Use of Occupational Knowledge to Commit Suicide

The World Health Organization (WHO) estimates that each year approximately one million people die from suicide, which represents a global mortality rate of 16 people per 100,000 [1]. Contrary to the overall tendency of suicide rate reduction in both Eastern and Western Europe, the Polish suicide rate in previous years trended strongly upwards [2]. In the last five years, the number of suicides in Poland has increased by more than 50% (from 4,087 in 2010 to 6,165 in 2014) [3].


Introduction
The World Health Organization (WHO) estimates that each year approximately one million people die from suicide, which represents a global mortality rate of 16 people per 100,000 [1]. Contrary to the overall tendency of suicide rate reduction in both Eastern and Western Europe, the Polish suicide rate in previous years trended strongly upwards [2]. In the last five years, the number of suicides in Poland has increased by more than 50% (from 4,087 in 2010 to 6,165 in 2014) [3]. Durkheim [4] considered the author of the definition of suicide, stated in his work "Le suicide" that, "suicide is applied to all cases of death resulting directly or indirectly from a positive or negative act of the victim himself, which he knows will produce this result". Suicide is not limited by age, sex or education. Experience tells us that people who decide to end their lives pursue the aim in spite of any external interventions. Suicide can be classified thus, completed (finished with death) and attempted suicides (a victim survives) [5,6].
Treatment for those whose attempts are unsuccessful is somatic (i.e. detoxification, surgical treatment of cut blood vessels) in the first instance, and psychiatric in the main. While somatic treatment usually gives positive effects, psychiatric treatment is not always successful and can lead to further attempts to end life [7]. Suicide is a harrowing phenomenon, the result of a dramatic human decision immersed in pain and desperation. Most people who commit suicide are deeply conflicted about death. They wish there was an alternative to committing suicide, but they just can't see one. Despite the popular concept that suicide is most often an impulsive act, recent research demonstrates that most suicides are not attempted impulsively and in fact involve a plan [8], which can take time to evolve and require lengthy preparations. solid substances); strangulation (by foreign body aspiration, drowning); and others (overheating, hypothermia, electrocution) [9,10]. The choice of suicide method is crucial if it is to have the intended effect. Besides the method being lethal, it must also be also accessible [11][12][13][14][15][16][17]. Professional knowledge is sometimes used to choose the suicide method [6,18].
The victims of suicide are not only the people who take their own lives. It has an extensive social impact involving not only the family, but friends, colleagues and therapists. As the effects spread among the population, the "public-health" approach focusing on identifying patterns of suicide and suicidal behaviors arises [19]. Suicide is preventable [1]. To protect an individual against this irreversible step, the thorough knowledge of risk factors is required. While an individual's risk depends on accessibility to means of suicide [11][12][13][14][15][16][17], reducing it is one way to reduce deaths [20][21][22][23].
The aim of this paper was to evaluate the incidence of suicides committed with the use of professional knowledge and to evaluate their lethal effect. The paper also presents four cases of individuals who used their professional knowledge to commit suicide. As a way to prevent suicide in risk prone professions, restricted access to means is discussed.

Example case 2
A couple of older, retired physicians who died because of an injection of a lethal dose of Insulin maxi rapid. Both individuals were seriously ill, the husband was diagnosed with urinary bladder cancer and his wife was tetraplegia. The injection sites (two in each individual) were found. In both, hypoglycemia was recorded as the reason of death (Figures 1-6).

Example case 3
A taxi driver found in a forest who gassed himself with exhaust fumes causing death by carbon monoxide intoxication.

Example case 4 (not autopsied)
An electrical engineer who connected himself to a power source using a timer. An examination revealed the presence of two copper plates, one of which was the front left side of the chest, the second

Material and Methods
A retrospective analysis of the autopsies performed in the Department of Forensic Medicine from 2010 to 2014 was carried out. All suicide cases were selected from the protocols. Information on the methods of suicide was extracted. Suicides committed with the use of professional knowledge or methods were analyzed. The research material was complemented by archive photographs taken at the scene of death during the medico legal inspection of the bodies.
It has to be emphasized that the presented figures do not reflect the actual number of suicide deaths in the region. They reflect only those cases that were the subject of an autopsy. The decision to carry out an autopsy rests solely with the prosecutor, however if the circumstances of death allow for an exclusion of third party contributions (definite suicide) then an autopsy does not have to be carried out. Non-autopsied cases are included in the statistics, and because of this we decided to present one more case. One which the prosecutor did not refer for autopsy. Nonetheless it was a case of the use of professional knowledge to commit suicide.

