Structural and Functional Brain Alterations in Uremic restless legs syndrome patients: A Voxel-Based Morphometry and Functional Connectivity Study
DUN DING1, PENG LI2, Ji Xin Liu2, Xue Ying Ma2, and Ming Zhang2

1XI'AN JIAO TONG UNIVERSITY, XI'AN, China, People's Republic of, 2XI'AN, China, People's Republic of

Synopsis

To investigate the structure and function changes in the brain in uremic RLS patients using a resting-state function magnetic resonance imaging (fMRI) paradigm, we used A voxel-based morphometry(VBM) method and a seed-based method to find the abnormiy in end-stage kidney disease patients. Our results suggest that the characteristics of the connectivity changes may reflect the pathways involved in producing uremic RLS symptoms.

Sunopsis

To investigate the structure and function changes in the brain in uremic RLS patients using a resting-state function magnetic resonance imaging (fMRI) paradigm, we used A voxel-based morphometry(VBM) method and a seed-based method to find the abnormiy in end-stage kidney disease patients. Our results suggest that the characteristics of the connectivity changes may reflect the pathways involved in producing uremic RLS symptoms

method

29 ESRD patients on hemodialysis with restless legs syndrome and 27 age- and gender-matched control individuals (without renal or neurological problems) were recruited a prospective study. A voxel-based morphometry(VBM) method was analyzed the grey matter thickness of bilateral basal ganglia , and a seed-based method were used to explore the changes of VBM abnormality regions by functional neruoimage software. The clinical parameters and RLS severity were correlated analyzed. The characteristics of uremic RLS patients were compared to those of the controls.

results

We found that uremic RLS patients showed decreased thickness of right putamen, and that reduced right connectivity with the right parahipocampal gyrus, bilateral precentral gyrus, bilateral insulars, bilateral sensorimotor cortex and middle cingulate cortices. RLS severity was positively correlated with hemodialysis duration (P<0.05) and grade of Back anxiety inventory (BDI), was negatively correlated with blood urea nitrogen (BUN).

discussion

In our study, we observed alterations of thickness in the right putamen among uremic RLS patents, although the potential pathophysiology of this disease consists of hemodialysis, dopaminergic system dysfunction, brain iron deficiency, and calcium/phosphate imbalance, which may appear in end-stage kidney disease patients easily. And we found the connectivity reductions were located in sensorimotor areas, and the RLS severity was positively correlated with hemodialysis duration, both of them indicated the lower function of sensorimotor of uremic patients

Conclusions:

Our results suggest that the characteristics of the connectivity changes may reflect the pathways involved in producing uremic RLS symptoms and indicate that uremic RLS patients may have deficits in controlling and managing sensory information, and the hemodialysis duration contrivute to RLS severity, which may lead to bad emotion. Our study revealed that both the cerebral cortices and mood were impaired in ESRD patients on routine hemodialysis

Acknowledgements

We thank all the patients and volunteers for participating in this study. Also, the authors arehighly grateful to the anonymous reviewers for their significant and constructive commentsand suggestions, which greatly improve the article.

References

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Figures

Scatterplot shows correlation of RLS severity of duration (R = 0.423,P = .022).

Scatterplot shows correlation of RLS severity of BAI (R = 0.481,P = .008).

Note:All P <0.05, corrected for multiple comparisons.

The connectivity strength of right putamen with brain areas between uremic RLS patients and controls



Proc. Intl. Soc. Mag. Reson. Med. 24 (2016)
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