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Impact of employment status and work-related factors on risk of completed suicide
Psychiatry Research 190 (2011) 265–270
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Psychiatry Research j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / p s yc h r e s
Impact of employment status and work-related factors on risk of completed suicide A case–control psychological autopsy study Barbara Schneider a,⁎, Kristin Grebner a, Axel Schnabel b, Harald Hampel a, Klaus Georgi a, Andreas Seidler c a b c
Department of Psychiatry, Psychosomatic Medicine, and Psychotherapy, Goethe-University, Frankfurt/Main, Germany Centre of Legal Medicine, Goethe-University of Frankfurt/Main, Germany Institute of Occupational and Social Medicine, Technical University of Dresden, Germany
a r t i c l e
i n f o
Article history: Received 8 February 2011 Received in revised form 19 July 2011 Accepted 26 July 2011 Keywords: Case–control study Psychological autopsy Unemployment Working conditions Completed suicide Outside occupation
a b s t r a c t The objective of this study was to determine the impact of work-related factors on risk for completed suicide. Psychiatric disorders and socio-demographic factors including work-related factors were assessed by a semistructured interview using the psychological autopsy method in 163 completed suicide cases and by personal interview in 396 living population-based control persons. Unemployment (in particular, for more than six months), (early) retirement, or homemaker status were associated with highly significantly increased suicide risk, independently of categorized psychiatric diagnosis. In addition, adverse psychosocial working conditions, such as monotonous work, increased responsibility and pronounced mental strain due to contact with work clients, significantly increased suicide risk as well, again independently of categorized psychiatric diagnosis. These findings demonstrate that negative consequences of unemployment, homemaker status with no outside occupation, or (early) retirement, as well as adverse psychosocial working conditions, present relevant risk factors contributing to suicidal behavior, independently of diagnosed psychiatric disorders. Employment and a positive modification of working conditions, may possibly be preventive to important adverse mental health outcomes, including suicidality. © 2011 Elsevier Ireland Ltd. All rights reserved.
1. Introduction A comprehensive number of epidemiologic studies demonstrated that suicide risk is not only impacted by categorized diagnostic psychiatric disorders and aggressive-impulsive behavior, but also by various social cofactors, such as adverse marital status and employment status (Yoshimasu et al., 2008). Furthermore, socio-economic events, such as economic crisis, are known to produce important fluctuations in suicide mortality with variations between countries with different economic and social conditions; this has recently been shown for Asian countries (Chang et al., 2009). Today, during times of economic dysbalance, uncertainty, and crisis, the relation between unemployment and risk of suicide as well as work-related factors and suicide is getting more significant, receiving increasing media attention, particularly regarding employee suicides. In controlled psychological autopsy studies, unemployment was associated with suicide with an up to nine-fold increased risk (Foster et al., 1999; Cheng et al., 2000; Gururaj et al., 2004; Chen et al., 2006), even after adjustment for axis I disorders (Foster et al., 1999) and
⁎ Corresponding author at: Center of Psychiatry, Department of Psychiatry, Psychosomatics, and Psychotherapy, Goethe-University Frankfurt/Main, HeinrichHoffmann-Str. 10, D-60528 Frankfurt/Main, Germany. Tel.: + 49 69 6301 4784; fax: + 49 69 6301 5290. E-mail address: [email protected] (B. Schneider). 0165-1781/$ – see front matter © 2011 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.psychres.2011.07.037
other co-variables (Chen et al., 2006), or combining unemployment and household duties (Khan et al., 2008), being a homemaker, retired or unemployed (Phillips et al., 2002), or combining unemployment and sick leave (Almasi et al., 2009). Moreover, being unemployed or retired was identified as risk factors for suicide in individual (Johansson and Sundquist, 1997; Lewis and Sloggett, 1998; Kposowa, 2001; Blakely et al., 2003; Ahs and Westerling, 2006; Agerbo, 2007) and in register- or census-based cohort studies (Blakely et al., 2002; Qin et al., 2003; Agerbo, 2005). The link between unemployment and suicide was frequently investigated (see Schneider, 2003). However, relatively few studies have investigated the link between working conditions and work attitude and suicide: Adverse working conditions and high workrelated stress were associated with increased suicide risk in cohort studies of particular occupational groups; these studies were carried out in the US (Feskanich et al., 2002), Canada (Ostry et al., 2007), and Japan (Tsutsumi et al., 2007). Insurance and legal reports indicated that long working hours, heavy workloads, and low social support might be related to suicide in Japan (Amagasa et al., 2005). A recent Hungarian controlled psychological autopsy study revealed an association between concern over work prospects and suicide (Almasi et al., 2009). This scarcity of studies investigating the link between working conditions and suicide is surprising, as prospective analyses have found that job characteristics and work stress appear to precipitate subsequent burnout, depressive symptoms, and risk of successive
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psychiatric diagnosis (Paterniti et al., 2002; Borritz et al., 2005; Wang, 2005; Melchior et al., 2007; Wieclaw et al., 2008). In order to investigate potential conditions increasing suicide risk, additional research is required (Ohayon, 2009). In spite of the huge number of studies regarding aspects of the work–suicide relationship several salient questions remain open. Although elevated suicide risk was repeatedly found for unemployed and retired people, suicide risk for other people without work, such as homemakers, has been hardly investigated in population-based studies. Furthermore, it remains unclear which particular sources of job stress actually affect suicide risk for the individual. The objective of this study was to determine aspects of employment status and work-related factors on suicide risk and to assess how the extent of work-related factors, such as employment status and relevance of psychosocial work load, affect the risk of completed suicide. Specifically, we hypothesized that being unemployed or being retired would increase suicide risk, even independently of psychiatric diagnosis and marital status. 2. Methods 2.1. Study population All 263 suicides (mean age 50.9 [S.D. 19.6] years; 66.2% males) who died in the Frankfurt/Main area (864,253 inhabitants on December 31, 1999) in 1999 and 2000 were included in the study. All suicides were classified as certain suicides (ICD-10 X 60–X 84) by the Center of Forensic Medicine, which must examine all deaths by unnatural or uncertain causes in this region. The relatives of 163 suicides (mean age 49.8 [S.D. 19.3] years; 64.4% males; men: 48.4 [S.D. 19.4] years; women: 52.1 [S.D. 19.1]years) were interviewed using the psychological autopsy method (Isometsä, 2001) with a semistructured interview 8.5 [S.D. 6.8]months after the suicide. Key informants of the deceased were spouses (35%, n = 57), adult children (21%, n = 34), parents (18%, 20 mothers and 9 fathers) and other relatives and friends (26%, n = 43). Sixty-three percent of the interviewees lived with the deceased. Persons who had been documented as “closest relatives” in the official police report were accepted as proxy interviewees. The study sample and the study design are described in detail elsewhere (e.g. Schneider et al., 2009). In addition, out of the 685 population-based controls contacted, 396 persons (mean age 51.6 [S.D. 17.0] years; 55.8% males, response rate 57.8%, matched to the suicides by residential area, age, and gender, frequency matching) were personally interviewed. The controls were chosen by ‘random digit dialing’. Control persons were also asked to give their permission for repetition of the interview, for interviews by two interviewers, and for asking a close relative or friend to give an interview about the control person himself or herself. 2.2. Instruments and diagnostic procedure A semi-structured interview, a modified and translated version of the interview applied in the National Suicide Prevention Project in Finland including differentiated questions about employment status and working conditions (Henriksson et al., 1993a, 1993b), and the Structured Clinical Interview for DSM-IV Axis I and II disorders (lifetime; SCID-I, SCID-II, German version) were carried out with control persons and with informants about the suicide cases. Dementia and other cognitive disorders were diagnosed using the DSM-IV algorithm. The set of work-related questions was based on questions suggested by Leino and Hänninen (1995), but shortened and supplemented by a question concerning psychic strain through contact with clients at work as applied by Seidler et al. (2003). For every job held, the participants had to assess psychosocial aspects of the work environment on a scale ranging from 1 (for low stress) to 6 (for high stress). The assessment of interrater reliability, test-retest reliability, and agreement between personal and informant's interview for DSM-IV axis I and axis II diagnoses, employment status, working conditions and socio-demographic features were measured using kappa statistics, Kendall's tau, and Intraclass correlation coefficients (ICC; one-way (Shrout and Fleiss, 1979)). These coefficients were found to be at least good for interrater reliability and test–retest reliability. Comparison of personal and relative's interview among control subjects generated kappa coefficients above 0.79 for most axis I and above 0.65 for most personality disorder diagnoses (Schneider et al., 2004). Kappa coefficients were excellent for most work-related variables (≥0.83) and at least moderate for the variable ‘student’ (kappa = 0.65) and for ‘anticipation of changes in the future’ and direction of anticipation (kappa = 0.66, each). Sensitivity and specificity were high for all assessed variables (≥ 80%) with exception of ‘student’ (sensitivity = 50%). For psychosocial working conditions, dimensional scores by personal and informant's interview were significantly correlated (tau ≥ 0.63). The study protocol was approved by the ethics committee of the Medical Faculty of the University of Frankfurt/Main and carried out in accordance with the ethical standards laid down in the Declaration of Helsinki. Written informed consent was obtained by all interviewees after the aims of the study and all procedures had been fully explained.
