Suicide is among the leading causes of death worldwide. While there have been significant advances in suicide research as well as an increase in the treatment of suicidal people, the rate of these behaviors has not changed as a result. In the year 2000 approximately one million people died by suicide and it is now estimated that by 2020 suicide will become the tenth most common cause of death in the world (Bolton, et al., 2010). Suicidal behaviors commonly run on a continuum from developing an idea to kill oneself, making a plan for the act, acting out the plan, with or without suicide as the final outcome (Uwakwe & Gureje, 2011). Although the etiology of suicide is not well known, numerous studies have shown that mental disorders are among the strongest known predictors of suicide attempts and deaths. Most studies …show more content…
examine the associations between individual disorders and suicidal behaviors, excluding an important factor that mental disorders are highly comorbid.
When examined this way, practically all mental disorders can be linked with suicidal behavior. The effects of comorbidity need to be taken into consideration in a more rigorous manner to clarify the unique associations of mental disorders with suicidal behavior (Hwang, Kessler, Nock, Sampson, 2010). Knowledge of which disorders that are uniquely predictive of suicidal behaviors, and the manner in which comorbidity contributes to these outcomes, is needed to better understand the mechanisms through which mental disorders lead to suicidal behaviors (Hwang, Kessler, Nock, Sampson, 2010).
Study #1
Mental disorders, comorbidity and suicidal behavior.
Abstract:
Hwang, Kessler, Nock, and Sampson (2010) examined unique associations between individual
disorders and subsequent suicidal behaviors (lifetime occurrence and age-of-onset of suicide ideation, plans, and attempt). Data was from the National Comorbidity Survey Replication (NCS-R), a nationally representative survey of the U.S. household population. It used a multi-stage clustered-area probability design interviewing 9,282 English-speaking adults (18+ years old), face-to-face, to assess commonness and correlates of DSM-IV mental disorders. The interview was administered in two parts: Part I included a core diagnostic assessment of DSM-IV mental disorders along with questions on suicidal behaviors to all 9,282 participants; Part II included questions relating to links and additional disorders to a probability sub-sample of 5,692 participants. 16 mental disorders included in the analysis were anxiety disorders, mood disorders, impulsive-control disorders and substance use disorders (alcohol and illicit drug abuse or dependence) and each of these disorders demonstrated significant association with increased risk of suicidal behaviors. 66% of people who contemplated suicide reported having prior mental illness, 80% of those people attempted suicide and 83% of the people, who attempted, made a planned attempt. A strong positive association was found between suicide behaviors and comorbidity; as the number of comorbid disorders increased, the suicidal behaviors increased as well. Depression predicted suicide ideation, while disorders with severe anxiety and poor impulse-control went a step further to a suicidal plan or attempt. According to the results, there was a unique association between specific mental disorders and different suicidal behaviors.
Critique:
This study proved the correlation between mental disorders, comorbidity and suicidal behaviors, but it had limitations. First, a wide range of mental disorders were analyzed during this study, but not all disorders were included. For instance, psychosis, Axis II (personality) disorder, and schizophrenia, amongst other disorders, were missing and considered to be disorders known to be linked to suicidal behaviors. Secondly, the severity and chronicity of each of the disorders were not examined in this study. These are two key factors in disorders that better correlate the strength of the associations between disorders and suicidal behaviors. Thirdly, there was no investigation into the complex comorbidity of mental disorders and possible physical illnesses. Medical conditions have been reported as risk factors for suicidality. Finally, the data was based on reflective self-reports of the occurrence, and timing of mental disorders and suicidal behaviors, making the study subjective to a recall bias. This could cause false results if the provided information turned out to be inaccurate. Despite these limitations, this study was well-designed and accurate pertaining to the data collected.
Study #2
Relationship of comorbidity of mental and substance use disorders with suicidal behavior.
Abstract:
Gureje and Uwakwe (2011) used the Nigerian National Survey of Mental Health and Well-being, a community survey conducted in Nigeria to select non-institutionalized adults (18+ years) to a total of 6,752 people. The interview was a face-to-face assessment administered in two parts: Part I consisted of a core of diagnoses to all 6,752 participants; Part II consisted of sections for the assessment of risk factors, consequences and links of disorders to a sub-sample of 2,143 participants. The core mental disorders included mood disorders, anxiety disorders, impulse control disorders, substance, and drug use disorders. Suicidality was based on three possible suicidal experiences: ideas, plans, and attempts. Depending on the suicidal experience a series of questions were asked about occurrence, number of times, injury or medical attention, serious attempt or for attention. People with mental illness were proved more likely to attempt suicide (57%) than not at all (12%). Lifetime suicide attempters were also more likely to demonstrate comorbid conditions. The comorbid conditions suggested that mood disorders were independently associated with suicidal outcomes, and significantly higher in suicidal attempts overall than any other disorder. It also partly explained the association of anxiety disorders and almost fully accounted for the association of substance use disorders with suicidal outcomes. These results proved that comorbidity is an important factor in the association of mental and substance use disorders with suicidal behavior.
