The purpose of this study was to investigate the epidemiology of suicide and associated risk factors in suicide cases admitted to the emergency department of Zahedan Khatam-Al-Anbia Hospital. The results ofthis study showed that the majority of cases were young women with the low education levels, low income and more than three quarter of the cases had a history of mental disorders. The method most frequently used for suicide was burning and the majority of cases committed suicide at home and most likely at noon time. Almost one third of the cases occurred during spring time and half of the cases were fatal. Spouse violence and dispute accounted for half of the suicide cases followed by drug abuse.
Although suicide is a complex human behavior, a range of socio-demographic factors has been shown to be associated with an increased risk of suicidal behavior in different social and cultural settings. More than 40% of suicide cases in this study were in the age group of 16 to 25 years. This is consistent with the findings of similar studies from Iran (
6,
11-
13) and other countries (
14,
15), in majority of which it has been reported that younger subjects account for a greater proportion of suicide cases. Study of the global patterns of mortality in young people has shown that suicide is the second leading cause of death in the 15-19 years age group (
16). Analysis of data from studies on suicide attempts carried out in the Islamic Republic of Iran between 1981 to 2007 showed that the mean age of suicide attempters was 25 years (
12). A study of suicide attempts in Hamedan province reported that the suicide attempt rate was highest in the age group of 15-24 years with an incidence rate of 536 cases per 100000 population (
6). Similarly, more than 66.2% of the suicide cases admitted to the emergency department of a hospital were between 16 to 25 years old (
13). The results from another study showed that the mean age of the suicide cases was 19 years for men and 24 years for women (
11).
Suicidal behaviors in young people are thought to be linked to adverse life events and a wide range of risk factors have been identified (
17). These include: social and educational disadvantages; childhood and family adversity; psychopathology; individual and personal vulnerabilities; exposure to the stressful life events and circumstances; and social, cultural and contextual factors.
Almost half of the suicide cases in our study were a result of family conflicts, with spouse violence accounting for more than a third of the total suicide events. Most common stressful life events that immediately precede the suicide attempts are the interpersonal conflicts mostly linked to relationships with spouses or partners (
18). Suicidal behaviors are one of the major contributors to the global burden of disease among women. Evidence from the WHO multi-country study on women's health and domestic violence against women has shown that events such as intimate partner violence (IPV), non-partner physical violence, ever being divorced, separated or widowed, childhood sexual abuse and having a mother who had experienced IVP were the most consistent risk factors for suicide attempts in women(
19). In a study of the socio-cultural contexts of suicide attempts among women in Iran, family conflicts, marriage and love, social stigma, pressure of high expectations, and poverty were the main issues identified as the suicide precipitating factors in women (
20).
Exposure to intimate partner violence is an event that is experienced by women living in low- and middle-income countries on a daily basis, being reported by 15%-71% of women over their lifetime (
21). There is an evidence of a consistently strong relationship between the intimate partner abuse and suicide attempts in women (
19). Another study has found that the physical violence to be associated with more than a four-fold increase in suicidal thoughts in women (
22). Surprisingly, only 27% of the women subjected to spouse violence would disclose this to anyone (
22), and they are less likely to seek medical advice (
19).
A disrupted family environment and parent-adolescent conflict have been found to be associated with the suicide attempts (
23). There is some evidence that the negative relationships with either or both parents significantly increase the risk of suicide and/or depression (
24). In our study, a total of 15% of the suicide cases were a result of parent-adolescent conflicts and family fanaticism that put them at an increased risk of suicidal behavior. The results from a systemic review of social factors associated with suicide attempts in Iran showed that the family conflicts was the most frequent cause of suicide with an average prevalence of 32% (
25). The prevalence in the studies reviewed ranged from 55% that was reported from Gilan province to 12% that was observed in Khorasan Razavi province. Moreover, the overall prevalence of marital problems was found to be 26%. A study of the self-poisoning suicide attempts among students showed that 21.08% of the subjects had a history of child abuse and 22.5% came from a broken family (
26). A quarrel with a family member, a relative, and/or a friend was also found to be the most common precipitating factor (74.4%) for suicide attempts by burning (
27). Another study reported that almost half of suicide attempts was a results of family conflict (
28). On the other hand, giving credit to the importance of the family appears to be associated with lower levels of parent-adolescent conflict, hence protecting the younger generation from suicide attempts. In comparison with disrupted family environments, adolescents living in an atmosphere of high family cohesion and low conflict are significantly less likely to attempt suicide (
23).
