BACKGROUND

Multiple studies have indicated an association between somatic symptom disorder (SSD) and suicidal symptoms, particularly suicidal ideation. Nevertheless, whether SSD is associated with a risk of suicide mortality remains unclear. In addition, how SSD-related psychiatric comorbidities such as bipolar disorder and major depressive disorder influence the risk of suicide remains unknown.

METHODS

In this study, 38,483 patients with SSD and 153,932 age- and sex-matched non-SSD individuals were followed up from 2003 to 2017. Suicide was evaluated within this study period, and major psychiatric disorders such as schizophrenia, bipolar disorder, major depression, alcohol use disorder (AUD), and substance use disorder (SUD) were identified. After these major psychiatric comorbidities were adjusted for, time-dependent Cox regression models were used to determine the influence of SSD on the risk of suicide.

RESULTS

Patients with SSD had a higher risk of suicide (hazard ratio [HR] = 3.41) compared with their non-SSD counterparts, regardless of their psychiatric comorbidities. Patients with SSD and comorbidities such as schizophrenia (HR = 5.55), bipolar disorder (HR = 5.99), major depression (HR = 10.24), AUD (HR = 4.33), and SUD (HR = 4.33) were at an increased risk of suicide.

LIMITATION

Comorbid anxiety disorders with SSD were not assessed for the suicide risk in the present study.

DISCUSSION

SSD is an independent risk factor for suicide. Both SSD and its associated psychiatric comorbidities can be used to develop strategies aimed at suicide prevention.