Critique: This study proved that mental disorders were clearly found associated with suicidal behaviors and comorbidity significantly elevated the risk of suicide attempts. There were some limitations with this study as well. First, the severity and chronicity of the disorder weren’t taken into account. It’s possible that the severity or chronicity of a particular mental disorder may influence the occurrence of suicidal behaviors. Secondly, in considering comorbidity, there was no investigation into the complex comorbidity of mental disorders and possible physical illnesses. Medical conditions have been reported as risk factors for suicidality. Thirdly, all the mental disorders weren’t included, some which have been known to be associated with suicide, for example, Axis II (personality) disorders, psychosis and schizophrenia. The study was strictly Axis I disorders. Finally, in all cross-sectional surveys where suicidal behaviors are assessed on the basis of retrospective reports a recall bias is considered. This bias may have led to an underestimation of the suicidal scale in the report, providing false information and causing there to be false results. Despite these limitations, the results of this study were accurate and the study itself was well-designed.
Study #3
Cross-National Analysis of Associations among Mental Disorders and Suicidal Behavior
Abstract:
Angermeyer et al. (2009) used the WMH surveys were carried out in 21 countries in Africa, the Americas, Asia and the Pacific, Europe, and the Middle East. The total sample size was 108,664 people. The face-to-face interviews were conducted in two parts: Part I which contained assessments of the lifetime prevalence and age-of-onset of core mental disorders and suicidal behaviors such as, suicidal ideation, plans and attempts to the total sample size 108,664; Part II assessed potential links and disorders of secondary interest in a sub-sample of 54,992. The 16 mental disorders included in the analysis were anxiety disorders, mood disorders, impulsive-control disorders and substance use disorders (alcohol and illicit drug abuse or dependence). About half of the people who had attempted suicide reported a prior mental disorder in both developed 66% and developing 55% countries. Overall, mental disorders were equally predictive in developed and developing countries, with a key difference being that the strongest predictors of suicide attempts in developed countries being mood disorders, whereas in developing countries impulse-control, substance use and PTSD were most predictive. This study found that a wide range of mental disorders increased the chances of experiencing suicidal ideation. However, after controlling for comorbidity, only disorders characterized by anxiety and poor impulse-control predict which people with suicidal ideation act on such thoughts. These findings provide a more fine-grained understanding of the associations between mental disorders and subsequent suicidal behaviors, as well as how mental disorders predict suicidal behavior similarly in both developed and developing countries.
Critique:
This study proved that even after the effect of comorbidity, each disorder considered alone significantly predicted suicide attempts, but was considerably higher with comorbidity. This study also accounts for several key limitations. First, although there were exceptional amount of response rates overall, response rates varied cross-nationally and could limit the generality of the results. Second, these data are based on retrospective self-reports of the occurrence and timing of mental disorders and suicidal behavior, which introduce potential biased recall. It is also possible that the extent of recall bias differs across suicide ideation, plans, and attempts, which could have influenced the study results. Third, a broad range of disorders were assessed, severity, complexity or chronicity were not considered of each disorder. This could have led to an underestimate of the strength of associations between mental disorders and suicidal behavior. Despite these limitations, the study was well-designed and accurate.
Conclusion The limitations found in each of these studies were the same throughout each of the studies. Although there were many disorders covered in each of these studies, some disorders that are directly linked to suicidal behaviors were not addressed in any of the studies. Severity, complexity, and chronicity of each disorder were also not discussed in any of the studies and could be important in predicting the transition from suicide ideation to attempts. All studies were conducted via a survey method which in turn bases the data on retrospective self-reports of the occurrence and timing of mental disorders and suicidal behavior, which introduce potential problems with underreporting and biased recall. Limitations such as these are inevitable when conducting a cross-sectional survey in which suicidal behaviors are being assessed through retrospective self-reports because the studies are based off of the facts given by the participants. Despite these limitations, the facts from each these studies, consistently represented the same results, a high association between mental disorders and suicidal behavior. Comorbidity increased these behaviors in each study, as well as influenced suicidal behaviors from ideation to plans or attempts. As earlier pointed out, suicidal behavior is without a doubt complex and unlikely to have a simple relationship with mental disorders. Our findings suggest that comorbidity is important in regards to the relationship of suicidal behavior to most mental disorders and the relevance of comorbidity to suicidality derive from different standpoints in each individual disorder.
References
Nock, M. K., Hwang, I. I., Sampson, N. A., & Kessler, R. C. (2010). Mental disorders, comorbidity and suicidal behavior: Results from the National Comorbidity Survey Replication. Molecular Psychiatry, 15(8), 868-876.
Uwakwe, R., & Gureje, O. (2011). The relationship of comorbidity of mental and substance use disorders with suicidal behaviors in the Nigerian Survey of Mental Health and Wellbeing. Social Psychiatry & Psychiatric Epidemiology, 46(3), 173-180.
Nock, M. K., Hwang, I., Sampson, N., Kessler, R. C., Angermeyer, M., Beautrais, A., & ... Levinson, D. (2009). Cross-National Analysis of the Associations among Mental Disorders and Suicidal Behavior: Findings from the WHO World Mental Health Surveys. Plos Medicine, 6(8), 1-17.
MacLean, J., Kinley, D., Jacobi, F., Bolton, J. M., & Sareen, J. (2011). The relationship between physical conditions and suicidal behavior among those with mood disorders. Journal Of Affective Disorders, 130(1/2), 245-250.