Bipolar disorder patients who also have substance misuse disorders are at an increased risk of suicide compared with patients who are non- drug dependent or do not abuse drugs, suggest Canadian and Italian scientists.

It is estimated that between 25 and 60 per cent of patients with bipolar disorder make at least one suicide attempt during the course of their illness. Despite this, few studies have examined the clinical predictors of suicide attempts in these patients.

Researchers administered the Structural Clinical Interview for DSM-IV to 336 patients with a diagnosis of bipolar I, bipolar II or schizoaffective disorder (bipolar type).

The team, from the University of Toronto and the University of Milan, then compared clinical predictors of suicide attempts in attempters and non-attempters. They found that 26 per cent of the subjects had made at least one suicide attempt.

Lifetime co-morbid substance use disorders were diagnosed in 34 per cent of the subjects, while lifetime comorbid anxiety disorders were diagnosed in 26 per cent of the subjects.

Significantly, patients with a lifetime comorbid substance use disorder (that is, drug abuse and dependence) had a 40 per cent lifetime rate of attempted suicide compared with a rate of 24 per cent for those without the comorbidity.

The team speculates that the relationship between lifetime comorbid substance use disorder and suicide attempts may have a genetic origin and/or may be explained by severity of illness and trait impulsivity.

They add that further research is needed to examine severity of illness, impulsivity and the temporal link between substance use and suicide attempts.

Source: www.thealmagest.com  21.07.2013