The risk factors for elderly patients with bipolar disorder having cerebral infarction

Patients with bipolar disorder are at high risk of developing strokes in the older life. Silent cerebral infarctions (SCIs) could be common in the elderly patients with bipolar disorder, but only small sample size reports are available. The purpose of this study was to assess the proportion of SCIs and determine the risk factors for cerebral infarction in elderly patients with bipolar disorder.

We recruited 43 patients with bipolar disorder over the age of 60 to undergo whole-brain magnetic resonance imaging (MRI). We divided them into 2 groups depending on whether infarction was present, and compared the potential variables of these 2 groups.

There were 28 elderly patients with bipolar disorder (65.1%) having MRI-proven cerebral infarction. The SCIs were detected in 59.5% (N = 22) of 37 patients without a history of stroke, including 61.3% of 13 patients with late-onset age (>50 years) and 46.7% of 30 patients with typical-onset age (<50 years). Logistic regression revealed that comorbidity with metabolic diseases (95% confidence interval [CI] for odds ratio [OR] = 1.24-40.59) was most strongly associated with cerebral infarction. The leukocyte counts (95% CI for OR = 1.10-3.93) and fasting blood sugar (95% CI for OR = 1.00-1.07) during the most recent acute psychiatric admission may be substituted as the risk factors.

Cerebral infarctions tend to be neglected in more than half of the elderly patients with bipolar disorder, regardless of their age at onset. Metabolic abnormality and systemic inflammation may be the risk factors.