Suicide risk in rapid cycling bipolar patients.

BACKGROUND

Rapid-cycling (RC) is a course modifier of bipolar disorder which often implicates a poor prognosis. However, the relationship of RC with suicidal features as a marker of impairment has been understudied.

METHODS

Three hundred and five patients (n=305) were included in a naturalistic, systematic prospective study in a single site setting. Patients with rapid-cycling (RC) were defined as having four or more manic, mixed or depressive episodes in the year prior to baseline assessment. The two groups were compared regarding clinical and sociodemographic variables, paying special attention to suicidal features. Statistical methods consisted of chi-square statistic for the comparison of categorical data, and Student's t test for dimensional variables normally distributed. Also, a General Linear Model was used to study the main effect of different sociodemographic and clinical variables on suicidality. All statistics were two-tailed, and significance was set at p less than 0.05.

RESULTS

Fifty-five patients (18%) were classified as RC, whilst 250 (82%) were considered as nonrapid-cycling (NRC). No significative difference was found in the prevalence of RC amongst bipolar I and II patients. RC was associated with depressive onset of bipolar disorder. The number of suicide attempts was significantly higher amongst RC (RC mean 0.82 [SD 1.85] vs. NRC 0.44[SD 0.94] t=2.09, p=0.37). Nonetheless, no significative differences were found between RC and NRC regarding the percentage of suicide attempters. On the other hand patients that presented RC showed a marked increase of lifetime history of suicidal ideation (Chi(2)=4.363, p=0.039). Finally, there were not any differences between RC patients and NRC in family history of suicide.

DISCUSSION: Bipolar patients with RC are more likely to attempt suicide. Intensive treatment of this marker should be considered.