We found seasonal variations in suicide attempts. This is consistent with studies from western countries (
29,
30) and also some studies from Iran (
6,
31-
33). An Iranian study of the suicide cases from 2006 to 2010 across the country showed that the completed suicides were more likely to happen in summer and they were least prevalent in winter (
32). However, in some studies, the clear pattern of seasonality has been identified for only suicides committed by the violent methods (
29). As compared with females, the relationship between seasonal factors and violent suicides has been found to be stronger in male suicides (
29). There are some evidence of the relationship between season and changes in human mood (
34). This could be partly explained by the seasonal factors including daily sunshine and global radiation that influence the regulation of the serotonergic transmission and serotonin-1A receptor binding in limbic regions of the brain (
35).
Other socio-demographic factors related to suicidal behavior include the economic constrains and educational failure. In this study, a greater proportion of the suicide cases had a poor or medium income and those with low income were more likely to die when attempting suicide. This is in agreement with the results from a systemic review of studies on suicide in Iran that estimated that 12% of the suicide attempts were linked to economic constrains, ranging from 4% to 40% in different studies (
25) .
One fifth of cases investigated in this study had no education and the educational level of almost half of them was primary school. This is comparable with the proportions reported in studies carried out in other parts of Iran (
13,
36). In a survey of suicide by burning in Tehran, for instance, 26.2% of the cases were illiterate (
33). However, in some studies people with high school and higher educational levels dominated the suicide cases (
11). Moreover, in a systemic review of suicide studies in Iran, the prevalence of educational failure among cases with suicide attempts on average was found to be 5% (
25).
Overall, 18% of the suicide cases in this study were related to drug abuse. This is in agreement with the findings from similar studies conducted in Kerman and Hamadan provinces that the proportions of drug abuse in the suicide cases admitted to the emergency department were16% and 16.3%, respectively (
11,
28). The relationship between drug abuse and suicide attempts could be partly explained by what is called "interpersonal theory" (
37). According to the theory, the repeated exposure to physically painful experiences such as injecting drugs leads to pain habituation, which is likely to entail the suicidal behavior. Harmful behaviors including suicide in people who are suffering from drug abuse is a common finding (
38). There is some evidence that the strength of association between drug abuse and suicidal acts depends on the type of the substance abused, with prescription drug abuse showing the strongest influence, followed by inhalant and cannabis abuse (
39). Moreover, it has been identified that subjects with the recent drug use are approximately 5 times more likely to use violent suicide methods as compared with those who did not report substance abuse (
40).
It has been hypothesized that the individuals who attempt suicide differ from those who complete suicide. In the present study, we compared these two groups in terms of socio-demographic and suicide-related characteristics. In a review of suicide data for the time period from March 2001 to March 2007 that were retrieved from health system databases of 41 Iranian medical universities, the prevalence of the completed suicides was 7.3%, which is much lower than what we observed in our study (
41). Moreover, a wide range of variations in the prevalence of case fatality among suicide cases across the country has been shown, changing between 2% and 25.3% (
11,
13,
28,
42). Given the fact that more than 90% of the cases included in this study were those who were referred from other districts and hence more likely to suffer from life-threatening complications that made them eligible for referral to more advanced and equipped centers at the provincial level, over-representation of those cases is most likely to have resulted in more fatal cases as compared with figures from different studies across the country. This was further substantiated by comparing burning (the most fatal method) with the non-burning suicide methods between the districts. For instance, 70% and 65% of the cases referred from Chabahar and Saravan districts used burning for a suicide act, which was more likely to succumb in spite of referral to an advanced center.
Low income, suicide attempts during summer time, and burning used as a method of suicide were more likely to be associated with fatal outcomes. We did not identify any gender differences in terms of suicide outcome, some studies have found a significant relationship between gender and fatal suicide (
7). The results from our study showed that suicide by burning was the most common method used in the completed suicide cases. However, in studies from different geographical regions of Iran a wide range of violent and non-violent methods are used, which seems to be influenced by the social and cultural context of the communities. For instance, a study on the case fatality rate of the different suicide methods in Ilam province showed that the most common suicide methods in fatal cases were hanging (75.4%) and self-immolation (68.3%), and the least fatal methods were drug ingestion and cutting (
42).
One of the limitations of this study was representativeness of the data used for analysis, as we used the information from only one referral hospital HIS and Forensic Medicine Department data. However, this hospital is a known burn and toxicology center and the suicide cases are more likely to be admitted to this hospital and only a small fraction of cases are admitted to other hospitals.
Suicide is a multi-factorial public health problem which results from an interaction between a wide range of demographic, social and cultural factors. Identifying the potential contributing factors and incorporating them into all preventive programs can help the public health authorities and policy-makers to mitigate the suicidal behaviors within communities.