2.3. Statistical analyses The statistical analyses were performed with SPSS version 17.1. Binary logistic regression analysis was used to estimate the odds ratios (OR) and their 95% confidence intervals (95% CI) for the association between suicide and the assessed risk factors. The unconditional logistic regression analysis was adjusted for age group and gender and in further models also for axis I and axis II disorders, and living together with one's partner, respectively. With the exception of the set of work-related questions (Leino and Hänninen, 1995), all variables were introduced as categorized variables in the analyses. The variables assessing psychosocial factors at work were linearly introduced into the logistic regression models. As the association between psychosocial factors at work and suicide risk might be nonlinear, we also performed logistic regression analysis with a linear and (additionally) a squared term of the psychosocial factors. Odds ratios and confidence intervals were not calculated for variables with fewer than five subjects in suicides or in controls in one of the subgroups. Furthermore, adjusted odds ratios were not calculated for variables with fewer than two subjects in one of the subgroups for axis I disorders or personality disorders in the suicide or in the control group. The level of statistical significance was set at α = 0.05 (two-sided).
3. Results As shown in Table 1, unemployment revealed the most increased risk of suicide. Twenty-one suicides (84% of all unemployed suicides) and four control persons (80% of all unemployed controls) were unemployed for a period of more than 6 months. After adjustment for psychiatric disorders and partnership, the estimated suicide risk was about three times higher for retired people than for employed persons (OR = 3.0; 95% CI 1.1–8.2). Being temporarily employed and being self-employed did not reveal significant odds ratios (Table 1). Being ‘without work’ was associated with an about three times elevated risk (Table 1), even after adjustment for psychiatric disorders and partnership (OR = 3.2; 95% CI 1.5–7.0). A significantly increased risk was associated with disability pension (Table 1). Stratification for age groups showed very similar results for the age group 31 to 60 years as for the entire sample with even higher odds ratios for unemployment (OR = 21.8; 95% CI 3.4–140.0) and for being ‘without work’ (OR = 2.8; 95% CI 1.2–7.0; odds ratios after adjustment for axis I disorders, personality disorders and status of cohabitation). Difficulties with sick leave or retirement significantly increased suicide risk (OR = 3.5; 95%
Table 1 Association between suicide and current work circumstances, status of employment, and kind of retirement. Control persons (N = 396) Kind of employment (Self-)employed Unemployed Retired Student Full-time homemaker On sick leave Status of employment Permanently For a limited period, temporarily Self–employed Without work Kind of retirement Not retired, old age or widow's pension Disability pension Unemployment pension
Suicides (N = 163)
OR (95% CI)
219 (55.3%) 5 (1.3%) 124 (31.3% 13 (3.3%) 33 (8.3%) 2 (0.5%)
66 (40.5%) 24 (14.7%) 51 (31.3%) 11 (6.7%) 9 (5.5%) 2 (1.2%)
1 16.1 (5.9–44.1) 2.2 (1.1–4.3) 2.3 (0.9–5.9) 1.2 (0.5–2.8) –
176 (44.4%) 10 (2.6%)
51 (31.3%) 6 (3.7%)
1 2.3 (0.8–6.8)
33 (8.3%) 177 (44.7%)
9 (5.5%) 97 (59.5%)
0.9 (0.4–2.1) 3.1 (1.9–5.0)
381 (96.2%)
146 (89.6%)
11 (2.8%) 4 (1.0%)
15 (9.2%) 2 (1.2%)
1 4.0 (1.7–9.1) –
Eight persons were students and employed and included in employed, 3 persons were housewives and employed and included in employed, 1 person was unemployed, but had a temporary job and were included in employed, 5 people were on sick leave, although employed or own business and were included in employed. OR: adjusted for sex and age groups; –: not calculated because of low sample size.
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Table 2 Association between suicide and level of education and professional training. Control persons (N = 396) Level of education High (at least twelve years) Middle Low (less than ten years) Level of professional training University, university of applied sciences Apprenticeship, vocational college Semi-skilled, no professional training Not applicable (e.g. young people)
Suicides (N = 163)
OR (95% CI)
OR (95% CI)*
OR (95% CI)**
1 1.9 (1.1–3.3) 3.2 (2.0–5.1)
1 1.7 (0.8–3.6) 2.3 (1.1–4.6)
1 1.7 (0.8–3.7) 2.4 (1.2–4.8)
1 2.4 (1.4–4.2) 8.3 (4.2–16.5) 4.0 (1.2–12.6)
1 2.3 (1.1–5.1) 12.7 (4.2–38.2) 6.7 (1.4–32.6)
1 2.4 (1.1–5.4) 13.4 (4.4–41.0) 5.3 (1.0–27.8)
a
171 (43.2%) 89 (22.5%) 136 (34.3%)
41 (25.6%) 35 (21.9%) 84 (52.5%)
b
c
107 (27.1%) 242 (61.3%) 37 (9.4%) 9 (2.3%)
18 (11.0%) 90 (55.9%) 45 (28.0%) 8 (5.0%)
OR: adjusted for sex and age groups; *additionally adjusted for axis I and personality disorders; **additionally adjusted for axis I disorders, personality disorders and status of cohabitation. a 3 Cases missing. b 1 Control missing. c 2 Cases missing.
