Carbamazepine, valproic acid may pose increased stroke risk in bipolar patients
Mood stabilizers for bipolar disorder are implicated in the risk of stroke, which appears to vary among the different types of drugs, as suggested in a recent study. Carbamazepine carries the highest risk of stroke, followed by valproic acid, whereas lithium and lamotrigine have a null effect.
The study used data from the Taiwan National Health Insurance Research Database and identified 19,433 patients with bipolar disorder. Of these, 609 developed stroke. Researchers applied 14-day windows to evaluate the acute exposure effect of individual mood stabilizers on the risk of ischaemic, haemorrhagic and other types of stroke in the study population.
Mood stabilizers overall were associated with about a 20-percent increase in stroke risk (adjusted risk ratio, 1.26; p=0.041).
On separate analysis, acute exposure to carbamazepine posed the highest risk of stroke (adjusted risk ratio [RR], 1.68; p=0.018), especially the ischaemic type (adjusted RR, 1.81; p=0.037). Acute exposure to valproic acid, on the other hand, was associated with a heightened risk of haemorrhagic stroke (adjusted RR, 1.76; p=0.022).
Acute exposure to neither lithium nor lamotrigine significantly increased the risk of any type of stroke.
The current data may be used as a guide for choosing which mood stabilizers to use in the management of patients with bipolar disorder who require acute therapy for affective symptoms and who already have the risk factors for stroke, according to the researchers.