White Matter Abnormalities in Late Onset First Episode Mania: A Diffusion Tensor Imaging Study.

Area of Science:

• Neuroscience
• Geriatrics
• Psychiatry

Background:

• Late onset mania (first episode after age 50) is uncommon and may signal underlying neurological issues.
• Potential causes include vascular, degenerative, or inflammatory processes affecting white matter integrity.

Purpose of the Study:

• To investigate white matter integrity in patients with late onset mania using Magnetic Resonance Diffusion Tensor Imaging (DTI) and structural MRI.
• To correlate white matter integrity with cognitive function and clinical presentation.

Main Methods:

• Compared 22 late onset mania patients (>50 years) with 22 age-matched healthy controls.
• Utilized Diffusion Tensor Imaging (DTI) to measure fractional anisotropy (FA) for white matter integrity.
• Assessed white matter abnormalities using the Fazekas scale and performed cognitive tests (FAB, COGNISTAT, Trail Making A & B).

Main Results:

• Patients showed reduced white matter integrity in the corpus callosum and uncinate fasciculus compared to controls.
• Lower FA in the corpus callosum correlated with poorer neuropsychological test performance and higher Fazekas scores.
• Pathological white matter changes (Fazekas scale) were more frequent in late onset mania patients.

Conclusions:

• Late onset mania is associated with significant white matter abnormalities affecting interhemispheric and fronto-limbic networks.
• These abnormalities may underlie executive functioning and emotional processing deficits in late-life mania.
• The precise etiology of white matter integrity loss in late onset mania requires further investigation.