japan Cabinet Office [2]. Ono et al. [21] demonstrated the effectiveness of the community-based intervention for suicide in the rural area. The intervention programs focused on building social support networks within the general public and in health-related resources, intending to reinforce human relationships and connectedness in the community, for example Gatekeeper training. The positive intervention effect was observed in the rural area, and was not observed in the populated area. It was interesting to note that the rate of participants having no person to confide in, who responded with “Yes” to the question about suicidal ideation was 1.97-fold higher than those having a person whom you can confide in, who responded with “No” to this question. This result can be taken to indicate an important role of “having a person to confide in”, which might be an eligible surrogate for a gatekeeper, and thus support a pivotal role of the gatekeeper as an expert and his/her training for the suicide prevention program [9].

Furthermore, significant association of suicidal ideation with feeling ashamed for seeking help when distressed is consistent with the findings by Kageyama [12] who reported with the residents living in rural areas of Oita Prefecture that 18.7 % of total respondents felt ashamed for seeking help when distressed, and also that feeling ashamed was associated with living in rural areas or areas with high suicide mortality rates. It is thus suggested on the basis of Kageyama’s findings that feeling ashamed for seeking help when distressed is related to the resistance to accessing health care, as suggested by the WHO [1] and Thompson et al. [11].

On the other hand, feeling reluctance in seeking help seems to be contextually comparable to feeling ashamed. It is interesting to note that when the related questionnaire item was changed from “feeling ashamed for seeking help” in the 2008 JCO survey [16] to “feeling reluctance in seeking help” in the 2011 JCO survey [17], the participants responding with “Yes” to the related question were found to increase markedly from 15.6 to 43.4 %. Since feeling reluctance in seeking help is reported to be a barrier to accessing the suicide prevention program [1, 11, 12], active intervention not only to participants feeling ashamed but also those feeling reluctance in seeking help when distressed should be implemented. There are large number of individuals at risk of suicide, who feel reluctance in seeking help, as compared with those who feel ashamed for seeking help. Therefore, gatekeepers are encouraged to prevent young individuals from performing suicidal behaviors through effective intervention to relieve feeling ashamed and reluctance in seeking help in the suicide prevention program. In light of the present findings of significant associations between suicidal ideation and some sociodemographic risk factors, gatekeepers are asked to implement effective intervention to individuals at risk of suicide in a tailor-made manner, thinking of some risk factors such as feeling ashamed or reluctance in seeking help, having worries or anxieties, depressive symptoms and young individuals. There are two strengths in the present study. First, a large number of participants were recruited for this study. The participants and their municipalities took a cooperative attitude toward the survey, as reflected by the enough rate of response (66.6 %). Thus, it is reasonable to consider that these data represent the present status relating to the suicide problem in Nagano Prefecture.

There are also some limitations to this study. First, selection of the 14 municipalities was based not on the random sampling but on their willingness to participate in the survey. The present results might have been biased by such serious concern of the municipal heads about suicide problems. Second, since this epidemiological study is cross-sectional, determining causality in the relationship between suicidal ideation and sociodemographic risk factors was beyond the purpose of the study. Third, the response rate in different municipalities might have introduced a bias with regard to the result; that is, response rate varied ranging from a minimum of 56.6 % to a maximum of 81.1 %. In addition, collection rates tended to be higher for females and those aged 60–69 compared to males and younger people. The fourth limitation involves the results analyzed for the 2147 participants who fully completed all the questionnaire items used in the study. Notably, the rates of participants responding unfavorably to the questions about having worries or anxieties, depression, a person to confide in, feeling ashamed for seeking help, and suicidal ideation were higher in this group of 2147 participants than in the participants as a whole. In particular, the rate of participants having suicidal ideation was found to increase markedly from 4.1 % in the participants as a whole to 10.4 % in the 2147 participants. So our findings seem to reflect the situations in the participants who had serious concerns about suicide.

The present study revealed that suicidal ideation is significantly associated with feeling ashamed for seeking help, having no person to confide in, having worries or anxieties, and being age-related. Our findings suggest a need for tailored (individual and age-specific) interventions by well-trained gatekeepers to encourage individuals at risk of suicide not to feel ashamed or reluctant to seek help when distressed, and to cultivate an appropriate person to confide in.

Acknowledgments

The authors are deeply indebted to health officials in the municipalities of Nagano Prefecture for their willing cooperation with the present survey. We are extremely grateful to Professor Akinori Nakata of University of Occupational and Environmental Health, Japan for reviewing this manuscript and providing useful comments.

Compliance with ethical standards

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

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Articles from Environmental Health and Preventive Medicine are provided here courtesy of The Japanese Society for Hygiene