Suicide attempts: differences between unipolar and bipolar patients and among groups with different lethality risk

The present naturalistic study aimed to distinguish between suicide attempts (SAs) of bipolar and unipolar patients, and among SAs characterized by different lethality risk.

The records of 2395 consecutive admissions to our psychiatric intensive care unit (PICU) were assessed for presence of suicide attempt (SA). Cases of SA were rated for symptom severity with the brief psychiatric rating scale (BPRS), the scale for the assessment of positive symptoms (SAPS), the scale for the assessment of negative symptoms (SANS), the mini mental state examination (MMSE), the global assessment of functioning scale (GAF) and the clinical global impression (CGI). An original questionnaire was administered to explore clinical aspects related with suicidal behavior.

Among 2395 admissions, 80 (3.3%) had attempted suicide. Fifty-three cases (66.2%) suffered from a mood episode, including 22 (27.5%) with unipolar depression and 31 (38.7%) with bipolar depression (types I and II combined) or mixed state, while 27 (33.8%) cases received other diagnoses. Forty-eight (60%) cases had attempted suicide prior to the index episode. Ten cases (12.5%) had a relative who attempted or committed suicide. Thirty-nine cases (48.7%) described their SA as impulsive. Twenty cases (25.0%) reported alcohol ingestion before SA. In comparison with women, men used more violent methods. Cases characterized by a non-lethal risk SA had higher BPRS psychotic cluster and SAPS scores than cases with either low or high lethal risk SA. Bipolar cases were over-represented in the high lethality risk group. BPRS anxiety-depressive cluster score was higher in unipolar than in bipolar cases.

The sample may not be representative of all patients with SA. The questionnaire has not been standardized for use in psychiatric populations.

The higher proportion of high lethal risk SA in bipolar cases suggests that the risk of completed suicide is higher in bipolar disorder than in unipolar depression. The risk of lethality in SA was not associated with the intensity of symptoms of anxiety and depression.