CI = 1.1–11.5), but this association lost its statistical significance after adjustment for psychiatric disorders and partnership (OR = 2.5; 95% CI = 0.6–11.3). After adjustment for different axis I disorders and personality disorders, the odds ratios remain nearly the same as the crude odds ratios and as the odds ratios adjusted for all axis I disorders. Analyses with further adjustment for other variables than mental disorders and status of cohabitation, such as treatment history, use of medical and non-medical drugs, smoking, having children, and income, were performed. Adjustment for these variables did not alter the results and therefore are not presented here. Low educational level was associated with a more than twofold increased suicide risk. Suicide risk was particularly highly elevated in persons who were only semi-skilled or had no professional training (Table 2). In working people, suicide risk was about three times higher in those with at least three jobs within the last 5 years than in those with only one job in the last 5 years (suicides: 25.6%, control persons: 9.7%, OR = 3.0; 95% CI = 1.2–7.6, after adjustment for psychiatric disorders and partnership OR = 2.6; 95% CI = 0.8–8.9). Suicide victims had more often experienced more monotonous work, higher responsibility and higher psychic strain due to contact with clients at work according to their relatives' information. The suicide risk was increased, even after adjustment for psychiatric disorders and partnership (Table 3). Being unsatisfied with colleagues and boring work were associated with increased suicide risk; these associations lost their statistical significance after adjustment for psychiatric disorders and partnership (Table 3). The analyses with the squared terms (additionally to the linear terms) revealed significantly elevated odds ratios for squared time pressure and squared satisfaction with colleagues (no table). In terms of anticipation of changes in the future, 35.6% of the control persons and 27.7% of the suicides anticipated changes. Ninety
percent (89.9%) of the controls and 27.7% of the suicides deemed the anticipated changes to be positive; anticipation of changes in the future showed significantly reduced suicide risks (OR = 0.5; 95% CI = 0.4–0.9; after adjustment for psychiatric disorders and partnership OR = 0.4; 95% CI = 0.2–0.7). In the multivariate analysis (Backstep-WALD) being unemployed, retired, a homemaker, suffering from axis I disorders, personality disorders or not cohabitating remained as significant independent risk factors in the final model with the highest odds ratios for ‘unemployed’ (Table 4). If the various groups of axis I disorders were separately included in the multivariate analysis (BackstepWALD), being unemployed always revealed significantly increased odds ratios with the lowest odds ratio (OR = 12.4; 95% CI 4.4–34.7) after having introduced substance use disorders in the model (OR = 3.0; 95% CI 1.9–4.7). 4. Discussion Our most important finding is that being without work (including all people who were not in the labor force, i.e. not in paid employment or self-employment) was strongly, more than two-fold, associated with increased suicide risk with a more than 16-fold increased risk for unemployment, an about three-fold increased risk for being retired and an about six-fold increased risk for being a homemaker. Furthermore, low levels of educational training, low levels of professional training, and frequent job fluctuations, e.g., having three or more jobs in the last 5 years, were associated with increased suicide risk. Adverse working conditions, such as high responsibility or monotonous work, slightly increased suicide risk. Adjustment for axis I disorders and personality disorders and adjustment for partnership do not substantially alter the effect of ‘not working' on completed suicide.
Table 3 Association of psychosocial factors at work and suicide (only [self-]employed). Median [quartiles]
Variety of work (1 = very varied work to 6 = very monotonous) Interestingness of work ((1 = very interesting to 6 = very boring) Satisfaction with superiors (1 = very satisfied to 6 = very dissatisfied) No superiors(= 0) included in analysis Satisfaction with colleagues (1 = very satisfied to 6 = very dissatisfied) No colleagues included in analysis Psychic strain through contact with clients (1 = very little to 6 = very much) No clients included in analysis Time pressure (1 = very little to 6 = very much) Responsibility (1 = very little to 6 = very much)
Control persons
Suicides
2 [1; 3] 2 [1; 3] 2 [2; 3] 2 [1; 3] 2 [1; 2] 2 [1; 2] 2 [1; 3] 0 [0; 3] 3 [2; 5] 2 [1; 3]
3 3 3 2 2 2 2.5 1 3 4
[2; 4.5] [1; 4.25] [1.5; 5] [1; 5] [1; 3] [1; 3] [1; 4] [1; 4] [1; 5] [1; 5]
OR (95% CI)
OR (95% CI)*
OR (95% CI) **
1.9 (1.4–2.5) 1.8 (1.3–2.3) 1.3 (1.0–1.7) 1.2 (1.0–1.6) 1.5 (1.0–2.1) 1.5 (1.0–2.0) 1.3 (0.9–1.7) 1.5 (1.2–1.9) 1.0 (0.8–1.2) 1.6 (1.2–2.0)
1.5 (1.1–2.0) 1.3 (1.0–1.8) 1.1 (0.8–1.5) 1.1 (0.9–1.4) 1.2 (0.8–1.8) 1.2 (0.8–1.8) 1.1 (0.7–1.6) 1.6 (1.2–2.1) 0.9 (0.7–1.2) 1.4 (1.1–1.8)
1.5 1.3 1.1 1.1 1.2 1.3 1.1 1.6 0.9 1.4
(1.1–2.0) (0.9–1.8) (0.8–1.5) (0.9–1.4) (0.8–1.9) (0.8–1.9) (0.7–1.6) (1.2–2.1) (0.7–1.2) (1.1–1.8)
OR: adjusted for sex and age groups; *additionally adjusted for axis I and personality disorders; ** additionally adjusted for axis I disorders, personality disorders and status of cohabitation; the ordinal values (1 to 6) for the psychosocial factors were included as continuous variables in the logistic regression model. The stated OR gives the risk elevation per 1 point increase of a single psychosocial factor.
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Table 4 Logistic regression analysis of association between work circumstances, Axis I disorders, personality disorders, cohabiting, and suicide (Backstep-WALD). OR (95 % CI) Unemployed Retired Homemaker Axis I disorder Personality disorder Not cohabitating
16.8 (3.7–77.0) 2.3 (1.1–4.5) 5.3 (1.3–21.7) 13.2 (6.1–28.9) 4.8 (2.6–8.9) 3.0 (1.6–5.6)
OR: adjusted for sex and age groups; variables included in the analysis: employment status, axis I disorders, personality disorders, and partnership.
