Risk Factors for Suicide in Schizophrenia Spectrum Disorders

Schizophrenia spectrum disorders (SSD) are psychotic disorders characterized by hallucinations, delusions, thought disorder, cognitive impairment, and, in the case of schizoaffective disorder, consistent mood symptoms. Most individuals with SSD have chronic symptoms that fluctuate in severity. Symptoms of SSD most often become evident during late adolescence and early adulthood.

People with SSD have higher rates of death by suicide than the general population. Lifetime risk has been estimated to be as high as 4-5 percent. In a recent paper published in the journal Schizophrenia Research, Juveria Zaheer, Mark Olfson, and colleagues describe predictors of suicide in individuals with SSD. This group used administrative health records in Ontario, Canada, to identify almost 76,000 individuals between the ages of 16 and 45 who received an initial diagnosis of SSD (schizophrenia, schizoaffective disorder, or psychosis not otherwise specified) between January 1993 and through December 2010. They determined deaths by suicide in this group of individuals through December 2012. The mean follow-up time was 9.6 years.

They found that 1,302 individuals (1.7 percent) with SSD committed suicide during this period. About half did so within five years of the initial diagnosis. Some of the risk factors for suicide in this group were similar to risk factors for suicide in the general population, including a history of depression, prior suicide attempts, and being male. In addition, the research team found that:

1. Individuals who were diagnosed at older ages were more likely to die by suicide. The research group classified individuals by age at first diagnosis: 16-25 years, 26-35 years, and 36-45 years. Death by suicide was more likely in the two older age groups for men and the oldest age group for women.
2. Drug use disorders in the two years prior to the initial SSD diagnosis increased the risk for suicide in females with SDD Interestingly, drug use disorders were not an independent risk factor for suicide in males with SDD.
3. Neither alcohol use disorders nor personality disorders in the two years prior to the initial SSD diagnosis were associated with increased risk of suicide independent of other associated risk factors.

It should be noted that comorbid alcohol and drug use disorders were assessed on the basis of diagnoses in individuals’ health records during the two years before an initial diagnosis of SSD. The investigators did not report data on the presence of alcohol and drug use disorders during the follow-up period.

The Zaheer group emphasizes that risk factors for suicide should be considered carefully when implementing a treatment plan for individuals with SSD. When evaluating a person with SSD for suicide risk, the clinician should inquire about the age of SSD diagnosis, history of depression, prior suicide attempts, and history of drug use disorders.

Nearly one person in 50 with SSD will die from suicide during adulthood. Much more work is needed to develop better psychosocial and somatic treatments to help those suffering from these devastating illnesses. In addition, more effort is needed to destigmatize SSD and help all in society realize that these individuals are ill and require psychiatric help. Although the unusual behaviors that persons with SDD may exhibit can be intimidating to those unfamiliar with these illnesses, empathy, support, and appropriate treatment can go a long way in helping those with SDD live longer and healthier lives.

This column was written by Eugene Rubin MD, Ph.D., and Charles Zorumski MD.