Dataset Information

Quantification of brain proton longitudinal relaxation (T₁ ) in lithium-treated and lithium-naive patients with bipolar disorder in comparison to healthy controls.

ABSTRACT:

Background

Proton longitudinal relaxation (T₁ ) is a quantitative MRI-derived tissue parameter sensitive to myelin, macromolecular, iron and water content. There is some evidence to suggest that cortical T₁ is elevated in bipolar disorder and that lithium administration reduces cortical T₁ . However, T₁ has not yet been quantified in separate groups containing lithium-treated patients, lithium-naïve patients, and matched healthy controls.

Methods

Euthymic patients with bipolar disorder receiving lithium (n = 18, BDL) and those on other medications but naïve to lithium (n = 20, BDC) underwent quantitative T₁ mapping alongside healthy controls (n = 18, HC). T₁ was compared between groups within the cortex, white matter and subcortical structures using regions of interest (ROI) derived from the Desikan-Killiany atlas. Effect sizes for each ROI were computed for BDC vs BDL groups and Bipolar Disorder vs HC groups.

Results

No significant differences in T₁ were identified between BDL and BDC groups when corrected for multiple comparisons. Patients with bipolar disorder had significantly higher mean T₁ in a range of ROIs compared to healthy controls, including bilateral motor, somatosensory and superior temporal regions, subcortical structures and white matter.

Conclusions

The higher T₁ values observed in the patients with bipolar disorder may reflect abnormal tissue microstructure. Whilst the precise mechanism remains unknown, these findings may have a basis in differences in myelination, macromolecular content, iron and water content between patients and controls.

SUBMITTER: Necus J

PROVIDER: S-EPMC7891392 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Quantification of brain proton longitudinal relaxation (T<sub>1</sub> ) in lithium-treated and lithium-naïve patients with bipolar disorder in comparison to healthy controls.

Necus Joe J Smith Fiona Elizabeth FE Thelwall Peter Edward PE Flowers Carly Jay CJ Sinha Nishant N Taylor Peter Neal PN Blamire Andrew Matthew AM Wang Yujiang Y Cousins David Andrew DA

Bipolar disorders 20191202 1

<h4>Background</h4>Proton longitudinal relaxation (T<sub>1</sub> ) is a quantitative MRI-derived tissue parameter sensitive to myelin, macromolecular, iron and water content. There is some evidence to suggest that cortical T<sub>1</sub> is elevated in bipolar disorder and that lithium administration reduces cortical T<sub>1</sub> . However, T<sub>1</sub> has not yet been quantified in separate groups containing lithium-treated patients, lithium-naïve patients, and matched healthy controls.<h4>Me ...[more]

PMID: 31755171

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