Our study shares the general methodological strengths and weaknesses of controlled psychological autopsy studies. A major strength of this study design is that information of working conditions at the exact time of the suicide is gathered. These methodological considerations, such as retrospective information and lack of nonresponder analysis of interviewees of suicides, have been described in detail in previous articles (e.g., Schneider et al., 2009). With respect to the present topic, some particular limitations have to be addressed: (a) Our response rates were relatively low, but similar to those noted in several Western controlled psychological autopsy studies (e.g., Hawton et al., 2002). Due to data protection regulations in Germany, we could not perform non-responder analyses in our sample for estimation of selection effects. However, we have no hints for selection bias; Prevalences of psychiatric disorders and frequency of employment status correspond to those of the general population of Germany (http://www.frankfurt.de/ sixcms/media.php/678/2002_2_Mikrozensus1997_2001.pdf). (b) For some occupational factors (particularly early retirement and psychosocial workload), additional adjustment for psychiatric disorders led to decreased odds ratios in our study. This could be at least partly explained by a potential overadjustment: Overadjustment is defined as control for an intermediate variable on a causal path from exposure to outcome. As unemployment represents a potential risk factor for psychiatric disorders, and as psychiatric disorders represent risk factors for suicide, psychiatric disorders might partly constitute an intermediate factor on the causal pathway from unemployment to suicide. The causality of the associations between psychiatric disorders, unemployment, working conditions and suicide are not yet clarified (Blakely et al., 2003) and the association between unemployment and suicide in subjects with psychiatric illness is small (Agerbo, 2005). Unfortunately, we were not able to clarify the temporal sequence of unemployment and psychiatric disorders in our retrospective case–control study definitely. Therefore, additional adjustment for psychiatric disorders might have led to an underestimation of the increased suicide risk of unemployed people. Mental illness might be a step on the causal pathway from social position to suicide (Agerbo et al., 2007) and, furthermore, a mediating factor could be that treatment and aftercare perhaps focus on the larger proportion of patients who are the most disadvantaged. Regarding the temporal sequence of unemployment and psychiatric illness, our data do not provide hints that mental disorder was followed by unemployment or that unemployment was higher in individuals with more severe illness, e.g. in major depression with recurrent episodes than with a single episode. However, mental disorders might have been less severe in control persons than in suicides. This could have biased the results. (c) In our study, agreement between proxy and self-interview was high for psychiatric diagnoses (Schneider et al., 2004) and at least moderate for work-related factors among control subjects (see above). As the relatives were not aware of symptoms or would overestimate them, exposure might be misclassified. This error may also bias the results. However, this misclassification could only explain a small part of the overall strong effect. (d) Participation in the labor force is different for men and for women in the population of Frankfurt (http://www.frankfurt.de/sixcms/media.php/678/ 2005_1_%20Kurzinfo_Arbeitslosigkeit%202000-2005.pdf) and in our study population; unemployment (Kposowa, 2001; Qin et al.,
2003) and work-related factors might have different impact on male and female suicide risk. However, analyses stratified for gender showed very similar results for males and females; due to the small sample size we decided against presenting these findings. (e) As suicides are rare events and our study population was restricted to the German metropolitan Frankfurt (Main) area, the sample size of our study is relatively small. Due to the small sample size odds ratios were unstable with partly relative wide confidence intervals; thus, precise risk estimation is limited and chance could be an alternative explanation of the observed associations; therefore, completely unequivocal conclusions could not always be guaranteed. However, in spite of these possible shortcomings, the associations between unemployment, other work-related factors, and suicide remain clearly obvious. (f) As the relatives were not aware of symptoms and problems or would overestimate them, exposures might be misclassified. This error may also bias the results. However, this misclassification might only explain a small part of the effects. Consistent with general population-based psychological autopsy studies including all age groups educational underachievement (Zhang et al., 2004) and being unemployed (Foster et al., 1999; Cheng et al., 2000; Gururaj et al., 2004) were identified as predictors for suicide, even after adjustment for psychiatric disorders, which had often been seen as one of the most important links between unemployment and suicide (Chan et al., 2007). In our study, the odds ratio for unemployment was higher than in all other controlled psychological autopsy studies and independent of psychiatric disorders and partnership status. As most of the suicides were not fired or given notice within the last three months before committing suicide (Kõlves et al., 2006), recent job loss could not be the cause for this high suicide risk. In our study, most suicides and control persons were unemployed for a period of more than six months. This is similar to the data for Frankfurt (Main) (http://www.frankfurt.de/sixcms/ media.php/678/2002_2_Mikrozensus1997_2001.pdf) and Germany, where in general the majority of unemployed people are long-term unemployed persons (Karr, 2002), which is usually associated with higher suicide risk than short-term unemployment (Classen and Dunn, 2011). However, contrary to our study, long-term unemployment is defined as unemployment lasting for longer than one year in Germany. Long-term unemployment is associated with diminished financial security and status and a considerable source of social distress, family tensions, and loss of self-esteem. Furthermore, there might by other variables, which are causal to both, unemployment and suicide. Poor education and low level of professional training might be such factors; both were significantly associated with unemployment in our study (data not shown). Moreover, various other factors, such as unemployment insurance or social isolation might be involved in the pathways between unemployment and suicide and influence the association between unemployment and suicide. Furthermore, it must be mentioned that our study was carried out in the area of Frankfurt/Main and the data were collected during the years 1999 and 2000. Economy was relatively stable in this period and moreover, the area of Frankfurt/Main has a relatively stable economy and usually low unemployment rates, even in periods of mass unemployment and mass-layoffs. Therefore, unemployment in our study might be very different from unemployment in studies in periods and/or regions with mass unemployment, as suicide risk might be increased by mass unemployment and mass-layoff (Classen and Dunn, 2011). In periods of mass unemployment monetary and health policies might affect suicide. In economically stable periods and regions, in unemployed persons more individual interventions are needed in order to reduce suicide risk. Estimated suicide risk for full-time housewives/house husbands was almost fivefold increased. This high suicide risk of full-time homemakers is compatible with a potential protective effect of being employed against risk of suicide. These findings are supported by those of the SUPRE-MISS study having found that being a homemaker
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was associated with a higher risk for repeated suicide attempts (da Silva Cais et al., 2009). In agreement with the results of a controlled psychological autopsy study in people aged 60 and older (Harwood et al., 2006), being retired doubled suicide risk. Although retirement was repeatedly found as a recent life event in elderly suicides compared to younger ones (Pompili et al., 2008), suicide victims were not more frequently retired in the last three months (Kõlves et al., 2006). Thus, increased suicide risk caused by retirement as recent life event could be ruled out. As the increased suicide risk among early retired people is mainly not explained by disability pension due to psychiatric disorders, other disorders leading to disability pension should be considered as a possible explanation of the increased suicide risk of early retired people. Furthermore, several contributory factors might be related to retirement, such as social identity (Michinov et al., 2008), which could reflect underlying factors for suicide risk. Although we could not prove that adverse working conditions were causally related to suicide using the present study, in terms of working conditions, increased burden of job responsibility, much social strain through client contacts, and very repetitive monotonous work were associated with slightly increased suicide risk, independently of psychiatric condition and living with one's spouse. Despite methodological differences including other variables for assessment of working conditions, our results are supported by findings in saw mill workers (Ostry et al., 2007) and male Japanese workers (Tsutsumi et al., 2007), which reported that low psychological demand and low control at work were associated with increased suicide risk. However, the association between stress at work and suicide risk might be nonlinear (e.g. U-shaped), and additional stress at home might modify suicide risk (Weinberg and Creed, 2000; Feskanich et al., 2002). Stress at home was not included in our analyses; however, our results indicate that the relationship between psychosocial working conditions and suicide might be non-linear (super-linear) for some psychosocial work-related variables, e.g. for time pressure. Furthermore, self-rating of psychosocial working conditions might be prone to substantial recall bias, such as denial of stress as a coping mechanism. Moreover, some variables representing “classical” occupational stress models, such as included in the job demand/control model (Karasek et al., 1981) or in the effort/ reward imbalance model (Siegrist et al., 1990), were not assessed in the present study. Working conditions were only assessed in employed people. Past adverse working conditions might have led to psychic or physical impairment; however, we did not assess temporal sequences of these and other variables which might be contributing factors in the complex pathways to suicide. Although it remains open to which extent our results from a small sample size in a defined region and time period can be generalized to other cohorts or another social context, our results demonstrate that employment status, in particular unemployment and being retired, are important risk factors for suicide, independently of psychiatric disorders. The suicide–work relationship might have relevance in the ongoing debate on the extent to which exposure to socioeconomic adversity is a causative factor in the development of suicidal behavior. As the economic situation and economic policy decisions might have a tremendous psychological and social impact on a population, the negative consequences of being not in the labor force, particularly being unemployed, retired or a homemaker, should be considered early enough by governments and counteracted. A suicide prevention approach should include several levels of suicide prevention, such as cooperation with primary care physicians, information for the general public and cooperation with community facilitators. In employed persons, adverse psychosocial working conditions indicate to be important risk factors contributing to suicidal behavior. Modification of working conditions, helping workers cope with work stress or reducing particular work stress levels, improve work attitude, self-efficacy, and work engagement could possibly decrease job strain (Koolhaas et al., 2010) and prevent adverse health outcomes, such as suicide.
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Acknowledgments Barbara Schneider received research funding as young scientist for the project “Psychopathological, sociodemographic, psychosocial, and work-related risk factors for suicide” from the faculty representative committee of the Faculty of Medicine, Johann Wolfgang Goethe-University of Frankfurt/Main. Furthermore, “Nachlaß Martha Schmelz”, part of the university foundation of Frankfurt am Main, supported the research project.
