The life time prevalence of suicide in Schizophrenia is about 10 times higher than the general population. Early research suggested rates up to 13% but more recent studies report a lifetime suicide risk of 4 to 5%.
Suicide is one of the leading causes of premature death worldwide and approximately 1 million people commit suicide every year. It is estimated that 90% have a diagnosable psychiatric illness with depression making up 60% and schizophrenia, alcoholism and personality disorders accounting for a large proportion of the rest.Risk factors
The risk for suicide in schizophrenia is considered to be the highest in the early course of the illness, esp within the first year of diagnosis of the illness. White ethnicity has been found to be associated with higher suicide risk.
It is unclear if the age of onset of symptoms affects risk of suicide but 2 recent studies found a higher suicide rate amongst people with first episodes at older ages. A possible explanation for this might be that, after establishing themselves in a job and relationship/marriage and children, they find the possibility of losing all this too stressful and overpowering, having the knowledge that they will deteriorate.
Despite the suicide being highest in the early stages, suicide risk accumulates throughout the illness, so it can be considered to be high at any point during the illness. Suicide risk is especially high with admission to hospital. Estimates show that a 1/3 of patients with Schizophrenia that commit suicide do so during the hospital admission or within 1 week of discharge from hospital.
The number of psychiatric admissions has also been associated with increased risk of suicide. This probably reflects the severity of the illness.
Attempted suicide amongst patients with Schizophrenia is a strong risk factor for completed suicide, especially amongst males. Estimates of attempted suicides range from 20 to 40%.
Concurrent depression with schizophrenia is a strong risk factor for suicide in schizophrenia. Thus assessment for depression and treatment is essential. The one challenge facing clinicians however is differentiating clinical depression from the negative symptoms of Schizophrenia. The loss of emotional contact, inertia and loss of energy is common to both. Hopelessness and an extremely pessimistic view of the future are 2 key signs which should always be asked about. The presence of these impart a high risk of suicide.
The link between substance abuse, and suicide in schizophrenia is not clear. There have not been any consistent results in this field of study. One study has shown a link between illicit drug abuse, schizophrenia and suicide, but not with alcohol abuse.
Alcohol and substance abuse have been linked with poorer outcomes in a range of studies looking at violence, aggression, homelessness, severity and burden of mental illness, non compliance, other comorbid psychiatric diagnoses such as depression and anxiety, and criminality.
The link between substance abuse and suicide, may be mediated by increased impulsivity.
Several personal and social factors have been found to influence the suicide rate in Schizophrenia. Higher levels of education and higher IQ have been found to increase the risk of suicide. It may be due to the a greater sense of loss that such a person feels due to the illness.
Insight is the patients awareness of the disease and the need for treatment. Studies have suggested that good insight leads to an increased risk of suicide. This would be if the increased insight leads to hopelessness.
Poor compliance with treatment is also a risk factor.
Personality factors such as aggression and impulsivity increased risk.
Living alone or not living with one's family, recent loss increases risk
Suicide rates in the general population is higher for men. Results of studies of suicide in schizophrenia populations have not all been consistent. Studies have found equal rates, as well as higher rates for both genders. Risk for suicide seem to be different between the genders. Predictive factors for suicide in females are history of sexual abuse, partner abuse and loss of children. The method of suicide is also different with men choosing more violent methods than women like hanging, shooting and jumping from high structures.
It is not felt that the core symptoms of schizophrenia viz. hallucinations and delusions have are a strong risk factor for suicide. However it is the depressive symptoms of worthlessness, hopelessness and also agitation which are risk factors.
Having a family history of suicide increases the risk of suicide.
At present, despite having a theoretical database of the predictive factors for suicide, predicting the future remains as imprecise science. The risk factors discussed above have low predictive values.
What we do know is that the risk of suicide in schizophrenia is highest soon after diagnosis, at an earlier age, where there is a high level of functioning before the illness and where there is a good insight into the illness. Because schizophrenia is a lifelong illness, this risk remains over a long time, and together with depression, substance abuse, and previous attempts at suicide, are all important risk factors.
The diagnosis and proper treatment of depression with both medication and evidence-based therapies is crucial in reducing suicide risk. There is growing evidence for an anti-suicidal effect of Clozapine.
Interventions to reduce substance abuse are essential, as well as adequately treating schizophrenia symptoms, and maintaining compliance and increasing vigilance at times of high risk.