Neuroprogressive effects of lifetime illness duration in older adults with bipolar disorder

Objective The aim of the present study was to examine the long‐term effects of bipolar disorder (BD) on brain structure (gray matter volumes). Methods Fifty‐four adults with BD [mean (standard deviation) age = 64.4 (5.4) years] underwent brain MR imaging along with comprehensive clinical assessment. Total gray matter, hippocampal, and amygdala volumes were extracted using methods developed through the Geriatric Neuroimaging Laboratory at the University of Pittsburgh (Pittsburgh, PA, USA). Results Lower total gray matter volumes were related to longer duration of BD, even when controlling for current age and cerebrovascular accident (CVA) risk/burden. Additionally, longer exposure to antipsychotic medication was related to lower gray matter volumes. Lower hippocampal volumes were related to total years of antipsychotic agent exposure and CVA risk/burden scores. Older age was related to lower total gray matter, hippocampal, and amgydala volumes. Conclusions Our study of older adults with BD supports the understanding that BD is a neuroprogressive disorder with a longer duration of illness and more antipsychotic agent exposure related to lower gray matter volume.