Mood stabilisers and risk of stroke in bipolar disorder

Background Research on the risk of stroke following the use of mood stabilisers specific to patients with bipolar disorder is limited.Aims In this study, we investigated the risk of stroke following the exposure to mood stabilisers in patients with bipolar disorder.Method Data for this nationwide population-based study were derived from the Taiwan National Health Insurance Research Database. Among a retrospective cohort of patients with bipolar disorder (n = 19 433), 609 new-onset cases of stroke were identified from 1999 to 2012. A case-crossover study design utilising 14-day windows was applied to assess the acute exposure effect of individual mood stabilisers on the risk of ischaemic, haemorrhagic and other types of stroke in patients with bipolar disorder.Results Mood stabilisers as a group were significantly associated with the increased risk of stroke in patients with bipolar disorder (adjusted risk ratio, 1.26; P = 0.041). Among individual mood stabilisers, acute exposure to carbamazepine had the highest risk of stroke (adjusted risk ratio, 1.68; P = 0.018), particularly the ischaemic type (adjusted risk ratio, 1.81; P = 0.037). In addition, acute exposure to valproic acid elevated the risk of haemorrhagic stroke (adjusted risk ratio, 1.76; P = 0.022). In contrast, acute exposure to lithium and lamotrigine did not significantly increase the risk of any type of stroke.Conclusions Use of carbamazepine and valproic acid, but not lithium and lamotrigine, is associated with increased risk of stroke in patients with bipolar disorder.Declaration of interest None.