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Contents lists available at ScienceDirect
Psychiatry Research j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / p s yc h r e s
Impact of employment status and work-related factors on risk of completed suicide A case–control psychological autopsy study Barbara Schneider a,⁎, Kristin Grebner a, Axel Schnabel b, Harald Hampel a, Klaus Georgi a, Andreas Seidler c a b c
Department of Psychiatry, Psychosomatic Medicine, and Psychotherapy, Goethe-University, Frankfurt/Main, Germany Centre of Legal Medicine, Goethe-University of Frankfurt/Main, Germany Institute of Occupational and Social Medicine, Technical University of Dresden, Germany
a r t i c l e
i n f o
Article history: Received 8 February 2011 Received in revised form 19 July 2011 Accepted 26 July 2011 Keywords: Case–control study Psychological autopsy Unemployment Working conditions Completed suicide Outside occupation
a b s t r a c t The objective of this study was to determine the impact of work-related factors on risk for completed suicide. Psychiatric disorders and socio-demographic factors including work-related factors were assessed by a semistructured interview using the psychological autopsy method in 163 completed suicide cases and by personal interview in 396 living population-based control persons. Unemployment (in particular, for more than six months), (early) retirement, or homemaker status were associated with highly significantly increased suicide risk, independently of categorized psychiatric diagnosis. In addition, adverse psychosocial working conditions, such as monotonous work, increased responsibility and pronounced mental strain due to contact with work clients, significantly increased suicide risk as well, again independently of categorized psychiatric diagnosis. These findings demonstrate that negative consequences of unemployment, homemaker status with no outside occupation, or (early) retirement, as well as adverse psychosocial working conditions, present relevant risk factors contributing to suicidal behavior, independently of diagnosed psychiatric disorders. Employment and a positive modification of working conditions, may possibly be preventive to important adverse mental health outcomes, including suicidality. © 2011 Elsevier Ireland Ltd. All rights reserved.
1. Introduction A comprehensive number of epidemiologic studies demonstrated that suicide risk is not only impacted by categorized diagnostic psychiatric disorders and aggressive-impulsive behavior, but also by various social cofactors, such as adverse marital status and employment status (Yoshimasu et al., 2008). Furthermore, socio-economic events, such as economic crisis, are known to produce important fluctuations in suicide mortality with variations between countries with different economic and social conditions; this has recently been shown for Asian countries (Chang et al., 2009). Today, during times of economic dysbalance, uncertainty, and crisis, the relation between unemployment and risk of suicide as well as work-related factors and suicide is getting more significant, receiving increasing media attention, particularly regarding employee suicides. In controlled psychological autopsy studies, unemployment was associated with suicide with an up to nine-fold increased risk (Foster et al., 1999; Cheng et al., 2000; Gururaj et al., 2004; Chen et al., 2006), even after adjustment for axis I disorders (Foster et al., 1999) and
⁎ Corresponding author at: Center of Psychiatry, Department of Psychiatry, Psychosomatics, and Psychotherapy, Goethe-University Frankfurt/Main, HeinrichHoffmann-Str. 10, D-60528 Frankfurt/Main, Germany. Tel.: + 49 69 6301 4784; fax: + 49 69 6301 5290. E-mail address: [email protected] (B. Schneider). 0165-1781/$ – see front matter © 2011 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.psychres.2011.07.037
other co-variables (Chen et al., 2006), or combining unemployment and household duties (Khan et al., 2008), being a homemaker, retired or unemployed (Phillips et al., 2002), or combining unemployment and sick leave (Almasi et al., 2009). Moreover, being unemployed or retired was identified as risk factors for suicide in individual (Johansson and Sundquist, 1997; Lewis and Sloggett, 1998; Kposowa, 2001; Blakely et al., 2003; Ahs and Westerling, 2006; Agerbo, 2007) and in register- or census-based cohort studies (Blakely et al., 2002; Qin et al., 2003; Agerbo, 2005). The link between unemployment and suicide was frequently investigated (see Schneider, 2003). However, relatively few studies have investigated the link between working conditions and work attitude and suicide: Adverse working conditions and high workrelated stress were associated with increased suicide risk in cohort studies of particular occupational groups; these studies were carried out in the US (Feskanich et al., 2002), Canada (Ostry et al., 2007), and Japan (Tsutsumi et al., 2007). Insurance and legal reports indicated that long working hours, heavy workloads, and low social support might be related to suicide in Japan (Amagasa et al., 2005). A recent Hungarian controlled psychological autopsy study revealed an association between concern over work prospects and suicide (Almasi et al., 2009). This scarcity of studies investigating the link between working conditions and suicide is surprising, as prospective analyses have found that job characteristics and work stress appear to precipitate subsequent burnout, depressive symptoms, and risk of successive
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psychiatric diagnosis (Paterniti et al., 2002; Borritz et al., 2005; Wang, 2005; Melchior et al., 2007; Wieclaw et al., 2008). In order to investigate potential conditions increasing suicide risk, additional research is required (Ohayon, 2009). In spite of the huge number of studies regarding aspects of the work–suicide relationship several salient questions remain open. Although elevated suicide risk was repeatedly found for unemployed and retired people, suicide risk for other people without work, such as homemakers, has been hardly investigated in population-based studies. Furthermore, it remains unclear which particular sources of job stress actually affect suicide risk for the individual. The objective of this study was to determine aspects of employment status and work-related factors on suicide risk and to assess how the extent of work-related factors, such as employment status and relevance of psychosocial work load, affect the risk of completed suicide. Specifically, we hypothesized that being unemployed or being retired would increase suicide risk, even independently of psychiatric diagnosis and marital status. 2. Methods 2.1. Study population All 263 suicides (mean age 50.9 [S.D. 19.6] years; 66.2% males) who died in the Frankfurt/Main area (864,253 inhabitants on December 31, 1999) in 1999 and 2000 were included in the study. All suicides were classified as certain suicides (ICD-10 X 60–X 84) by the Center of Forensic Medicine, which must examine all deaths by unnatural or uncertain causes in this region. The relatives of 163 suicides (mean age 49.8 [S.D. 19.3] years; 64.4% males; men: 48.4 [S.D. 19.4] years; women: 52.1 [S.D. 19.1]years) were interviewed using the psychological autopsy method (Isometsä, 2001) with a semistructured interview 8.5 [S.D. 6.8]months after the suicide. Key informants of the deceased were spouses (35%, n = 57), adult children (21%, n = 34), parents (18%, 20 mothers and 9 fathers) and other relatives and friends (26%, n = 43). Sixty-three percent of the interviewees lived with the deceased. Persons who had been documented as “closest relatives” in the official police report were accepted as proxy interviewees. The study sample and the study design are described in detail elsewhere (e.g. Schneider et al., 2009). In addition, out of the 685 population-based controls contacted, 396 persons (mean age 51.6 [S.D. 17.0] years; 55.8% males, response rate 57.8%, matched to the suicides by residential area, age, and gender, frequency matching) were personally interviewed. The controls were chosen by ‘random digit dialing’. Control persons were also asked to give their permission for repetition of the interview, for interviews by two interviewers, and for asking a close relative or friend to give an interview about the control person himself or herself. 2.2. Instruments and diagnostic procedure A semi-structured interview, a modified and translated version of the interview applied in the National Suicide Prevention Project in Finland including differentiated questions about employment status and working conditions (Henriksson et al., 1993a, 1993b), and the Structured Clinical Interview for DSM-IV Axis I and II disorders (lifetime; SCID-I, SCID-II, German version) were carried out with control persons and with informants about the suicide cases. Dementia and other cognitive disorders were diagnosed using the DSM-IV algorithm. The set of work-related questions was based on questions suggested by Leino and Hänninen (1995), but shortened and supplemented by a question concerning psychic strain through contact with clients at work as applied by Seidler et al. (2003). For every job held, the participants had to assess psychosocial aspects of the work environment on a scale ranging from 1 (for low stress) to 6 (for high stress). The assessment of interrater reliability, test-retest reliability, and agreement between personal and informant's interview for DSM-IV axis I and axis II diagnoses, employment status, working conditions and socio-demographic features were measured using kappa statistics, Kendall's tau, and Intraclass correlation coefficients (ICC; one-way (Shrout and Fleiss, 1979)). These coefficients were found to be at least good for interrater reliability and test–retest reliability. Comparison of personal and relative's interview among control subjects generated kappa coefficients above 0.79 for most axis I and above 0.65 for most personality disorder diagnoses (Schneider et al., 2004). Kappa coefficients were excellent for most work-related variables (≥0.83) and at least moderate for the variable ‘student’ (kappa = 0.65) and for ‘anticipation of changes in the future’ and direction of anticipation (kappa = 0.66, each). Sensitivity and specificity were high for all assessed variables (≥ 80%) with exception of ‘student’ (sensitivity = 50%). For psychosocial working conditions, dimensional scores by personal and informant's interview were significantly correlated (tau ≥ 0.63). The study protocol was approved by the ethics committee of the Medical Faculty of the University of Frankfurt/Main and carried out in accordance with the ethical standards laid down in the Declaration of Helsinki. Written informed consent was obtained by all interviewees after the aims of the study and all procedures had been fully explained.
