Rapid Cycling and lower hemoglobin in elderly bipolar patients with brain atrophy

Purpose: Bipolar disorder, medical comorbidity, and aging effects increase the risk for cognitive impairment in patients with bipolar disorder. In addition, brain atrophy in late life plays an important role in cognitive dysfunction. We attempted to find out the specific clinical characteristics that may identify patients with bipolar disorder at high risk for developing brain atrophy later in life. Methods: We recruited bipolar I patients (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) without concurrent dementia who were older than 60 years and had at least one psychiatric admission. Patients were divided into two groups based on the presence or absence of brain atrophy determined by structural magnetic resonance imaging at 1.5 T. Clinical data of bipolar illness-related features and general medical laboratory results were obtained by reviewing medical records and interviewing patients and family members. Results: There were 44 elderly patients with bipolar disorder in this study; 33 of them (75%) had cortical or subcortical brain atrophy. Multivariate analysis showed that, after adjusting for current age, significant predictive validity for brain atrophy was provided by a positive history of rapid cycling with adjusted odds ratio of 11.85 (95% confidence interval [CI] for odds ratio [OR]=1.21-116.57) or lower hemoglobin levels during affective episodes (adjusted odds ratio 0.44, 95% CI for OR=0.21-0.92). Conclusion: Elder patients with bipolar disorder and a history of rapid cycling and lower hemoglobin levels during acute affective episodes may have increased risk for developing brain atrophy later in life.