Results
A total of 1,908 autopsy protocols were evaluated, and 282 suicide cases (14.8%) were selected. The number of suicides increased from 49 cases in 2010 to 65 cases (+34%) in the years 2013 and 2014 ( Table  1). The most common ways to commit suicide are hanging and intoxication by pharmaceuticals, chemicals or natural poisons. Among the investigated suicides, 7 (2.6%) were committed using occupational knowledge or occupation-related means, Amongst them there were three cases where death was the result of having knowledge of and access to firearms (police officer, soldier, security officer); three cases of medical doctors who killed themselves by injection of insulin (a couple) or were intoxicated by anesthetic medication, and one taxi-driver who gassed himself with exhaust fumes causing death by carbon monoxide intoxication. Table 2 presents the distribution of these suicides between 2010 and 2014.

Example case 1
A policeman found in the vicinity of his patrol car with a gunshot in his head. His service weapon was found. The cause of death was traumatic brain injury.     One of the principal reasons for the high rates in these professions is easy access to proven methods (pharmaceuticals, guns) [11][12][13][14][15][16][17]. Several common characteristic features related to the respective occupational backgrounds can be noticed: availability of and easy access to the tools used, and the application of specialist knowledge or skills provided by the suicidal individual's occupational background [16].
Suicide has often been considered to be a "superseding intervening almost symmetrically was on his back. The copper plates were attached by elastic straps fastened with Velcro. Metal plates were attached to the wires connected to an electrical timer. In places the welded pipes were cleaned of corrosion to ensure good conductivity. The cause of death indicated an electric shock (Figures 7-9).

Discussion
Previous studies in Poland show an increasing trend in suicide rates [2]. Our study of the following years shows the tendency continuing upward. When discussing the results of the study, the questions that arose were "could the suicides have been prevented and if so, how?" A consistent relationship between occupation and suicide has been reported, with farmers, medical professionals, police officers and military personnel identified as the most "at risk" occupations [24,25].     cause that breaks the causative chain of events leading to death, thereby making it impossible to establish that any party other than the decedent could be liable for a suicide" [8]. Suicide attempts that involve a greater degree of prior planning also tend to be more medically serious. This implies that people who make medically serious attempts, including fatal attempts, had likely planned to do so ahead of time [8].
Although statistically the number of suicides committed with the use of professional knowledge is not high, their effect is always lethal.
The suicides using professional knowledge are dominated by physicians and professionals with access to firearms. Physicians because of their thorough knowledge of the drugs composition and properties, mechanisms, interactions, dosage and toxicology. And most of all easy access either to the pharmaceuticals or to prescriptions. All the above mentioned factors make doctors at higher risk of suicide than any other occupational group [26]. Medical professionals are more likely to use poisoning [17]. Professionals with the access to firearms like police officers, soldiers, security officers, commit suicide twice as often as others [17].
It has been proven that occupation influences suicide method [14]. Availability and access to means appeared to have influenced the method chosen [12,17]. One of the ways in which occupation might confer risk could be providing access to and familiarity with a particular method of suicide [17]. Access to potentially lethal means has a strong influence on the suicide rate [27].
Suicide occurs as a consequence not only of psychiatric disorders but also of impulsive moments of crisis [22]. For those who have access to firearms the action can be impulsive, whereas suicides by intoxication appear to be a rather long-planned. In professions where access to lethal means is inevitable, moderating the opportunity to commit suicide is crucially important [14]. The more sophisticated the method developed with the use of professional knowledge, the longer planning it required (case 4). Interfering with planning would seem to be a more effective way of preventing suicide than restricting access to means. This study was limited by two particular aspects. Firstly, that only the autopsied suicide cases were analyzed, thus the presented figures do not reflect the actual number of suicide deaths. Our research shows that most of the suicides that were not referred for autopsy were hangings, which admittedly increased the total number of suicides in the region, but was unlikely to influence the number of suicides committed using professional means. Nonetheless, an increase of the total suicide numbers will decrease the general percentage of suicides using professional knowledge. Secondly, medical histories provided limited information regarding previous suicide attempts. This information would have been useful to us in determining whether the method chosen was a first or subsequent attempt. If a different method was chosen for previous attempts it could be suggested that the use of professional knowledge the next time aimed to increase the chance of a lethal effect.
The increasing number of suicides makes it an important public health problem. Thus, suicide prevention has been recognized as "a global imperative" [1]. The high increase in the Polish suicide rate requires a national prevention initiative [2]. National suicide prevention programs might include prevention of psychiatric disorders and restricting the access to means [22]. However, means restriction policies needs an understanding of the method preferences of different professional groups [1].
Restricting access to the means of suicide has important life-saving potential and is a key element of suicide prevention [1,21]. It may serve to block acquired capability, thus reducing rates of suicide [28]. This is particularly significant when suicide happens impulsively. An effective strategy for preventing suicides and suicide attempts is to restrict access to the most common means [1]. The restriction of access should be implemented in conjunction with other suicide prevention strategies [23].

Conclusions
Although suicides planned and committed with use of professional knowledge are rare, they always succeed. Suicidal individuals who chose professional methods make lengthy preparations in order to ensure that the effect is lethal. Other studies, like ours, underline the possibilities of preventing suicides by restricting access to means. It should be borne in mind that limitation of accessibility to suicide means can save human lives.