2.3. Statistical analyses The statistical analyses were performed with SPSS version 17.1. Binary logistic regression analysis was used to estimate the odds ratios (OR) and their 95% confidence intervals (95% CI) for the association between suicide and the assessed risk factors. The unconditional logistic regression analysis was adjusted for age group and gender and in further models also for axis I and axis II disorders, and living together with one's partner, respectively. With the exception of the set of work-related questions (Leino and Hänninen, 1995), all variables were introduced as categorized variables in the analyses. The variables assessing psychosocial factors at work were linearly introduced into the logistic regression models. As the association between psychosocial factors at work and suicide risk might be nonlinear, we also performed logistic regression analysis with a linear and (additionally) a squared term of the psychosocial factors. Odds ratios and confidence intervals were not calculated for variables with fewer than five subjects in suicides or in controls in one of the subgroups. Furthermore, adjusted odds ratios were not calculated for variables with fewer than two subjects in one of the subgroups for axis I disorders or personality disorders in the suicide or in the control group. The level of statistical significance was set at α = 0.05 (two-sided).
3. Results As shown in Table 1, unemployment revealed the most increased risk of suicide. Twenty-one suicides (84% of all unemployed suicides) and four control persons (80% of all unemployed controls) were unemployed for a period of more than 6 months. After adjustment for psychiatric disorders and partnership, the estimated suicide risk was about three times higher for retired people than for employed persons (OR = 3.0; 95% CI 1.1–8.2). Being temporarily employed and being self-employed did not reveal significant odds ratios (Table 1). Being ‘without work’ was associated with an about three times elevated risk (Table 1), even after adjustment for psychiatric disorders and partnership (OR = 3.2; 95% CI 1.5–7.0). A significantly increased risk was associated with disability pension (Table 1). Stratification for age groups showed very similar results for the age group 31 to 60 years as for the entire sample with even higher odds ratios for unemployment (OR = 21.8; 95% CI 3.4–140.0) and for being ‘without work’ (OR = 2.8; 95% CI 1.2–7.0; odds ratios after adjustment for axis I disorders, personality disorders and status of cohabitation). Difficulties with sick leave or retirement significantly increased suicide risk (OR = 3.5; 95%
Table 1 Association between suicide and current work circumstances, status of employment, and kind of retirement. Control persons (N = 396) Kind of employment (Self-)employed Unemployed Retired Student Full-time homemaker On sick leave Status of employment Permanently For a limited period, temporarily Self–employed Without work Kind of retirement Not retired, old age or widow's pension Disability pension Unemployment pension
Suicides (N = 163)
OR (95% CI)
219 (55.3%) 5 (1.3%) 124 (31.3% 13 (3.3%) 33 (8.3%) 2 (0.5%)
66 (40.5%) 24 (14.7%) 51 (31.3%) 11 (6.7%) 9 (5.5%) 2 (1.2%)
1 16.1 (5.9–44.1) 2.2 (1.1–4.3) 2.3 (0.9–5.9) 1.2 (0.5–2.8) –
176 (44.4%) 10 (2.6%)
51 (31.3%) 6 (3.7%)
1 2.3 (0.8–6.8)
33 (8.3%) 177 (44.7%)
9 (5.5%) 97 (59.5%)
0.9 (0.4–2.1) 3.1 (1.9–5.0)
381 (96.2%)
146 (89.6%)
11 (2.8%) 4 (1.0%)
15 (9.2%) 2 (1.2%)
1 4.0 (1.7–9.1) –
Eight persons were students and employed and included in employed, 3 persons were housewives and employed and included in employed, 1 person was unemployed, but had a temporary job and were included in employed, 5 people were on sick leave, although employed or own business and were included in employed. OR: adjusted for sex and age groups; –: not calculated because of low sample size.
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Table 2 Association between suicide and level of education and professional training. Control persons (N = 396) Level of education High (at least twelve years) Middle Low (less than ten years) Level of professional training University, university of applied sciences Apprenticeship, vocational college Semi-skilled, no professional training Not applicable (e.g. young people)
Suicides (N = 163)
OR (95% CI)
OR (95% CI)*
OR (95% CI)**
1 1.9 (1.1–3.3) 3.2 (2.0–5.1)
1 1.7 (0.8–3.6) 2.3 (1.1–4.6)
1 1.7 (0.8–3.7) 2.4 (1.2–4.8)
1 2.4 (1.4–4.2) 8.3 (4.2–16.5) 4.0 (1.2–12.6)
1 2.3 (1.1–5.1) 12.7 (4.2–38.2) 6.7 (1.4–32.6)
1 2.4 (1.1–5.4) 13.4 (4.4–41.0) 5.3 (1.0–27.8)
a
171 (43.2%) 89 (22.5%) 136 (34.3%)
41 (25.6%) 35 (21.9%) 84 (52.5%)
b
c
107 (27.1%) 242 (61.3%) 37 (9.4%) 9 (2.3%)
18 (11.0%) 90 (55.9%) 45 (28.0%) 8 (5.0%)
OR: adjusted for sex and age groups; *additionally adjusted for axis I and personality disorders; **additionally adjusted for axis I disorders, personality disorders and status of cohabitation. a 3 Cases missing. b 1 Control missing. c 2 Cases missing.
