MedWire News: Among people with bipolar disorder, the risk of suicide is greatest during major depressive or mixed depressive/manic episodes of the illness, researchers have found.

Dr Erkki Isometsä, from the University of Helsinki in Finland, and team studied the incidence of suicide attempts in different phases of illness in 81 patients with type I and 95 with type II bipolar disorder over a period of 18 months.

Overall, 20% of patients reported at least one suicide attempt and there were 53 suicide attempts in total.

Further analysis revealed that the incidence of suicide attempts was 37-fold higher during combined mixed and depressive mixed phases of illness, and 18-fold higher during major depressive phases compared with other phases of illness.

Indeed, no patients attempted suicide during either manic or mood symptom-free phases of illness.

Overall, patients with bipolar II disorder spent more time in mixed and depressive phases of illness than those with bipolar I disorder, and were therefore twice as likely to attempt suicide.

"The incidence of suicide attempts varies remarkably between illness phases, with mixed and depressive phases involving the highest risk by time," summarise Dr Isometsä and team in the journal Bipolar Disorders.

They conclude: "The fast and effective management of mixed and depressive phases may be crucial in reducing risk for attempting suicide."