Suicide after parasuicide

Predicting suicide is a delicate matter, certainly difficult even in groups of patients at high risk. A paper in this issue focuses on previous parasuicide as a predictor of suicide (p 1155) and shows that the risk persists without decline for two decades.¹ This observation is relevant for the clinical assessment of risk of suicide and has implications for the treatment of parasuicide as well.

In a large meta-analysis, a history of parasuicide or attempted suicide increased the risk of suicide to 40 times that of the general population.² An attempted suicide that was recognised in health care thus implied a higher risk than having a mental disorder such as major depression, personality disorder, or dependence on alcohol. The risk of suicide is generally most prominent during the first months after psychiatric care.³ The risk of repetition and consequently of suicide is believed to be highest during the first one or two years after an episode of parasuicide.⁴,⁵ Follow up studies of hospitalised patients who have attempted suicide show that the initial high risk declines each year.⁶ But recent studies of people who have harmed themselves deliberately and attempted suicide show that the risk persists for a long time.⁵,⁷ In a retrospective study of suicide we found that the interval between first suicidal behaviour and the suicide was related to the patient's sex and mental disorder. For example, in patients with borderline personality disorder or schizophrenia the suicidal process can take a long time.⁸ Follow up studies of parasuicide would improve if diagnostic subgroups were taken into consideration.

Severity of the attempt indicates higher risk. Extra caution is also warranted in situations with repeated parasuicide, especially when these occur with increasing frequency. More extensive planning of the current parasuicide may indicate a high risk. Mental disorder in general and depressive disorder in particular, if present at the index parasuicide, strengthens the risk for poor outcome. Likewise, the presence of substance abuse at the time of parasuicide increases the danger.⁹ Comorbidity such as substance abuse and another mental disorder is also noteworthy. Concomitant somatic illness should be assessed, especially in elderly people.¹⁰

The view that parasuicide and suicide involve totally different populations has been found to be inaccurate.¹¹ The prevalence of parasuicide is high also in retrospective systematic interview studies of suicide victims. In a study of young adults, previous parasuicide was found in 60% of young men and 80% of young women.⁸ This is a higher rate than among adults in general. Among men of all ages, previous parasuicide was found in about a third and among women of all ages in about two thirds. Irrespective of age, women have higher rates of parasuicide even among those who eventually die by suicide. Expectedly, repeated parasuicide is common in people who commit suicide. Three or more parasuicides occurred in 17% of men and 56% of women.⁸

Can we rely on the answers that patients give when we question them about suicidal ideation in emergencies? Certainly, an empathic interview with the patient yields an honest answer in most instances. Further, the circumstances of the parasuicide are well worth exploring in the encounter with the patient. To what extent the verbal presentation of suicidal thoughts is valid in assessing the risk of suicide is still doubtful. Most people who commit suicide have communicated such ideation in a more obvious or disguised manner. Fewer than half of them did communicate their intention to family members during their previous suicidal episode.⁸ In a study of suicide in elderly people, the doctors responsible for treating them were less aware of the suicidal thoughts than the family members.¹² In relation to this week's paper there is a good reason to point at previous acts of suicidal behaviour as the most reliable issue to penetrate in the clinical interview.¹ To pay attention to previous parasuicide in the assessment of the patient in the emergency department is crucial, because it may indicate a serious risk even if the act was committed several years ago.