CI = 1.1–11.5), but this association lost its statistical significance after adjustment for psychiatric disorders and partnership (OR = 2.5; 95% CI = 0.6–11.3). After adjustment for different axis I disorders and personality disorders, the odds ratios remain nearly the same as the crude odds ratios and as the odds ratios adjusted for all axis I disorders. Analyses with further adjustment for other variables than mental disorders and status of cohabitation, such as treatment history, use of medical and non-medical drugs, smoking, having children, and income, were performed. Adjustment for these variables did not alter the results and therefore are not presented here. Low educational level was associated with a more than twofold increased suicide risk. Suicide risk was particularly highly elevated in persons who were only semi-skilled or had no professional training (Table 2). In working people, suicide risk was about three times higher in those with at least three jobs within the last 5 years than in those with only one job in the last 5 years (suicides: 25.6%, control persons: 9.7%, OR = 3.0; 95% CI = 1.2–7.6, after adjustment for psychiatric disorders and partnership OR = 2.6; 95% CI = 0.8–8.9). Suicide victims had more often experienced more monotonous work, higher responsibility and higher psychic strain due to contact with clients at work according to their relatives' information. The suicide risk was increased, even after adjustment for psychiatric disorders and partnership (Table 3). Being unsatisfied with colleagues and boring work were associated with increased suicide risk; these associations lost their statistical significance after adjustment for psychiatric disorders and partnership (Table 3). The analyses with the squared terms (additionally to the linear terms) revealed significantly elevated odds ratios for squared time pressure and squared satisfaction with colleagues (no table). In terms of anticipation of changes in the future, 35.6% of the control persons and 27.7% of the suicides anticipated changes. Ninety
percent (89.9%) of the controls and 27.7% of the suicides deemed the anticipated changes to be positive; anticipation of changes in the future showed significantly reduced suicide risks (OR = 0.5; 95% CI = 0.4–0.9; after adjustment for psychiatric disorders and partnership OR = 0.4; 95% CI = 0.2–0.7). In the multivariate analysis (Backstep-WALD) being unemployed, retired, a homemaker, suffering from axis I disorders, personality disorders or not cohabitating remained as significant independent risk factors in the final model with the highest odds ratios for ‘unemployed’ (Table 4). If the various groups of axis I disorders were separately included in the multivariate analysis (BackstepWALD), being unemployed always revealed significantly increased odds ratios with the lowest odds ratio (OR = 12.4; 95% CI 4.4–34.7) after having introduced substance use disorders in the model (OR = 3.0; 95% CI 1.9–4.7). 4. Discussion Our most important finding is that being without work (including all people who were not in the labor force, i.e. not in paid employment or self-employment) was strongly, more than two-fold, associated with increased suicide risk with a more than 16-fold increased risk for unemployment, an about three-fold increased risk for being retired and an about six-fold increased risk for being a homemaker. Furthermore, low levels of educational training, low levels of professional training, and frequent job fluctuations, e.g., having three or more jobs in the last 5 years, were associated with increased suicide risk. Adverse working conditions, such as high responsibility or monotonous work, slightly increased suicide risk. Adjustment for axis I disorders and personality disorders and adjustment for partnership do not substantially alter the effect of ‘not working' on completed suicide.
Table 3 Association of psychosocial factors at work and suicide (only [self-]employed). Median [quartiles]
Variety of work (1 = very varied work to 6 = very monotonous) Interestingness of work ((1 = very interesting to 6 = very boring) Satisfaction with superiors (1 = very satisfied to 6 = very dissatisfied) No superiors(= 0) included in analysis Satisfaction with colleagues (1 = very satisfied to 6 = very dissatisfied) No colleagues included in analysis Psychic strain through contact with clients (1 = very little to 6 = very much) No clients included in analysis Time pressure (1 = very little to 6 = very much) Responsibility (1 = very little to 6 = very much)
Control persons
Suicides
2 [1; 3] 2 [1; 3] 2 [2; 3] 2 [1; 3] 2 [1; 2] 2 [1; 2] 2 [1; 3] 0 [0; 3] 3 [2; 5] 2 [1; 3]
3 3 3 2 2 2 2.5 1 3 4
[2; 4.5] [1; 4.25] [1.5; 5] [1; 5] [1; 3] [1; 3] [1; 4] [1; 4] [1; 5] [1; 5]
OR (95% CI)
OR (95% CI)*
OR (95% CI) **
1.9 (1.4–2.5) 1.8 (1.3–2.3) 1.3 (1.0–1.7) 1.2 (1.0–1.6) 1.5 (1.0–2.1) 1.5 (1.0–2.0) 1.3 (0.9–1.7) 1.5 (1.2–1.9) 1.0 (0.8–1.2) 1.6 (1.2–2.0)
1.5 (1.1–2.0) 1.3 (1.0–1.8) 1.1 (0.8–1.5) 1.1 (0.9–1.4) 1.2 (0.8–1.8) 1.2 (0.8–1.8) 1.1 (0.7–1.6) 1.6 (1.2–2.1) 0.9 (0.7–1.2) 1.4 (1.1–1.8)
1.5 1.3 1.1 1.1 1.2 1.3 1.1 1.6 0.9 1.4
(1.1–2.0) (0.9–1.8) (0.8–1.5) (0.9–1.4) (0.8–1.9) (0.8–1.9) (0.7–1.6) (1.2–2.1) (0.7–1.2) (1.1–1.8)
OR: adjusted for sex and age groups; *additionally adjusted for axis I and personality disorders; ** additionally adjusted for axis I disorders, personality disorders and status of cohabitation; the ordinal values (1 to 6) for the psychosocial factors were included as continuous variables in the logistic regression model. The stated OR gives the risk elevation per 1 point increase of a single psychosocial factor.
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Table 4 Logistic regression analysis of association between work circumstances, Axis I disorders, personality disorders, cohabiting, and suicide (Backstep-WALD). OR (95 % CI) Unemployed Retired Homemaker Axis I disorder Personality disorder Not cohabitating
16.8 (3.7–77.0) 2.3 (1.1–4.5) 5.3 (1.3–21.7) 13.2 (6.1–28.9) 4.8 (2.6–8.9) 3.0 (1.6–5.6)
OR: adjusted for sex and age groups; variables included in the analysis: employment status, axis I disorders, personality disorders, and partnership.
