Cerebrovascular Disease and Bipolar Disorder

Bipolar disorder has been strongly associated with cardiovascular disease although the relationship between the two conditions is complex with regard to directionality and mechanisms. The defining syndromes of bipolar disorder, mania and hypomania, can occur following stroke, including in individuals who are seemingly otherwise not at risk based on age, family history, and past psychiatric history. This has led many experts to conclude that bipolar disorder may occur secondary to stroke. Individuals with idiopathic forms of bipolar disorder further face a considerably increased risk for cerebrovascular mortality and stroke. This elevation in risk is large and estimated to be approximately twice that expected from general population estimates for both cerebrovascular mortality and events. There exist a variety of mechanisms that may link bipolar disorder with cerebrovascular disease, and some risk factors may predispose vulnerable individuals to both conditions. These mechanisms include–though are not limited to–inflammation, oxidative stress/mitochondrial dysfunction, abnormalities in the hypothalamic-pituitary-adrenal axis, and sleep disorders. Clinicians should be mindful of the potential for stroke to induce mania and recognize that individuals with bipolar disorder are at special risk for vascular disease, a risk that early and assertive clinical intervention may potentially mitigate.