Neurodegenerative changes in patients with clinical history of bipolar disorders

Abstract

Neurodegeneration in bipolar disorder (BPD) is poorly understood. Therefore, the current study was designed to assess the immunohistochemical changes in neurodegenerative markers in patients with BPD. Eleven consecutive autopsy cases diagnosed with BPD were analyzed. Sections were obtained from archival paraffin blocks of representative areas and stained using conventional methods, as well as immunostained with several antibodies to screen for neurodegenerative diseases. Age-and nonargyrophilic grains (AGs) degeneration matched controls were selected for each case. Clinical information was retrospectively collected from medical charts. All patients were men, and the average age of death was 70 years. Neuropathological diagnoses included dementia with grains (2), argyrophilic grain disease (2), corticobasal degeneration (CBD, 1), Lewy body disease (1), hypoxic encephalopathy (1) and cerebral infarction (1). All cases showed AGs to various degrees. Three patients died in their 50s; one demonstrated dementia with Lewy bodies, while the other two showed abundant AGs in the thalamus and amygdala. Of the three patients who died in their 60s, one showed AGs preferentially in the thalamus and amygdala, while the others demonstrated limbic predominance. The patients who died in/after their 70s demonstrated AGs similar to controls, except for the patient with CBD. Our data provides potentiality that neurodegenerative diseases may be an underlying pathology in certain cases of BPD.

Current understanding of bipolar disorder: Toward integration of biological basis and treatment strategies

“…In Japan, overdiagnosis of BD, which is accelerated by the premature approval of near‐infrared spectroscopy as a diagnostic tool, is discouraged . The boundary between genuine BD and secondary BD can be obscured, as evidenced by a recent neuropathological study of post‐mortem brains from aged BD patients that showed a high frequency of tau pathology in emotion‐related brain areas . Soon, PET might be used for the distinction between genuine BD and secondary BD .…”

Neuropathological comorbidity associated with argyrophilic grain disease

“…The first reported clinical feature in AGD cases is dementia . Subsequently, it was also reported that AGD may be associated with several psychiatric conditions in late life . Pathologically, it is known that AGD often coexists with other neurodegenerative diseases.…”

“…1 Subsequently, it was also reported that AGD may be associated with several psychiatric conditions in late life. [2][3][4] Pathologically, it is known that AGD often coexists with other neurodegenerative diseases. However, whether the comorbidity reflects some pathogenic linkage and affects clinical presentations in other diseases remains unclear.…”

The Underrated Circadian System and Its Contribution to Neurodegeneration in Mood Disorders

“…This was for a while mainly seen in the context of neurotransmitter availability in relevant brain structures and, according to this context, actions of antidepressants were interpreted and developed. The suspicion that neurodegeneration may play a crucial role is not entirely new, but has gained increasing attention mainly during the last years [1][2][3][4][5][6] . In the beginning, this seemed more likely in cases in which patients exhibited socially unacceptable behavior or signs of dementia, [7][8][9][10] but was less considered in exclusively depressive disorders, a view that is actually changing 2,4 .…”

“…The suspicion that neurodegeneration may play a crucial role is not entirely new, but has gained increasing attention mainly during the last years [1][2][3][4][5][6] . In the beginning, this seemed more likely in cases in which patients exhibited socially unacceptable behavior or signs of dementia, [7][8][9][10] but was less considered in exclusively depressive disorders, a view that is actually changing 2,4 . On the one hand, reduced neurotransmitter concentrations in the synaptic cleft may already be associated with the initiation of neurodegenerative processes, as judged from the influence of other synaptopathic changes, 10,11 and from the fact that classic antidepressants can also display neuroprotective properties 12 .…”