Alterations in structural and functional connectivity of thalamic subregions in patients with uremic pruritus undergoing peritoneal dialysis

Uremic pruritus (UP) significantly compromises the quality of life in patients with end-stage renal disease undergoing peritoneal dialysis. Although the precise pathophysiological mechanisms of UP remain elusive, the thalamus, which is integral to processing sensory information, is potentially implicated in its development. This study aimed to investigate alterations in the structure and resting-state functional connectivity (rsFC) of thalamic subregions in patients with UP. A total of 42 UP patients and 50 healthy controls (HCs) were included in the study. Volumetric and seed-based rsFC analyses were employed to assess structural and functional changes in the thalamic subregions. Correlation and mediation effect analyses were used to explore the relationships among neuroimaging structural features, functional features, and UP severity. Compared to HCs, patients with UP showed a significant reduction in volume in the right medial prefrontal thalamus, bilateral Stha (Sensory thalamus), and right posterior parietal thalamus. In UP patients, regions of reduced rsFC between the bilateral Stha and the whole brain were primarily localized within the sensory motor network. The decreased volume of thalamic subregions and rsFC were closely associated with UP severity. It was found that the volume of R_Stha directly influences the severity of pruritus in UP patients, but this effect does not manifest through rsFC between R_Stha and left supplementary motor area or left paracentral lobule. Patients with UP exhibited changes in structural and functional connectivity within specific thalamic subregions, providing neuroimaging insights into the neural mechanisms of UP.