Our study shares the general methodological strengths and weaknesses of controlled psychological autopsy studies. A major strength of this study design is that information of working conditions at the exact time of the suicide is gathered. These methodological considerations, such as retrospective information and lack of nonresponder analysis of interviewees of suicides, have been described in detail in previous articles (e.g., Schneider et al., 2009). With respect to the present topic, some particular limitations have to be addressed: (a) Our response rates were relatively low, but similar to those noted in several Western controlled psychological autopsy studies (e.g., Hawton et al., 2002). Due to data protection regulations in Germany, we could not perform non-responder analyses in our sample for estimation of selection effects. However, we have no hints for selection bias; Prevalences of psychiatric disorders and frequency of employment status correspond to those of the general population of Germany (http://www.frankfurt.de/ sixcms/media.php/678/2002_2_Mikrozensus1997_2001.pdf). (b) For some occupational factors (particularly early retirement and psychosocial workload), additional adjustment for psychiatric disorders led to decreased odds ratios in our study. This could be at least partly explained by a potential overadjustment: Overadjustment is defined as control for an intermediate variable on a causal path from exposure to outcome. As unemployment represents a potential risk factor for psychiatric disorders, and as psychiatric disorders represent risk factors for suicide, psychiatric disorders might partly constitute an intermediate factor on the causal pathway from unemployment to suicide. The causality of the associations between psychiatric disorders, unemployment, working conditions and suicide are not yet clarified (Blakely et al., 2003) and the association between unemployment and suicide in subjects with psychiatric illness is small (Agerbo, 2005). Unfortunately, we were not able to clarify the temporal sequence of unemployment and psychiatric disorders in our retrospective case–control study definitely. Therefore, additional adjustment for psychiatric disorders might have led to an underestimation of the increased suicide risk of unemployed people. Mental illness might be a step on the causal pathway from social position to suicide (Agerbo et al., 2007) and, furthermore, a mediating factor could be that treatment and aftercare perhaps focus on the larger proportion of patients who are the most disadvantaged. Regarding the temporal sequence of unemployment and psychiatric illness, our data do not provide hints that mental disorder was followed by unemployment or that unemployment was higher in individuals with more severe illness, e.g. in major depression with recurrent episodes than with a single episode. However, mental disorders might have been less severe in control persons than in suicides. This could have biased the results. (c) In our study, agreement between proxy and self-interview was high for psychiatric diagnoses (Schneider et al., 2004) and at least moderate for work-related factors among control subjects (see above). As the relatives were not aware of symptoms or would overestimate them, exposure might be misclassified. This error may also bias the results. However, this misclassification could only explain a small part of the overall strong effect. (d) Participation in the labor force is different for men and for women in the population of Frankfurt (http://www.frankfurt.de/sixcms/media.php/678/ 2005_1_%20Kurzinfo_Arbeitslosigkeit%202000-2005.pdf) and in our study population; unemployment (Kposowa, 2001; Qin et al.,
2003) and work-related factors might have different impact on male and female suicide risk. However, analyses stratified for gender showed very similar results for males and females; due to the small sample size we decided against presenting these findings. (e) As suicides are rare events and our study population was restricted to the German metropolitan Frankfurt (Main) area, the sample size of our study is relatively small. Due to the small sample size odds ratios were unstable with partly relative wide confidence intervals; thus, precise risk estimation is limited and chance could be an alternative explanation of the observed associations; therefore, completely unequivocal conclusions could not always be guaranteed. However, in spite of these possible shortcomings, the associations between unemployment, other work-related factors, and suicide remain clearly obvious. (f) As the relatives were not aware of symptoms and problems or would overestimate them, exposures might be misclassified. This error may also bias the results. However, this misclassification might only explain a small part of the effects. Consistent with general population-based psychological autopsy studies including all age groups educational underachievement (Zhang et al., 2004) and being unemployed (Foster et al., 1999; Cheng et al., 2000; Gururaj et al., 2004) were identified as predictors for suicide, even after adjustment for psychiatric disorders, which had often been seen as one of the most important links between unemployment and suicide (Chan et al., 2007). In our study, the odds ratio for unemployment was higher than in all other controlled psychological autopsy studies and independent of psychiatric disorders and partnership status. As most of the suicides were not fired or given notice within the last three months before committing suicide (Kõlves et al., 2006), recent job loss could not be the cause for this high suicide risk. In our study, most suicides and control persons were unemployed for a period of more than six months. This is similar to the data for Frankfurt (Main) (http://www.frankfurt.de/sixcms/ media.php/678/2002_2_Mikrozensus1997_2001.pdf) and Germany, where in general the majority of unemployed people are long-term unemployed persons (Karr, 2002), which is usually associated with higher suicide risk than short-term unemployment (Classen and Dunn, 2011). However, contrary to our study, long-term unemployment is defined as unemployment lasting for longer than one year in Germany. Long-term unemployment is associated with diminished financial security and status and a considerable source of social distress, family tensions, and loss of self-esteem. Furthermore, there might by other variables, which are causal to both, unemployment and suicide. Poor education and low level of professional training might be such factors; both were significantly associated with unemployment in our study (data not shown). Moreover, various other factors, such as unemployment insurance or social isolation might be involved in the pathways between unemployment and suicide and influence the association between unemployment and suicide. Furthermore, it must be mentioned that our study was carried out in the area of Frankfurt/Main and the data were collected during the years 1999 and 2000. Economy was relatively stable in this period and moreover, the area of Frankfurt/Main has a relatively stable economy and usually low unemployment rates, even in periods of mass unemployment and mass-layoffs. Therefore, unemployment in our study might be very different from unemployment in studies in periods and/or regions with mass unemployment, as suicide risk might be increased by mass unemployment and mass-layoff (Classen and Dunn, 2011). In periods of mass unemployment monetary and health policies might affect suicide. In economically stable periods and regions, in unemployed persons more individual interventions are needed in order to reduce suicide risk. Estimated suicide risk for full-time housewives/house husbands was almost fivefold increased. This high suicide risk of full-time homemakers is compatible with a potential protective effect of being employed against risk of suicide. These findings are supported by those of the SUPRE-MISS study having found that being a homemaker
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was associated with a higher risk for repeated suicide attempts (da Silva Cais et al., 2009). In agreement with the results of a controlled psychological autopsy study in people aged 60 and older (Harwood et al., 2006), being retired doubled suicide risk. Although retirement was repeatedly found as a recent life event in elderly suicides compared to younger ones (Pompili et al., 2008), suicide victims were not more frequently retired in the last three months (Kõlves et al., 2006). Thus, increased suicide risk caused by retirement as recent life event could be ruled out. As the increased suicide risk among early retired people is mainly not explained by disability pension due to psychiatric disorders, other disorders leading to disability pension should be considered as a possible explanation of the increased suicide risk of early retired people. Furthermore, several contributory factors might be related to retirement, such as social identity (Michinov et al., 2008), which could reflect underlying factors for suicide risk. Although we could not prove that adverse working conditions were causally related to suicide using the present study, in terms of working conditions, increased burden of job responsibility, much social strain through client contacts, and very repetitive monotonous work were associated with slightly increased suicide risk, independently of psychiatric condition and living with one's spouse. Despite methodological differences including other variables for assessment of working conditions, our results are supported by findings in saw mill workers (Ostry et al., 2007) and male Japanese workers (Tsutsumi et al., 2007), which reported that low psychological demand and low control at work were associated with increased suicide risk. However, the association between stress at work and suicide risk might be nonlinear (e.g. U-shaped), and additional stress at home might modify suicide risk (Weinberg and Creed, 2000; Feskanich et al., 2002). Stress at home was not included in our analyses; however, our results indicate that the relationship between psychosocial working conditions and suicide might be non-linear (super-linear) for some psychosocial work-related variables, e.g. for time pressure. Furthermore, self-rating of psychosocial working conditions might be prone to substantial recall bias, such as denial of stress as a coping mechanism. Moreover, some variables representing “classical” occupational stress models, such as included in the job demand/control model (Karasek et al., 1981) or in the effort/ reward imbalance model (Siegrist et al., 1990), were not assessed in the present study. Working conditions were only assessed in employed people. Past adverse working conditions might have led to psychic or physical impairment; however, we did not assess temporal sequences of these and other variables which might be contributing factors in the complex pathways to suicide. Although it remains open to which extent our results from a small sample size in a defined region and time period can be generalized to other cohorts or another social context, our results demonstrate that employment status, in particular unemployment and being retired, are important risk factors for suicide, independently of psychiatric disorders. The suicide–work relationship might have relevance in the ongoing debate on the extent to which exposure to socioeconomic adversity is a causative factor in the development of suicidal behavior. As the economic situation and economic policy decisions might have a tremendous psychological and social impact on a population, the negative consequences of being not in the labor force, particularly being unemployed, retired or a homemaker, should be considered early enough by governments and counteracted. A suicide prevention approach should include several levels of suicide prevention, such as cooperation with primary care physicians, information for the general public and cooperation with community facilitators. In employed persons, adverse psychosocial working conditions indicate to be important risk factors contributing to suicidal behavior. Modification of working conditions, helping workers cope with work stress or reducing particular work stress levels, improve work attitude, self-efficacy, and work engagement could possibly decrease job strain (Koolhaas et al., 2010) and prevent adverse health outcomes, such as suicide.
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Acknowledgments Barbara Schneider received research funding as young scientist for the project “Psychopathological, sociodemographic, psychosocial, and work-related risk factors for suicide” from the faculty representative committee of the Faculty of Medicine, Johann Wolfgang Goethe-University of Frankfurt/Main. Furthermore, “Nachlaß Martha Schmelz”, part of the university foundation of Frankfurt am Main, supported the research project.
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